DE2401163A1 - POLYURETHANE BASED TEXTILE ADHESIVE - Google Patents

Description

PATENT LAWYERS

OR. I. MAAS

DR. G. SPOTT

8000 MONKS 40

SCHLEISSHEIMERSTR. 299

TEU 3592201/205

American Cyanamid Company, Wayne, New Jersey, V.St.A.

Textile adhesive based on polyurethane

The invention relates to aqueous polyurethane adhesives for lamination and flocculation of textile materials.

Lamination is the binding of fabrics, and synthetic or natural fabrics, either to one another or to another plastic material, which makes one a multi-layered product. Flakes are the binding of short staple fibers in a vertical position on a substrate understood, and thereby a fluff-like material is obtained.

As mentioned above, lamination is understood to mean in the textile sector tying a fabric on the same or different fabric or fabrics or tying one or more fabrics on plastics materials, including films, sheets and foams.

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A discussion of the fundamentals in the field of adhesives is given in U.S. Patent 3,640,924.

Adhesive preparations in the textile sector are both as flaky as well as laminating adhesives are used. The present invention has predominant application in flaking, but other uses include binding for making laminates.

The adhesives used in laminating and flaking textiles should result in products that (1) when washed, Dry cleaning and pressing are dimensionally stable, (2) result in a permanent bond between the components during washing, dry cleaning and pressing and (3) above satisfactory Have handling and draping characteristics. In the clothing sector, dry cleaning and / or laundering resistance is particularly important however, it is important that the flocked garment is soft to the touch. The adhesive preparation must be about it In addition, apply conventional methods of applying adhesive to fabric or plastic materials like with a doctor blade or a full or engraved transfer roller. Isn a penetration into the tissue or to avoid the foam, the adhesive should be sufficiently viscous. He should even be fully hardened Be flexible in your state and not become brittle as you age. Many of the adhesives currently in use have one Solvent based. However, it is preferable to use water-based adhesives, as these (1) are thinned with water for cleaning (2) pose no fire or explosion hazard, (3) have little smell and are non-toxic and (4) do not pollute the air.

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2401183

In U.S. Patent 3,640,924 there is generally a method of manufacture a textile adhesive preparation described after which a prepolymer with terminal isocyanate groups in a latex is converted by converting it into an aqueous Stirring medium from a tert-lower alkylamine, the. themselves running chain extension with water until practically all isocyanate groups have reacted, and the A thickener was added to the obtained latex so as to adjust its viscosity to 20,000 to 100,000 cps. These The preparation is generally suitable for the flocking process, but it cannot be used to make flaked ones Fabric, as the corresponding products feel like a board.

An aqueous adhesive preparation has now been found which is very suitable as a textile flock adhesive for clothes, because the flocked material obtained is soft to the touch and additionally has the required durability when washing and dry cleaning. The adhesive preparation is suitable also as a bonding adhesive for nonwoven fabrics, and it can be used as a textile finishing agent, such as for Modify by hand to improve wrinkle recovery or to increase the tear strength and tensile strength of woven or knitted fabrics.

The adhesive preparations according to the invention are aqueous dispersions of a special class of self-dispersing agents or emulsifying polyurethane polymers that are a plasticizer contain. The aqueous dispersions are obtained by adding a certain class of polyurethane prepolymers with terminal isocyanate groups and free carboxyl groups to water that contains a tertiary aliphatic amine, whereupon the whole thing can be chain-extended with water until all isocyanate groups have reacted.

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The polyurethane latex obtained in this way is adjusted to the desired viscosity with suitable thickeners thickened.

The polyurethane prepolymer provided with terminal isocyanate groups with free carboxyl groups is prepared by reacting an organic diisocyanate with a slightly submolecular amount of three types of glycol.

The first type of glycol is a non-polymeric glycol / that has a pendant carboxyl group. The second type of glycol represents is a common non-polymeric polyol and the third type of glycol is a conventional polyether glycol. Mixtures can also be used such glycols can be used.

The organic diisocyanate is an aromatic diisocyanate whose isocyanate groups are directly attached to the aromatic Are ring bonded, such as tolylene diisocyanate or mixtures thereof. The diisocyanates can have other groups as substituents but compounds without such groups are preferred.

The non-polymeric glycol on which there is a carboxyl group has the following formula I

HO-CH ₂ -C-CH ₂ -OH I,

COOH

wherein R is hydrogen or lower alkyl having 1 to 3 carbon atoms. Glycols of the formula I are 2,2-bis (hydroxymethyl) lower alkanoic acids, and belong to them

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2,2-bis (hydroxymethyl) acetic acid, 2,2-bis (hydroxymethyl) propionic acid, 2,2-bis (hydroxymethyl) butyric acid or 2,2-bis (hydroxymethyl) valeric acid. The preferred glycol is 2,2-bis (hydroxymethyl.) Propionic acid.

The non-polymeric polyol has the following formula II

HO-CH ₀ -C-CH ₀ -OH "II, R ¹

where R is hydrogen or lower alkyl having 1 to 3 carbon atoms and R ^{1 is} hydrogen, lower alkyl or hydroxyalkyl. Glycols of the formula II are 2-hydroxymethyl-1,3-propanediol, 2-methyl-2-hydroxymethyl-1,3-propanediol, 2-ethyl-2-hydroxymethyl-1,3-propanediol and the like.

The polyalkylene ether glycol has the following formula III

H (-0-CH-CH ₀ ) -OH III,

,. Δ q

^R 1

where R is lower alkyl and q is an integer which is sufficiently large that the average molecular weight for the glycol is from 750 to 5,000, with a preferred average molecular weight of about 1700 to about 2400. Typical glycols are polyethylene ether glycol, Poly-1,2-propylene ether glycol, poly-1,2-butylene ether glycol and the like.

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At least 0.5 moles and up to about 3.0 moles (preferably between 1.0 and 1.5 moles) of the diisocyanate per mole of total amount of glycol should be used to prepare the prepolymer. The molar ratio of the non-polymeric glycol containing a carboxyl group to the non-polymeric polyol and the polyalkylene ether glycol should be between about 0.5: 0.1: 0.5 to 2.0: 1.0: 2.0, and preferably about 0.5 , 75: 0.1: 0.7J to 1.25: 0.5: 1.25. The ümsetzungstemperatur to prepare the prepolymer should be between about 5O ⁰ C and 100 C, and preferably about 75 to 9O ⁰ C amount.

The plasticizer can be added together with the glycols at the beginning of the reaction, or it can also be added as Add externally emulsified additive after the chain extension of the prepolymer has ended. The .initial encore the plasticizer is preferred as this simplifies the process and also facilitates emulsification, by increasing the fluidity of the prepolymer phase obtained.

Plasticizers suitable according to the invention are polyesters, but phthalate esters, phosphate esters and use long chain aliphatic esters.

The amount of plasticizer added should be between 5% and 50%, preferably between 15 and 25%, and based on the weight of the prepolymer.

The amount of water used together with the prepolymer to form the water extended polyurethane latex is not critical. It can be latices with solids contents between Make about 10 and up to about 60%, but a solids content of 25 to 50% is preferred. The formation of the latex Room temperature is simple and practical, but you can also work at higher or lower temperatures.

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The tertiary amine present in the water during latex formation is a tertiary lower alkylamine, such as trimethylamine, Triethylamine or tripropylamine, triethylamine being preferred will. The amount of tertiary amine used should be between 2 and 10%, preferably between 3 and 7%, and based on the weight of the prepolymer. Generally the preferred amount of tertiary amine is about 0.65 equivalent for each carboxyl group present in the prepolymer.

The adhesive preparation can be used during the production of the Polyurethanprepöylmers or after chain extension of the prepolymer can also be mixed with other agents. For some Types of application can include the addition of an antioxidant such as 2,2 * -Methylene-bis- (4-methyl-6-t-butylphenol) or the like, or an ultraviolet absorber such as 5-chloro-2 * - (3,5-di-t-butyl-2-hydroxyphenyl) -benzotriazole and the like, be appropriate. Other types of application may have the addition of a make thermosetting arainoplast precondensate desirable, such as a melamine-formaldehyde-urea or urea-formaldehyde condensate so as to improve the solvent resistance of the adhesive. The preferred atinoplast precondensates are melamine-formaldehyde condensates, including inclusion their alkyl ethers. The addition of the monoisocyanate, such as Phenyl isocyanate, is beneficial for reducing yellowing of the finished product.

Small amounts of processing aids, such as foam retardants Agents, or preservatives, such as bactericides, can can also be added to the adhesive preparation.

Adequate viscosity of the adhesive is important to prevent excessive penetration of the adhesive into the substrate, on which it is attached. With others

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Should hear most of the adhesive on the surface of the substrate so that there is good adhesion between the flakes and the substrate. Normally viscosities between 500 and 150,000 cps are used.

For further details, reference is made to the already cited literature on adhesive technology.

The invention is illustrated in more detail by means of the following examples.

example 1

Components of the prepolymer: 20OO MG PPG, 4.0% DMPA, 0.82 \ TMP, 20% plasticizer NC0 / OH = 1.3.

A mixture of 270.0 parts of polypropylene glycol with a molecular weight of 2000, 92.0 parts of Paraplex * 'G-30 (a polyester type plasticizer from Rohm and Haas), 18.0 parts of 2,2-bis (hydroxymethyl) propionic acid, 3 , 75 parts of 2-Ethy1-2-hydroxymethyl-1,3-propanediol, 1.75 parts of 5-chloro-2- (3,5-di-t-buty1-2-hydroxyphenyl) benzotriazole and 0.9 parts of 2, 2'-methylene-bis- (4-iiiethyl-6-t-butylphenol) is stirred and heated to 80 to 85 ⁰ C. The reaction mixture thus obtained was slowly added with 67.5 parts ToIylendiisocyanat and then the mixture was stirred 4 to 5 hours at 80 to 85 ⁰ C. Then, 200 parts of the prepolymer O emulsified by this to a mixture of 3.88 parts of Triethylamine and 230 parts of cold water are added, which is then chain-extended by stirring for about 15 hours at room temperature, whereupon the whole is filtered through a sieve with 0.175 mm clear mesh size (100 mesh) and so a latex with a solids content of about 49.6 % receives.

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270.0 parts of the chain-extended polymer latex are used with 0.790 parts of concentrated ammonium hydroxide and a dispersion of 9.15 parts of Acrysol ASE-60 <a commercially available available thickener based on polyacrylics from Rohm and Haas) in 54 parts of water, and the mixture is stirred until it is completely emulsified. By addition of water, the viscosity of the emulsified adhesive is adjusted to about 48,000 cps and the solids content to about 40%.

Example 2

This example shows a flocking process using the adhesive of Example 1

The adhesive preparation obtained according to Example 1 is with. was applied to cotton twill using a doctor blade in the form of a 254 µm (10 mil) thick wet adhesive. The wet adhesive is pelted with rayon flakes 1.0 mm in length within 15 to 30 seconds, and the flakes are then oriented with a tap bar. The flocked fabric is ^{dried at 152 to 154 °} C. for 5 minutes, and the loose flakes are removed by blowing on a stream of air. The flakes are tightly bound to the structure and have a soft texture. The fabric obtained in this way is examined using a Taber Abraser with CS-10 rollers at a load of 500 g.

After 500 wet cycles and drum drying, the appearance can be reduced of the flocked fabric as good.

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Example 3

This example shows a method in which the plasticizer is added after chain extension, and a comparison is made with a sample without plasticizer. The components of the prepolymer are: 2000 MG PPG, 6% DMPA, 1% TMP, NCO / OH -1.3 / 1 .

475 parts of polypropylene glycol with a molecular weight of 2000 are slowly and uniformly mixed with 37.8 parts of 2,2-bis (hydroxymethyl) propionic acid, 6.3 parts of 2-ethyl-2-hydroxymethyl-1,3-propanediol, 1.55 parts of 2 , 2'-methylenebis (4-methyl-6-t-butylphenol) and 3.15 parts of 5-chloro-2- (3,5-dit-butyl-2-hydroxyphenyl) benzotriazole are added, and the mixture is stirred and heated to 75 ^{° C. under nitrogen.} 119 parts of tolylene diisocyanate (80/20 mixture of 2,4 and 2,6 isomer) are then slowly and uniformly added, and the mixture is stirred for about 4 hours at 80 to 85 ^° C. The free NCO content of the prepolymer is about 2.0%.

600 parts of the prepolymer so produced are added to a stirred mixture of 970 parts of cold water, 140 parts ice and 23.5 parts of triethylamine, and the resulting mixture is stirred at 5 - 10 ⁰ C until volkommenen emulsification. When the emulsification is complete, the mixture is stirred at 20-30 ° C. for about 18 hours to extend the chain. The latex so produced contains about 34% solids.

A. 232 parts of the chain-extended polyurethane polymer emulsion are mixed with 37.5 parts of a second emulsion which is prepared by adding 180 parts of water, 12 parts of Triton ^iR * X-100, 220 parts of Paraplex * ^R) G-30 and 8 parts of Triton ^ X-45 stirred at high speed and then with 1.4 parts of ammonium hydroxide and a dispersion of 16.4 parts

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Acrysol * ^R 'ASE-6O was added in 58.5 parts of water. After about 24 sfcündigera stirring at about 20 to 3O ⁰ C, the adhesive composition has a viscosity of about 46 cps 0oo and contains about 30% solids.

B. 26O parts of the extended chain polyurethane polymer
1.2 parts of ammonium hydroxide and a dispersion of 13.2 parts of Acrysol ¹ 'ASE-6O in 35 parts of water are added. After about 24 hours of stirring at 20 ⁰ C to 30 ⁰ C, the adhesive preparation has a Viskostität of about 53 000 cps. The viscosity is increased to 40,000 cps by adding water. set.

Example 4

This example shows that a softer feel is obtained when the adhesive used for flaking contains a plasticizer, as opposed to an unplasticized adhesive. It also shows that the plasticizer can be added to the adhesive after the chain has been extended.

The flocking procedure of Example 2 is carried out using the Repeat adhesive preparations of Examples 3A and 3B. A Comparison of the handle of the flocked fabric shows that with Fabric flocked with the adhesive of Example 3A is much softer to the touch than that flocked with the adhesive of Example 3B Material.

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example

This example shows the production of an adhesive that falls under the prior art known from US Pat. No. 3,640,924. The prepolymer of this adhesive contains neither trimethylolpropane (CTMP) nor plasticizer, and its NCO / OH (2/1) content is higher than that of the prepolymer according to the invention

347 parts of polypropylene glycol with a molecular weight of 2000, 11.3 parts of 2,2-bis (hydroxymethyl) propionic acid, 2.2 parts of 5-chloro-2- (3,5-di-t-buty1-2-hydroxyphenyl) benzotriazole and 1.1 parts of 2,2'-methylenebis (4-methyl-6-t-butylphenol) are mixed together and heated to 80 ⁰ C. The resulting mixture is then mixed with 91.0 parts of tolylene diisocyanate and held for 3 hours at 75 to 80 ⁰ C. 200 parts of this prepolymer are emulsified by adding it to a mixture of 3.74 parts of triethylamine and 235 parts of cold water. The mixture is stirred overnight at room temperature and then filtered through a 0.147 mm mesh (100 mesh) screen to give a latex having a solids content of about 46%. The latex is then brought to a viscosity of 51,000 cps by adding

/ TV \

Set of a dispersion of Acrysol ^v 'ASE-60 thickened in water, and the solids content of the latex obtained in this way is 40%.

Example 6

This example shows a flake with a known type of adhesive. It can be seen that the non-plasticized known type Material is less resistant to abrasion than the adhesive according to the invention

The adhesive preparation according to Example 5 is used as the adhesive for flaking, and the method according to Example 2 is used, drying ^{at 135 ° C. for 7 minutes.}

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2 ^ 01163

The flocked fabric (139 g) is then dyed by soaking it for one hour in a dye bath which contains 2.75 g of Calcomine Scarlet B (Color Index No. 22 240) and 27.8 g of sodium chloride in 4170 g of water at 93 ^° C. The colored sample is then rinsed with cold water and dried. The fabric looks very bad. Assessment of the flocked fabric using a Taber Abraser with CS-10 rollers at a load of 500 g shows that the appearance of the fabric is poor after only 150 wet cycles. The flocked fabric is rough to the touch.

Example?

This example shows the importance of the presence of TMP ■ in the polymer

A. The procedure of Example 3 is repeated to prepare the polymer, except that no 2-ethyl-2-hydroxymethyl-1,3-propanediol is added. 200 parts of the prepolymer thus prepared are added to a mixture of 270 parts of cold water, 100 parts of ice and 7.5 parts of triethylamine, and the mixture is stirred for 15 hours at room temperature, whereupon it is passed through a sieve with a 0.147 mm clear mesh size (100 mesh ) is filtered. 225 parts of the latex obtained are mixed with 38.2 parts of another latex, which is prepared by adding 180 parts of water, 12 parts of Triton ^(R) X-100, 220 parts of Paraplex ^(R) G-30 and 8 parts of Triton

(R)
ton X-45 mixed together at high speed and then 1.3 parts of concentrated ammonium hydroxide as well

(Ri, a dispersion of 15.0 parts of Acrysol ^v 'ASE-60 8 parts of water is added in 7O _r, yielding .erhält a viscosity of 49 000 cps.

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Example 8

This example shows that in the absence of TMP the flocked fabric looks bad after drying.

The adhesive preparation according to Example 7 is applied to 8O cotton twill as in Example 2 and dried for 5 minutes at 151 to 154 ⁰ C. The flocked fabric is dyed with Calcomine Scarlet B according to the procedure described in Example 6. The fabric looks bad after drying overnight.

Example 9

This example shows the preparation of an adhesive that contains Q.5% TMP in the prepolymer.

The procedure is exactly the same as in Example 3, but notwithstanding that 3.15 parts of 2-ethyl-2-hydroxymethyl-1,3-propanediol are added. The prepolymer is then chain-extended as described in Example 7, Part A. 225 parts of the latex thus obtained are mixed with 38.1 parts of the second emulsion described in Example 3, Part A, whereupon the whole thing is mixed with 1.0 part of concentrated ammonium hydroxide and a dispersion of 11.8 parts of Acrysol ¹ ASE-60 in 73, 9 parts of water are added, resulting in a final viscosity of 20,000 cps.

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Example 10

This example shows the poor abrasion resistance obtained when using only 0.5% TMP in the prepolymer.

The adhesive obtained according to Example 9 is according to the in

Example plotted procedure described 8O 2 on cotton twill and dried 5 minutes at 151 to 154 ⁰ C. The flocked fabric is dyed according to Example 7. The fabric so dyed looks good, but its appearance is quite poor after 500 wet cycles in a Taber Abraser instrument using a CS-10 roller at a load of 500 g.

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Claims (14)

Patent claims 1. Process for the production of a polyurethane adhesive preparation in the form of an aqueous dispersion, characterized in that one (1) Preparing an isocyanate-terminated prepolymer in the presence of a plasticizer by adding a Tolylene diisocyanate reacts with a mixture of three types of glycols, one of which is a non-polymer Is glycol, which carries one carboxyl group, the second is a non-polymeric polyol and the third is a polyalkylene ether glycol, (2) that of plasticizer and polymer with terminal isocyanate groups existing mixture in an aqueous medium containing a tertiary lower alkylamine, to form a latex until all remaining isocyanate groups have reacted with water, and (3) adjusts the viscosity of the latex thus obtained by adding a thickening agent. 2. The method according to claim 1, characterized in that that the plasticizer is added after all of the isocyanate groups have reacted with water and not during manufacture of the prepolymer. 3. The method according to claim 1, characterized in that the non-polymeric glycol has the formula HO-CH ₂ -C-CH ₂ -OH COOH 409829/1007 where R is hydrogen or lower alkyl with 1 to 3 Carbon atoms. 4. The method according to claim 1, characterized in that the polyalkylene ether glycol has the formula H (-0-CH-CH ₀ ) -OH ^R 1 where R _{1 is} lower alkyl and q is an integer which is so large that the glycols have an average molecular weight of 750 to 5,000, and preferably about 2,000. 5. The method according to claim 1, characterized in that the non-polymeric polyol has the formula HO-CH ₃ -C-CH ₂ -OH CH ₂ OH where R is hydrogen or lower alkyl with 1 to 3 Carbon atoms. 6. The method according to claim 1, characterized in that triethylamine is used as the tertiary amine. 7. The method according to claim 1, characterized in that the molar ratio of the moles of tolylene diisocyanate to the 409829/1007 Moles of total glycol in the prepolymer between 1.0 / 1 and 1.7 / 1. 8. The method according to claim 7, characterized in that the molar ratio of the moles of tolylene diisocyanate to the moles of the total glycol in the prepolymer is between 1.2 / 1 and 1.4 / 1. 9. The method according to claim 1, characterized in that the mole ratios of non-polymeric glycol / polyol / polyalkylene ether glycol 1: 0.1: 1 to 0.3: 1. 10. The method according to claim 1, characterized in that the polymer / plasticizer molar ratio in the prepolymer is between 90/10 and 70/30. 11. The method according to claim 1O, characterized in that the weight ratio of polymer / plasticizer in the prepolymer is between 75/25 and 85/15. 12. The method according to claim 1 and 2, characterized in that a polyester is used as the plasticizer. 13. The method according to claim 1 and 2, characterized in that that the viscosities of the thickened adhesives are between 500 and 150,000 cps. 14. The method according to claim 1 and 2, characterized in that that a polyacrylic acid type polymer is used as a thickening agent. 409829/1007 ^r