US 3634947 A
An apparatus for conditioning fibrous materials includes a rotatable drum in which the fibrous material may be tumbled, as in an automatic laundry dryer, and held, to the interior wall of the drum, so as to be in form-retaining relationship therewith, a base which has on an exterior surface thereof a conditioning agent for the fibrous materials. On contact with the tumbling fibrous materials, the conditioning agent is removed from the base and is deposited on the materials in sufficient quantity to condition them. Usually, the conditioning agent is a fabric softener and/or antistatic agent of the synthetic organic surface active type, the base is a thin flexible sheet or strip of material, such as paper or suitable plastic, the conditioning takes place in an automatic laundry dryer and the base is held to the dryer interior wall by an adhesive, such as a pressure sensitive adhesive.
Claims available in
Description (OCR text may contain errors)
United States Patent Furgal 1 Jan. 18,1972
 COATING APPARATUS  Inventor: Henry P. Furgal, Bernardsville, NJ.
 Assignee: Colgate-Palmolive Company, New York,
 Filed: Oct. 20, 1970  Appl.No.: 82,314
Primary Examiner-Morris Kaplan AttorneyHerbert S. Sylvester, Murray M. Grill, Norman Blumenkopf, Ronald 8. Cornell and Robert L. Stone  ABSTRACT An apparatus for conditioning fibrous materials includes a rotatable drum in which the fibrous material may be tumbled, as in an automatic laundry dryer, and held, to the interior wall of the drum, so as to be in form-retaining relationship therewith, a base which has on an exterior surface thereof a conditioning agent for the fibrous materials. On contact with the tumbling fibrous materials, the conditioning agent is removed from the base and is deposited on the materials in sufficient quantity to condition them. Usually, the conditioning agent is a fabric softener and/or antistatic agent of the synthetic organic surface active type, the base is a thin flexible sheet or strip of material, such as paper or suitable plastic, the conditioning takes place in an automatic laundry dryer and the base is held to the dryer interior wall by an adhesive, such as a pressure sensitive adhesive.
5 Claims, 5 Drawing Figures PATENIEDmnamz 35343 39 33 224?? xii INVENTOR. HENR P. FURGAL SUBJECT OF THE INVENTION This invention relates to the conditioning of fibrous materials by contacting them with a base having a conditioning agent on a surface thereof. More particularly, the contacting is effected in a rotatable drum, such as that of an automatic laundry dryer, and the base is held to an interior wall of the drum so that, even if it is normally flexible, it is maintained in form'retaining relationship with the drum. The invention includes a conditioning article which comprises the flexible base, conditioning agent on the base and means for holding the flexible base in form-retaining relationship with an interior wall of a tumbling drum, which means is preferably a pressure sensitive adhesive.
BACKGROUND OF THE INVENTION In the past conditioning agents have been used to improve the properties of fibrous materials. Among the more important properties that have been changed by such agents are softness, electrostatic capacity and wrinkling characteristics. Although most treatments conducted in the household laundry to modify these properties have been effected in the washing machine, usually by addition of a conditioning agent to the last rinse, such methods possess certain inherent disadvantages which have led to attempts to treat laundry and fibrous materials to be conditioned in other operations which would normally be utilized in the laundry process. By effecting such treatments in the dryer, the necessity for the conditioning agent to be substantive to the fabrics and to adhere to them strongly in preference to the solvent of the dilute solutions of the rinse water would be obviated. Thus, soluble treating compositions would be employable if there was a way to distribute them over the surfaces of the fibrous materials being treated when such surfaces were not immersed in wash water or rinse water.
The use of sprays of fabric softeners or other applications of such liquids to the laundry in the dryer usually requires complicated and relatively expensive installations and even with these, staining, spotting or other detrimental effects due to local applications of excess conditioning agent may be observed. If a flexible paper, sponge or cloth sheet is impregnated with conditioning agent, such as quaternary ammonium salt, and the product is tumbled with laundry in the dryer, staining is sometimes noted, apparently due to temporary entrapments of the flexible conditioning article in laundry being treated, which cause the application of more condition ing agent than is desirable at particular locations on the treated materials. Such local over applications may also be caused by cracking and flaking off of the conditioning compositions when the flexible substrate is folded, creased, twisted, bent or otherwise distorted during tumbling with laundry, due to the conditioning material being strained by such actions. Of course, if the cationic conditioning agents used, such as the quaternary ammonium salts, contact materials containing color bodies or heavy metal ions, such as ferric or ferrous ions, very obvious and substantive stains may be produced which are extremely difficult to remove from the fabrics. They often require dry cleaning and this is not always completely successful. Even if such actions do not take place regularly, the possibility of only occasional adverse effects of this type can sometimes prevent the satisfactory marketing and sales ofsuch a product.
In the past it has been suggested that an improved method of applying conditioning agent to fibrous materials in the dryer would involve the use of form-retaining bases for such material so that the base would not bend, fold, crease or flex sufficiently to cause enough strain to make the coating of condi tioning composition flake off from it. Thus, solids such as polystyrene foam balls have been taught to be useful when coated with fabric conditioner. Such articles tumble with the laundry and, although they are not difficult to locate after use, they have to be found and separated from the laundry after completion of the treatment cycle. Furthermore, they should be of a certain density to prevent them from riding atop the laundry load and not participating sufficiently in the tumbling contact. Finally, although entrapment in the laundry and resulting staining of the materials being treated rarely occurs with such articles, it is possible in some cases, especially if the items being laundered are large in size and can become folded about the conditioning article.
DESCRIPTION OF THE INVENTION Disadvantages accompanying other methods of conditioning laundry in the drying operation are obviated in large part by the present invention. Thus, the apparatuses, for conditioning fibrous materials in accordance with this invention allow the conditioning of-laundry in the dryer, permit the use of water soluble nonsubstantive conditioning agents, do not result in cracking and flaking off of conditioning composition coatings due to entrapment of the conditioning article in the laundry and allow it to be found readily, after completion of the conditioning treatment. The method allows the use of flexible bases for the conditioning compositions and facilitates their storage, application and removal. It allows economical production and convenient packaging and use of the conditioning articles.
In accordance with the present invention, an apparatus for conditioning fibrous materials comprises an automatic laundry dryer drum or similar container for them, means for rotating the drum and tumbling fibrous materials contained therein, and held to an interior wall of the drum in formretaining relationship therewith, a base, having on an exterior surface thereof a conditioning agent for the fibrous material. The conditioning agent, preferably a fabric softener or antistatic agent, is removable from the base on contact with the tumbling materials and is deposited on the materials in sufficient quantity to condition them. In preferred forms of the invention, the base is a thin flexible sheet or strip of material, such as paper or suitable plastic, the conditioning agent is waxy in nature and is mostly external to the base, and the means for holding the base to the interior of the dryer or other container is an adhesive, preferably a pressure sensitive adhesive, which makes the article readily applicable and removable from the drum wall. Also within the invention are the fabric conditioning articles, in strips or sheets, or rolled, and combinations of dispensers with such articles. Of course, uses of such apparatus and articles are also part of the invention.
Various details, constructions, operations, uses and advantages of the invention will be apparent from the following description, taken in conjunction with the illustrative drawing of some embodiments thereof, in which drawing:
THE DRAWING FIG. 1 is a vertical sectional view of the interior of an automatic laundry dryer drum;
FIG. 2 is a vertical section of a fiber conditioning tape of the present invention;
FIG. 3 is a vertical section of another such tape;
FIG. 4 is a side elevation of a roll of conditioning tape, wound around a mandrel tube; and
FIG. 5 is a vertical section of a combination dispenser and cutter for a roll of conditioning tape, showing the tape in position therein.
DETAILED DESCRIPTION OF THE INVENTION In the apparatus of FIG. 1, automatic laundry dryer drum 11 has an inner wall 13 on which baffles 15 are fastened, molded or pressed out. Interior wall 13 is form-retaining and usually is of steel, as are the baffles 15, the function of which is to assist in tumbling laundry 17 being dried in the automatic laundry dryer. As the dryer drum 11 rotates in a clockwise direction, as indicated by arrow 19, the baffles tend to lift the laundry upward and to the left, after which it is dropped down shortly before reaching the top of the dryer, usually at a point corresponding to about 330. Drum 11 has operatively connected to it pulley 21 which is turned by belt 23, rotated by connection with driving motor 25. Shown fastened to the interior wall 13 is a form-retaining article 27 having a base portion 29 and a coating 31 of conditioning agent on an external surface thereof, from which it can be abraded off onto the surfaces of tumbling laundry articles, such as those designated at 17, during contact made under the conditions in the dryer. Also, shown are creped paper tapes 33 and 35, which have fabric softening and antistatic agents on an external surface thereof and are held to leading surfaces of baffles by pressure sensitive adhesive or other suitable means. Of course, in an automatic laundry dryer, means are provided for the flow of warm air through the dryer and the venting of humid air from it. Such means are conventional and are not specifically illustrated herein. Also, it will be noted that the tapes 33 and 35 will usually extend substantially across the entire lengths of the baffles and the dryer drum interior.
In FIG. 2 are shown details of construction of the conditioning agentcoated creped tape 33. The creped paper base 37 has a coating of fabric softener 39 applied to the top surface thereof and on the bottom, a coating of pressure sensitive rubber-type adhesive 41. As is illustrated in FIG. 1, a length of such tape is installed coaxially with the drum 1] on baffle 15 by pressing the pressure sensitive adhesive against the surface of the baffle. For best contact with the laundry the installation is on the leading edge of the baffle, as shown but in other cases, installation can be on the trailing edge, when such a good contact is not required or desirable. In FIG. 3 is shown a similar tape 43 having a base section 45, conditioning composition 47, adhesive 49 and a thin waxy coating 51, to prevent adhesive 49 from adhering to conditioning agent 47. As illustrated, the coating is on the conditioning agent but it may be utilized as a separating thin sheet of waxy paper or similar material to permit easy release.
In FIG. 4, cylindrical cardboard or paperboard mandrel 53 has wrapped about it a length of conditioning tape 43, making a roll 54 from which the tape is conveniently dispensed, ready for use. In FIG. 5, a dispenser frame or support 57 holds shaft or mounting means 55 onto which mandrel 53 is operatively mounted. A roll 54 of tape 43, wound on said mandrel, is unwound therefrom and led over a cutting edge 59, where it can be severed to desired lengths for application to the interior of the dryer drum.
The apparatus for conditioning fibrous materials is one which has an enclosure which is either movable itself or in which clothing or fabric fibers to be treated can be moved about, so as to be brought into repeated contact with a conditioning agent. A preferred apparatus includes a rotatable automatic laundry dryer drum so that the conditioning can be ef fected by the housewife during the ordinary drying of laundry. Nevertheless, industrial installations and apparatuses different from but functionally equivalent to the dryer drum may also be employed. Normally, these will rotate, although other means of agitation and movement are also applicable. Such containers will usually be form-retaining but may be made of somewhat flexible material, providing that form-retaining bases for the conditioning material are attached to them or, if flexible bases are used, that there are sections of the container or drum wall which are form-retaining, to which such bases may be attached. It is preferable that the dryer drum be one which rotates and means will be provided for efiecting such rotation, said means usually being a dryer motor-belt-pulley combination. Also, when drying with conditioning, means will be provided for circulating drying air at an elevated temperature through the articles being treated in the drum.
An important aspect of the present invention is in the fixing in position with respect to a drum wall of the conditioning means being employed. Thus, if the conditioning means used is a coated fonn-retaining article, such as a polystyrene foam slab, represented at 27 in FIG. 1, rather than to allow it to be tumbled with the clothing one will fasten it to a portion of the drum wall or baffle thereon. Thus, there will be a predictable number of revolutions of the conditioning article into contact with tumbling clothing and entrapment of it will be prevented. Furthermore, whatever the density of the base, the contact with the clothing will be independent thereof. Also, after conclusion of the conditioning, the housewife will know exactly where to find the conditioning article. By repeated use, she will be able to determine the best location of the article for effecting the most desired conditioning treatments.
If the conditioning article is form-retaining, it may be any of various suitable materials of construction, including paperboard, cardboard, corrugated paperboard, other cellulosic products, wood, metal, mineral, vegetable, and synthetic organic polymeric plastics, either in foam, solid or hollow form or of reinforced or similar structures. Thus, polyvinyl chloride, polystyrene, foamed polystyrene, either open or closed cell, rigid polyurethane foam, glass reinforced polyester, balsawood, soft pine, coconut shells, foamed concrete, smooth pumice or other equivalent bases may be employed. These may be perforated or continuous at their surfaces and may be of various forms, such as tubes, e.g., cylinders or rounded tubular shapes, discs, parallelograms, such as rectangles, parallelepipeds, such as cubes, ellipsoids, spheres and many other shapes, and may also be symbolic or decorative, e.g., pictures, figures, flowers, symbols.
As was previously mentioned, it is preferred to employ flexible substrates for the conditioning composition and these will usually be in sheets, films or strips of any of a wide variety of suitable materials including papers, plastics, rubbers, metals, cloths, sponges, screens, fibers, felts and nonwoven fabrics. The various fibrous materials may be natural or synthetic and usually, preferably will be cellulosic. However, they may also be of resilient foamed plastics, such as the polyurethanes. While the thickness of the form-retaining bases may be almost any desired, usually being at least 0.] cm. thick and, rarely being of more than 10 cm. thick, that of the thin flexible material, such as sheeting, will usually be from 0.001 to 0.1 cm. but in some cases, as when flexible foams or sponges are employed, the thickness may be increased to as much as about 1 cm. without detrimental effects. The main consideration is that the material should be sufficiently flexible to confonn to and fit tightly against the form-retaining inner wall of the dryer drum. Of course, the desired flexibility and thinness will also assist in making the conditioning agent easily rolled into a convenient package, which may be incorporated in a dispenser. Although it is most useful to have the thin flexible conditioning article in roll form, it may also be used as a flat strip or sheet without being packaged into a roll or a roll dispenser.
Among the fabric softeners and antistatic agents that are usable in accord with the present invention are the nonionic surface active materials, including higher fatty acid monolower alkanolamides, higher fatty acid dilower alkanolamides, block copolymers of ethylene oxide and propylene oxide, having hydrophilic and lipophilic groups, alkyl (preferably middle alkyl) phenol polylower alkylene oxide lower alkanols, polymers of lower alkylene glycols, polyalkylene glycol ethers of higher fatty alcohols and polyalkylene glycol esters of higher fatty acids. Among the anionic agents are the higher fatty acid soaps of water soluble bases, higher fatty alcohol sulfates, higher fatty acid monoglyceride sulfates, sarcosides, taurides, isethionates and linear higher alkyl aryl sulfonates. Cationic compounds include the higher alkyl dilower alkyl amines, dihigher alkyl lower alkyl amines and quaternary compounds, especially quaternary ammonium salts, e.g., quaternary ammonium halides. In the preceding description, lower, as applied to various hydrocarbyl-containing groups, indicates a carbon content of from i to 6, preferably from 2 to 3. Similarly, higher includes compounds having from 10 to 20 carbon atoms, preferably from 12 to 18. Of course, since it is important to the present invention that the conditioning composition be in a solid form, so that it can have conditioning agent gradually removed from it by contact with tumbling laundry fabrics in a dryer or similar machine, the fabric softening and/or antistatic agents will be chosen to be in the solid state. Mixtures of nonionic conditioning agents with either cationics or anionics of the types mentioned above may also be used and generally, the proportions of components of such mixtures will be chosen so as to have the final product in most desired waxy condition and satisfactorily removable by a combination of moisture, heat and abrading contact with laundry that exists in an automatic dryer.
Specific examples of surface active materials of the types described above are given in the text Synthetic Detergents by Schwartz, Perry and Berch, published in I958 by Interscience Publishers, New York. See pages to I43. Among the more preferred of these are:
Nonionic-nonylphenoxy polyethoxy ethanol; stearic monoethanolamide; stearic diethanolamide; block copolymers of ethylene oxide and propylene oxide (Pluronics);
Anionic-sodium soap of mixed coconut oil and tallow fatty acids; sodium stearate; potassium stearate; sodium laurate; tallow alcohols sulfate;
Cationic-dilauryl dimethyl quaternary ammonium chloride; hydrogenated tallow alkyl trimethyl ammonium bromide and benzethonium chloride.
The above list is only illustrative of some of the compounds useful in accordance with the present invention. Conditioning agents of these types are well known in the art and others than those mentioned above may also be used satisfactorily.
In addition to the fabric softening and/or antistatic and antiwrinkling agents which are the principal conditioning compounds, other components may also be present in these conditioning compositions for their adjuvant effects. Thus, other conditioning agents may be used, including those designed to treat the fabrics in other ways than in softening. For example, perfumes, brighteners, bactericides, solvents, thickening or hardening agents, stabilizers and other materials may be incorporated in the conditioning compositions. In some cases, small quantities of water may be present, especially when the components form hydrates. Plasticizers and release agents may be employed to assist in having the conditioning compounds satisfactorily coat the substrate and to facilitate release of the conditioning agent from the treated articles upon subsequent laundering. Solvents and dispersants may be used to assist in applying the conditioning compositions to the base, principally in those cases where a flexible material, such as paper, is being coated with the conditioning composition. The types and proportions of the various adjuvants used will be chosen so to make them interfere with the operations of the conditioning compounds.
The final conditioning composition is preferably waxy in appearance and is capable of being stored at room temperature without melting, while yet being satisfactorily picked up by fabrics in the operation of an automatic laundry dryer, when the fabrics tumbled into contact with the conditioning composition. The conditioning composition will be form-retaining at temperatures below C. and preferably, also at all temperatures below 40 C. It may tend to fuse or melt under the higher temperatures obtaining in the dryer, such as 70 to 90 C. but usually will be only sufficiently softened, even in the presence of the plasticizers, to be abraded off a treating article onto the surface of material to be conditioned, at dryer conditions, including the presence of moisture and drying gas at an elevated temperature. The conditioning composition should be removable from a substrate rather smoothly and in sufficient quantity to condition fabrics, at a temperature from 40 to 90 0, preferably from 50 to 80 C. Normally, to effect these purposes, the fabric softener and/or antistatic agent, the surface active conditioning agent mentioned previously, will be a major proportion of the conditioning composition, usually from 51 to I00 percent thereof. Preferably it will comprise from 75 to I00 percent of the composition. The various adjuvants will normally constitute any remainder of the composition.
When the conditioning composition is employed as a coating on the substrate, the thickness of the coating applied will normally be within the range of 0.0005 to 0.5 centimeter, generally from 0.001 to 0.3 cm. and preferably from 0.005 or 0.05 to 0.2 cm. The thickness given is that external to the outer surface of the thin flexible material coated. A somewhat porous or rough surfaced substrate or one having indentations will normally be preferred so that the coating composition may penetrate below the outer surface to a sufficient depth to hold the external coating firmly to the surface and prevent its cracking or flaking off from the surface during use. As a example of such a substrate may be mentioned paper toweling, having a creped, crinkled or roughened appearance, as contrasted to a smooth sheet of paper. Also, flexible polyurethane foam can be used. A minor proportion of the external thickness of coating agent may be below the surface. This will usually be held to 10 to 30 percent of that external to the base. In terms of weights applied, the conditioning compositions will normally be employed in the range of 0.0005 to 0.5 g./sq. cm., preferably from 0.001 to 0.3 g./sq. cm. and most preferably from 0.005 to 0.2 g./sq. cm.
The preparation of the conditioning composition is easy, usually requiring only the melting together of various components. They may be applied to one side of the flexible or form-retaining base by any suitable method, preferably by roll, doctor blade or spray application and similarly, if an adhesive is to be employed, it may be applied to a suitable portion of the base, usually the opposite major face, in a similar manner. Such methods are detailed in an application for patent entitled PROCESS FOR THE MANUFACTURE OF FABRIC CON- DITIONING ARTICLE, filed by P. J. Falivene, on the same day as this application and another application entitled FIBER CONDITIONING ARTICLE, filed by P. S. Grand, et al., also on the same day as this application.
After coating of the base with conditioning material, this may be overcoated with a layer, usually less than 0.0] cm. thick, of wax, such as petroleum wax; which will be readily removed therefrom in the dryer and which will aid in preventing adhesion of the conditioning composition to other materials during storage, such as fastening to pressure sensitive adhesive with which it is brought into contact. Of course, instead of the waxy coating, waxed paper, treated release paper, creped papers, or a plastic, such as polyethylene film or other suitable material may be used as an overlay to prevent such adhesion.
The means for holding the coated base to the interior of the dryer or wall of the container in which fibrous materials are treated may be any suitable fastener. When using rigid or form-retaining bases, holding may be by spring loaded clamp, screws, press fitting, adhesion, partial fusion, taping, typing, or insertion into a prepared cavity or other enclosure. The place of fastening may be on any suitable portion of the dryer drum interior, including the baffles and other locations on the longitudinal surface thereof.
For the use of flexible bases or substances, it is generally important that they be fastened to a form-retaining element, usually the interior of the dryer wall or a baffle thereon. This is so because in the most desirable uses of the present articles they will be maintained in position so that they cannot flex unduly and thereby, flaking off of coating composition will be inhibited. In some embodiments of the invention, wherein the conditioning agents brittleness" represents no problem, some of the advantages of the invention can be obtained by fastening such a flexible conditioning article to the dryer interior wall so that it is held in place thereon at a point or area but is still capable of flexing. However, it is highly preferred to maintain the conditioning article in a form-retaining state during the treatment of fibrous materials.
The various means mentioned above with respect to holding other bases to the dryer wall may also be used to hold flexible conditioning articles. The most preferred means for effecting such holding is an adhesive and of this type, the best is a pressure sensitive adhesive. Such adhesive materials are well known, usually being based on rubber or synthetic organic polymeric plastic latexes and containing ingredients which keep them tacky, so that they may be readily applied, with pressure, to a surface and are subsequently removable therefrom. It has been found that various of such pressure sensitive adhesives. such as are employed in adhering masking tapes and bandages or adhesive tapes are useful, even at the elongated temperatures that are encountered in the automatic laundry dryer. In the event that any section of such adhesives is desirable, those will be employed which maintain their adhesive activity and tackiness or plasticity at the elevated temperature of dryer operations. Also, those adhesives that are readily removed and leave no deposits behind after removal will be highly preferred, since it is desired to maintain the smooth and clean surface of the dryer interior to avoid staining clothing Again, many of the commercially available pressure sensitive adhesives are satisfactory in this respect. Applications of such adhesive to the paper or other flexible strips or tapes may be with machinery and usually is effected after conventional coating of another face of the base with conditioning composition. The adhesive will usually be on an entire surface for best holding power but can be spot or strip printed onto the base.
Although the form-retaining materials normally are fastened to the surfaces of the dryer drum intermediate the baffles it is often preferred to mount the flexible tape conditioning articles on the baffles or other raised portions of the interior of the dryer drum. Generally, this will be on a leading edge so as to promote best contact with the materials being conditioned. However, other locations are also useful. When a relatively long and narrow conditioning article, such as a tape, is employed, it will generally be applied longitudinally or coaxially with the drum. Yet, in some applications it may be applied circumferentially or partially circumferentially.
After preparation of the conditioning article, it is wrapped or otherwise packaged for shipment, storage and subsequent use. WHen pressure sensitive adhesives are employed, care will be taken to cover the adhesive so that its tackiness is maintained. When strips, sheets or tapes are used, a good way to protect the adhesive is to pack the conditioning articles in such a way that the adhesive contacts either a waxy surface of conditioning composition, wax coating thereon or waxed paper or other intermediate protecting film, which thereby acts to protect both the coated composition and the adhesive. A convenient way to do this is to roll a strip of such pressure sensitive adhesive containing conditioning article about a mandrel or tube, to form a cylinder, such as is illustrated in FIG. 4. If desired, such cylinder may be mounted on a dispenser or other base and the conditioning tape may be dispensed in the same manner as is employed for dispensing other tapes, such as transparent sealing tapes and masking tapes.
The present articles are simple to employ and the treating methods are effective for conditioning fabrics without special care being necessary on the part of the user. The conditioning particle is positioned in the automatic dryer or tumbling device immediately before a drying or treating operation commences. The location selected may be on the drum or a baffle, as previously mentioned or in such a location on the drum as experience has indicated will provide the best softening or antistatic treatment with the conditioning agent being employed. Then, the dryer is started with a load of damp laundry or other materials to be treated and the laundry and conditioning article are in relative movement, with a combination of heat, moisture and abrading action due to contact causing the release of conditioning agent from article and deposit on the fabrics. Although it is preferred to use an automatic laundry dryer, equivalent machines may be employed and in some instances, heat and drying air may be omitted for part or all of the cycle, although generally, air will be employed and will be circulated frequently. Normally there will be about to 50 changes ofdrying gas in the dryer drum per minute and the gas temperature will be from l0 to 90 C., preferably from 50 to 80 C. The dryer will usually revolve at about to I00 revolutions per minute, preferably 40 to 80 rpm. The weight of laundry employed will usually be from 4 to l2 pounds,
preferably from 5 to 10 pounds, dry weight. This will fill II) to percent of the volume of the dryer, preferably about 30 to 60 percent thereof. Drying will usually take from 5 minutes to 2 hours and generally from 20 minutes to 1 hour will be sufficient, with synthetic fabrics, such as nylon, polyesters and synthetic-natural blends requiring shorter periods of time than cotton laundry. The synthetics may often be dried satisfactorily in from 3 to 10 minutes and resin-treated fabrics of the permanently pressed or nonwrinkling types may be dried in from 10 minutes to one-half hour.
After completion of the conditioning operation and the drying of the laundry, the conditioning article is examined. lf sufflcient softener remains, the article may be left in place and employed again until complete removal of the coating of conditioning agent. If the laundry is not satisfactorily conditioned, additional tumbling thereof may be in order. To obtain different levels of conditioning activities or different effects, there may be employed several treating articles or a plurality of different treating articles, located at various places inside the drum. Of course, after the coating is consumed, a formretaining base may be covered with a new application of conditioning agent and a flexible base, such as a tape may be removed and discarded.
Other details about the use of the present and related compositions, articles and methods may be found in an application for patent entitled FABRIC CONDITIONING METHODS, ARTICLES AND COMPOSITIONS, filed by G. T. Hewitt, et al., on the same day as the present application, as well as in the other patent applications, previously mentioned.
The advantages of the present invention have been indicated but will be recited briefly here. In summary, it is considered to be important that the conditioning article is readily locatable in the dryer at a particular place and that the degree of contact between it and the tumbling laundry is regulated to a significant extent by having the article fastened to the dryer interior. Thus, the article is easy to position and is readily found and removed upon the completion of the conditioning. The degree of conditioning is controllable by varying the position and number or size of the articles on the drum. By utilizing form-retaining articles or by making them form-retaining by fastening to such a wall or base, problems of flaking off or cracking of the conditioning agent are minimized. The various conditioning articles are readily made by commercially economic processes and, especially with respect to the tapes, are capable of being continuously mass produced and readily stored, shipped and dispensed. Although intended primarily for softening, decreasing electrostatic activity and decreasing wrinkling of natural and synthetic fabrics, the present articles may also be used for effecting other treatments of fibers and fabrics, by having applied active conditioning agents such as bactericides, fungicides, silicones, sizes, etc., in other suitable bases, such as waxes, hydrophilic solids, fats, carriers or other such depositable media.
The following examples illustrate various embodiments of the invention. Unless otherwise indicated, all parts are by weight, temperatures are in degrees Centigrade and the measurements are in the metric system. The examples are not intended to limit the scope of the invention because it is evident that various modifications may be made and equivalents may be substituted without departing from the spirit thereof.
EXAMPLE I A melt is prepared by heating 70 parts of stearic monoethanolamide and 30 parts of stearic diethanolamine to a temperature of about C., while mixing to maintain uniformity of the composition. The melt is then applied to a sheet of toweling paper, which is creped, and has a thickness of approximately 0.1 cm. Application is by means of a roller, dipping into a bath of melt and depositing a uniform layer of coating composition onto one side of the toweling. The toweling is approximately I meter wide and the deposit of conditioning agent is to a depth of about 0.05 cm. above the surface and penetration is to a depth of about 0.015 cm. below the surface. The penetration is kept low by the rapid cooling of the melt immediately after coating, which cooling is effected by an air flow directed onto the coated paper after withdrawal from contact with the coating roller. Subsequently, a similar coating of commercial rubber latex adhesive of the pressure sensitive type is applied to the opposite side of the paper, to a depth of about 0.02 cm., with penetration being about 0.005 cm. The adhesive may be applied as an emulsion or from a solvent, in either of which cases solvent or dispersing medium is evaporated therefrom immediately after application. In those cases where the adhesive requires heating to effect a cure or when heat is utilized to evaporate solvent, to prevent melting off of the conditioning agent, the adhesive may be applied first. The width of paper is cut with a knife and the cut, treated adhesive paper is wound on individual spools, each approximately cm. wide, with the lengths of conditioning tape on the spools being about l0 meters. The spools are paperboard tubes of approximately 8 cm. outside diameter and are about 0.4 cm. thick. If used in 20 cm. lengths, each spool contains enough conditioning tape for 50 applications.
In this preferred embodiment of the invention, the spool of conditioning tape, containing conditioning composition on one surface and pressure sensitive adhesive on the other, is mounted on a dispenser-holder of the type illustrated in FIG. 5. This is approximately boxed and is ready for shipment, sale and use.
In use, a 20 cm. length of the paper tape is removed from the roll and is cut by a knife or a serrate edge of the dispenser. It is then applied to the leading edge of an internal baffle of the automatic dryer drum in a direction coaxial with the drum. The drum is then rotated so that the paper is at the top thereof and laundry to be conditioned is added, after which normal drying cycle is commenced. The laundry treated is a mixture of wearing apparel and household articles, totaling eight pounds, including cotton, synthetic fibers, especially polyesters, polyacetates and blends of these plastics other or with cotton, nylons, rayons and resin-treated, permanently pressed and wrinkle resistant fabrics. The wash comprises approximately 50 percent of cotton articles, 20 percent polyester-cotton blends, 10 percent permanently pressed items, 10 percent nylon articles and the balance of rayon, acetate, etc. The laundry to be conditioned occupies 40 percent of the dryer volume and the drying air is blown through the dryer at the rate of about 200 cubic feet per minute, at an initial temperature of about 70 C. The drum rotates at about a speed of 60 rpm. Initially the temperature of the damp laundry is low, approximately 20 C., but as drying continues, it increases to almost 70 C. The conditioning agent on the surface of the article is abraded off onto the surfaces of the fabrics being treated, so that when, after 50 minutes of drying, the machine is turned off and the laundry is removed, it is static-free and soft to touch, compared to a similar load in which the conditioning article is not used. The clothing treated exhibits no spots or stains and periodic examination of the conditioning article during the operation of the dryer shows that the coating is held satisfactorily to the base. There is no flaking or cracking of the conditioning composition evident.
On examination of the treating tape after use it is found that approximately 3 grams of conditioning composition have been abraded from the surface onto the fabrics to be treated. Therefore, the coated paper contains at least an additional 2 grams of available conditioning material and can be used again. When it is reused with another load of laundry and all the coating is abraded from the surface, only about l.5 grams of the original 6.5 grams of conditioning composition remains on the conditioning paper. At that time the tape is removed and replaced with a fresh strip and the conditioning operation is repeated with another laundry load.
In other runs, using the same type of coated paper, nylon articles are removed after 5 minutes and permanently pressed articles are withdrawn after minutes and are found to be with each I satisfactorily conditioned, being soft, static-free and wrinkle free.
When, instead of employing the formula described above there is used a melt of lauric monoethanolamide and stearic diethanolamide, also in 30:70 portions, comparable results are obtained. Similarly, when a solution comprising 30 percent ethanol, 55 percent distearyl dimethyl ammonium chloride and I5 percent water is employed to coat the same type of tape at approximately the same weight of conditioning composition per unit area and the tape is employed as described above, good softening of cotton and antistatic action on synthetic organic polymeric textiles are obtained. When synthetic organic anionic surface active agents, such as sodium lauryl sulfate and soap, are also used, applied in the same quantities, either as melts or solutions, to toweling of the type described above and with the same type of adhesive, they are also found to be satisfactory in conditioning of the tested laundry. It is generally observed that additions of plasticizing agents, such as those described in a patent application filed by P. J. Falivene on the same day as this application and entitled FABRIC CONDITIONING WITH IMPROVED COMPOSI- TION CONTAINING A PLASTICIZER, are useful in improving even further the nonflaking characteristics of the conditioning agents, so as to prevent any spotting or staining of the treated materials. 7
When the above experiments are repeated, using other means for holding a strip of coated paper of the same type and size to the interior of the dryer drum, at a location between baffles, with the strip extending longitudinally, similar results are obtained. Such means for holding the strip include transparent sealing tapes, rubber cements, glues, round head screws with washers, and clamps. Generally, metal parts are avoided when employing the cationic conditioning agents, because they sometimes cause stainings by chemical reactions with metal ions, such as iron ions.
EXAMPLE 2 The experiments reported in example 1 are repeated, using form-retaining bases of various shapes and sizes held to the dryer wall in substantially longitudinal disposition at midpoints between the baffles or ridges. The shapes which are used include cubes, slabs, cylinders, cylindrical tubes and boxes. All have an external surface of about 50-300 sq. cm. and most extend from 10 to 30 cm. across the dryer drum. They are constructed of polystyrene foams, paperboard or wood.
The conditioning effects obtained are noticeable with all such form-retaining bases. The clothes treated are softer, of lower electrostatic action and have fewer wrinkles than do control items. Of course, better conditioning is obtained from those articles having greater surfaces from which more conditioning agent is applied to the laundry. It is noted that there is a lesser tendency for cracking or flaking of conditioning composition from the surface of the base when the shape thereof is such that sharp corners are avoided. After conclusion of the conditioning operation articles are easily located and removable from the dryer.
What is claimed is:
I. An apparatus for conditioning fibrous materials which comprises an automatic laundry dryer drum or similar container for fibrous materials, means for rotating the drum and tumbling fibrous materials contained therein and, held to an interior wall of the drum, in form-retaining relationship therewith, a base, having an exterior surface thereof a conditioning agent for the fibrous materials, which, on contact with such tumbling materials is removable from the base and depositable on the materials in sufficient quantity to condition them said base comprising a flexible material and having a pressure sensitive adhesive on the opposite surface thereof to effect said form-retaining relationship.
2. An apparatus according to claim 1 comprising means for passing heated air through the fibrous materials in the drum and in which the drum is of form-retaining material.
being a surface active synthetic organic fabric softener which, under the conditions of automatic laundry drying, elevated temperature, high humidity and repeated contact with tumbling moist laundry, is gradually deposited on the tumbling laundry brought into contact with it, and the pressure sensitive adhesive holds sufficiently to the interior wall of the dryer drum under the conditions of drying of laundry to maintain the strip or sheet of base material in form-retaining contact with said interior wall.