US2720476A

US2720476A - Hard surface floor and wall covering having a beater saturated backing

Info

Publication number: US2720476A
Application number: US261636A
Authority: US
Inventors: John W Baymiller
Original assignee: Armstrong Cork Co
Current assignee: Armstrong World Industries Inc
Priority date: 1951-12-14
Filing date: 1951-12-14
Publication date: 1955-10-11
Anticipated expiration: 1972-10-11

Description

W 1 @1111 M W515 -1. W. BAYMILLER mfififflm HARD SURFACE FLOOR AND WALL COVERING HAVING A HEATER SATURATED BACKING Filed Dec, 14. 1951 INVENTOR JOHN W- BAYMILLER ATTORNEY United States Patent HARD SURFACE FLOOR AND WALL COVERING HAVING A BEATER SATURATED BACKING John W. Baymiller, Manheim Township, Lancaster County, Pa., assignor to Armstrong Cork C ompany,

Lancaster, Pa., a corporation of Pennsylvania Application December 14, 1951, Serial No. 261,636

6 Claims. (Cl. 1544.9)

This invention relates to a floor and wall covering, and more particularly to a floor or wall covering comprised of a wear resistant decorative facing disposed on a fibrous foundation or backing obtained by depositing the solids content of a synthetic rubber latex onto fibers suspended in a slurry and forming the resulting slurry of coated fibers into a sheet. Such a backing material is water resistant and is substantially nonbleeding or nonstaining under normal conditions of manufacture. By the term normal conditions of manufacture I mean the conventional conditions of pressure and heat used in the manufacture of linoleum or similar hard surface floor coverings, such as those containing a plastice composition wearing surface.

In the floor covering art, the manufacture of resilient flooring such as linoleum is conducted by a method which comprises saturating the base or foundation with asphalt to render it water resistant and to increase its strength. Asphalt is not particularly desirable for this purpose, since in the stoving or curing operation required to cure the wearing surface or facing layer, the asphalt frequently bleeds through into the wearing surface. To overcome this undesirable characteristic of the asphalt, it has been common practice to apply seal coatings to both sides of the saturated foundation. Such coatings are designed to seal the asphalt Within the foundation; however, in many cases, the asphalt bleeds through the seal coating when heat and pressure are applied in the manufacture of the covering. Moreover, such coatings bleed through during the stoving or curing operation, particularly into the uncoated edges of the backing material.

For example, in the manufacture of molded inlaid linoleum, granulated linoleum composition is placed on an asphalt saturated felt base provided with seal coating and disposed under a heated hydraulic press, which serves to compact the granular composition and adhere it to the base. The coated carrier is then placed under a second heated hydraulic press and subjected to heat and pressure to smooth and secure a satisfactory face on the goods. Under the conditions of heat and pressure required for operation, the asphalt saturant is softened and squeezed through the linoleum composition, staining the same. In many instances, the asphalt adheres to the press, thus rendering the covering difficultly removable and staining or discoloring other portions of the backing subsequently disposed in the press.

Asphalt is somewhat brittle, and hence coverings in which it is used as a saturant for the base are not as flexible as desired. This characteristic of asphalt saturant is particularly undesirable in regions where the temperature fluctuates over a wide range, and in cold regions; for, before the rolled covering can be used, it is necessary that it be heated or warmed to an extent sufficient to soften the asphalt to permit the covering to be unrolled. If this is not done, the brittle sheet cracks and breaks during the unrolling and installation operations.

A further disadvantage in the use of asphalt as a saturant for the base or foundation of floor or wall coverings resides in the fact that an asphalt saturant does not appear to increase the strength of the foundation during the temperatures encountered in the stoving operation. Occasionally, when the covering is stoved vertically, difiiculty is experienced with the covering tearing and falling in the stoves. This necessarily increases the cost of the covering. In order to render the base water resistant to a satisfactory degree, a large amount of asphalt must be used per square yard of covering, which again increases the cost of the covering and is particularly. undesirable in that it greatly increases staining of the facing by bleeding of the asphalt therethrough, even though seal coatings are used.

In order to overcome the numerous undesirable features connected with the use of asphalt saturated felt backing for resilient floor coverings, there have been proposed various other saturants, such as those comprised of various resins and drying oils dispersed in a solvent. Included among these saturants are plasticized tall oils dispersed in a solvent. While such saturants have overcome to a large extent the bleeding problem presented by asphalt saturants, they present additional difiiculties. For example, due to the presence of a solvent, the impregnation step is quite hazardous, and unless carefully controlled, may result in fire because of the nature of the treatment necessary to thoroughly impregnate the felt. In addition, the stoving of floor coverings having such an impregnated felt backing is a hazardous operation because of the combustibility of the composition utilized as the saturant or the exothermic nature of the reaction which takes place in the stoves. Thus, fires may result in the stoves, destroying a very large quantity of material. This, of course, is a costly loss, inasmuch as a linoleum stove contains considerable quantities of goods which are cured at one time. If the goods are not totally destroyed by fire, the fumes so damage the remaining goods that they cannot be sold as first-grade material.

I have found that a backing material for resilient floor and wall coverings which is characterized by unusual flexibility and which is free from the disadvantages mentioned hereinabove may be prepared by disposing the solids content of a synthetic rubber latex onto fibers While contained in a slurry, and thereafter forming the resulting slurry into a sheet. In order to obtain the desired characteristics for a backing for linoleum or similar floor coverings, I have found it to be advantageous to utilize a furnish which contains particular types of fibers and finely divided solids in particular proportions. For example, the furnish to be beater saturated advantageously contains about 50 to parts by weight of cellulose fibers. These cellulose fibers may be any of a number of commercially available cellulose fibers, such as kraft paper fibers. In addition to the cellulose fibers, the furnish contains about 5 to 50 parts by weight of finely divided cork particles, advantageously those classified in the art as 60 to dust cork. By 60 to dust cork is meant a mass of cork particles which pass through a 60 mesh U. S. standard screen in a standard sieve analysis.

Another important consideration to be observed in the practice of my invention is the maintenance of the proper ratio of rubber to furnish. In order to obtain the desired characteristics for a floor covering backing, I have found that the ratio should be about 20 to 50 parts by weight of rubber to parts of furnish in the slurry which is subjected to treatment to deposit the solids content of the latex onto the fibers.

In order to produce the saturated felt, a slurry of fibers is first formed and then treated with the salt of a polyvalent metal, such as aluminum chloride, aluminum sulfate, and the like. After treatment with the salt, an alkaline hydroxide, such as ammonium hydroxide, is added to the slurry to convert the metal salt present to metal hydroxide. Thereafter, the desired synthetic rubber latex is added to the slurry; and after agitation, due to the conditions obtaining in the slurry, the solids content of the latex is deposited upon the furnish. The resulting slurry of coated furnish is then formed into a sheet upon a conventional paper-making machine.

While a number of synthetic rubbers may be used as binders or saturants in the production of the beater saturated sheet which forms the backing of my floor covering, particularly advantageous results are obtained with rubberlike copolymers of butadiene with styrene or acrylonitrile. These materials are known to the art as GR-S synthetic rubbers and Hycar synthetic rubbers. Generally speaking, the rubberlike polymers contain about 50% to 75% by weight of butadiene, the remainder being styrene or acrylonitrile. A typical butadiene-styrene copolymer contains about 50% butadiene and about 50% styrene. The proportions necessary to produce the rubberlike polymers are well known to the workers in the synthetic rubber art and form no part of my invention. Any commercially available synthetic rubber of the butadiene-styrene or butadiene-acrylonitrile type may be employed as the saturant in the production of the backing material of my floor covering.

The production of the backing of my floor covering is illustrated in the following specific example:

Example 75 parts by weight of kraft fiber and 25 parts by weight of 60 to dust cork particles were suspended in 10,000 parts by weight of water. To the resulting slurry were added 12 parts by weight of Al2(SO4)a.18H-2O in solution form, and the resulting slurry was agitated to disperse the solution. 10.8 parts by weight of (NHQOH (28%) were then added to convert the A12(SO4)3.18H2O to Al(OH)a. 30 parts by weight (on a dry basis) of a butadiene-styrene copolymer with a butadiene content of about 50% in the form of a latex were then added. The resulting slurry was agitated to coagulate the copolymer onto the fibers. The slurry of coated fibers was formed into a sheet on a paper machine.

The beater saturated product formed in the manner recited above is defined as a water-resistant flexible sheet of substantially uniform structure consisting essentially of the felted and dried residue of a furnish of cellulose fibers and cork particles having uniformly deposited thereon a binder which consists essentially of the coagulated residue of a dispersion of synthetic rubber material.

In the production of a floor covering in accordance with my invention, the backing material, prepared as indicated above, is provided with the wearing surface, which may be linoleum composition or any of the plastic materials, such as vinyl chloride, vinyl acetate copolymer compositions, or blends of rubber and vinyl chloride polymers. Linoleum compositions are well known in the art and comprise pigment, filler, and linoleum cement, gen- 4 if a material of the belt base type is desired, the wearing surface may be a suitable paint coating such as an oleo= resinous varnish.

The floor covering of my invention is illustrated in the accompanying drawing, in which: 1 is the beater saturated felt backing, and 2 is the decorative wear resistant facing.

The floor and wall coverings mentioned in this specification are termed surface coverings in the art.

Among the advantages of my invention is the fact that the backing material presents no unusual hazard in its preparation. In addition, the floor covering may be stoved at elevated temperatures for considerable lengths of time without danger of fire due to combustion of the saturant or hardening of the backing. In addition, the material is exceedingly resilient and flexible and can be readily cut by conventional linoleum knives used in the installation of floor coverings of the type under consideration.

I claim:

1. A surface covering capable of being rolled and unrolled Without cracking comprising a water-resistant flex? ible foundation sheet of substantially uniform structure which consists essentially of the felted and dried residue of a furnish made up of about 50 to parts by weight of cellulose fibers and about 5 to 50 parts by weight of finely divided cork particles, with the individual fibers and cork particles of said furnish having uniformly de posited thereon about 20 to 50 parts by weight of a binder which consists essentially of the coagulated residue of a dispersion of synthetic rubber material, and a decorative wearing surface joined to the foundation sheet.

2. A surface covering in accordance with claim 1 in which tre decorative wearing surface is a layer of linoleum composition.

3. A surface covering in accordance with claim 1 in which the binder consists essentially of rubbery butadiene polymer.

4. A surface covering in accordance with claim 1 in which the binder consists essentially of rubbery butadiene-styrene copolymer.

5. A surface covering in accordance with claim 1 in which the binder consists essentially of rubbery butadiene-acrylonitrile copolymer.

6. A surface covering in accordance with .claim 1 in which the binder consists essentially of rubbery butadienestyrene copolymer and in which the decorative wearing surface is a layer of plastic material.

References Cited in the file of this patent

Claims

1. A SURFACE COVERING CAPABLE OF BEING ROLLED AND UNROLLED WITHOUT CRACKING COMPRISING A WATER-RESISTANT FLEXIBLE FOUNDATION SHEET OF SUBSTANTIALLY UNIFORM STRUCTURE WHICH CONSISTS ESSENTIALLY OF THE FELTED AND DRIED RESIDUE OF A FURNISH MADE UP OF ABOUT 50 TO 90 PARTS BY WEIGHT OF CELLULOSE FIBERS AND ABOUT 5 TO 50 PARTS BY WEIGHT OF FINELY DIVIDED CORK PARTICLES, WITH THE INDIVIDUAL FIBERS AND CORK PARTICLES OF SAID FURNISH HAVING UNIFORMLY DEPOSITED THEREON ABOUT 20 TO 50 PARTS BY WEIGHT OF A BINDER WHICH CONSISTS ESSENTIALLY OF THE COAGULATED RESIDUE OF A DISPERSION OF SYNTHETIC RUBBER MATERIAL, AND A DECORATIVE WEARING SURFACE JOINED TO THE FOUNDATION SHEET.