DE1785080A1 - Process for the production of artificial leather - Google Patents

Description

PATENT LAWYERS Dr. D. Thomsen

Dipl.-Chem.

H. Tiedtke

Dipl.-Ing.

G. Buehling

Dipl.-Chem.

Case K-194 (Tr) /HF.SS / T 2800

8000 MUNICH 2 VAL 33

TELE FON 0811/22 68 84

TELEGRAM ADDRESS: THOPATENT MÖNCHEN AUGUST 8, 1968

Toyo Rayon Kabushiki Kaisha Tokyo / Japan '

and

Ki-Telac Co., Ltd. Osaka / Japan

Process for the production of artificial leather

The invention relates to a method for producing an artificial leather which is tough and tear-resistant and has a smooth surface and good grip. ¹

Numerous methods of manufacturing an artificial leather have been proposed so far. It's an artificial leather with a fibrous sheet material as a

109822/1965

Known substrate that comes relatively close to natural leather in terms of structure and grip; an artificial leather of this kind with a smooth surface has heretofore been produced by the following three methods. The expression "fibrous sheet-like material" includes knitted and woven goods from.

(1) It becomes a knitted or woven object between a cover and a fibrous one inlaid with web-like material.

(2) It becomes the surface of a fibrous sheet-like Material cut off or polished to remove surface irregularities.

(3) 'It * becomes the non-woven cloth by hot pressing smoothed.

j

In method (1), however, can take into account the interposition of the knitted or woven cloth or fabric does not result in a continuous density gradient, as is the case with natural leather. It also shows in the obtained artificial leather, anisotropy peculiar to the knitted or woven article, which is a disadvantage against wear and tear as well as shoe manufacturing. The method (2) leads to severe damage to the the fibers forming the fibrous sheet material as well as weakening such physical properties of the obtained Artificial leather, such as toughness. The method (3) enables the leather to be smoothed; however, in order to

109822/1965

To hold down the surface of the fibrous sheet material fluff, it is necessary to hot-press at a temperature make, which is above the softening point of a resin used as a binder. Will that be in binder resin present in the fibrous sheet-like material heated to this temperature, it softens and dissolves and is finally stuck together. This significantly damages the grip of the artificial leather obtained.

'■■ - . ■; ■■. ... i

The prior art method of making an artificial leather containing a fibrous sheet-like material is to add a binder resin to a fibrous sheet-like material, coagulate and dry it, one Undergoes smoothing and then a coating brings up. In this process, the sheet-like material cannot form a uniform mass with the binder resin be connected or integrated so that the two layers are only weakly glued together. In addition, j According to this method, one cannot obtain a structure which has a "continuous density gradient. Thus has the artificial leather obtained does not have a good grip and cannot be processed into shoes.

The object of the invention is to provide a method for production of tough synthetic leather in a series of simple ones Steps to make that smooth surface and one

10.9827 / 19B5

•.

has excellent grip, this method being free from the above-mentioned disadvantages.

Another object of the invention is to provide a. To provide a method for making an improved synthetic leather that has a: continuous density gradient, a synthetic resin is firmly bonded to a substrate as a coating to ensure a good bond between to get these two layers ..>; .. "'

These objects of the invention can be achieved by a method for manufacturing an artificial leather, which has a first step in which a solution or emul-r sion of a high molecular weight polymer onto the surface a fibrous sheet-like material applied and the so treated sheet-like material with a heated smooth surface is brought into contact to hold down fluff on the surface, as well as a second. Step, in the case of the fibrous sheet-like material treated in this way, a binder solution is applied and then with a coating solution made of a synthetic resin with subsequent coagulation tion is covered. In the second step of the process, the synthetic resin solution forming the coating, which is contained in a solvent is dissolved which is the same or compatible with the solvent of the binder solution, the fibrous sheet-like Material is preferably added while the binder solution is not yet substantially coagulated, in which case the binder

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BATH

and the synthetic resin constituting the coating are coagulated at the same time. · _;

To the first step of the method according to the invention belongs to a solution or emulsion of a polymer high molecular weight on the surface of a fibrous sheet-like material is applied (to be understood as-, fluff-holding polymer of high molecular weight), and that the treated web material is in intimate contact with a '■ " heated smooth surface is placed after the solvent or dispersant of the high molecular weight polymer has been dried or while it is still in an undried state, being treated run at a temperature that does not cause degeneration and destruction of the impregnated in the fibrous web material, fluff-holding polymer of high molecular weight.

Smoothing through the heated surface can be carried out ( are after the solvent or dispersant of the high molecular weight polymer containing fluff is dried off has been; however, it can have a greater effect in holding down the fluff, if it is in one State in which the solvent or the Dispersant remains. The high molecular weight polymer holding the fluff is not a thermoplastic Polymeres * so there may not be sufficient effect in holding down

10982? / 1965

-Bring fiFlaums when it has dried out.

In the conventional production of artificial leather with a fibrous sheet material as the substrate is on the Surface of the fibrous sheet material a surface cover ' layer or coating layer formed by pinholing one by a card, a Garnettöffner or a layered or non-layered web making machine for tangled web material produced fibrous web or by fulling "or a similar measure without punching. At this point, bring fluff onto this fibrous sheet material Difficulty covering the Material to achieve a smooth surface, so that it is impossible to produce a product with a smooth surface obtained, whereby the quality of the product is deteriorated ... '

These disadvantages exist, albeit to a varying degree, in a fibrous web material which does not contain a binder, a fibrous web material obtained by piercing a fibrous web material obtained by needling a web onto a desired thickness was obtained.

To overcome these disadvantages, attempts have been made to form a surface film by embedding or "a higher concentration binder" into the fibrous web material To cause fluff burning or buffing. These ways of working

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BATH ORIGINAL

make the process more difficult, increase production costs and make it difficult to use a thin, foldable synthetic leather. to obtain, wherein the product obtained becomes rubbery. They suffer damage, such as the loss of beauty of one Product due to occurrence of acute-angled kinks, slight occurrence of stripping or tearing between "the layers, Deterioration in drapability and moisture permeability or. Recurrence of fluff due to an intricate Treatment, such as the manufacture of artificial leather. Accordingly, such procedures are not for the fluff hold Recommend measures for the substrate for an artificial leather.

A method has already been proposed in which a fibrous sheet material with a heated roller is brought into contact with the fluff on the surface to melt and in this way the needle punching made of a thermoplastic synthetic resin to hold down fibrous sheet material obtained fluff. This process does not like when making a carpet Bring problem, however, it is not expedient in the case of one Artificial leather substrate. The surface layer of this fibrous web material is filled with fused fibers. this not only worsens the air permeability, the moisture permeability and the foldability of the substrate but ■ also affects the binder and the fibers on the surface layer, so that the strength of the substrate is reduced, will. __

1098 ?? / 1965. ^ ^ '

The aim of the first step of the method according to the invention it is, a smooth, fibrous .bahn material free of "to preserve these disadvantages.

That used in the practice of the invention fibrous web material consists essentially of fibers. Usable fibers are natural fibers, regenerated b fibers, synthetic fibers or mixtures thereof; it is however, it is necessary to select those fibers which are in the solvent for the resin and in a coagulating liquid are insoluble to the resin and do not suffer any deterioration in strength. Such fibers should preferably have a dimension of 0.5-10 denier and a length of 10 mm to 100 mm.

About the process for preparing fibers too a web includes a wet method such as a papermaking method and a dry method such as a Method in which one with the help of a card or a web production machine for random web material (random webber) and a binder resin is added to this web, or a process in which a web is subjected to physical treatment, e.g. is subjected to a chain stitch needle treatment. The latter drying method is used in the invention. To keep a predetermined thickness as leather and the To improve the adhesion of a fibrous web material in the direction of its thickness, a method is preferably used in detail.

109827/1965 "bad original

applies, in which the fibrous sheet material to form a felt needle-punched. The sheet or flat material obtained in this way should preferably have a weight per area

2 2

unit from 150 g / m to 1000 g / m. Kind 'and The number of a needle to be used varies according to the fibers; however, needles number 32-42 used (standard size from Torrington Co., USA). The number

the needle penetrations per square centimeter and the needle penetration |

Penetration depth will be according to the type of fibers and the The number of a needle used is regulated.

To hold down the fluff can in terms of Smoothing the surface in the first step of the invention onto the surface of a fibrous web material as a polymer with high molecular weight e.g. natural rubber, synthetic Rubber, such as acrylonitrile / butadiene copolymers, synthetic Polymers like. Poly (acrylic ester), poly (vinyl chloride) and polyvinyl alcohol), natural high polymers such as starch and casein and cellulose derivatives such as carboxymethyl cellulose are used will. They can be used either as a solution or as an emulsion will. These high molecular weight polymers can be thermoset, but are preferably thermoplastic. A solution or emulsion is applied to a fibrous web material this high molecular weight polymer, brought on »- 'and for example by means of a spray application machine, gravure printing? · application machine and by a knife application machine. One the preferred measure is the one in which it is possible

109822/1965 ^^ - «« ^ -

just apply it on top of the surface.

This high molecular weight fluff-retaining polymer is made according to the fibers that make up the sheet-like Form material, one embedded in the web material Binder and a solvent chosen for the binder. Looking at the adhesion between a surface film and ^ a fibrous sheet or flat material and also the depth of penetration of the surface film into the sheet material, it is preferred that the fluff-holding polymer be of high molecular weight is soluble in a solvent for a high molecular weight polymer which forms the surface film. By choosing such a fluff-retaining polymer, high Molecular weight increases adhesion and integration of the surface film with the sheet material improved.

The amount of the downy po- " The high molecular weight polymer is determined according to the intended use of the fibrous sheet material and the shape of the sheet material forming fibers} but it should be at one Minimum must be kept that can just cause the intended hold down of the fluff.

In the first step of the process of the invention is a fibrous sheet material, the high with an emulsion or solution of the polymer molecular weight has been brought provided _s with a heated surface into contact with the

■ 'BAD OBIQINAL.

109827/1965

- ii - ■

is preferably heated to a temperature that is lower than the glass transition point of the fibers forming the fibrous web material, but not higher than the melting point of the high molecular weight polymer. As heated A hot press or a kiss cylinder roller is used on the surface , however, there is no particular limitation in this regard. If the heating temperature is below the glass transition point of the Fibers of the web material, sufficient hold down of the fluff is not effected. On the other hand, is the temperature above the melting point of the high molecular weight polymer, so the polymer melts on the heated surface, so that when stripping fibers from the surface of the fibrous Material to be torn out. This leads to new fluff and is therefore not desirable.

A fibrous web material preserved from the first writing has a remarkably improved surface smoothness and makes it 'easy to form a surface film, which has a uniform thickness and a smooth surface. In addition, the adhesion between the surface film and the fibrous web material is improved, with the smoothing does not impair foldability or moisture permeability how the air permeability leads.

The fibrous web material treated in this way is then used in Treated a second step in which a binder is applied

1098 2? / 196 6 #P ^0? ^^

and a synthetic one to form a surface layer »Resin solution is applied .. In the second step, the ■ ■ The synthetic resin is preferably applied before the binder solution has essentially "coagulated," wherein the binder and the synthetic resin coating are coagulated at the same time. It is therefore appropriate that the The binder and the synthetic resin coating are the same or have the same chemical composition.

Examples - of preferred binders and synthetic resin coatings thermoplastic resins such as polyamides, poly (vinyl chloride), polyacrylonitrile, synthetic rubber, such as nitrile ^ butadiene copolymers and styrene-butadiene copolymers, and polyurethane. These resins can be mixed in twos or more. she are added to the fibrous web material as a solution in a solvent, in which the fibers are not soluble, which the form fibrous web material. However, it is necessary that the synthetic one used for the formation of a surface layer Harzüberzug'a viscosity which is higher than that of the binder solution. The viscosity of the synthetic ' Resin coating is advantageously in the range from 100 to 10,000 poise and that of the .. binder resin solution in the range from 0.1 to 100 poise. Advantageously, the solvent for the binder is the same as that for or with the synthetic resin coating Solvent compatible. Examples of compatible solvents are dimethylformamide, diethylformamide and dimethylacetamide

10 9 8 2 2/1965

and dimethyl sulfoxide. It is possible in the synthetic Harness solution, depending on the need, a pigment, such as Koh- · ■ carbon black, filler such as precipitated calcium carbonate and to incorporate cellulose powder or a plasticizer. When impregnating a fibrous sheet material with a It is useful to use a squeezing machine as a sieve or ironer to uniformly pour the binder into a binder solution to get the inner layer of the fibrous web material. Then a syn ~ ■ '· ™ is used to form a surface layer synthetic resin applied to a surface that has been subjected to a smoothing treatment in the first step, with the aid of a reverse roll coater or a coater in a manner which essentially no coagulation. of the binder resin.

In the invention, a synthetic resin coating or synthetic coating resin for forming a surface layer is applied before a binder resin is coagulated, and it is used in i

m t.

the interface causes a liquid-liquid weakening. If the binder resin and the synthetic coating resin are then coagulated at the same time, the fibrous sheet material becomes with the. Surface layer united to an extent that they do not differ from each other be separated. A wet process is used to coagulate the binder resin and the synthetic coating resin, which causes a solvent to be drawn off into a liquid, e.g., water, which is in contact with the solvent is compatible as well as a dry process in which the '

10982 2/196 5

'_ ₁₄ - r / 85080

Drawing off the solvent, for example by heating is achieved. The wet process is preferable in terms of grip and moisture permeability of the end product. By washing with water, drying and surface finishing after the coagulation step, one obtains a leather that is very similar to natural leather. The artificial leather obtained can be passed through an embossing machine. A paint such as nitrocellulose varnish can also be used to improve the gloss and color of the surface.

In addition, the synthetic coating resin can be applied axially or several times in succession to form a surface layer in order to gradually change the structure of the surface film. An embodiment of the invention comprises a first step, is brought in which a web or sheet material, a polymer of high molecular weight up \, which is a solvent for a binder resin and

synthetic coating resin insoluble but in a coagulating Liquid or washing liquid. is solvable · »as well as a ■ second step in which the binder resin and the synthetic coating resin is applied, and finally the following Step of coagulation and / or water washing. In this embodiment, the applied to the fibrous web material High molecular weight polymer dissolved and to prevent excessive bonding between the binder and the

109822/1965

Fibers removed to make the final product foldable. .

The synthetic leather obtained according to the invention is free of surface defects due to fluff, as is the case with her- -_ common products and has good smoothness. Also, there is adhesion between the surface resin layer and the fibrous sheet material of the artificial leather obtained, since the binder and the synthetic coating resin coagulate at the same time and inte- f with the sheet material be grouped or united. As part of the resin of the surface layer has penetrated the fibrous sheet material a density gradient of the synthetic coating resin results and surface-to-back binder resin. Therefore

the artificial leather obtained has a structure similar to natural leather, where there is a continuous density gradient from the layer is present on the flesh side to the layer on the hair side, both layers being united or integrated with one another. Furthermore, according to the invention, the artificial leather More resin near the surface of the fibrous web material and the fibers near the surface are free to move prevented. When such an artificial leather is treated in the stretched state, traces of the perforation do not appear on the surface by. This is advantageous when clamping shoes in shoe manufacturing - for example. ,

109827/1965

In the case of the invention, the penetration of a synthetic Coating resin conveyed into a fibrous web material through .. a binder solution. Much synthetic penetrates. · Coating resin into a substrate. In addition, the adhesion between layers is improved, which is both a binder and a synthetic coating resin can be coagulated at the same time.

The following examples serve to illustrate the invention and are not of a limiting nature. All parts and percentages are based on weight, unless otherwise ■ stated. ·.

Example 1 and "Comparative Examples 1 to ¹ \

It is made from polyester staple fibers with a denier of 1.5, a length of. 35mm 'and a curl number of 15 turns per inch using a cross roll of fibrous sheet material having a weight per unit area

■ 2

made of 250 g / m. The fibrous sheet material obtained was punched with a conifer using number 40 needles (standard from Torrington, Co., USA). the The number of needle penetrations per square centimeter was 500 and the needle penetration depth was 8mm. With the help of a spray application machine was on the surface of the perforated sheet material an IQ ^ ige aqueous solution of poly (vinyl alcohol) • with a molecular weight of 1,500 applied until the

10982771965

Uptake of poly (vinyl alcohol) uniformly over the whole

ρ
Surface 5 g / ra. was calculated as the content of pesticides.

The fibrous sheet material was then passed through a pair of hot rollers heated to 160 ° C, so that its thickness after hot pressing was 1.0 mm.

One hundred parts of a copolymer of 35 moles of vinyl acetate and 65 moles of vinyl chloride, 20 parts of carbon black, 50 parts of dioctyl phthalate as a plasticizer and 35 parts of λ calcium carbonate were dissolved in dimethylformamide, and a solution with a solids concentration of 10 $ and a viscosity of 5 poise was obtained and a solution with a solids concentration of $ 30 and a viscosity of 300 poise was prepared. The 10% solution was used as a binder and the 30% solution was used to form a coating. The fibrous web material was immersed in the 10 # binder solution and squeezed by a mangle until the inclusion as "solids content" was 50 parts per 100 parts of the fibers.

Subsequently, with a. Coating machine with a gap distance of 1.5 mm applied the 3Q # solution to the smoothed surface. After impregnation and application, the treated web material was ^{immersed in water at 20 °} C. in order to coagulate both the binder and the synthetic coating resin. Subsequent washing with water and drying resulted in an artificial leather that is tough, has a smooth surface and has a good grip. The physical properties of the leather obtained are shown together with those of the comparative examples or samples (1), (2), (3), and (k) . 109822/1965

The comparative specimens have been 'made according to the following Working methods established.

Pattern (1)

The smoothing and fluffing treatments of the first step of the invention were not carried out. Under the same conditions as in Example w 1 , the same binder and synthetic coating resin as used in Example 1 were applied to a fibrous sheet material and coagulated at the same time.

• Pattern (2)

The same binder as used in Example 1 was applied to a fibrous web material. It was then subjected to coagulation, washing with water k and drying treatment. The fibrous web material treated in this way is hot-pressed at ΙβΟ C using a calender roll. It is coated with the same coating solution as used in Example 1, followed by coagulation, washing with water and drying.

Pattern (3)

The same binder is used on a fibrous web material applied as it was used in Example 1 and it

10982? ./ 196 5 _BAD ORIGINAL

the treated sheet material was tapped from both sides until it was about 1.0 ram thick. Under the same conditions as in example! was applied to the fibrous The same synthetic coating resin as used in Example 1 was applied to sheet material.

template

It is a binder to a fibrous Bahnrnäterial applied and this tapped from both sides to a thickness of about O ₃ S mm. A 0.2 mm thick woven fabric made of 40 count yarns composed of 30 parts of polyester and 70 parts of cotton is placed on the fibrous sheet material using a synthetic resin having the same composition as the synthetic cover shara. A synthetic coating resin is then applied to the woven material under the same conditions as in Example 1.

10-9 8 2? "/ 1 9 65 -

example 1 high Well Well comparative
example 1 middle . Well Well comparative
Example 2 high bad i bad

- 20 -

Table I.

Form error liability

Toughness Foldable, durable, smooth between the layers

none good good many bad good

comparative. . . . ' some

Example 3 low good bad no bad bad

comparing something

Example 4 high bad bad no good bad

Example 2

A prepolymer made from diphenylmethane-4,4'-diisocyanate and polyethylene adipate with a molecular weight of 2,000 was chain-extended by butanediol. The polyester polyurethane obtained was dissolved in dimethylformamide to obtain _s poise to a 15 # solution having a viscosity of 20th A fibrous web material, which was subjected to the first step according to Example 1, was immersed in this solution

and then squeezed by a lack. until the 'inclusion in solids content is 40 parts per 100 parts of the fibers was followed by an immediate smoothing treatment. A solution was applied to the fibrous web material treated in this way a synthetic coating resin applied / This solution tvar. by mixing 100 parts of polyester-polyurethane,.

10 98?.? M 965

BATH ORIGINAL

1/85080

10 parts carbon black ₃ 60 parts calcium carbonate precipitate produced with dimethylformamide. After impregnation and application of the coating the binder solution and the solution of the synthetic resin coating was simultaneously coagulated by immersion in water at 20 ⁰ C. The treated fibrous sheet was then washed with water and dried. It was pressed with a metal roller with an embossed pattern, an artificial leather with a leather-like grain on the surface being obtained. The leather obtained had a smooth surface and good grip, similar to the product according to Example 1.

Example 3

Using a random-ply web manufacturing machine (random webber) was mm nylon-6 staple fibers having a denier of _3} -this length of 51 and a number of crimps of 15 turns per inch, a fibrous sheet material with a "weight per unit area of 400 g / The fibrous sheet material was punched through a conifer. The pins used were number 36 (standard from Torrington Co., USA) The number of pinholes per square centimeter was 400 and the needle penetration depth was 10 minutes on the outermost surface of the treated fibrous sheet material was a 25 # solution of a latex ("Hycar 1571", The Japanese Geon Company.) of an acrylic

1098 27 / 1.96 5

nitrile-butadiene copolymer sprayed until the intake to the

Solution 5 g / m - as solids content - was uniform across the fibrous sheet material, Dc.3 sheet material was below. Using a hot air dryer at 10O ⁰ C dried. The dried product was passed through a pair of calender rolls heated to 150 ° C to bring the thickness of the final product to 1.0 mm.

A polyurethane prepolymer was prepared by reacting ^L 2 moles of polytetrahydrofuran having a molecular weight of 2080 with 3 * 2 moles of a mixture of 2.4 moles of tolylene diisocyanate and 2,6-tolylene diisocyanate. It was reacted with an equal molar amount of hydrazine hydrate in dimethylformamide to form a polyurethane solution. The polyurethane solution was mixed with 40 parts - based on 60 parts of the solids content of polyurethane - of an acrylonitrile-butadiene copolymer composed of 35 moles of acrylonitrile and 65 moles of butadiene; the obtained mixture was diluted with dimethylformamide to form a solution having a solid concentration of 10% and a viscosity of 5 poise. This solution was used as a binder solution using the same synthetic coating resin solution as in Example 1. The fibrous sheet material was treated in the same manner as in Example 2 using these solutions. An artificial leather with a smooth surface and good grip was obtained.

ORK & NAL 9827/1965

example

The needle-punched fibrous used in Example 3. Web material was immersed in a 10% aqueous solution of poly (vinyl alcohol) having a degree of polymerization of 500 and a degree of acetylation of 13 ° C and squeezed through a mangle until the absorption of a pesticide content. Poly (vinyl alcohol) reached $ 10 based on the weight of the fibers. A 25 # solution of a latex of an acrylonitrile-butadiene copolymer was sprayed onto the fibrous web material treated in this way, so that the absorption of the mixed polynating solids content should be about 10 g / m uniformly over the entire surface of the web material. The web material was dried by a hot air dryer at 100 C and passed through a pair of calender rolls heated to ITE C to smooth its surface. The binder solution and the synthetic coating resin solution used in Example 2 were sequentially applied to the fibrous sheet material. Immediately thereafter, the solvent vmrde extracted in water at 20 ⁰ C to cause coagulation. The web material was then washed for 30 minutes in a warm water at 30 ⁰ C with simultaneous extraction of the poly (vinyl alcohol). . It was dried for 20 minutes in a dryer at 10O ⁰ C. An artificial leather with a smooth surface and good grip was obtained.

109877/196 6

Example 5

The needle-punched, fibrous sheet of Example! 'Was given the same plaum hold-down treatment as in Example 1 subjected. The treated web material was immersed in a 2O $ solution of polyurethane used in Example 2, immersed in dimethyl sulfoxide and squeezed through a lack, so that the solid intake 20 parts against- ™ over 100 parts of the Pasern "should be. Immediately afterwards was the matted surface with a 30 # solution of

100 parts of polyurethane, 50 parts of calcium carbonate precipitate ¹ and 30 parts of carbon black in dimethylformamide coated and subjected to in water of 20 ⁰ C to a coagulation step. Subsequent washing with water and drying provided
an artificial leather which had a smooth surface and a good grip similar to the products of Examples 1 to 3 '. ' ^v:

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Claims (12)

Claims ■ 1. A process for the production of artificial leather, characterized by a first step in which a fluff-containing polymer of high molecular weight is applied to the surface of a fibrous web material and the surface of this fibrous web material is brought into contact with a smooth surface which is on a Temperature not lower than the glass transition point of the fibers forming the fibrous web material but not higher than the melting point of the high molecular weight polymer in order to hold down the fluff on the surface of the web material, and by a second step in which the fibrous web material a binder solution and then a solution of a synthetic coating resin .applied and these then 'are coagulated. ; 2. The method according to claim 1, characterized in that that the coagulation in the second step - with the help of a liquid is carried out, which is compatible with the solvents of the binder and; the synthetic coating resin and which do not solvent for the binder and the synthetic coating resin is. 3. The method according to claim 1 or 2, characterized in that the solution of the synthetic coating resin is applied before the binder solution "in the second step 10 9827M96 5: essential is coagulated ^{un (i} ß ^{as the} binder and the syn "thetic coating resin will simultaneously coagulated: -. 4. The method according to claim 1 to 3, characterized in that the solvent of the binder is the same as is that of the synthetic coating resin. ψ 5. The method according to claim 1 to 4, characterized in that the solvent of the — binder is compatible with that of the synthetic coating resin. ' 6. The method according to claim 1 to 5 _3, characterized in that the high molecular weight polymer holding down the fluff at least one polymer from a group of natural rubber, synthetic rubber, poly (acrylic acid ester), poly (vinyl chloride), poly (vinyl alcohol), starch, casein and is carboxymethyl cellulose. 7. "The method according to claim 1 to 6, characterized ^ that after the coagulation, washing with water takes place, whereby the down-holding polymer applied in the first stage high molecular weight is dissolved. 8. The method according to claim 1 to 7 , characterized in that the binder is at least one binder from the group consisting of polyamide, PolyC inylchlorid), polyacrylonitrile, an acrylonitrile-butadiene copolymer, a styrene-butadiene mixed polymer 109822/1965 BATH ORIGINAL -'27 - meres and polyurethane is. . . . . 9. ■■ The method according to claim 1 to 8, characterized in that ·. ₃ indicates that the synthetic coating resin at least one
Resin from the group of polyamide, poly (vinyl chloride) , polyacrylonitrile, an acrylonitrile-butadiene mixed polymer
Styrene-butadiene copolymer and polyurethane. 10. The method according to claim 1 to 9 _3, characterized in that the viscosity of the solution of the coating resin
is greater than that of the 3inder solution, 11. The method according to claim 1 to 10, characterized in that that the high molecular weight fluff-holding polymer is in the form of a solution. 12. The method according to claim 1 to 10, characterized in that that the fluff-holding polymer is high molecular weight is in the form of an emulsion. 109827/1965