CA1170898A - Tubular packaging material and method for its manufacture - Google Patents
Tubular packaging material and method for its manufactureInfo
- Publication number
- CA1170898A CA1170898A CA000382885A CA382885A CA1170898A CA 1170898 A CA1170898 A CA 1170898A CA 000382885 A CA000382885 A CA 000382885A CA 382885 A CA382885 A CA 382885A CA 1170898 A CA1170898 A CA 1170898A
- Authority
- CA
- Canada
- Prior art keywords
- tubing
- heat
- water
- range
- treatment
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- A—HUMAN NECESSITIES
- A22—BUTCHERING; MEAT TREATMENT; PROCESSING POULTRY OR FISH
- A22C—PROCESSING MEAT, POULTRY, OR FISH
- A22C13/00—Sausage casings
- A22C13/0013—Chemical composition of synthetic sausage casings
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31855—Of addition polymer from unsaturated monomers
- Y10T428/31859—Next to an aldehyde or ketone condensation product
- Y10T428/31862—Melamine-aldehyde
- Y10T428/31866—Impregnated or coated cellulosic material
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31855—Of addition polymer from unsaturated monomers
- Y10T428/31859—Next to an aldehyde or ketone condensation product
- Y10T428/3187—Amide-aldehyde
- Y10T428/31873—Urea or modified urea-aldehyde
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31942—Of aldehyde or ketone condensation product
- Y10T428/31949—Next to cellulosic
- Y10T428/31953—Modified or regenerated cellulose
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
- Y10T428/31971—Of carbohydrate
- Y10T428/31975—Of cellulosic next to another carbohydrate
- Y10T428/31978—Cellulosic next to another cellulosic
- Y10T428/31986—Regenerated or modified
Abstract
ABSTRACT OF THE DISCLOSURE
Disclosed is a tubular packaging material for sausage casings, comprising a carrier tubing comprised of cellulose hydrate and containing in its wall from about 5 to 12% by weight of water and from about 18 to 28% by weight of a plasticizer: and a coating on the inside and on the outside of the carrier tubing of a water-insoluble heat-cured synthetic condensation product wherein the carrier tubing is characterized by a swelling value in the range from about 80 to l20%, and the tubular packag-ing material, after soaking in water at a temperature between about 40 to 50°C for a period of about 30 minutes and subsequent cooling to about room tempera-ture, is characterized by dimensions in the wet state which are 2 to 6% greater than those before the soaking in water. Also disclosed are methods for preparing the packaging material.
Disclosed is a tubular packaging material for sausage casings, comprising a carrier tubing comprised of cellulose hydrate and containing in its wall from about 5 to 12% by weight of water and from about 18 to 28% by weight of a plasticizer: and a coating on the inside and on the outside of the carrier tubing of a water-insoluble heat-cured synthetic condensation product wherein the carrier tubing is characterized by a swelling value in the range from about 80 to l20%, and the tubular packag-ing material, after soaking in water at a temperature between about 40 to 50°C for a period of about 30 minutes and subsequent cooling to about room tempera-ture, is characterized by dimensions in the wet state which are 2 to 6% greater than those before the soaking in water. Also disclosed are methods for preparing the packaging material.
Description
`" 1~7~898 TUBULAR PACKAGING MATERIAL AND METHOD FOR
.
I-TS MANUFACTIJRE
-BACKGROUND OF THE IN~ENTION
_ _ _ The present invention relates to a tubular packaging material, in particular to a sausage casing having a cellulose hydrate-based carrier tubing bearing a water-insoluble condensation product on at least one side, and also to processes for its manu~acture and to the use of the packaging material.
When artificial sausage casings are used in accordance with their i.ntended purposes, they are usually soaked in water before they are filled with a sausage emulsion, in order to provide them with the suppleness which is a pre-condition for filling the casings with a sausage emulsion without causing damage. For soaking in water, water at a temperature of about ~0 to 50C is allowed to act on the casings for a period of about 30 minutes.
In the manufacture of artificial sausage casings based on cellulose hydrate (U.S. Patent ~.
1 1~08~
No, 2,999,757), the tubing of cellulose hydrate gel is dried under conditions under which the tubing volume increases. In the case of these tubular casings, the surface area decreases during the soaking in water, before they are used in accordance with their intended purpose, by about 3 to 6%, relative to the area before soaking in water. The tubular casings which have been soaked in water and shrunk in this manner are then filled in the known manner with a sausage emulsion, by forcing the latter into the tubular casing which is closed at one end, and then sealing the other end of the casing.
SUM~RY OF THE INVENTION
It is an object of the present invention to provide an improved tubular packaging material which can be used as an artificial sausage casing for sausage preserves, and which is composed of a carrier tubing based on cellulose hydrate and on the wall of which a water-insoluble heat-cured synthetic condensation product is present.
It is another object of the invention to provide such a packaging material wherein a tubular packaging casing initially increases its dimensions, due to soaking in water before it is used in accord-ance with its intended purpose, and subsequently makesclose contact witK the filling after it has been filled with a sausage emulsion and dried.
It is also an object of the invention to provide a packaging material wherein, due to the structural and chemical composition of the packaging material and the structural properties of the carrier tubing, the material is substantially resistant to an enzymatically caused degradation of the cellulose hydrate molecules forming the tubing, in particular as the result of the action of the enzymes known as cellulases.
Another object of the invention resides in providing a method for manufacturing such a packaging material, particularly in the form of a tubular sausage casing.
In accomplishing the foregoing objects, there has been provided in accordance with one aspect of the present invention a tubular packaging material, preferably a sausage casing, comprising a carrier tubing comprised of cellulose hydrate and containing in its wall from about 5 to 12% by weight of water and from about 18 to 28% by weight of a plasticizer for cellulose hydrate, in each instance relative to the total weight of the carrier tubing; and a coating on the inside and on the outside of the carrier tubing of a water-insoluble heat-cured synthetic condensation product comprised of urea/
formaldehyede, formaldehyde/melamine, epichloro-hydrin/polyamine or epichlorohydrin/polyamine/polyamide,wherein the carrier tubing is characterized by a swelling value in the range from about 80 to 120%, and the tubular packaging, after soaking in water at a temperature between about 40 to 50C for a period of about 30 minutes and subsequent cooling to about room temperature, is characterized by dimensions in the wet state which are about 2 to 6% greater than those before soaking in water. In one preferred embodiment, the carrier tubing is comprised of cellulose hydrate which has been chemically modified by means of an organic chemical compound which has at least two N-methylol groups in the molecule.
In accordance with another aspect of the present invention there has been provided a process for the manufacture of the foregoing packaging 1 1~0~9~
material comprising the steps of treating at least the outside surface of a plasticizer-containing tubing which is comprised of cellulose hydrate gel and T~hich has not yet been subjected to any preceding heat treatment, with a fluid containing a water-soluble pre-condensate comprising urea/formaldehyde, formalde-hyde/melamine, epichlorohydrin/polyamine or epichloro-hydrin/polyamine-polyamide; passing the treated tubing continuously along its longitudinal axis through a first heat-treating zone under conditions which permit shrinking and thus drying it, the effective temperature being in the range from about 70 to 90C at the be-ginning of the first heat-treating zone and being in the range of from about 100 to 130C at the end of the first heat-treating zone; remoistening the dried tubing; and passing the tubing continuously through a second heat-treating zone and thus drying it, wherein the speed of advance of the tubing at the outlet of the second heat-treating zone is equal to or at most
.
I-TS MANUFACTIJRE
-BACKGROUND OF THE IN~ENTION
_ _ _ The present invention relates to a tubular packaging material, in particular to a sausage casing having a cellulose hydrate-based carrier tubing bearing a water-insoluble condensation product on at least one side, and also to processes for its manu~acture and to the use of the packaging material.
When artificial sausage casings are used in accordance with their i.ntended purposes, they are usually soaked in water before they are filled with a sausage emulsion, in order to provide them with the suppleness which is a pre-condition for filling the casings with a sausage emulsion without causing damage. For soaking in water, water at a temperature of about ~0 to 50C is allowed to act on the casings for a period of about 30 minutes.
In the manufacture of artificial sausage casings based on cellulose hydrate (U.S. Patent ~.
1 1~08~
No, 2,999,757), the tubing of cellulose hydrate gel is dried under conditions under which the tubing volume increases. In the case of these tubular casings, the surface area decreases during the soaking in water, before they are used in accordance with their intended purpose, by about 3 to 6%, relative to the area before soaking in water. The tubular casings which have been soaked in water and shrunk in this manner are then filled in the known manner with a sausage emulsion, by forcing the latter into the tubular casing which is closed at one end, and then sealing the other end of the casing.
SUM~RY OF THE INVENTION
It is an object of the present invention to provide an improved tubular packaging material which can be used as an artificial sausage casing for sausage preserves, and which is composed of a carrier tubing based on cellulose hydrate and on the wall of which a water-insoluble heat-cured synthetic condensation product is present.
It is another object of the invention to provide such a packaging material wherein a tubular packaging casing initially increases its dimensions, due to soaking in water before it is used in accord-ance with its intended purpose, and subsequently makesclose contact witK the filling after it has been filled with a sausage emulsion and dried.
It is also an object of the invention to provide a packaging material wherein, due to the structural and chemical composition of the packaging material and the structural properties of the carrier tubing, the material is substantially resistant to an enzymatically caused degradation of the cellulose hydrate molecules forming the tubing, in particular as the result of the action of the enzymes known as cellulases.
Another object of the invention resides in providing a method for manufacturing such a packaging material, particularly in the form of a tubular sausage casing.
In accomplishing the foregoing objects, there has been provided in accordance with one aspect of the present invention a tubular packaging material, preferably a sausage casing, comprising a carrier tubing comprised of cellulose hydrate and containing in its wall from about 5 to 12% by weight of water and from about 18 to 28% by weight of a plasticizer for cellulose hydrate, in each instance relative to the total weight of the carrier tubing; and a coating on the inside and on the outside of the carrier tubing of a water-insoluble heat-cured synthetic condensation product comprised of urea/
formaldehyede, formaldehyde/melamine, epichloro-hydrin/polyamine or epichlorohydrin/polyamine/polyamide,wherein the carrier tubing is characterized by a swelling value in the range from about 80 to 120%, and the tubular packaging, after soaking in water at a temperature between about 40 to 50C for a period of about 30 minutes and subsequent cooling to about room temperature, is characterized by dimensions in the wet state which are about 2 to 6% greater than those before soaking in water. In one preferred embodiment, the carrier tubing is comprised of cellulose hydrate which has been chemically modified by means of an organic chemical compound which has at least two N-methylol groups in the molecule.
In accordance with another aspect of the present invention there has been provided a process for the manufacture of the foregoing packaging 1 1~0~9~
material comprising the steps of treating at least the outside surface of a plasticizer-containing tubing which is comprised of cellulose hydrate gel and T~hich has not yet been subjected to any preceding heat treatment, with a fluid containing a water-soluble pre-condensate comprising urea/formaldehyde, formalde-hyde/melamine, epichlorohydrin/polyamine or epichloro-hydrin/polyamine-polyamide; passing the treated tubing continuously along its longitudinal axis through a first heat-treating zone under conditions which permit shrinking and thus drying it, the effective temperature being in the range from about 70 to 90C at the be-ginning of the first heat-treating zone and being in the range of from about 100 to 130C at the end of the first heat-treating zone; remoistening the dried tubing; and passing the tubing continuously through a second heat-treating zone and thus drying it, wherein the speed of advance of the tubing at the outlet of the second heat-treating zone is equal to or at most
2% greater than that at the inlet to the second heat-treating zone.
According to another embodiment of the process of the invention, the process comprises the steps of treating both the outside and the inside surface of the plasticizer-containing tubing with a fluid containiny the water-soluble pre-condensate; and subjecting the treated tubing to a single heat-treat-ment under conditions which permit shrinking of the tubing, the temperature prevailing during heat-treat-ment being sufficient to form the water-insoluble, heat-cured synthetic condensation product from the pre-condensate and to dry the tubing. When the tubing does not contain a cross-linking agent, the temperature at the beginning of the heat-treatment 35 is in the range from about 90 to 110C and the tem-perature prevailing at the end of the heat-treatment is in the range from about 140 to 160C. On the ~ 170~98 other hand if the tubing contains in its wall a chemical agent containing at least two N-methylol groups in the molecule for cross-linking the cellulose hydrate molecules, the tubing is subjected at the beginning of the heat-treatment to a temperature in the range of from about 70 to 90C and at the end of the heat-treatment to a temperature in the range of from about 100 to 130C.
In accordance with still another aspect of the invention, there has been provided a sausage casing compricing the tubular packaging material de-fined above1 as well as a sausage product further comprising a sausage filling contained inside of the casing.
Further objects, features and advantages of the present invention will become apparent from the detailed description of preferred embodiments which follows.
117089~
DETAILED DESCRIPTION OF PP~EFERRED EMBODIr~ENTS
The carrier tubing based on cellulose hydrate is preferably fiber-reinforced. Advantageously, the fiber-reinforcement consists of a fiber web, particu-larly preferably a paper fiber web, incorporated inthe tubing wall. The carrier tubing can also re-present a paper fiber web which is impregnated with cellulose hydrate, with a fiber-free cellulose hydrate coating being present on the outside.
The term carrier tubing based on cellulose hydrate also includes types of carrier tubing which are composed of chemically modified cellulose hydrate and are preferably fiber-reinforced.
The feature characterizing chemically modi-fied cellulose hydrate is that the cellulose hydrate molecules are mutually cross-linked by polyfunctional organic chemical compounds. The chemical cross-linking of the cellulose hydrate molecules is effected by a chemical cross-linking agent which contains at least two reactive ~J-methylol groups in the molecule, which are capable of reacting with thereactive groups of cellulose hydrate molecules. Cyclic urea compounds having at least two N-methylol groups in the molecule, for example, the following cyclic urea derivatives described in U.S. Patent No. 3,937,672 as chemical compounds for cross-linking cellulose hydrate molecules, are particularly suitable: dimethylol ethylene-urea (1,3-dimethylolimidazolid-2-one); dimethylol-dihydroxy-ethylene-urea (1,3-dimethylol-4,5-dihydroxy-imidazolid-2-one); dimethylol-ethyl-triazinone; 3,5-dimethylol-
According to another embodiment of the process of the invention, the process comprises the steps of treating both the outside and the inside surface of the plasticizer-containing tubing with a fluid containiny the water-soluble pre-condensate; and subjecting the treated tubing to a single heat-treat-ment under conditions which permit shrinking of the tubing, the temperature prevailing during heat-treat-ment being sufficient to form the water-insoluble, heat-cured synthetic condensation product from the pre-condensate and to dry the tubing. When the tubing does not contain a cross-linking agent, the temperature at the beginning of the heat-treatment 35 is in the range from about 90 to 110C and the tem-perature prevailing at the end of the heat-treatment is in the range from about 140 to 160C. On the ~ 170~98 other hand if the tubing contains in its wall a chemical agent containing at least two N-methylol groups in the molecule for cross-linking the cellulose hydrate molecules, the tubing is subjected at the beginning of the heat-treatment to a temperature in the range of from about 70 to 90C and at the end of the heat-treatment to a temperature in the range of from about 100 to 130C.
In accordance with still another aspect of the invention, there has been provided a sausage casing compricing the tubular packaging material de-fined above1 as well as a sausage product further comprising a sausage filling contained inside of the casing.
Further objects, features and advantages of the present invention will become apparent from the detailed description of preferred embodiments which follows.
117089~
DETAILED DESCRIPTION OF PP~EFERRED EMBODIr~ENTS
The carrier tubing based on cellulose hydrate is preferably fiber-reinforced. Advantageously, the fiber-reinforcement consists of a fiber web, particu-larly preferably a paper fiber web, incorporated inthe tubing wall. The carrier tubing can also re-present a paper fiber web which is impregnated with cellulose hydrate, with a fiber-free cellulose hydrate coating being present on the outside.
The term carrier tubing based on cellulose hydrate also includes types of carrier tubing which are composed of chemically modified cellulose hydrate and are preferably fiber-reinforced.
The feature characterizing chemically modi-fied cellulose hydrate is that the cellulose hydrate molecules are mutually cross-linked by polyfunctional organic chemical compounds. The chemical cross-linking of the cellulose hydrate molecules is effected by a chemical cross-linking agent which contains at least two reactive ~J-methylol groups in the molecule, which are capable of reacting with thereactive groups of cellulose hydrate molecules. Cyclic urea compounds having at least two N-methylol groups in the molecule, for example, the following cyclic urea derivatives described in U.S. Patent No. 3,937,672 as chemical compounds for cross-linking cellulose hydrate molecules, are particularly suitable: dimethylol ethylene-urea (1,3-dimethylolimidazolid-2-one); dimethylol-dihydroxy-ethylene-urea (1,3-dimethylol-4,5-dihydroxy-imidazolid-2-one); dimethylol-ethyl-triazinone; 3,5-dimethylol-
3,5-diaza-tetrahydropyr-4-one; tetramethylol-acetylene-diurea; dimethylol-propylene-urea; dimethylol-hydroxy-propylene-urea; dimethylol-tetramethyl-propylene-urea;
and the 2-dimethylolcarbamate of glycol l-monomethyl ~ 170898 ether. The chemically modified cellulose hydrate contains the said, preferably polyfunctional chemical compounds in a quantity within the range from about 0.5 to 5% by weight, for example, 2% by weight, relative to the weight of cellulose hydrate.
The process for chemically modifying cellulose hydrate with the aid of the said chemical compolmds is also described in the above-cited United States patent.
The cellulose hydrate, or chemically modified cellulose hydrate, form-ing the carrier tubing of the product has a swelling value (water-retention capacity) in the range of from about 80 to 120%, advantageously from about 80 to 115%, in particular from about 80 to 105%, and with very particular advantage from about 90 to 100%. To obtain the success desired according to the invention, it is essential that the swelling value of the cellulose hydrate forming the carrier tubing is smaller than about 120%, and in particular not greater than about 115%.
The swelling value indicates that quantity of water or queous solution in percent by weight, relative to the weight of the cellulose hydrate or chem-ically modified cellulose hydrate forming the carrier tubing, which can be bound by the material of the carrier tubing.
The swelling value is determined according to DIN 53,81~, described in "Faerberei- und textil~echnische Untersuchungen (Investigations in Dyeing and Textile Technology)", A. Agster, page ~50, Springer-Verlag, ]967, 10th edition.
Due to the low swelling value, the carrier tubing has a high dimensional stability when wet from soaking water. The cellulose hydrate or chemically ~, 1 ~7~8~
modified cellulose hydrate forming the carrier tubing is characterized by a consolidated molecular structure.
These ~roperties are due to a high proportion of crystalline zones, as compared with known tubing of this gener~l type, and in some cases these properties are due to chemical linking of cellulose hydrate mole-cules. These are preconditions for the product having the properties desired according to the invention.
When the product is used in accordance with its in-tended purpose as an artificial sausage casing forcooked sausages or boiling sausages, these properties lead to the desired effect. Sausage preserves are to be understood as uncooked sausages, such as, for example, cervelat sausage, gut sausage, salami, peppered salami, minced fat pork sausage, minced ham sausage, cottage-smoked sausage or smoked sausage spread.
The low swelling value of the cellulose hydrate forming the carrier tubing is an expression of the fact that the tubing comprises a proportion of crystalline zones which is relatively large as compared with conventional tubular cellulose hydrate casings of the general type having a higher swelling value.
It is assumed that water or aqueous fluid is unable, or virtually unable, to penetrate into these crystalline zones of the tubing, so that enzymes which are eapable of chemically degrading cellulose hydrate molecules, in partieular cellulases, cannot penetrate, or virtually cannot penetrate, into these zones.
The tubing wall, that is to say the inner and outer surfaees of the packaging material, contains chemical condensation products which additionally protect cellulose hydrate molecules from chemical de-gradation by enzymes, in particular cellulases, in a quantity whieh is the result of the indicated manufac-ture of the earrier tubing.
1 17(~89~
The properties of the product according to the invention are consequently the result of a combina-tion of the two measures stated above.
To obtain the desired result, the chemical condensation product is advantageously present on the outside and on the inside of the carrier tubing. Since any condensation product which is present on the outside and Gn the inside partially covers the surface of the tubing, this contributes to the increase in resistance of the cellulose hydrate tubing to the attack of enzymes which degrade cellulose hydrate.
A negligibly thin layer composed of this con-densation product on the surface of the carrier tubing does not form on the tubing a barrier layer, which would impede the passage of water vapor or air.
The carrier tubing has a wall thickness which advantageously corresponds to a weight per unit area in the range from about 80 to 110 g/m2.
Upon soaking in water, the casing increases its surface area or its volume by extension in the direction of its longitudinal axis and in a radial direction in such away that the surface area or the volume is in the region of from about 2 to 6%, in particular from about 3 to 5%, larger than in the unsoaked state. Soaking in water is to be understood as subjecting the casing to the action of water of a temperature in a range from about 40 to 50C for a period of about 30 minutes, for example, by placing it into a trough filled with water.
To determine the changes in the dimensions of the product in the wet state after soaking in water, in comparison with the dimensions of the product be-fore soaking in water, a dry casing (wa-ter content from ~bout 5 to 12% by weight) of defined length and defined diameter is taken, for example, a piece of tubing of 10 cm length and 9 cm diameter, and the piece ~ ~7(~89~
of tubing is cut open along the longitud~nal axis. The rectangular two-dimensional structure obtained is soaked in a trough filled with water at, for example, 50C for 30 minutes. The two-dimensional structure is then taken from the li~uid, its area dimension is de-termined in the wet state and this is compared with its dimensions before soaking in water The wet state of the rectangular two-dimen-sional structure is to be understood as that state in which the particular specimen is immediately at the end of the action of water and after cooling to room temperature.
The determination of the dimensions of the two-dimensional structure soaked in water as indicated, while still in the wet state, makes it impossible for its dimensions to be reduced due to loss of water on drying.
The carrier tubing of the packaging material according to the invention has a total moisture content of from about 30 to 40% by weight, relative to its total weight, and it contains about 5 to 12~ by weight of water as well as about 18 to 28% by weight o~ a chemical compound, known to be capable of plasticizing cellulose hydrate, in the form of polyols, in particular glycol, polyglycol or glycerol, in each case relative to the total weight of the packaging material.
The wall of the tubing, that is to say at least the inner and outer surfaces of the carrier tubing, contains a heat-cured, water-insoluble, syn-thetic condensation product which is selected from the group comprising condensation products of urea and formaldehyde, of melamine and formaldehyde, and preferably of epichlorohydrin and a polyamine or polyamine-polyamide.
As already explained above, these condensation products in the wall of the tubing, in combination with :l~70s~a the particular physical structure of the cellulose hydrate forming the carrier tubing, protect the tubing from bacterially caused chemical degradation of cellu-lose hydrate molecules by micro-organisms, for example, by cellulases.
As a result of the manufacturing process, a layer of one of these con-densation products is present on the outside of the tubing. The thickness of this layer, in comparison with the wall of thickness of the carrier tubing based on preferably fiber-reinforced cellulose hydrate, is negligibly small and does not make any significant contribution to the dimensional stability. For example, the layer has a thickness corresponding to a weight per unit area within the range from about 10 to 100 mg, for example, about 80 mg, of the said condensation product per m of substrate surface area. Cellulose hydrate tubing wherein the wall contains a protective laycr of a condensation product is described in United States Patent Number 3,378,379.
The invention comprises three variants of a process for the manufacture of a product of the structure described above.
The process variants are described below, by way of example.
PROCESS VARIANT I
The starting material for carrying out the first variant of the process according to the invention is a tubing which is composed of cellulose hydrate gel and which is prepared from viscose by coagulation and has not yet been sub-jected to any drying step. The wall of tubing contains a quantity of an aqueous solution of a chemical compound capable of plasticizing cellulose hydrate, this quantity corresponding to a swelling value of the cellulose hydrate gel, forming ~ ~0~8 the tubing, within the range from about 280 to 320~, for example about 300~.
The aqueous solution contains the plasticizer in a quantity within the range from about 8 to 12% by weight, advantageously about lO~ by weight, relative to its total weight.
Within the scope of the present description of the invention, the term "plasticizer for cellulose hydrate" comprises aliphatic polyhydroxy compounds, ln particular polyols, selected from the group comprising glycerol, glycol and polyglycol, for example, poly-glycol 2000.
The tubing of cellulose hydrate gel is, for example, fiber-reinforced and, advantageously, it has a paper fiber web incorporated into its wall.
These tubings per se and their manufacture form part of the state of the art.
The outer wall of the carrier tubing contains an impregnation which is composed of:
a) a water-soluble pre-condensate obtained from urea and formaldehyde, or b) a water-so]uble pre-condensate obtained from formaldehycle and melamine, or c) a watex-soluble pre-condensate obtained from epi-chlorohydrin and a polyamine or polyamine-polyamide.
These pre-condensates are heat-curable under the action of heat, being converted to water-insoluble condensation products.
1 ~0~98 In the heat-cured state, the reaction products are termed heat-cured, water-insoluble synthetic condensation products.
When carrying out the process, by way of example, a water-soluble pre-condensate obtained from epichlorohydrin and polyamine-polyamide is preferably present on the outside of the tubing of cellu]ose hydrate gel.
Water-soluble epichlorohydrin/polyamine/polyamide pre-condensates are described in United States Patent Number 2,926,154 and United States Patent Number 3,378,379 water soluble urea-formaldehyde pre-condensates are described in United States Patent Number 2,616,874, and water-soluble melamine/formaldehyde 10 pre-condensates are described in United States Patent Number 2,796,362 and United States Patent Number 2,345,543.
1 170~9 a The impregnation on the outside of the tubing of cellulose hydrate gel with the indicated chemical compounds is carried out, for example, by spraying the outside of the tubing with an aqueous fluid which con-tains one of the said pre-condensates or by passing the tubing, for example, continuously through a trough which is filled with an aqueous impregnation fluid. For example, the fluid is composed of an aqueous solution which contains about lO to 20 g/l, for example, 15 g/l, of dissolved epichlorohydrin/polyamine-polyamide pre-condensate. The impregnation fluid is brought into contact with the outside of the tubing by a method in - which such a quantity of the said fluid is applied to the surface of the tubing that the dissolved fraction thereof is present on the surface of the tubing in a quantity within the range of from about lO to lO0 mg/m2, for example, about 80 mg/m2.
To carry out the process, the tubing of cellu-lose hydrate gel having, for example, a diameter of90 mm is subjected continuously, while filled with sup-porting air, to a first heat treatment, during which no longitudinally acting tension force is allowed to affect the tubing, so that the particular integral section of tubing which is subjected to heat is able to shrink radially and longitudinally.
The pressure of the supporting air in the cavity of the tubing in the region of the zone of heat-treatment has a value, or is adjusted to a value, such that the tubing is capable of shrinking radially and longitudinally during the heat-treatment.
0~9 ~
The particular part of the tubing passing through the zone of heat~treatment is subjected at the beginning of the heat-treatment to a temperature within the range from about 70 to 90C and, in the final stages, to a temperature within the range from about 100 to 130C.
The total period during which the heat acts on the tubing is preferably about 1.5 to 3 minutes.
Passing the tubing without any tension along the longitudinal axis through the first heat-treatment zone is carried out in such a way that its speed of ad-vance within the heat-treatment zone is retarded.
Preferably, the speed of advance at the outlet of the tubing from the heat-treatment zone is about 2 to 10%, in particular about 3 to 6%, lower than that at the inlet to this zone. For example, the speed of advance of the tubing at the inlet to the heat treatment zone is lO m/minute, while the tubing at the outlet from the latter has a speed of advance of 9.5 m/minute.
After the tubing has left the first heat treatment zone, the water content in its wall is, for example, about 8 to 106 by weight, and its fraction of plasticizers is within the range from about 18 to 24%
by weight, in each case relative to the total weight of the tubing. After the first heat treatment, the tubing has a swelling value in the range between about 120 and 140~, for example, a swelling value of about 130~.
The first heat-treatment under the stated conditions can, for example, be accomplished as follows:
The tubing of cellulose hydrate gel, impreg-nated with pre-condensate on its outside and, if appropriate, on its inside, is continuously passed through a straight heatlng tunnel with a horizontally running longitudinal axis. The heating tunnel can, for example, also be equipped with electric heating elements which emit infrared radiation. The above-mentioned 08~8 retardation of the speed of advance of the tubing is effected in the heating tunnel, for example, by pressing the tubing flat together over its entire width, when it enters the heating tunnel, and advancing it at the same time toward the end of the heating tunnel. The flat-tening is effected, for example, by passing the tubing through the roll nip of a pair of squeeze rollers which is the first pair in the direction of advance of the tubing and which is located at the beginning of the heating tunnel, and the rollers of which are designed so that they can be rotated and driven. For example, the rollers are driven by motors.
In the region of the roll nip of the first pair of squeeze rollers, the outsides of the flat com-pressed tubing are in frictional contact with the peri-pheral surfaces of the driven roller of the first pair of squeeze rollers. The longitudinal advance of the tubing is accomplished by the frictional contact of its surfaces with the peripheral surfaces of the rotating rollers of the first pair of squeeze rollers.
The tubing issuing from the roll nip of the first pair of squeeze rollers is passed through the heating tunnel and then through the roll nip of a second pair of squeeze rollers, located at the end of the heating tunnel. The second pair of squeeze rollers ~ also has driven rollers. In the region of the roll nip of the second pair of squeeze rollers, the tubing is again compressed flat along a narrow zone. In the region of the roll nip of the second pair of squeeze rollers, the outside of the tubing is in frictional contact with the peripheral surfaces of the rollers of the second pair of squeeze rollers, each rotating at the same peripheral speed, whereby the tubing is de-livered out of the heating tunnel.
The peripheral speed of the driven rollers of the second pair of squeeze rollers is about 2 to 10%, preferably about 3 to 6%, for e~ample, about 4%, lower 1 17~8~
than the peripheral speed of the driven rollers of the first pair of squeeze rollers.
The peripheral speed of the driven rollers of the first pair of squeeze rollers is, for e~ample, about 10 m/minute, while the peripheral speed of the rollers of the second pair of squeeze rollers is about 9.5 m/minute. The particular speed at which the tubing is delivered by the pairs of squeeze rollers corresponds to the peripheral speeds of the rollers of the particu-lar pairs of rollers.
That part of the tubing which is located inthe region between the roll nip of the first pair of squeeze rollers and the nip of the second pair of squeeze rollers is filled with supporting air.
The first pair of squeeze rollers at the in-let of the heating tunnel is preferably arranged, relative to the second pair of squeeze rollers at the outlet of the heating tunnel, in such a way that the longitudinal axis of the common roll nip plane which can be laid through the roll nips of the pairs of squeeze rollers, virtually coincides with the straight longitudinal axis of the drying tunnel. The pairs of squeeze rollers are here advantageously arranged in such a way that the roll nip of the first pair of squeeze rollers is located immediately at the beginning, and the roll nip of the second pair of squeeze rollers is located immediately at the end of the heating tunnel.
The region between the roll nip of the first pair of squeeze rollers and that of the second pair of squeeze rollers is that zone within which the tubing of cellulose hydrate gel is for the first time subjected to heat.
The tubing which has for the first time been subjected to heat and dried under the conditions indic-ated, is then moistened thoroughly with water.
After moistening, the tubing contains in itswall a liquid fraction within the range of from about ~ 170~8 108 to 126% by weight, for example, about 117% by weight, relative to its total weight, wherein from about 8 to 12% by weight, for example, about 10% by weight, of the quantity of liquid in the tubing wall is constituted by plasticizers for cellulose hydrate, for example, glycerol.
The fraction of liquid in the tubing wall corresponds to the swelling value of the cellulose hydrate tubing.
The inside of the tubing is then coated with a fluid containing a pre-condensate, the qualitative and quantitative composition of this fluid correspond-ing to that of the fluid which has already been used for treating the outside of the tubing of cellulose hydrate gel. The coating of the inside of the tubing with the fluid can, for example, be carried out by means of the inside-coating technology described in United States Patent Number 3,378,379.
The tubing which has been moistened as indicated and, if appropriate, treated on its inside with a fluid containing a pre-condensate, is then sub-jected to a second heat-treatment and is thus dried.
During the second heat-treatment, the tubing is passed along its long-itudinal axis continuously at a substantailly constant speed through a heat-treating zone. Thus, the speeds of advance of the tubing at the inlet to the heat-treatment zone and the outlet from this zone are equal, or the speed at the outlet is only slightly greator, at most about 2%, for example, about l%, greater than the speed at the inlet to this zone.
Each part of the tubing is here subjected to the action of heat for a total period within the range from about 1.5 to 3 minutes.
The temperature during the second heat-treatment increases in the heat-treating zone in the direction 1 1708~
of advance of the tubing, and it is about 70 to 90C, for example, about 80C at the beginning of the zone and, at the end thereof, it is about 100 to 130C, for example, about 120C. After the second heat-treatment, S the tubing has a swelling value within the range from about 90 to 115%, for example, about 95%.
The second heat-treatment and the drying of the tubing is accordingly car~ied out while maintaining the temperatures indicated above, and the duration of 1~ heat-treatment corresponds to that which is used when carrying out the first drying. During the second dry-ing, however, the peripheral speeds of the rollers of the first pair of squeeze rollers are equal to the peri-pheral speeds of the rollers of the second pair of squeeze rollers. The peripheral speeds of the rollers of the pairs of squeeze rollers are, for example, about 10 m/minute~ The peripheral speed of the rollers of the second paix of squeeze rollers can, however, also be slightly, at most about 2%, for example, about 1%, greater than that of the rollers of the first pair of squeeze rollers. The speed of advance of the tubing on leaving the xoll nip of each pair of squeeze rollers thus corresponds to the peripheral speed of the squeeze rollers and, at the outlet from the roll nip of the second pair of squeeze rollers, is equal to or at most about 2%, for example, about 1%, greater than that at the outlet from the nip of the first pair of squeeze rollers.
~ 1~0898 The dried tubing has a water content within the range from 5 to 12% by weight, for example, about 10% by weight, relative to its total weight.
If appropriate, the tubing is moistened with water in order to produce a defined final water content of about 5 to 12% by weight, for example, a~out 10% by weight, relative to the total weight of the tubing, in the wall of the tubing.
To moisten the tubing with water it is passed, for example, continuously through a trough filled with water.
~ :a7~9~
The shrinking behavior of the packaging material after soaking in water, when it is used in accordance with its intended purpose as a sausage casing, is governed essentially by the particular manner of passing the tubing through the heat_treating zone during the first heat-treatment of the tubing.
The low swelling value of the packaging material, as intended according to the invention, results from the combined special thermal conditions under which the first and second heat-treatments are carried out.
PROCESS VARIANT II
The second variant of the process according to the invention is explained in the following text, by way of example.
The starting material is, for example, a fiber-reinforced tubing which is composed of cellulose hydrate gel and has not been subjected to any prior heat treatment and has a swelling value in the range from about 280 to 320% by weight, for example, about 300% by weight. In the wall o~ the tubing, a quantity of an aqueous solution corresponding to the swelling value of the cellulose hydrate gel is present which contains plasticizers for cellulose hydrate, for example, glycerol, and an organic chemical compound which has at least two N-methylol groups in the mole-cule and is selected from a group of chemical compounds comprising cyclic urea compounds having two N-methylol groups in the molecule, for example, dimethyloldihydroxy-ethylene-urea (1,3-dimethylol-4,5-dihydroxy-imidazolin-2-one).
As the primary plasticizer, the aqueous solu-tion contains glycerol in a quantity within the range 35 from about 8 to 12% by weight, for example, about 10%
by weight. The aqueous solution contains the bi-functional compounds which are capable of chemically 1 1~08g8 linking cellulose hydrate, which have a-t least two N-methylol groups in the molecule and which are selected from the group comprising the chemical compounds in-dicated a~ove, in a quantity within the range from about 0.5 to 5% by weight, for example, about 2.5%
by weight, relative to the weight of the aqueous solution. The bifunctional chemical compounds, as indicated above, are described in U.S. Patent No.
3,937,672.
The tubing contains the bifunctional chemical compounds having at least two N-methylol groups in the molecule, in a quantity of, for example, about 1 to 3%
by weight, relative to the total weight of the cellulose hydrate in the tubing.
This precursor of the process product is obtained, for example, by causing an aqueous fluid which contains a compound capable of plasticizing cellulose hydrate, for example, glycerol, in a quantity withinthe range from about 5 to 12% by weight, for example, about 10% by weight, relative to its total weight, to act on the preferably fiber-reinforced tubing of cellulose hydrate gel, which has been pre-pared from viscose by coagulation and which has not yet been dried. Additionally, this solution contalns an organic-chemical compound having at least two N-methylol groups in the molecule, for example, di-methyloldihydroxyethylene-urea, in a quantity within the range from about 0.5 to 5% by weight, in particular, from about 1.5 to 3% by weight, relative to the total weight of the solution.
To carry out this plasticizer treatment, the tubing of cellulose hydrate gel is passed continuously through a trough filled with the fluid.
The outside and inside of the tubing treated as above are then each treated with a fluid which contains a water-soluble pre-condensate, and the ~ 17089~
composition of which was described in connection with the first process variant. The treatment is carried out, for example, as indicated for the first process variant.
The tubing of cellulose hydrate gel is then subjected to the action of heat and is dried, with the same conditions, in particular with respect to tempera-ture, speed of the tubing and time of the action of heat, being maintained as during the first heat-treat-ment according to the first process variant.
After this heat treatment, the tubing already has a swelling value in the range from about 90 to 115%, for example, about 100%.
If appropriate, the tubing is moistened with water in the same way as indicated in the explanation of the first process variant.
~l7vssa The desired shrinking behavior of the packaging material after soaking in water, when it i5 used in accordance with its intended purpose, is governed by the particular manner of passing the tubing through the heat-treatment zone, under con-ditions which permit shrinking of the tubing.
The low swelling value, desired according to the invention, of the process product is a con-sequence of the chemical structure of the carrier tubing. During the heat treatment, the cellulose hydrate molecules of the tubing are chemically linked by the bifunctional chemical compound in the tubing wall, whereby a low swelling value of the tubing is achieved.
PROCESS VARIANT III
_ The way in which the third variant of the process according to the invention is carried out differs from that in which the second variant of the process is carried out, in the following points:
1. The starting tubing corresponds to the cellulose hydrate gel of process variant I, that is to say i-t is not chemically modified. Its outer and inner surfaces have been treated with a fluid containing a plasticizer and with a fluid con-taining a pre-condensate.
2. The heat treatment on the tubing has a temperature in the range from about 90 to 110C, preferably about 100C, at the beginning of the hea-t-treatment zone and, at the end, has a temperature in the range from about 140 to 160C, preferably about 150C.
The tubing is subjected to the action of heat for a total period in the range from about 3 to 8 minutes, for example, about 6 minutes. The action of heat is effected analogously to process variant I, under conditions which permit shrinkage of the tubing.
1 17083~
After the heat-treatment, the tubing has a swelling value in the range from about 90 to 115%, for example, 100~. A second heat treatment is not necessary.
~he low swelling value and the shrinking behavior of the packaying material manufactured by the third process variant, when it is used in accord-ance with its intended purpose as a sausage casing, are governed by the special heat treatment.
In the three process variants for the manufacture of the packaging material, the essential point of the first process variant is that the starting tubing is initially subjected to the in-dicated first thermal treatment, for a defined duration of the action of heat and at a defined temperature, under conditions which permit shrinking, whereupon it is moistened and is subsequently subjected under conditions virtually free from tension to a second heat treatment under the in dicated conditions, whereby the swelling value of the cellulose hydrate constituting the tubing is reduced in each case from an initial value to an end value which is lower by comparison, during each of the two heat treatment steps. The initial swelling value of the tubing at the beginning of the second heat-treating step corresponds to the swelllng value of the tubing after the first heat treatment.
When the second process variant is carried out, it is essential for the properties of the product according to the invention, that the starting tubing is composed of a chemically modified cellulose hydrate and the tubing is subjected to -the single heat treat-ment under conditions which permit shrinking, at the stated temperatures and periods of heating.
For the effect intended by the invention to occur, it is essential when carrying out the third ~oa~8 process variant, that the starting tubing of the indicated chemical structure is subjected to the single intense heat treatment under conditions which permit shrinking.
and the 2-dimethylolcarbamate of glycol l-monomethyl ~ 170898 ether. The chemically modified cellulose hydrate contains the said, preferably polyfunctional chemical compounds in a quantity within the range from about 0.5 to 5% by weight, for example, 2% by weight, relative to the weight of cellulose hydrate.
The process for chemically modifying cellulose hydrate with the aid of the said chemical compolmds is also described in the above-cited United States patent.
The cellulose hydrate, or chemically modified cellulose hydrate, form-ing the carrier tubing of the product has a swelling value (water-retention capacity) in the range of from about 80 to 120%, advantageously from about 80 to 115%, in particular from about 80 to 105%, and with very particular advantage from about 90 to 100%. To obtain the success desired according to the invention, it is essential that the swelling value of the cellulose hydrate forming the carrier tubing is smaller than about 120%, and in particular not greater than about 115%.
The swelling value indicates that quantity of water or queous solution in percent by weight, relative to the weight of the cellulose hydrate or chem-ically modified cellulose hydrate forming the carrier tubing, which can be bound by the material of the carrier tubing.
The swelling value is determined according to DIN 53,81~, described in "Faerberei- und textil~echnische Untersuchungen (Investigations in Dyeing and Textile Technology)", A. Agster, page ~50, Springer-Verlag, ]967, 10th edition.
Due to the low swelling value, the carrier tubing has a high dimensional stability when wet from soaking water. The cellulose hydrate or chemically ~, 1 ~7~8~
modified cellulose hydrate forming the carrier tubing is characterized by a consolidated molecular structure.
These ~roperties are due to a high proportion of crystalline zones, as compared with known tubing of this gener~l type, and in some cases these properties are due to chemical linking of cellulose hydrate mole-cules. These are preconditions for the product having the properties desired according to the invention.
When the product is used in accordance with its in-tended purpose as an artificial sausage casing forcooked sausages or boiling sausages, these properties lead to the desired effect. Sausage preserves are to be understood as uncooked sausages, such as, for example, cervelat sausage, gut sausage, salami, peppered salami, minced fat pork sausage, minced ham sausage, cottage-smoked sausage or smoked sausage spread.
The low swelling value of the cellulose hydrate forming the carrier tubing is an expression of the fact that the tubing comprises a proportion of crystalline zones which is relatively large as compared with conventional tubular cellulose hydrate casings of the general type having a higher swelling value.
It is assumed that water or aqueous fluid is unable, or virtually unable, to penetrate into these crystalline zones of the tubing, so that enzymes which are eapable of chemically degrading cellulose hydrate molecules, in partieular cellulases, cannot penetrate, or virtually cannot penetrate, into these zones.
The tubing wall, that is to say the inner and outer surfaees of the packaging material, contains chemical condensation products which additionally protect cellulose hydrate molecules from chemical de-gradation by enzymes, in particular cellulases, in a quantity whieh is the result of the indicated manufac-ture of the earrier tubing.
1 17(~89~
The properties of the product according to the invention are consequently the result of a combina-tion of the two measures stated above.
To obtain the desired result, the chemical condensation product is advantageously present on the outside and on the inside of the carrier tubing. Since any condensation product which is present on the outside and Gn the inside partially covers the surface of the tubing, this contributes to the increase in resistance of the cellulose hydrate tubing to the attack of enzymes which degrade cellulose hydrate.
A negligibly thin layer composed of this con-densation product on the surface of the carrier tubing does not form on the tubing a barrier layer, which would impede the passage of water vapor or air.
The carrier tubing has a wall thickness which advantageously corresponds to a weight per unit area in the range from about 80 to 110 g/m2.
Upon soaking in water, the casing increases its surface area or its volume by extension in the direction of its longitudinal axis and in a radial direction in such away that the surface area or the volume is in the region of from about 2 to 6%, in particular from about 3 to 5%, larger than in the unsoaked state. Soaking in water is to be understood as subjecting the casing to the action of water of a temperature in a range from about 40 to 50C for a period of about 30 minutes, for example, by placing it into a trough filled with water.
To determine the changes in the dimensions of the product in the wet state after soaking in water, in comparison with the dimensions of the product be-fore soaking in water, a dry casing (wa-ter content from ~bout 5 to 12% by weight) of defined length and defined diameter is taken, for example, a piece of tubing of 10 cm length and 9 cm diameter, and the piece ~ ~7(~89~
of tubing is cut open along the longitud~nal axis. The rectangular two-dimensional structure obtained is soaked in a trough filled with water at, for example, 50C for 30 minutes. The two-dimensional structure is then taken from the li~uid, its area dimension is de-termined in the wet state and this is compared with its dimensions before soaking in water The wet state of the rectangular two-dimen-sional structure is to be understood as that state in which the particular specimen is immediately at the end of the action of water and after cooling to room temperature.
The determination of the dimensions of the two-dimensional structure soaked in water as indicated, while still in the wet state, makes it impossible for its dimensions to be reduced due to loss of water on drying.
The carrier tubing of the packaging material according to the invention has a total moisture content of from about 30 to 40% by weight, relative to its total weight, and it contains about 5 to 12~ by weight of water as well as about 18 to 28% by weight o~ a chemical compound, known to be capable of plasticizing cellulose hydrate, in the form of polyols, in particular glycol, polyglycol or glycerol, in each case relative to the total weight of the packaging material.
The wall of the tubing, that is to say at least the inner and outer surfaces of the carrier tubing, contains a heat-cured, water-insoluble, syn-thetic condensation product which is selected from the group comprising condensation products of urea and formaldehyde, of melamine and formaldehyde, and preferably of epichlorohydrin and a polyamine or polyamine-polyamide.
As already explained above, these condensation products in the wall of the tubing, in combination with :l~70s~a the particular physical structure of the cellulose hydrate forming the carrier tubing, protect the tubing from bacterially caused chemical degradation of cellu-lose hydrate molecules by micro-organisms, for example, by cellulases.
As a result of the manufacturing process, a layer of one of these con-densation products is present on the outside of the tubing. The thickness of this layer, in comparison with the wall of thickness of the carrier tubing based on preferably fiber-reinforced cellulose hydrate, is negligibly small and does not make any significant contribution to the dimensional stability. For example, the layer has a thickness corresponding to a weight per unit area within the range from about 10 to 100 mg, for example, about 80 mg, of the said condensation product per m of substrate surface area. Cellulose hydrate tubing wherein the wall contains a protective laycr of a condensation product is described in United States Patent Number 3,378,379.
The invention comprises three variants of a process for the manufacture of a product of the structure described above.
The process variants are described below, by way of example.
PROCESS VARIANT I
The starting material for carrying out the first variant of the process according to the invention is a tubing which is composed of cellulose hydrate gel and which is prepared from viscose by coagulation and has not yet been sub-jected to any drying step. The wall of tubing contains a quantity of an aqueous solution of a chemical compound capable of plasticizing cellulose hydrate, this quantity corresponding to a swelling value of the cellulose hydrate gel, forming ~ ~0~8 the tubing, within the range from about 280 to 320~, for example about 300~.
The aqueous solution contains the plasticizer in a quantity within the range from about 8 to 12% by weight, advantageously about lO~ by weight, relative to its total weight.
Within the scope of the present description of the invention, the term "plasticizer for cellulose hydrate" comprises aliphatic polyhydroxy compounds, ln particular polyols, selected from the group comprising glycerol, glycol and polyglycol, for example, poly-glycol 2000.
The tubing of cellulose hydrate gel is, for example, fiber-reinforced and, advantageously, it has a paper fiber web incorporated into its wall.
These tubings per se and their manufacture form part of the state of the art.
The outer wall of the carrier tubing contains an impregnation which is composed of:
a) a water-soluble pre-condensate obtained from urea and formaldehyde, or b) a water-so]uble pre-condensate obtained from formaldehycle and melamine, or c) a watex-soluble pre-condensate obtained from epi-chlorohydrin and a polyamine or polyamine-polyamide.
These pre-condensates are heat-curable under the action of heat, being converted to water-insoluble condensation products.
1 ~0~98 In the heat-cured state, the reaction products are termed heat-cured, water-insoluble synthetic condensation products.
When carrying out the process, by way of example, a water-soluble pre-condensate obtained from epichlorohydrin and polyamine-polyamide is preferably present on the outside of the tubing of cellu]ose hydrate gel.
Water-soluble epichlorohydrin/polyamine/polyamide pre-condensates are described in United States Patent Number 2,926,154 and United States Patent Number 3,378,379 water soluble urea-formaldehyde pre-condensates are described in United States Patent Number 2,616,874, and water-soluble melamine/formaldehyde 10 pre-condensates are described in United States Patent Number 2,796,362 and United States Patent Number 2,345,543.
1 170~9 a The impregnation on the outside of the tubing of cellulose hydrate gel with the indicated chemical compounds is carried out, for example, by spraying the outside of the tubing with an aqueous fluid which con-tains one of the said pre-condensates or by passing the tubing, for example, continuously through a trough which is filled with an aqueous impregnation fluid. For example, the fluid is composed of an aqueous solution which contains about lO to 20 g/l, for example, 15 g/l, of dissolved epichlorohydrin/polyamine-polyamide pre-condensate. The impregnation fluid is brought into contact with the outside of the tubing by a method in - which such a quantity of the said fluid is applied to the surface of the tubing that the dissolved fraction thereof is present on the surface of the tubing in a quantity within the range of from about lO to lO0 mg/m2, for example, about 80 mg/m2.
To carry out the process, the tubing of cellu-lose hydrate gel having, for example, a diameter of90 mm is subjected continuously, while filled with sup-porting air, to a first heat treatment, during which no longitudinally acting tension force is allowed to affect the tubing, so that the particular integral section of tubing which is subjected to heat is able to shrink radially and longitudinally.
The pressure of the supporting air in the cavity of the tubing in the region of the zone of heat-treatment has a value, or is adjusted to a value, such that the tubing is capable of shrinking radially and longitudinally during the heat-treatment.
0~9 ~
The particular part of the tubing passing through the zone of heat~treatment is subjected at the beginning of the heat-treatment to a temperature within the range from about 70 to 90C and, in the final stages, to a temperature within the range from about 100 to 130C.
The total period during which the heat acts on the tubing is preferably about 1.5 to 3 minutes.
Passing the tubing without any tension along the longitudinal axis through the first heat-treatment zone is carried out in such a way that its speed of ad-vance within the heat-treatment zone is retarded.
Preferably, the speed of advance at the outlet of the tubing from the heat-treatment zone is about 2 to 10%, in particular about 3 to 6%, lower than that at the inlet to this zone. For example, the speed of advance of the tubing at the inlet to the heat treatment zone is lO m/minute, while the tubing at the outlet from the latter has a speed of advance of 9.5 m/minute.
After the tubing has left the first heat treatment zone, the water content in its wall is, for example, about 8 to 106 by weight, and its fraction of plasticizers is within the range from about 18 to 24%
by weight, in each case relative to the total weight of the tubing. After the first heat treatment, the tubing has a swelling value in the range between about 120 and 140~, for example, a swelling value of about 130~.
The first heat-treatment under the stated conditions can, for example, be accomplished as follows:
The tubing of cellulose hydrate gel, impreg-nated with pre-condensate on its outside and, if appropriate, on its inside, is continuously passed through a straight heatlng tunnel with a horizontally running longitudinal axis. The heating tunnel can, for example, also be equipped with electric heating elements which emit infrared radiation. The above-mentioned 08~8 retardation of the speed of advance of the tubing is effected in the heating tunnel, for example, by pressing the tubing flat together over its entire width, when it enters the heating tunnel, and advancing it at the same time toward the end of the heating tunnel. The flat-tening is effected, for example, by passing the tubing through the roll nip of a pair of squeeze rollers which is the first pair in the direction of advance of the tubing and which is located at the beginning of the heating tunnel, and the rollers of which are designed so that they can be rotated and driven. For example, the rollers are driven by motors.
In the region of the roll nip of the first pair of squeeze rollers, the outsides of the flat com-pressed tubing are in frictional contact with the peri-pheral surfaces of the driven roller of the first pair of squeeze rollers. The longitudinal advance of the tubing is accomplished by the frictional contact of its surfaces with the peripheral surfaces of the rotating rollers of the first pair of squeeze rollers.
The tubing issuing from the roll nip of the first pair of squeeze rollers is passed through the heating tunnel and then through the roll nip of a second pair of squeeze rollers, located at the end of the heating tunnel. The second pair of squeeze rollers ~ also has driven rollers. In the region of the roll nip of the second pair of squeeze rollers, the tubing is again compressed flat along a narrow zone. In the region of the roll nip of the second pair of squeeze rollers, the outside of the tubing is in frictional contact with the peripheral surfaces of the rollers of the second pair of squeeze rollers, each rotating at the same peripheral speed, whereby the tubing is de-livered out of the heating tunnel.
The peripheral speed of the driven rollers of the second pair of squeeze rollers is about 2 to 10%, preferably about 3 to 6%, for e~ample, about 4%, lower 1 17~8~
than the peripheral speed of the driven rollers of the first pair of squeeze rollers.
The peripheral speed of the driven rollers of the first pair of squeeze rollers is, for e~ample, about 10 m/minute, while the peripheral speed of the rollers of the second pair of squeeze rollers is about 9.5 m/minute. The particular speed at which the tubing is delivered by the pairs of squeeze rollers corresponds to the peripheral speeds of the rollers of the particu-lar pairs of rollers.
That part of the tubing which is located inthe region between the roll nip of the first pair of squeeze rollers and the nip of the second pair of squeeze rollers is filled with supporting air.
The first pair of squeeze rollers at the in-let of the heating tunnel is preferably arranged, relative to the second pair of squeeze rollers at the outlet of the heating tunnel, in such a way that the longitudinal axis of the common roll nip plane which can be laid through the roll nips of the pairs of squeeze rollers, virtually coincides with the straight longitudinal axis of the drying tunnel. The pairs of squeeze rollers are here advantageously arranged in such a way that the roll nip of the first pair of squeeze rollers is located immediately at the beginning, and the roll nip of the second pair of squeeze rollers is located immediately at the end of the heating tunnel.
The region between the roll nip of the first pair of squeeze rollers and that of the second pair of squeeze rollers is that zone within which the tubing of cellulose hydrate gel is for the first time subjected to heat.
The tubing which has for the first time been subjected to heat and dried under the conditions indic-ated, is then moistened thoroughly with water.
After moistening, the tubing contains in itswall a liquid fraction within the range of from about ~ 170~8 108 to 126% by weight, for example, about 117% by weight, relative to its total weight, wherein from about 8 to 12% by weight, for example, about 10% by weight, of the quantity of liquid in the tubing wall is constituted by plasticizers for cellulose hydrate, for example, glycerol.
The fraction of liquid in the tubing wall corresponds to the swelling value of the cellulose hydrate tubing.
The inside of the tubing is then coated with a fluid containing a pre-condensate, the qualitative and quantitative composition of this fluid correspond-ing to that of the fluid which has already been used for treating the outside of the tubing of cellulose hydrate gel. The coating of the inside of the tubing with the fluid can, for example, be carried out by means of the inside-coating technology described in United States Patent Number 3,378,379.
The tubing which has been moistened as indicated and, if appropriate, treated on its inside with a fluid containing a pre-condensate, is then sub-jected to a second heat-treatment and is thus dried.
During the second heat-treatment, the tubing is passed along its long-itudinal axis continuously at a substantailly constant speed through a heat-treating zone. Thus, the speeds of advance of the tubing at the inlet to the heat-treatment zone and the outlet from this zone are equal, or the speed at the outlet is only slightly greator, at most about 2%, for example, about l%, greater than the speed at the inlet to this zone.
Each part of the tubing is here subjected to the action of heat for a total period within the range from about 1.5 to 3 minutes.
The temperature during the second heat-treatment increases in the heat-treating zone in the direction 1 1708~
of advance of the tubing, and it is about 70 to 90C, for example, about 80C at the beginning of the zone and, at the end thereof, it is about 100 to 130C, for example, about 120C. After the second heat-treatment, S the tubing has a swelling value within the range from about 90 to 115%, for example, about 95%.
The second heat-treatment and the drying of the tubing is accordingly car~ied out while maintaining the temperatures indicated above, and the duration of 1~ heat-treatment corresponds to that which is used when carrying out the first drying. During the second dry-ing, however, the peripheral speeds of the rollers of the first pair of squeeze rollers are equal to the peri-pheral speeds of the rollers of the second pair of squeeze rollers. The peripheral speeds of the rollers of the pairs of squeeze rollers are, for example, about 10 m/minute~ The peripheral speed of the rollers of the second paix of squeeze rollers can, however, also be slightly, at most about 2%, for example, about 1%, greater than that of the rollers of the first pair of squeeze rollers. The speed of advance of the tubing on leaving the xoll nip of each pair of squeeze rollers thus corresponds to the peripheral speed of the squeeze rollers and, at the outlet from the roll nip of the second pair of squeeze rollers, is equal to or at most about 2%, for example, about 1%, greater than that at the outlet from the nip of the first pair of squeeze rollers.
~ 1~0898 The dried tubing has a water content within the range from 5 to 12% by weight, for example, about 10% by weight, relative to its total weight.
If appropriate, the tubing is moistened with water in order to produce a defined final water content of about 5 to 12% by weight, for example, a~out 10% by weight, relative to the total weight of the tubing, in the wall of the tubing.
To moisten the tubing with water it is passed, for example, continuously through a trough filled with water.
~ :a7~9~
The shrinking behavior of the packaging material after soaking in water, when it is used in accordance with its intended purpose as a sausage casing, is governed essentially by the particular manner of passing the tubing through the heat_treating zone during the first heat-treatment of the tubing.
The low swelling value of the packaging material, as intended according to the invention, results from the combined special thermal conditions under which the first and second heat-treatments are carried out.
PROCESS VARIANT II
The second variant of the process according to the invention is explained in the following text, by way of example.
The starting material is, for example, a fiber-reinforced tubing which is composed of cellulose hydrate gel and has not been subjected to any prior heat treatment and has a swelling value in the range from about 280 to 320% by weight, for example, about 300% by weight. In the wall o~ the tubing, a quantity of an aqueous solution corresponding to the swelling value of the cellulose hydrate gel is present which contains plasticizers for cellulose hydrate, for example, glycerol, and an organic chemical compound which has at least two N-methylol groups in the mole-cule and is selected from a group of chemical compounds comprising cyclic urea compounds having two N-methylol groups in the molecule, for example, dimethyloldihydroxy-ethylene-urea (1,3-dimethylol-4,5-dihydroxy-imidazolin-2-one).
As the primary plasticizer, the aqueous solu-tion contains glycerol in a quantity within the range 35 from about 8 to 12% by weight, for example, about 10%
by weight. The aqueous solution contains the bi-functional compounds which are capable of chemically 1 1~08g8 linking cellulose hydrate, which have a-t least two N-methylol groups in the molecule and which are selected from the group comprising the chemical compounds in-dicated a~ove, in a quantity within the range from about 0.5 to 5% by weight, for example, about 2.5%
by weight, relative to the weight of the aqueous solution. The bifunctional chemical compounds, as indicated above, are described in U.S. Patent No.
3,937,672.
The tubing contains the bifunctional chemical compounds having at least two N-methylol groups in the molecule, in a quantity of, for example, about 1 to 3%
by weight, relative to the total weight of the cellulose hydrate in the tubing.
This precursor of the process product is obtained, for example, by causing an aqueous fluid which contains a compound capable of plasticizing cellulose hydrate, for example, glycerol, in a quantity withinthe range from about 5 to 12% by weight, for example, about 10% by weight, relative to its total weight, to act on the preferably fiber-reinforced tubing of cellulose hydrate gel, which has been pre-pared from viscose by coagulation and which has not yet been dried. Additionally, this solution contalns an organic-chemical compound having at least two N-methylol groups in the molecule, for example, di-methyloldihydroxyethylene-urea, in a quantity within the range from about 0.5 to 5% by weight, in particular, from about 1.5 to 3% by weight, relative to the total weight of the solution.
To carry out this plasticizer treatment, the tubing of cellulose hydrate gel is passed continuously through a trough filled with the fluid.
The outside and inside of the tubing treated as above are then each treated with a fluid which contains a water-soluble pre-condensate, and the ~ 17089~
composition of which was described in connection with the first process variant. The treatment is carried out, for example, as indicated for the first process variant.
The tubing of cellulose hydrate gel is then subjected to the action of heat and is dried, with the same conditions, in particular with respect to tempera-ture, speed of the tubing and time of the action of heat, being maintained as during the first heat-treat-ment according to the first process variant.
After this heat treatment, the tubing already has a swelling value in the range from about 90 to 115%, for example, about 100%.
If appropriate, the tubing is moistened with water in the same way as indicated in the explanation of the first process variant.
~l7vssa The desired shrinking behavior of the packaging material after soaking in water, when it i5 used in accordance with its intended purpose, is governed by the particular manner of passing the tubing through the heat-treatment zone, under con-ditions which permit shrinking of the tubing.
The low swelling value, desired according to the invention, of the process product is a con-sequence of the chemical structure of the carrier tubing. During the heat treatment, the cellulose hydrate molecules of the tubing are chemically linked by the bifunctional chemical compound in the tubing wall, whereby a low swelling value of the tubing is achieved.
PROCESS VARIANT III
_ The way in which the third variant of the process according to the invention is carried out differs from that in which the second variant of the process is carried out, in the following points:
1. The starting tubing corresponds to the cellulose hydrate gel of process variant I, that is to say i-t is not chemically modified. Its outer and inner surfaces have been treated with a fluid containing a plasticizer and with a fluid con-taining a pre-condensate.
2. The heat treatment on the tubing has a temperature in the range from about 90 to 110C, preferably about 100C, at the beginning of the hea-t-treatment zone and, at the end, has a temperature in the range from about 140 to 160C, preferably about 150C.
The tubing is subjected to the action of heat for a total period in the range from about 3 to 8 minutes, for example, about 6 minutes. The action of heat is effected analogously to process variant I, under conditions which permit shrinkage of the tubing.
1 17083~
After the heat-treatment, the tubing has a swelling value in the range from about 90 to 115%, for example, 100~. A second heat treatment is not necessary.
~he low swelling value and the shrinking behavior of the packaying material manufactured by the third process variant, when it is used in accord-ance with its intended purpose as a sausage casing, are governed by the special heat treatment.
In the three process variants for the manufacture of the packaging material, the essential point of the first process variant is that the starting tubing is initially subjected to the in-dicated first thermal treatment, for a defined duration of the action of heat and at a defined temperature, under conditions which permit shrinking, whereupon it is moistened and is subsequently subjected under conditions virtually free from tension to a second heat treatment under the in dicated conditions, whereby the swelling value of the cellulose hydrate constituting the tubing is reduced in each case from an initial value to an end value which is lower by comparison, during each of the two heat treatment steps. The initial swelling value of the tubing at the beginning of the second heat-treating step corresponds to the swelllng value of the tubing after the first heat treatment.
When the second process variant is carried out, it is essential for the properties of the product according to the invention, that the starting tubing is composed of a chemically modified cellulose hydrate and the tubing is subjected to -the single heat treat-ment under conditions which permit shrinking, at the stated temperatures and periods of heating.
For the effect intended by the invention to occur, it is essential when carrying out the third ~oa~8 process variant, that the starting tubing of the indicated chemical structure is subjected to the single intense heat treatment under conditions which permit shrinking.
Claims (18)
1. A tubular packaging material, comprising:
a carrier tubing comprised of cellulose hydrate and containing in its wall from about 5 to 12%
by weight of water and from about 18 to 28% by weight of a plasticizer for cellulose hydrate, in each instance relative to the total weight of the carrier tubing; and a coating on the inside and on the out-side of said carrier tubing of a water-insoluble, heat-cured synthetic condensation product comprised of urea/formaldehyde, formaldehyde/melamine, epichloro-hydrin/polyamine or epichlorohydrin/polyamine/polyamide, wherein the carrier tubing is characterized by a swelling value in the range from about 80 to 120%, and the tubular packaging, after soaking in water at a temperature between about 40 to 50°C for a period of about 30 minutes and subsequent cooling to about room temperature, is characterized by dimensions in the wet state which are 2 to 6% greater than those before said soaking in water.
a carrier tubing comprised of cellulose hydrate and containing in its wall from about 5 to 12%
by weight of water and from about 18 to 28% by weight of a plasticizer for cellulose hydrate, in each instance relative to the total weight of the carrier tubing; and a coating on the inside and on the out-side of said carrier tubing of a water-insoluble, heat-cured synthetic condensation product comprised of urea/formaldehyde, formaldehyde/melamine, epichloro-hydrin/polyamine or epichlorohydrin/polyamine/polyamide, wherein the carrier tubing is characterized by a swelling value in the range from about 80 to 120%, and the tubular packaging, after soaking in water at a temperature between about 40 to 50°C for a period of about 30 minutes and subsequent cooling to about room temperature, is characterized by dimensions in the wet state which are 2 to 6% greater than those before said soaking in water.
2. A packaging material as claimed in Claim 1, wherein said carrier tubing is comprised of cellulose hydrate which has been chemically modified by means of an organic chemical compound which has at least two N-methylol groups in the molecule.
3. A process for the manufacture of a packaging material as claimed in Claim 1, comprising the steps of:
treating at least the outside surface of a plasticizer-containing tubing which is comprised of cellulose hydrate gel and which has not yet been subjected to any preceding heat treatment, with a fluid containing a water-soluble pre-condensate com-prising urea/formaldehyde, formaldehyde/melamine, epichlorohydrin/polyamine or epichlorohydrin/polyamine-polyamide; passing the treated tubing continuously along its longitudinal axis through a first heat-treating zone under conditions which permit shrinking and thus drying it, the effective temperature being in the range from about 70 to 90°C at the beginning of the first heat-treating zone and being in the range from about 100 to 130°C at the end of the first heat-treating zone; remoistening the dried tubing; and passing the tubing continuously through a second heat-treating zone and thus drying it, wherein the speed of advance of the tubing at the outlet of the second heat-treating zone is equal to or at most 2% greater than that at the inlet to the second heat-treating zone.
treating at least the outside surface of a plasticizer-containing tubing which is comprised of cellulose hydrate gel and which has not yet been subjected to any preceding heat treatment, with a fluid containing a water-soluble pre-condensate com-prising urea/formaldehyde, formaldehyde/melamine, epichlorohydrin/polyamine or epichlorohydrin/polyamine-polyamide; passing the treated tubing continuously along its longitudinal axis through a first heat-treating zone under conditions which permit shrinking and thus drying it, the effective temperature being in the range from about 70 to 90°C at the beginning of the first heat-treating zone and being in the range from about 100 to 130°C at the end of the first heat-treating zone; remoistening the dried tubing; and passing the tubing continuously through a second heat-treating zone and thus drying it, wherein the speed of advance of the tubing at the outlet of the second heat-treating zone is equal to or at most 2% greater than that at the inlet to the second heat-treating zone.
4. A process for the manufacture of a packag-ing material as claimed in Claim 3, wherein said treating step comprises treating both the outside and the inside surface of the tubing with said pre-con-densate-containing fluid.
5. A process for the manufacture of a packag-ing material as claimed in Claim 3, wherein said re-moistening step comprises treating the inside of the tube with a fluid containing said pre-condensate.
6. A process as claimed in Claim 3, wherein the speed of advance of the tubing at the outlet of the first heat-treating zone is from about 2 to 10%
lower than the speed of advance at the inlet to this zone.
lower than the speed of advance at the inlet to this zone.
7. A process as claimed in Claim 3, wherein said first heat-treating step comprises passing the tubing through the roll nip of a first pair of squeeze rollers having driven rollers each rotating at the same first peripheral speed, and after the water-insoluble coating of condensation product has been formed and the tubing has been dried, passing the tubing through the roll nip of a second pair of squeeze rollers, which is located at a distance from the first pair and has driven rollers each rotating at the same second peripheral speed, the first peripheral speed being about 2 to 10% greater than the second peripheral speed, and further comprising the step of filling the tubing with supporting gas while passing between the first and second pairs of squeeze rollers.
8. A process as claimed in Claim 7, wherein in the first heat-treating zone the tubing is sub-jected to the action of heat for a period in the range from about 1.5 to 3 minutes.
9. A process as claimed in Claim 3, wherein the temperature prevailing at the beginning of the second heat-treating zone is within the range from about 70 to 90°C and the temperature prevailing at the end of the second heat-treating zone is within the range from about 100 to 130°C.
10. A process as claimed in Claim 9, wherein the tubing is maintained in the second heat-treating zone for a period in the range from about 1.5 to 3 minutes.
11. A process for the manufacture of a packaging material as claimed in Claim 1, comprising the steps of:
treating the outside and the inside surface of a plasticizer-containing tubing which is comprised of cellulose hydrate gel and which has not yet been subjected to any preceding heat treatment, with a fluid containing a water-soluble pre-condensate comprising urea/formaldehyde, formaldehyde/melamine, epichlorohydrin/polyamine or epichlorohydrin/polyamine-polyamide; and subjecting the treated tubing to a single heat-treatment under conditions which permit shrinking of the part of the tubing, the temperature prevailing during heat-treatment being sufficient to form said water-insoluble, heat-cured synthetic condensation product from said pre-condensate and to dry the tubing.
treating the outside and the inside surface of a plasticizer-containing tubing which is comprised of cellulose hydrate gel and which has not yet been subjected to any preceding heat treatment, with a fluid containing a water-soluble pre-condensate comprising urea/formaldehyde, formaldehyde/melamine, epichlorohydrin/polyamine or epichlorohydrin/polyamine-polyamide; and subjecting the treated tubing to a single heat-treatment under conditions which permit shrinking of the part of the tubing, the temperature prevailing during heat-treatment being sufficient to form said water-insoluble, heat-cured synthetic condensation product from said pre-condensate and to dry the tubing.
12. A process as claimed in Claim 11, wherein the temperature at the beginning of said heat-treatment is in the range from about 90 to 110°C and the temperature prevailing at the end of said heat-treatment is in the range from about 140 to 160°C.
13. A process as claimed in Claim 11, wherein the tubing contains in its wall a chemical agent con-taining at least two N-methylol groups in the molecule for cross-linking the cellulose hydrate molecules, and wherein the tubing is subjected at the beginning of said heat-treatment to a temperature in the range of from about 70 to 90°C and at the end of said heat-treatment to a temperature in the range of from about 100 to 130°C.
14. A process as claimed in Claim 12 or 13, wherein the speed of advance of the tubing along its longitudinal axis at the outlet of said heat-treatment is from about 2 to 10% lower than that at the inlet to said heat-treatment.
15. A process as claimed in Claim 14, wherein said heat-treatment step comprises passing the tubing through the roll nip of a first pair of squeeze rollers having driven rollers each rotating at the same first peripheral speed, and then passing the tube through the roll nip of a second pair of squeeze rollers, which is located at a distance from the first pair provided and has driven rollers each rotating at the same second peripheral speed, the first peripheral speed being about 2 to 10% greater than the second peripheral speed, and further comprising the step of filling the tubing with a supporting gas in the space between the first pair of squeeze rollers and the second pair of squeeze rollers.
16. A process as claimed in Claim 15, wherein the tubing is subjected to said heat-treatment for a period in the range from about 3 to 8 minutes.
17. A sausage casing comprising the tubular packaging material defined by Claim 1.
18. A sausage casing as claimed in Claim 17, further comprising a sausage filling contained inside of said casing.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19803030035 DE3030035A1 (en) | 1980-08-08 | 1980-08-08 | TUBULAR PACKING SLEEVE, CELLULOSEHYDRATE WITH LOW SOURCE VALUE, WHICH CONTAINS THE TUBE WALL, THERMALLY HARDENED, WATER-INSOLUBLE SYNTHETIC CHEMICAL CONDENSATION PRODUCT, AS ARTISTICALLY THESE SAUSAGE |
| DEP3030035.7-23 | 1980-08-08 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1170898A true CA1170898A (en) | 1984-07-17 |
Family
ID=6109175
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000382885A Expired CA1170898A (en) | 1980-08-08 | 1981-07-30 | Tubular packaging material and method for its manufacture |
Country Status (8)
| Country | Link |
|---|---|
| US (1) | US4356199A (en) |
| EP (1) | EP0047391B2 (en) |
| JP (1) | JPS5758847A (en) |
| AT (1) | ATE7352T1 (en) |
| BR (1) | BR8105107A (en) |
| CA (1) | CA1170898A (en) |
| DE (2) | DE3030035A1 (en) |
| FI (1) | FI67652C (en) |
Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3013320A1 (en) * | 1980-04-05 | 1981-10-15 | Hoechst Ag, 6000 Frankfurt | FOR FOODSTUFFS, IN PARTICULAR SAUSAGE PRODUCTS, TUBULAR SLEEVE SUITABLE WITH A STITCHED SEAM AND METHOD FOR THEIR PRODUCTION |
| DE3040279A1 (en) * | 1980-10-25 | 1982-06-16 | Hoechst Ag, 6000 Frankfurt | FOR FOODS, ESPECIALLY SAUSAGE PRODUCTS, TUBULAR SLEEVE SUITABLE WITH A STITCH SEAM, METHOD FOR THEIR PRODUCTION AND THEIR USE FOR THE PRODUCTION OF CURVED OR RING SHAPED SAUSAGES |
| DE3045086A1 (en) * | 1980-11-29 | 1982-06-24 | Hoechst Ag, 6000 Frankfurt | HOSE COVER, ESPECIALLY SAUSAGE SLEEVE, WITH STEAM-PROTECTIVE LAYER, METHOD FOR THEIR PRODUCTION AND THEIR USE |
| DE3105718A1 (en) * | 1981-02-17 | 1982-09-02 | Hoechst Ag, 6000 Frankfurt | FOR FOODSTUFFS, ESPECIALLY SAUSAGE PRODUCTS, SUITABLE SMOKE-PERMITTING TUBULAR SLEEVE WITH A STITCHED STITCH AND METHOD FOR THE PRODUCTION THEREOF |
| DE3108795A1 (en) * | 1981-03-07 | 1982-09-16 | Hoechst Ag, 6000 Frankfurt | FOR FOODSTUFFS, ESPECIALLY SAUSAGE PRODUCTS, SUITABLE FIBER-REINFORCED HOSE COVER AND METHOD FOR THEIR PRODUCTION |
| DE3139481A1 (en) * | 1981-10-03 | 1983-05-05 | Hoechst Ag, 6230 Frankfurt | SMOKED SLEEVES SUITABLE FOR SMOKING FOODS, ESPECIALLY FOR SMOKED SAUSAGE PRODUCTS, PROCESS FOR THEIR PRODUCTION AND THEIR USE |
| DE3328947A1 (en) * | 1983-08-11 | 1985-02-28 | Hoechst Ag, 6230 Frankfurt | MOLD-RESISTANT SHELL MATERIAL |
| DE3617500A1 (en) * | 1986-05-24 | 1987-11-26 | Hoechst Ag | SAUSAGE CASE WITH IMPROVED CALIBER CONSTANCE |
| US4967798A (en) * | 1987-04-24 | 1990-11-06 | Hoechst Aktiengesellschaft | Packaging casing based on cellulose having improved processing characteristics |
| CA2047477C (en) * | 1990-08-08 | 1998-04-21 | Xavier Jose Quinones | Colored cellulosic casing with clear corridor |
| CA2110096C (en) * | 1993-07-23 | 1999-11-02 | Eric M. J. Verschueren | Fibrous food casings having modified release properties and methods of manufacture |
| US6032701A (en) * | 1998-01-29 | 2000-03-07 | Teepak Investments, Inc. | High moisture alkali smoke food casing |
Family Cites Families (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE483424A (en) * | 1942-07-31 | |||
| US2616874A (en) * | 1951-07-19 | 1952-11-04 | Rohm & Haas | Methylol derivatives of ureido-polyamines |
| US2796362A (en) * | 1955-06-29 | 1957-06-18 | American Cyanamid Co | Surface treatment |
| DE1024322B (en) * | 1956-05-19 | 1958-02-13 | Kalle & Co Ag | Process for the continuous production of edible artificial guts |
| US2926154A (en) * | 1957-09-05 | 1960-02-23 | Hercules Powder Co Ltd | Cationic thermosetting polyamide-epichlorohydrin resins and process of making same |
| US2999757A (en) * | 1959-10-30 | 1961-09-12 | Union Carbide Corp | Method for producing cellulosic sausage casings and product |
| US3378379A (en) * | 1963-05-21 | 1968-04-16 | Union Carbide Corp | Food casing and method of producing same |
| DE1704151A1 (en) * | 1967-09-27 | 1971-04-22 | Kalle Ag | Process for the production of sausage casing material from thermoplastic material which can be converted into wreath daemies |
| DE2128613A1 (en) * | 1971-06-09 | 1972-12-28 | Faller, Willi, 6000 Frankfurt | Sausage casing - consisting of spun fleece of synthetic fibre material |
| DE2246829C3 (en) * | 1972-09-23 | 1980-07-31 | Hoechst Ag, 6000 Frankfurt | Process for the production of molded articles from cellulose hydrate |
| US3935320A (en) * | 1973-04-04 | 1976-01-27 | Union Carbide Corporation | Tubular cellulosic casing with cationic thermosetting resin coating |
| DE2654417A1 (en) * | 1976-12-01 | 1978-06-08 | Hoechst Ag | MOLDED BODIES, IN PARTICULAR PACKAGING MATERIAL, BASED ON CHEMICALLY MODIFIED CELLULOSE HYDRATE AND A METHOD FOR MANUFACTURING THE MOLDED BODY |
| DE2822886A1 (en) * | 1978-05-26 | 1979-11-29 | Hoechst Ag | TUBE-SHAPED PACKAGING SHELL BASED ON CELLULOSE HYDRATE WITH FIBER INSERT IN THE SHELL WALL AND OPTICALLY EFFECTIVE CHEMICAL COMPOUND ON THE SURFACE AS WELL AS THE PROCESS FOR THEIR PRODUCTION |
| DE2832926A1 (en) * | 1978-07-27 | 1980-02-07 | Hoechst Ag | CELLULOSE HYDRATE HOSE WITH AN AGING-RESISTANT BARRIER LAYER FROM SYNTHETIC COPOLYMERISAT ON THE OUTSIDE AND METHOD FOR THE PRODUCTION THEREOF |
-
1980
- 1980-08-08 DE DE19803030035 patent/DE3030035A1/en not_active Ceased
-
1981
- 1981-07-29 AT AT81105975T patent/ATE7352T1/en not_active IP Right Cessation
- 1981-07-29 EP EP81105975A patent/EP0047391B2/en not_active Expired
- 1981-07-29 DE DE8181105975T patent/DE3163498D1/en not_active Expired
- 1981-07-30 CA CA000382885A patent/CA1170898A/en not_active Expired
- 1981-08-04 US US06/290,059 patent/US4356199A/en not_active Expired - Fee Related
- 1981-08-06 FI FI812435A patent/FI67652C/en not_active IP Right Cessation
- 1981-08-07 BR BR8105107A patent/BR8105107A/en not_active IP Right Cessation
- 1981-08-07 JP JP56123187A patent/JPS5758847A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| US4356199A (en) | 1982-10-26 |
| BR8105107A (en) | 1982-04-27 |
| FI67652B (en) | 1985-01-31 |
| EP0047391B1 (en) | 1984-05-09 |
| ATE7352T1 (en) | 1984-05-15 |
| FI812435L (en) | 1982-02-09 |
| JPS5758847A (en) | 1982-04-08 |
| FI67652C (en) | 1985-05-10 |
| DE3163498D1 (en) | 1984-06-14 |
| EP0047391A1 (en) | 1982-03-17 |
| DE3030035A1 (en) | 1982-03-11 |
| EP0047391B2 (en) | 1989-06-21 |
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