US2308429A - Flock finished fabric - Google Patents

Description

Patented Jan. 12,1943

.FLOCK FINISHED FABRIC Russell Grant Smith and Willis Johnson Physioc, J r., Stamford, Conn., assignors to Atlas Powder Company, Wilmington, Del., a corporation of Delaware No Drawing. Application August 9, 1939,

Serial No. 289,118

Claims.

The present invention relates to improvements in a flock finished fabric.

An object of the invention is to provide an improved flock finished imitation suede suitable for useas a leather substitute.

A further object is to provide an improved flock finished fabric which has high resistance to wear and soiling and which is relatively insensitive to solvents and is readily cleaned.

Another object of the invention is to provide a process for making improved flock finished fabric.

A still further object relates to an improved flock finished fabric which. can be given ornamental finishes not available in the'case of the ordinary fiock finished fabric. 1

Another object is to provide a process for ornamenting a flock finished fabric by souping and the product of such a process. a

The above and other objects will be' described more fully hereinafter.

It is well known in this art to produce a suede-.- like finish on a textile fabric-or other flexible: base material such as latex impregnated paper or felt by applying a coating of flock upon a foundation such as a layer of-ethyl cellulose prop:

itation to textile fabrics) results whenordin'ary flock finished fabric is coated on its surfacewith a coating of lacquer or enamel containing a slip agent and preferably also a pigment. The quan-' tity of material so applied is' highly important in obtaining this improved finish. The quantity mustbe such that it will not'obscureentirely the fibrous character of the surface so that the -re sulting fabric will still, have the suede-like finish which'is desired; On the other hand, the coating must be'present in such quantity as to penetrate erly plasticized, or natural or-synthetic rubber.

- Upon this foundation laid down ,inthe desired thicknessfin any suitableinanner', suchas by calendaring I or 1 spreading, an -anchoring coat is spread and upon it, while still. in a tacky condition, is sifted or new 'acoatlngof fine-flock of cotton, rayon, wool ,or' theilike-a. The anchoring material-is generallypf the same'materi'al as'the foundationexcept thatitisclissolved in a solventfsumclentato makeit asticky coating.

. Jed toremove' the volatile solvents and, in case rubber is used a vulcanizingtreatmentis .em-

' p ay -F .Imltationsuede of. the Isort: I described above,

whichnis'used' -in shos a ients, handbags, etc., v has certain fundamental 'difilculties. among which are a tendency for the fiock towear off in use, sensitiveness to solvents, ;and especially in the caseof' white and light'colors, easy soiling and difliculty in cleaning. a

According toi the-present invention it hasbeen discovered that. a highlyimproved fabric (using theword'ffabric in its broad sense without lim After-"applying'thegpchthegoodsarethen heatknown-as souping. 40

and. partially saturate the flock. layer. to produce a definite bonding of the fibers, improving its resistance to abrasive wear, tolimparta considers able degree of soil resistance and render. thematerial cleanable with soap and-water, cleaningfluids, or shoe cleaning preparations. a

The previously known flock finished fabric has a loose, highly absorbent surface layer of flock. As a result of the nature of this layer the fabric tends to pick up a great deal of dirt andretain" the same. The coating according to the present invention serves to saturate the flock layer at least partially with the lacquer or enamel where- .by the flock is rendered relatively non-absorbent.

Because of the valuable properties of resistance r to soiling and wearing and the ease with which the fabric is cleaned, the present invention is particularly useful in the caseof white goods where the product resembles buckskin leather and can be used as a substitute for the same in the manufacture of shoes, handbags, etc.

Another objection to the flock finished fabric of the prior art is that by reason of its absorbent character it cannot be given some of the modern ornamental finishes which are desirable in this class of artificial fabric. An outstanding example of a process which is unavailable is what is In this process a colored composition is applied to an embossed fabricand then the fabric and composition, while still'wet,

are subjected to a scraping which removes the color from the high spots of the'embossed fabric.

The color then remains only in the depressions or valleys of the fabric and the contrast between, the valleys and the high portions creates the."- ornamental effect. Obviously where a highly absorbent surface layeris present, such as: in the flock finished fabric of the prior art, i,t is

possible to obtain this effect because -the color composition is absorbed rapidly and uniformly by theentire surface layer and scraping will not remove the color from the flock fibers into which it is absorbed. The present invention, however, provides a flock finish in which the flock fibers are coated so as to reduce their absorbency. This coated fabric can then be embossed and when a colored composition is applied to its surface it will not be absorbed into the flock fibers and the fabric can therefore be scraped in accordance with the usual souping operation.

In accordance with the invention, the flock finished fabric is coated with an enamel having a base of suitable plastic or resin material such as ethyl cellulose, cellulose acetate, Vinylite" resin or other natural or synthetic plastics or resins. The enamel preferably contains a slip agent and a suitable pigment. Particularly useful as a slip agent is talc, and a particularly good white pigment is titanium dioxide. It will be understood, however, that other and different slip agents and pigments can be used in carrying out the invention. For example, instead of talc, mica, zinc stearate, aluminum stearate and other metallic stearates can be used in whole or in part, or they can be mixed with one another. As a pigment instead of titanium dioxide other white pigments such as zinc sulphite and lithopones can be substituted in whole or in part or pigments of other colors can be used to obtain different color effects.

- A particular function of the slip agent is to improve not only the feel of the fabric but also to prevent marking of the material by rubbing against other substances. As an example, a nickel coin (five-cent piece) rubbed edgewise upon an uncoated white flock finished fabric will leave a gray to black mark, whereas when the fabric is coated according to the present invention no mark is left when the coin is rubbed against it in the same way. This is one indication of the superior non-soiling properties of the fabric produced according to the present invention.

The binder or base, slip agent and pigment are incorporated into a solvent suitable for the binder employed. Such solvents are well known and a wide choice is available for the different binders. In addition to the aforesaid ingredients, the coating composition can contain plasticizers for the binder, for example, butyl phthalate, butyl glycollate, or other plasticizers well known in the art.

The invention is not restricted to white fabrics but can also be applied to fabrics of various colors. Colored pigments can be used in place of the white ones in the enamel or it can be colored partly or wholly with a suitable dye or other coloring agent. The color desired will of course determine the selection of the pigment or dye. On the other hand, a clear coating composition prepared without the use of any pigment can be used although the slip agent should be present to produce the soil resistance and improved feel above described.

In practice it is preferable to apply the coating to the surface of the fabric by means of a doctor knife in one or more coats on a finishing machine, but any other convenient method, such as application by a coating roller or by spraying, can be substituted. The fabric is then passed through a drying tunnel or the like to evaporate the solvent from the coating, after which it is preferably finished, as by sanding and brushing,

to remove the surface harshness imparted by the coating.

If a vulcanizabl foundation is used, the coating according to the invention can be applied to the fabric before or after vulcanizing the foundation but preferably for convenience the coating is generally applied after vulcanization.

An embossed imitation suede leather of the type described can be made by impressing a grain pattern on the fabric by any appropriate means. It is Preferable first to apply the enamel coating and afterwards to emboss the desired grain pattern. However, it will be understood that the coating can be applied after the fabric is embossed, if desired, by spraying or other coating methods adapted for use on irregular surfaces. Where the foundation material is rubber, the embossing will preferably take place before vulcanization because embossing is more difficult after vulcanization. Where a rubber foundation fabric is to be embossed it is preferred to perform the coating before vulcanization while the fabric is still smooth. If vulcanizable, the fabric is then vulcanized in the usual way, preferably by dry-heating in a festooning oven.

A fabric either smooth or embossed produced according to the invention can be given a surface ornamentation by printing a desired pettem from engraved rolls. Another type of ornamentation is the souping" previously described. The souping is done only after embossing since there must be a difference in the levels of portions of the surface.

The following are examples of specific coating compositions which can be used in carrying out the invention.

Example 1 Per cent by weight Ethyl cellulose 3.25 Titanium dioxide 4.56

- Talc 13.7

Ethyl acetate 24.59 Ethyl alcohol 29.79 Petroleum naphtha 24.11

Example 2 This example shows a coating composition in which a vinyl resin is used as the binder.

Per cent by weight Vinylite resin 5.13 Title 12.51 Titanium dioxide 4.21 Methyl ethyl ketone -l 78.15

This composition has a total of 16.72% filler (pigment plus slip agent) which is 3.25 times the percentage of base (Vinylite resin).

Vinylite is a copolymer of vinyl acetate and vinyl chloride produced by Carbide and Carbon Chemicals Company.

Example 3 .The present example shows a white coating composition in which cellulose acetate is used as the binder.

Per cent by weight Cellulose acetate 4.13

Talc 14.15 Titanium dioxide 4.82

Acetone 37.55 Methyl alcohol 30.83 Ethyl acetate 8.52

In this composition the filler constitutes 18.97% of all the ingredients and is 4.59 times the percentage of the base (cellulose acetate).

Example 4 A blue colored enamel containing no slip agent can be made up as follows:

Per cent by weight Ethyl cellulose 3.58 Ultramarine blue 10.04 Ethyl acetate 27.08 Ethyl alcohol 32.75 Petroleum naphtha 26.55

In this composition the filler (pigment) is 10.04% which is 2.8 times the amount of base (ethyl cellulose).

It will be understood that these examples are merely indicative of the variations which can be made in the coating composition and the invention is not limited thereto. The proportion of solvent to solid matter, for instance, can be varied Within wide limits to suit the method of application as well as to determine the effect desired. It will be obvious to those sln'lled in this art that numerous other solvents are available for the binders set out in the above examples. The coloring agent in Example 4 can be replaced by other suitable coloring agents to produce difierent colored compositions.

The bases or binders of the examples can be replaced by other plastics or resins and solvents suitable to the particular ones selected will then be employed.

Example 5 As a specific example of the production of a fabric according to the present invention there may be cited the following:

A piece of bleached 59-inch 2.25 Drill is coated by calendering with 16.4 oz. per linear yard of the following compound:

Pounds Ounces Per cent Milled ale crepe rubber 40. Rotax refined grade I m captobenzothiazole)- 0. 90625 Zinc oxide 5. Titanium dioxide" 12. Dixie clay (aluminum silicate) 12. Magnesium carbonate 5. Paris whiting 65 11% 21. 90625 Laurex (zinc salt of lauric acid)--. 3 i. Reogen (a mixture of sulphonated etroleum 15 parts. n-butyl alco- 01 5 parts. and mineral oil 8 parts) 1 8 0.5 Heliozonc (high melting solid parafi'ine) 2 4 0. 75 Blue pigment 2% dissolved in crepe I rubber 98% 3 0.0625 Rctarder W (salicylic acid and a dispersing agent) l2 0. 2n Zimate (oxidized zinc salt of dimcthyldithio-carbaznic acid) 0 (l. 120 Sulfur 1 8 0. 5-

A on each linear yard of material.

Next, a coating of rubber cement dissolved in a mixture of hydrocarbon solvents is spread onto the surface of the calendered coat. About 14.0 ounces of cement containing 14% solids is applied This cement is made by dissolving the following composition in a mixture of 60 pa ts gasoline and 40 'parts toluene by volume:

Cement composition Pounds Ounces Per cent Milled pale crepe rubber 165 55. I Rotax 3 12 l. Zmc oxide 15 5. Titanium (llOXldO T5 25 Lithoponc 22 i l T. 562:) Laurex. 2 4 0. Heliozone l 8 (i. 5 Petrolatum 3 l. Light mineral oil 9 3. Blue pigment 2% dissolved in crepe rubber 98% 3 0. 0625 9 0. 1875 1 0. 6875 While the surface of the cement coating is still liquid and While the cloth is in motion through the coating machine, an excess of bleached white cotton flocks is sifted upon the wet surface. During the application of the flock to the cloth the latter is agitated by the action of vibrating cords beating against its under side as it passes through the chamber which houses the sieves. About 3.4 ozs. offlock are consumed per linear yard of fabric being processed.

After application of the flock the goods passes over a steam chest where the greater part of the solvent is evaporated. It is then rolled up and run into a heating chamber where it is hung in festoons for vulcanizing. vulcanization is accomplished by application of heat, the goods remaining in the oven for one hour at 260 F. after being brought to that temperature in 1 hours.

At the end of the vulycanization period the suede is brushed by a series of rotating bristle brushes to remove loose or excess flock, after which it is ready for application of the protective enamel coating.

The flock coated fabric prepared as described above is then coated with 8 ozs. per linear yard of the enamel having the formula of Example 1. The enamel is applied under a doctor knife on a coating machine. The coating after drying leaves approximately 1.7 ozs. of solids per linear yard.

The goods, after coating, is pased through a drying tunnel to remove solvent and is thereafter sanded and brushed to remove the surface harshness left by the coating enamel.

The fabric so produced is white and can be used in place of white buckskin leather or the like. It has excellent wearing qualities, is soilresistant and can be readily'cleaned when necessary with soap and water, cleaning fluids or shoe cleaning preparations.

Example 6 In preparing a fabric whichis ornamented by souping, the following procedure can be followed:

A piece of Drill coated as in Example 5 with flock is given a coating of white protective lacquer of the formula of Example 1 before vulcanization. The coated fabric is then sanded and brushed to remove surface harshness. Thereafter, and still before vulcanization, the fabric is embossed in any desired pattern by means of an embossing press or by passing between embossing rolls. The

coated and embossed goods is then vulcanized in a festooning chamber as in Example 5.

After vulcanizing, the soup coat of contrasting color is applied. In this operation an enamel containing a relatively high proportion of pigment of which a specific example is shown below is applied to the surface of the embossed fabric. While the enamel is still wet the fabric is passed under a doctor knife which scrapes the colored from /2 to 3 ounces of solids per square yard of fabric.

In the coating compositions hereinbefore described a lacquer or enamel is prepared consisting of a base, such as a lacquer base, and a filler which may be a pigment or a slip agent and in the preferred form both a pigment and a slip agent constitute the filler.

Where the fabric is to be used in imitation of soft materials like suede or buckskin it is generally desirable to sand or otherwise abrade the coated flock to break down the harshness imparted by the enamel. This abrasive treatment should be controlled so as to produce the softenlng desired but should be stopped before injury can be done to the flock or the fabric. Only a minor amount of the coating composition is removed by this abrasion, the major part remaining upon and in the flock particles where it produces the above-describedadvantages.

the coating lacquers or enamels as well as: in the nature of the flock coated fabric arepossible-with l. The method for improving there sistanceftd wear and soiling of a suede-like flock finished fabric which comprises the steps of applying to the flock finished surface of the fabric an enamel having a base selected from the group consisting of ethyl cellulose, cellulose acetate, and copolymer of vinyl acetate and vinyl chloride, solvent for said base, and filler consisting of at least one of Numerous modifications in the composition' ofii the class of pigments and slip agents, said filler being present in said enamel in the proportion of at least 2.8 times the weight of said base, said enamel being applied in an amount to deposit from about /2 to about 3 ounces of solids per square yard of fabric whereby to penetrate and at least partially saturate the flock but not to form a continuous coating and destroy the flock finished character of the surface, drying said enamel from the high spots of the embossing patenamel on the flock, and abrading the enameled tern, leaving it untouched in the valleys. The flock to remove the; surface harshness imparted weight of coating applied in the souping operation by the enamel and to restore a soft suede-like feel will vary greatly according to the character of the to the fabric. grain and the effect desired, but in general will 2. A method for improving the resistance to run from 1 to 2 02s. wet or to ozs. dry per wear and soiling of a suede-like flock finished square yard. fabric which comprises the steps of applying to The souping enamel employed in this example the flock finished surface of the fabric an enamel has the following composition: having a base selected from the group consisting of ethyl cellulose, cellulose acetate, and copolymer Welght per cent of vinyl acetate and vinyl chloride, solvent for mtmeenuloee (300 see) said base, a pigment and a slip agent, the total Pigment (Bone Black) amount of said pigment and slip agent being at Ethyl Acetate least 3.25 times the amount of said base, said Ethyl Alcohol "f enamel being applied ingan amount to deposit Petroleum' Naphtha-ue from to 3 ounces of solids per square yard of fabric whereby to penetrate and at least par- 100-0 .tially saturate the flock but not to form a con- It is to be understood that the above examples 'tmuous coating and destroy, the flock fimshed are merely illustrative of the invention and not "character 9f the smjfeeei drymg said enamel on limiting. According to the invention the quane "e ebmdmg the enameled flock to tity of coating lacquer or enamelis regulated so move the surface harshness lmperted by the that the resulting product retains the desirable ggg'gif to restore a 50ft suede'hke feel to the 22:32:; itlddiofti ,ulfiiefii iiitm .2 A m before exmamei At the same time the coating wear and soiling of a wh te suede-like flock finmust be of sufficient quantity to partially'peneished fabric which compnses the steps of 'P 'trate the flock particles in order to render them mg to the flockdfimshed surface of the P an less absorbent and more strongly united. In enamel having a base of the group conslstmg of general it has been found that the coating should ethy! cellulose acetate copolymer be applied in such proportion that it will deposit 40 of vinyl acetate and vinyl chloride, solvent for the enamel being at least 3.25 times the amount of said base, said enamel being applied in an amount to deposit from A to 3 ounces of solids per square yard of fabric whereby to penetrate and at least partially saturate the flock but not to form a continuous coating and destroy the flock flnished character of the surface, drying said enamel on the flock, and abrading the enameled flock to remove the surface harshness imparted by the enamel and to restore a soft suede-like feel to the fabric.

4. A method for improving the resistance to wear and soiling of a white suede-like flock finished fabric comprises the steps of applying to the flock finished surface of the fabric an enamel having a base of the group consisting of ethyl I cellulose, cellulose acetate, and copolymer of vinyl acetate andlvinyl chloride, solvent for said base, titanium dioxide; and talc, the amount of said 'titaniumdibxideplusthe talclbein'g at least 3.25 1 *timesthe amountiof said base, said enamel being applied in-gan; amount; to;deposit from to 3 1 ounces of;solids per'sqliarefyardof fabric whereby t3 penetrate=;and'at;- ;leastpartially saturate the floekibut noti'tdform a. continuous coating and i destroy the ilock'nnishedcharacter of the surface, drying,said enamel-:onthefiochand abrad ing thejlenameled 'flockto'f remove the .surface harshnessimparted by the enamel and a soft suede-likefe'el to the-fabric! to restore l 5. The: method*for' treatingiasuede-likeflock finished fabric-which comprises the steps of'japplying to the flock finishedsurface Qf'the'fabric an enamel having a base selected from the group consisting of ethyl cellulose, cellulose acetate, and copolymer of vinyl acetate and vinyl chloride, solvent for said base, and filler consisting of at least one of the class of pigments and slip agents, said filler being present in said enamel in the proportion of at least 2.8 times the weight of said base, said enamel being applied in an amount to deposit from to 3 ounces of solids per square yard of fabric whereby to penetrate and at least partially saturate the flock but not to form a continuous coating and destroy the flock finished character of the surface, drying said enamel on the flock, abrading the enameled flock to remove the surface harshness imparted by the enamel and to restore a soft suede-like feel to the fabric, embossing saidenameled fabric, applying a colored enamel composition of contrasting color to the flock finished surface of the fabric, and

scraping the fabric while said composition is wet 20 to remove the said composition from the high spots so as to leave the colored composition only in the valleys of the'embossed fabric.

6. A wear-resistant and soiling-resistant enameled suede-like fiock finished fabric produced by the method of claim'l.

7. A wear-resistant and soiling-resistant enameled suede-like flock finished fabric produced by the method of claim 2.

8. A wear-resistant and soiling-resistant enameled suede-like flock finished fabric produced by the method of'claim 3.

9. A wear-resistant and soiling-resistant enameled suede-like flock finished fabric produced by the method of claim 4.

10. A wear-resistant and soiling-resistant enameled suede-like flock finished fabric produced by the method of claim 5.

RUSSELL- GRANT SMITH. WILLIS JOHNSON PHYSIOC, JR.