US2501988A - Method for the treatment of fabric, yarns, threads, strands, and the like to render rubberized articles made therefrom more durable - Google Patents

Description

Patented Mar. 28, 1950 METHOD FOR THE TREATMENT OF FABRIC,

YARNS, THREADS,

STRANDS,

AND THE.

LIKE TO RENDER RUBBERIZED ARTICLES MADE THEREFROM MORE DURABLE Malcolm R. Buifington, Millburn, N. 1., assignor to Lea Fabrics, Inc., Newark, N. J., a corporatlon of Delaware No Drawing. Application May 17, 1946, Serial No. 670,544

16 Claims. 1

The present invention relates to a. method for the treatment of fabric and more particularly to a method and product in which methyl cellulose is employed in a, manner to impregnate a fabric without clogging themesh and serving to protect the fabric in various products hereinafter described against deterioration by heat, hot water, salt water, oil and other chemicals.

The present invention is a continuation in part of my application Serial No. 342,824, filed June 27, 1940, and issued May 21, 1946, Patent No. 2,400,530, for Method of making ring type packings.

The method as described in the said application includes the steps of saturating a fabric with a methyl cellulose solution, preferably of about 2% strength, which serves to penetrate the threads of the fabric without clogging the meshes of the fabric when dried. The impregnated fabric is then dried, after which it is impregnated with neoprene, or other vulcanizable rubber cement containing synthetic rubber and compounding ingredients to fully saturate the fabric. The

fabric so trated is then formed into cylinders and molded, being vulcanized under heat and pressure in the usual manner.

As disclosed in the said application, methyl cellulose is not soluble in solvents used in connection with the compounding of hard rubber compounds, and is insoluble in hot water, so that if the final product made therefrom is subjected to wear, and the fabric becomes exposed to oil and water at high temperatures, as in deep wells, for example, no deterioration of the fabric takes place, whereas if the fabric were untreated with methyl cellulose the fabric would rapidly deteriorate and disintegrate under such conditions of exposure. The use of methyl cellulose in the fabthrough the meshes of the fabric, so that the fabric layers are united through thin layers of rubber composition on each face of the fabric,

which are united into an integral mass by the rubber composition passing through the meshes of the fabric.

It has been discovered that the method involving the use of methyl cellulose impregnations in fabric is applicable to a variety of uses with beneficial and improved results, resulting in superior properties in the articles produced, as hereinafter described in detail.

pile fabrics.

The present invention is applied particularly to the making of cemented pile fabric by the use of the machine illustrated and described in the Patent No. 1,784,552 to Smith et al., issued December 9,1930, for Machine for production of In brief, the method involves the use of fibers such as goat hair fibers which are fed over separator elements on a drinn and inserted between the separators by an inserting mechanism, after which a rubber cement or aque- "ous rubber dispersion is sprayed or otherwise applied onto the base or exposed portion of the fibers and a base fabric such as burlap is applied to the cemented base of the formed loops, produced by the inserting mechanism, after which the rubber cement is vulcanized while the loops are held in place between the separators and the material is then withdrawn from between the separatorsand the tops of the loops sheared to form the cemented pile fabric. The pile fabric produced may be employed on ordinary floors and is frequently used on cement floors or floors which contain oil the manufacture and construction of automobile tires or other rubber tires.

One of the objects of the invention is to provide a method for the treatment of fabric in a manner so as not to interfere with the usual manufacturing processes in the making of an article therefrom and which will withstand action of hot water, oils and other solvents and chemicals to which the article may be exposed in ordinaryuse.

Another object of the invention is to provide a method for the treatment of a base fabric having meshes which are more or less open and which is impregnated with a rubber cement in the making of an article such as a cup ring used in pumping operation in oil wells, fabric such asin the making of a rubber hose, cord fabric such as in the making of tires, and jute or other fabric employed in the manufacture of cemented pile fabric.

Another object of the invention is to provide a method for the treatment of fabric which may be employed for various purposes in the manufacture of articles in which rubber is employed,=and which will withstand oily or greasy materials of animal,

vegetable or mineral origin and which is stable poses without deterioration when and if a pcrtion of the fabric becomes exposed during use and wear of the article.

Another object of the invention is to provide a method for the treatment of base fabrics employed in the construction of various articles of commerce which is adapted to greatly prolong the life of the article under ordinary conditions of use or under extreme conditions of exposure to temperature or reactive chemicals.

With these and other objects in view, the invention comprises the various features hereinafter more fully described and defined in the annexed claims.

The invention may be generally described first as applied to the making of a cemented pile fabric. 7

A jute or burlap backing as applied in the method above generally described may be employed in the making of pile fabric by the machine illustrated in Patent No. 1,784,552.

It will be understood that untreated jute-is easily dried out and is tendered by heat, such as the temperatures employed in vulcanizing the rubber which is associated with the jute and employed in the manner described in detail in the said patent. In applying the method of the present invention to the method of making pile fabrics as described in the said patent, the jute or burlap is first treated with a solution of methyl cellulose, such as a 2% solution, for example. The methyl cellulose solution may be sprayed onto the base fabric so as to penetrate into the fibers of the threads of the fabric, or it may be immersed by passing through a tank containing the solution of methyl cellulose in accordance with the ordinary method of immersion. Prior to the treatment with the methyl cellulose solution, the base fabric, which is generally. provided in large rolls of from 3 tab feet in width, may be first treated with a wetting agent such as Emulphor-O, or with any other suitable wetting agent adapted to penetrate into the interstices of the threads composing the fabric so as to readily absorb or take up the methyl cellulose solution with which the fabric is to be impregnated. Emulphor O is the trade name of a commercial wetting agent or stabilizer which is a condensation product of ethylene oxide and higher alcohols and may be made by the methods of the examples as set forth in the Schoeller et a1. Patent No. 1,970,578, issued August 21, 1934. While the use of "Emulphor-O is preferred as the wetting agent, other suitable wetting agents may be used, such as sodium isopropyl naphthalene sulfonate, or the sodium salts of succinic acid derivatives, such as Deceresols, for example. The wetting agent may be used in a proportion of A% to 1% in water. If desired, the wetting agent may be included in the proportion of from 4% to 1% in the methyl cellulose solution, and the fabric after immersion therein may be squeezed between rollers or otherwise partially dried or completely dried by exposure to air or treatment in any suitable drying apparatus. The methyl cellulose serves to impregnate the fibers and threads of the fabric without clogging the interstices of the fabric, so that when a rubber cement of suitable properties is applied to the fabric, it impregnates and coats the fabric to form a substantially continuous surface. The base fabric to be used in the manufacture of cemented pile fabric is then coated on one side, or sprayed with, On one surface thereof, a vulcanizable rubber cement, such as aqueous rubber dispersion, for example, and is then dried or partially dried, so that when it is applied to the bases of the loops held between the separators of the drum of the Smith et a1. machine, above referred to, the fabric strongly adheres to the bases of the loops which have previously been similarly treated with a vulcanizable rubber cement or a compounded aqueous rubber dispersion. A vulcanizing press is then applied to the base fabric for a sufficient length of time to vulcanize the rubber cement at thebases of the loops, which forms a continuous strong binding medium between the loops of goat hair or other fibers employed and the fibers 0f the fabric base, such as burlap. After the loops have been withdrawn from between the separators of the drum, they are preferably sheared or suitably opened and the pile fabric is completed in the usual manner. Sections of the pile fabric produced may be cemented together for floor coverings or the like by the use of fabric strips a few inches in width applied underneath the fabric sections at the seams to be joined. The fabric strips which are used in the joining operation may be treated in a manner similar to that applied to the base fabric by treatment with a methyl cellulose wetting agent solution, drying and applying a rubber cement to the face of the fabric strip which is to be used against the underside of the fabric sections to be joined.

When sections of fabric thus produced are exposed to high temperatures, or to chemicals, such as solvents, oils, dilute acids or alkalies, there is substantially no penetration of the oil or chemical into the body of the fabric, and the fabric material produced as above described is rendered highly wear-resistant under substantially all conditions of use. The pile fabric product made in the manner above described is particularly useful where moisture is present and on concrete floors where alkaline conditions frequently exist due to the lime compounds in the cement and the presence of moisture. The pile fabric product is also particularly useful on the front floor of automobiles where it is frequently subject to the action of oil and moisture, as well as to heat from the engine and from the car-heater.

In applying the invention to the making of valve cup rings and ring packings, a base fabric is first treated with methyl cellulose of about 2% strength, with or without a wetting agent, the

fabric being preferably first immersed in the solution and then dried, by which the methyl cellulose penetrates into the fibers of the threads and serves as a protecting agent. After the fabric has been suitably impregnated with the methyl cellulose material, it is then impregnated and coated with a rubber cement composition of the following formula, for example:

' Partsby weight Neoprene Carbon black 40 Zinc oxide 5 Magnesium oxide 4 Neozone D (anti-oxidant) 2 Cottonseed nil 5 This compound when applied to a methyl cellulose treated fabric and vulcanized in a solid slab has a hardness of about '70 on the Shore hardness gauge, and may be used in ring packings in oil wells up to a depth of about 1,000 ft. A hardness varying from about 55 to 75, produced by varying the above composition in known manner, is well suited for the production of this article of manufacture, as more fully described in my said Patent No. 2,400,533.

It will be understood that in the making of various articles or products using a methyl cellulose treated fabric as a base, the method may be modified to some extent to obtain variations in the product, depending on the particular use to which it is to be put. The base fabric, in addition to treatment with methyl cellulose, may also contain a suitable resin, such, for example, as a water soluble urea-formaldehyde resin, the fabric being impregnated in substantially the same way as above, described in connection with the use of the methyl cellulose solution, and dried thereafter to impregnate or coat the fibers of the threads of the fabric without filling or clogging the ineshes thereof. It will be understood that theurea-formaldehyde resin above referred to is thermo-setting at the temperatures used for the vulcanization of the synthetic rubber or binder composition, the reaction proceeding rapidly so that the fabric becomes relatively stiff almost immediately and forms a support, or a relatively inflexible base, during vulcanization and prevents the forming of wrinkles in the side walls or surfaces of the article produced by a molding operation. By the use of a synthetic resin in addition to impregnating by means of methyl cellulose, fabrics having a more open weave and greater original flexibility may be employed in the making of articles, particularly rubberized articles, by which rubber coatings intermediate between layers of overlapping fabric portions are united to form a unitary structure in which pins or projections of the rubber composition pass through the meshes of the fabric to unite the adjacent layers of the binder composition, thus producing a more resistant structure. In the treatment of the fabric impregnated with methyl cellulose and a resin, as above described, the fabric is preferably impregnated and coated with a rubber composition to penetrate the meshes of the fabric, the amount of the rubber composition per square yard of the fabric being preferably substantially equal to the weight of the fabric to be coated or impregnated, although the amount may be varied within wide as will be understood by those skilled in the art. In the making of articles having the methyl cellulose, treated fabric as a base, a considerable variety of operations may be employed which cannot be permitted in articles having an untreated fabric as a base. In the making of cup rings or other articles which are to be exposed to water, oil or other chemicals, the article made in accordance with the method of the present invention may be drilled or perforated so that in ordinary use the perforated portions are subjected to oil, hot water or other normally deteriorating agents without detrimental action on the article. 7

In applying the method of the invention to the making of hose, a tube of rubber may be covered with plies of fabric which have been treated by impregnation with a methyl cellulose solution,

canized in a hose press, or is wrapped with strips of fabric over the outer rubber layer and vulcanized at the proper temperature in open steam.

In the making of belting or other articles plied up in sheets, a fabric which has been treated with a methyl cellulose solution as above described or additionally treated with a synthetic resin, may be coated with a vulcanizable rubber cement and then vulcanized between plates to form a reenforced sheet packing, or plied up in sheets to form the belting or other desired articles. The methyl cellulose treated fabric may also be employed for the making and construction of tires in accordance with the generally known method. In the manufacture of tires from butadiene-styrene copolymers, the fabrics are usually treated with a water dispersion of whole tire reclaim, or a buta- 'diene-styrene latex, before calendering to promote adhesion of the calender coating to the fabric. Such impregnating compounds usually contain a high'percentage of casein to increase the adhesion of the impregnant to the fabric. By treatment of the fabric employed with a methyl cellulose solution in the manner above described,

preferably with a wetting agent, adhesion of the rubber impregnating coat is increased to the point where the casein may be greatly reduced in amount, or may even be entirely eliminated. The substantial reduction or elimination of caseinin the 'process is of particular advantage for the reason that casein is subject to putrefaction in a tire under normal conditions, which is enhanced under conditions of high humidity and temperature. By the use of methyl cellulose in the fabric employed in the tire, it is rendered inert to such action and adhesion of the synthetic rubber is increased so that the use of casein becomes substantially unnecessary or may be greatly reduced in amount, thus greatly increasing the mileage and life of the tires.

Tires made from butadiene-styrene polymers generate more heat than those made from natural rubber, and in the processes heretofore used cotton fabric is tendered to such an extent that it has been found advisable to substitute rayon for the cotton. By treatment of the cotton fabric carcass with a methyl cellulose solution so as to penetrate the fibers without clogging the interstices of the fabric when dried, in the manner above described, the cotton fabric in the tire made with butadiene-styrene polymers or other syn thetic rubber, retains its tensile strength at the temperatures produced or generated under the usual speeds of operation and does not deteriorate as in tires made with a cotton carcass and synthetic rubber in accordance with the methods heretofore employed.

It will be understood that methyl cellulose em-' ployed as an impregnating agent for fabrics proor with a methyl cellulose solution containing a duces marked advantageous results because of its insolubility in most organic solvents, being unaffected by oily or greasy materials and being stable to all-:aiies and dilute acids, and being insoluble in hot water. Solutions of methyl cellulose in water will gel at varying temperatures depending on the concentration of the solution and the viscosity of the particular form of methyl cellulose employed. The temperature of gelation of the methyl cellulose may be lowered by certain agents, such as by the addition of chlorides, sulphates, or nitrates, for example. The gelation temperature may be raised, however, by the addition or other reagents, such as thiocyanates or iodides, for example. In a 4% solution of low viscosity methyl cellulose, the maasouoss 7 terial will gel at a temperature of about 57 C., while a similar 4% solution of methyl cellulose of medium viscosity will gel at a temperature of about 51 C.

In processing and applying rubber to methyl cellulose-treated fabrics, it is obvious that solvent solutions of rubber would have no effect on the methyl cellulose in and on the fabric. In treating the impregnated fabric with water dispersions of rubber, of nitrate, such as calcium nitrate, for example, or some other salt which is a coagulant for the dispersion of rubber, may be added to the methyl cellulose impregnant which will lower the gel point and coagulate the surface disperson before it can dissolve any of the methyl cellulose on the fabric. If desired, the fabric and rubber disperson may be preheated above the gelation point of methyl cellulose during the coating operation with rubber.

It will be understood that in the vulcanization of rubber, gases are generally released which are frequently injurious to fabrics and produce a tendering or deteriorating action on the fabric employed, such as cotton fabric, for example. Such action is greatly reduced when fabrics treated with methyl cellulose in the manner above described are employed in association with rubber during the vulcanization process by the method above described, in the production of various rubberized articles.

In applying the invention above described to the making of rubber hose, tires, fabrics and other articles of manufacture, I may first impregnate or treat yarns, threads, cords, strands and the like with a methyl cellulose solution, so as to render the same impervious to oils and otherchemicals, prior to weaving the yarns, etc. into the fabric, cord fabric or other assembly of yarns, etc. to beemployed in the article to be produced.

In the manufacture of cord fabric to be used for the making of tires, for example, in which the main cords are held together by only a light crossthread spaced at fairly wide intervals, it has been found particularly advantageous to treat the yarns, cords or threads of cotton or other fibers, after the spinning operation but before being woven into a fabric, with a solution containing from 1% to 5% of methyl cellulose and preferably a so from /1% 1% of a wetting agent, the

method of treatment and impregnation being substantially the same as that above described to render the yarns, cords or threads resistant and substantially impervious to oils and other chemicals, which without such treatment would be attacked by oils and various chemicals and would be tendered in the presence of synthetic rubber at temperatures developed at normal and high speeds of operation of tires made therefrom. It is to be understood, therefore, that the methyl cellulose treatment may be applied directly to the fabric to be used in making the tires, or to the cords or strands which are to compose the fabric prior to the weaving operation by which the fabric is produced.

In the manufacture of rubber hose, also, it is generally advantageous to first impregnate the yarns or strands, which are to be woven into the fabric to be used, prior to the weaving operation with a methyl cellulose solution in the manner above set forth, after which the yarns or strands are at least partially dried and then woven into the fabric. In the making of the rubber hose, the resulting fabric is then treated with a vulcanizable rubber cement, preferably'containing r 8 synthetic rubber, which serves to impregnate and to coat the fabric. A tube of rubber is then covered with'plies of the treated fabric by wrapping it in helical form over the rubber tube, after which an outer sheet of rubber is wrapped around the assembly and a continuous strip of wet fabric is then wrapped over the outer rubber layer to exert pressure on the rubber jacket during the vulcanlzing step. The vulcanizable rubber of the assembly is then vulcanized in open steam to form a fabric reenforced rubber hose. After the vulcanization of the rubber is completed, the outer fabric may be peeled off or removed from the hose. The method may be modified, if desired, by weaving a fabric jacket around the tube of rubber from yarns or strands which have been impregnated with methyl cellulose, rather than wrappin the tube of rubber with plies of the fabric in helical form as above described, thereafter impregnating the woven fabric jacket with a vulcanizable rubber composition, covering the impregnated fabric with rubber and vulcanizing the unvulcanized portion of the rubber. It will be understood that in some cases, such as in the making of fire hose, for example, an outer fabric layer or fabric jacket impregnated with methyl cellulose in the manner above described may also be employed.

By the term "rubberized article employed in the claims annexed hereto is meant an article or product containing or including rubber either as natural rubber, synthetic rubber or. a mixture of natural and synthetic rubber or reclaimed rubber in its composition.

It is to be understood that various changes or modifications may be made in the method and products described herein without departing from the spirit or scope of the invention as defined in the annexed claims. It will be understood, for example, that in the production of the cemented pile fabric product in accordance with the method described in detail herein, the fabric backing containing burlap or other open weave fabric, such as cotton, or canvas, may be further treated by applying a light coating of rubber on the back of the fabric, as by spraying, for example. to render the pile fabric product non-skid. Such a coating may be applied to joined sections of cemented pile fabric, for example, without heat vulcanization of the added coating, an accelerator being added to produce vulcanization at room temperature without further heat treatment. Various other changes within the skill of the ordinary person skilled in the art may obviously be made in the various methods and products above described and are contemplated to be within the invention as defined by the annexed claims.

Having thus described the invention, what is claimed as new is:

l. A method for the manufacture of a rubberized article which comprises treating a fabric with a solution of methyl cellulose so as to penetrate the threads thereof without clogging the meshes of the fabric when dried, drying the fabric, impregnating the fabric with a rubber cement composition and vulcanizing the rubber.

2. A method for the manufacture of a rubberized article containing synthetic rubber which comprises treating an open mesh fabric with a solution of methyl cellulose and a wetting agent to penetrate the threads of the fabric without clogging the meshes thereof when dried, at least partially drying the fabric, impregnating the fabric with a compounded rubber cement con- 9 taining synthetic rubber and vulcanizing the rubher.

3. A method for the manufacture of a rubber ized article reenforced by an open weave flexible fabric which comprises treating an open weave flexible fabric with a solution containing from 1% to of methyl cellulose of low viscosity to 1 whichat least onehalf of the rubber'is synthetic,

molding the article and vulcanizing the rubber therein.

4. A method for the manufacture of a rubberized article containing synthetic rubber which comprises treating an open mesh fabric with a solution containing 1% to 5% of methyl cellulose and 14% to 1% wetting agentto penetrate the threads thereof without clogging the meshes of the fabric when dried, at least partially drying the fabric, impregnating the fabric with a compounded rubber cement containing in excess of 50% of a synthetic rubber and vulcanizing the rubber.

. 5. A method for the manufacture of a rubberized article reenforced by an open weave flexible cotton fabric which comprises treating an open weave flexible fabric with a solution containing substantially 2% of methyl cellulose and from to 1% of a wetting agent to penetrate the threads of the fabric without clogging the meshes thereof when dried, drying the fabric to a low moisture content, impregnating the fabric with a solution containing a thermosetting resin without clogging the meshes of the fabric when dried, at least partially drying the fabric, impregnating the thus-treated fabric with a compounded rubber cement composition containing at least 50% of synthetic rubber, molding the article'and vulcanizing the rubber therein.

6. A method for the manufacture of a rubberized article reenforced by an open weave flexible fabric which comprises treating an open weave cotton flexible fabric with a solution containing from 1% to 5% of methyl cellulose and from to 1% of a wetting agent to penetrate the threads of the fabric without clogging the meshes thereof when dried, drying the fabric to a low moisture content, forming reenforcing layers of the fabric in the form ofv the article to be produced therefrom, impregnating the fabric layers with a solution containing a urea-formaldehyde resin without clogging the meshes of the fabric when dried, at least partially drying the fabric, impregnating the thus-treated fabric with a butadiene-styrene latex composition, drying and molding the article, and vulcanizing the rubber composition therein.

7. A method for the manufacture of a synthetic rubber tire as a rubberized article from a rubber composition containing butadiene-styrene copolymers, which comprises treating an open weave flexible cotton fabric with a solution of methyl cellulose so as to penetrate the threads thereof without clogging the meshes of the fabric when dried, drying the fabric to a low moisture content, treating the fabric with a butadiene-styrene latex containing a low percentage of casein sufficient in amount to increase the adhesion of the impregnant to the fabric but insufficient in amount to cause putrefaction under normal con- I a 10 ditions, forming a tire carcass with said fabric, coating the tire carcass with a rubber composition containing. a butadiene-styrene copolymer and molding the rubberized article in, a tire mold under heat and pressure.

8. A methodfor the manufacture of pile fabric which comprises inserting a continuous batt of fibers between and over separator elements to forma series of loops having the bases thereof exposed on.the separators, applying to the exposed bases of the loops a solution of methyl cellulose to penetrate into the bases, at least partially drying the fibers, impregnating the said bases of the loops with a vulcanizable rubber cement, treating a fabric base to be applied to the bases of the loops while held between said separator elements with a solution of methyl cellulose, at least partially drying the thus treated fabric, coating one side of the said base fabric with a vulcanizable rubber cement, applying the coated side of the fabric to the.bases of the loops while held between and on the said separators, vulcanizing the rubber while the base fabric is held in place on the said bases of the loops, removing the vulcanized product from between the separators and opening the loops to form the pile fabric.

9. Amethod for the manufacture of a pilefabric product which comprises inserting a batt of goat hair fibers between and over the separator elements of a drum by means of an inserting mechanism to form a series of loops having exposed bases, applying to the exposed bases of the loops a solution containing methyl cellulose and a wetting agent to penetrate into said bases without clogging the interstices between the fibers when dried, at least partially drying the fibers, impregnating the said bases with a compounded rubber cement containing at least.50% of synthetic rubber, similarly treating a base fabric to be applied to the said bases with a solution of methyl cellulose and a wetting agent without clogging the pores of the fabric when dried, at least partially drying the thus-treated fabric, coating one side of the said base fabric with a vulcanizable rubber cement containing at least 50% of synthetic rubber, applying the coated side of the fabric to the bases of the loops while held between and on the said separators, vulcanizing the said rubber cement with the base fabric in place, removing the vulcanized product from between the separators and opening the tops of the loops to form a pile fabric product.

10. A method for the manufacture of a pile fabric product which comprises inserting a batt of fibers between and over the separator elements circumferentially spaced on a drum by means of an inserting mechanism to form a series of loops having the bases thereof exposed in a continuous surface over said separator elements, spraying on the said exposed bases of the loops a: solution containing methyl cellulose and an inorganic salt which is a coagulant for an aqueous dispersion of rubber, at least partially drying the fibers, treating the fibers with an aqueous dispersion of rubber, similarly treating a fabric to be applied to said bases with a solution at least partially drying the said coating, uniting the coated fabric with the bases of the loops while the loops remain held between and over said separator elements, vulcanizing the rubber and removing the pile fabric product from said separator elements.

11. A method for the manufacture of a pile fabric product which comprises inserting a batt of goat hair fibers between and over separator elements circumferentially spaced on a drum to form a series of loops having the bases thereof exposed in a continuous surface over said separator elements, treating the exposed bases of the loops with a solution containing methyl cellulose and a wetting agent, forming a coating of an aqueous rubber dispersion containing synthetic rubber on the said bases of the loops, immersing aburlap base fabric in a solution of methyl cellulose containing from 1% to 5% of methyl cellulose and from 3 4 to 1% of a wetting agent, at least partially drying the base fabric and the coating on the bases of the loops, coating one side of the burlap with an aqueousrubber dispersion containing synthetic rubber, uniting the coated side of the burlap with the coated bases of the loops while the loops remain held between and over said separator elements, vulcanizing the rubber of the joined coatings while the loops remain held between said separator elements, re-

' moving the pile fabric product from between the 14. A method for the manufacture of rubber hose which comprises forming a woven fabric of flexible open weave in which the constituent 15. A method for the manufacture of a rub- I berized article which comprises treating a strand of fibers with a solution of methyl cellulose so as to'penetrate the fibers of the strand and to render it substantially impervious to oils and other chemicals when dried, at least partially drying the strand, weaving an open mesh fabric therefrom, impregnating the resulting fabric with a rubber cement composition and vulcanizving the rubber cement composition.

said separators and opening the tops of the loops.

12. A method for the manufacture of a rubber hose which comprises treating a fabric by impregnation with a solution containing about 2% of methyl cellulose and to 1% of a; wetting agent, at least partially drying the fabric, covering a tube of rubber with plies of the said fabric wrapped in helical form, wrapping the assembly with an outer sheet of rubber and vulcanizing the assembly in a hose press at a vulcanizing temperature to form the rubber hose.

13. A method for the manufacture of rubber hose which comprises immersing a woven fabric in a solution containing from 1 to 5% of methyl cellulose and from V4% to 1% of a wetting agent, at least partially drying the fabric subsequent to immersion, treating the fabric with a compounded rubber cement containing synthetic rubber to impregnate and coat the meshes of the fabric, covering a tube of rubber with plies of said treated fabric by wrapping said fabric in helical form over said rubber tube, wrapping the assembly with an outer sheet of rubber, wrapping a continuous strip of wet fabric over said outer sheet of rubber to exert pressure thereon, vulcanizing the .rubber in open steam to form a fabric reenforced hose and removing the outer fabric strip after completing the vulcanization.

fill

16. A method for the manufacture of a rubberized article which comprises impregnating a strand composed of vegetable fibers with a solution containing from 1% to 5% of methyl cellulose so as to penetrate the fibers of e strand. at least partially drying the strandfweaving an open mesh fabric from the resulting strand, impregnating the fabric with a vulcanizable rubber cement composition containing at least 50% of synthetic rubben-molding the rubberized fabric into the form of an article and vulcanizing thesaid rubber cement composition.

- MALCOLM R. BUFFINGTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Num er Name Date 1,045,346 Whalen 1 Nov. 26, 1912 1,784,552 Smith et al. Dec. 9, 1930 1,970,578 Schoeller Aug. 21,1934 2,010,061 Curtiss Aug. 6, 1935 2,107,852 Bolton Feb. 8, 1938 2,235,798 Collings et al. Mar. 18, 1941 2,400,533 Buffington May 21, 1946

Claims (1)

1. A METHOD OR THE MANUFACTURE OF A RUBBERIZED ARTICLE WHICH COMPRISES TREATING A FABRIC WITH A SOLUTION OF METHYL CELLULOSE SO AS TO PENETRATE THE THREADS THEREOF WITHOUT CLOGGING THE MESHES OF THE FABRIC WHEN DRIED, DRYING THE FABRIC, IMPREGNATING THE FABRIC WITH A RUBBER CEMENT COMPOSITION AND VULCANIZING THE RUBBER.