EP0090174A1 - Process for the reinforcement of edges and the closure of hems of textile materials - Google Patents

Abstract

The edges and hems of textile sheet materials which are to be used, for example, as conveyor belts or filter cloths are respectively reinforced or closed with improved elasticity, adhesion and hydrolysis resistance by treating the edge or hem with a radiation-curable, ethylenically unsaturated composition and then irradiating with crosslinking-active radiation.

Description

The invention relates to a method for edge hardening and edge sealing of textile fabrics, in particular filter cloths. In addition to many other uses, textile fabrics are used in industry as conveyor belts and filter cloths. For reasons of durability, coarse-titer synthetic fibers made of polypropylene and polyester are preferably used for the textile fabrics. These textile fabrics have to be constantly scanned on the edges of the machine and, if they run out of the production direction, centered again to ensure trouble-free production. This process takes place mechanically and is very stressful. In the case of filter cloths, care must also be taken to ensure that the filtrate does not escape in an undesirable manner via the lateral edge of the textile fabric. To counteract these disadvantages, the edges are solidified by spraying with thermoplastics or by coating with cold-curing reactive resins (DE-OS 2 931 762).

Although this measure has led to a significant improvement, the elasticity and adhesion are not sufficient, especially with very fast-running machines.

The object of the invention is therefore to provide a method for edge hardening and edge sealing in which the elasticity, adhesion and hydrolysis strength of the sealing polymer material is improved. It has now been found that the shortcomings shown can be excluded by using radiation-curable ethylenically unsaturated compositions.

The invention thus relates to a method for edge strengthening and edge sealing of textile fabrics, characterized in that the edge zone of the fabric with radiation-curable resins, preferably consisting of prepolymer urethane (meth) acrylates and / or prepolymer polyester (meth) acrylates and / or prepolymer epoxy (meth) acrylates and / or d2, B unsaturated polyester resins and optionally reactive diluents, solvents, photoinitiators and accelerators, fillers and dyes are treated and then exposed to crosslinking radiation.

(Meth) acrylates are understood to be methacrylates, acrylates and both mixtures.

The proportion of the edge zone in the textile fabric can vary within wide limits depending on the intended use. Resins curable by UV light are preferably used together with the required photoinitiators and optionally accelerators.

The finishing process is that the radiation curable compositions e.g. are pressed into the textile material by means of doctor blade technology and then cured by means of crosslinking radiation. The viscosity of the radiation-curable compositions required for the application can be regulated by the use of polymerizable, low-viscosity diluents (reactive thinners) or solvents. Furthermore, the radiation-curable composition can be applied as an aqueous dispersion and can be crosslinked after the water has been removed.

• I) Strahlenhärtbare Polyurethan(meth)acrylate bestehend aus dem Umsetzungsprodukt aus
• A) 1 Grammäquivalent NCO eines Polyisocyanates mit 2-3, insbesondere 2 Isocyantgruppen pro Molekül,
• B) 0-0,8 Grammäquivalente OH eines Polyols mit mindestens 2, insbesondere 2-6 OH-Gruppen pro Molekül,
• C) 0,2-1,1 Grammäquivalente OH eines mindestens eine (Meth)Acryloyl- und mindestens eine OH-Gruppe enthaltenden Alkohols

wobei die Summe der OH-Grammäquivalente aus B und C 1,0-1,2, insbesondere 1-1,1 beträgt.Polyurethane (meth) acrylates, polyester (meth) acrylates, epoxy (meth) acrylates and α, B unsaturated polyesters with the following compositions are used as radiation-curable prepolymers:

• I) Radiation-curable polyurethane (meth) acrylates consisting of the reaction product
• A) 1 gram equivalent of NCO of a polyisocyanate with 2-3, in particular 2 isocyanate groups per molecule,
• B) 0-0.8 gram equivalents of OH of a polyol with at least 2, in particular 2-6 OH groups per molecule,
• C) 0.2-1.1 gram equivalents of OH of an alcohol containing at least one (meth) acryloyl and at least one OH group

the sum of the OH gram equivalents of B and C being 1.0-1.2, in particular 1-1.1.

A gram equivalent of NCO means the amount in grams of a compound that contains an isocyanate group. Accordingly, a gram equivalent of OH is the amount in grams of a compound containing a hydroxyl group.

• 2.4- und 2.6-Toluylendiisocyanat, Diphenylmethandiisocyanat, Isophorondiisocyanat, Xylylendiisocyanat, Hexamethylendiisocyanat oder das Umsetzungsprodukt von 3 Mol Hexamethylendiisocyanat und 1 Mol Wasser (Biuret). Die Polyisocyanate können mit di- und höherfunktionellen Polyolen oder Di- und Polyaminen mit mindestens zwei primären Aminogruppen zu präpolymeren Isocyanaten umgesetzt werden, wobei die Polyolkomponente auch ein Polyether- und/oder Polyesterpolyol sein kann (GB-PS 743 314 und US-PS 2 969 386).

The term polyisocyanate is understood to mean di- and higher-functional isocyanates, preferably di- and trifunctional, in particular difunctional. Examples include:

• 2.4- and 2.6-tolylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate or the reaction product of 3 moles of hexamethylene diisocyanate and 1 mole of water (biuret). The polyisocyanates can be reacted with di- and higher-functional polyols or di- and polyamines with at least two primary amino groups to form prepolymeric isocyanates, it also being possible for the polyol component to be a polyether and / or polyester polyol (GB-PS 743 314 and US Pat. No. 2,969 386).

Ureylen

und Oxycarbamyl-

enthalten können, oder Mischungen der Ganz besonders werden als Komponente B oxalkylierte aliphatische gesättigte Di- und/oder Triole mit OH-Zahlen von 100-1060 mg KOH/pro Gramm Substanz gegebenenfalls in Mischung mit aliphatischen gesättigten 2-4-wertigen, insbesondere 2-wertigen Polyolen mit einer OH-Zahl von 250-920, die mindestens eine Thiogruppe aufweisen, bevorzugt.Component B is understood to mean aliphatic saturated, 2-6-valent, preferably 2-4-valent polyols with OH numbers of 50-1830, preferably 100-1060 mg KOH / g substance or the aforementioned polyols, the aliphatic chain of which is one or more same or different groups of the series phenylene, cyclohexylene, oxy (-O-), thio (-S-), carboxylate

Ureylen

and oxycarbamyl

may contain, or mixtures of Oxygenated aliphatic saturated diols and / or triols with OH numbers of 100-1060 mg KOH / per gram of substance are optionally used as component B, optionally in a mixture with aliphatic saturated 2-4-valent, in particular divalent, polyols with an OH- Number of 250-920, which have at least one thio group, is preferred.

• a) Aliphatische gesättigte, 2-6-wertige Alkohole, insbesondere 2-4-wertige Alkohole wie Ethylenglykol, Propandiol-1,2, Propandiol-1,3, Neopentylglykol, Butandiol-1,4, Hexandiol-1,6, Dekandiol-1,10, Glycerin, Trimethylolpropan, Pentaerythrit, Dipentaerythrit sowie die Oxalkylierungsprodukte der 2-6-wertigen Alkohole mit 1,2-Alkylenoxiden wie Ethylenoxid oder Propylenoxid.
• b) Cycloaliphatische Diole wie Cyclohexandiol_-1,4 und 4,4-Dihydroxy-cyclohexyl-2,2-alkane, wie 4,4- Di- hydroxycyclohexyl-2,2-propan und araliphatische 2- wertige Alkohole, die gegebenenfalls 1-2 Ethersauerstoffatome enthalten wie bis-(oxethyliertes) Bisphenol A sowie (oxpropoxyliertes) Bisphenol A.
• c) Thioalkohole wie Oxalkylierungsprodukte von Schwefelwasserstoff oder Thiodiglykolen, wobei als Oxalkylierung sowohl Oxethylierung als auch Oxpropylierung in Frage kommt.
• d) Gesättigte oder ungesättigte, vorzugsweise gesättigte Polyester mit mindestens zwei freien Hydroxylgruppen aus den vorstehend beispielhaft genannten Alkoholen und mindestens einer Polycarbonsäure oder deren Anhydrid, insbesondere Dicarbonsäuren wie Maleinsäure Fumarsäure, Mesaconsäure, Citraconsäure, Itaconsäure, Bernsteinsäure, Isophthalsäure, Terephthalsäure, Trimellitsäure, Hexahydrophthalsäure, Tetrahydrophthalsäure, Endomethylentetrahydrophthalsäure, Methylhexahydrophthalsäure, Glutarsäure, Adipinsäure, Sebacinsäure, Phthalsäure. Die Polyalkohole a) bis d) der Komponente B können allein oder in Mischungen eingesetzt werden.

Examples of component B are:

• a) Aliphatic saturated 2-6-valent alcohols, especially 2-4-valent alcohols such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, decanediol- 1.10, glycerol, trimethylolpropane, pentaerythritol, dipentaerythritol and the oxyalkylation products of the 2-6-valent alcohols with 1,2-alkylene oxides such as ethylene oxide or propylene oxide.
• b) cycloaliphatic diols such as cyclohexanediol _- 1,4 and 4,4-dihydroxy-cyclohexyl-2,2-alkanes, such as 4,4-dihydroxycyclohexyl-2,2-propane and araliphatic dihydric alcohols, which may contain 1- 2 ether oxygen atoms contain such as bis- (oxyethylated) bisphenol A and (oxpropoxylated) bisphenol A.
• c) Thioalcohols such as oxyalkylation products of hydrogen sulfide or thiodiglycols, both oxethylation and oxpropylation being suitable as the oxyalkylation.
• d) Saturated or unsaturated, preferably saturated polyesters with at least two free hydroxyl groups from the above-mentioned alcohols and at least one polycarboxylic acid or its anhydride, in particular dicarboxylic acids such as maleic acid, fumaric acid, mesaconic acid, citraconic acid, itaconic acid, succinic acid, isophthalic acid, terephthalic acid, trimellitic acid, hexahydrophthalic acid, hexahydrophthalic acid, Tetrahydrophthalic acid, endomethylene tetrahydrophthalic acid, methylhexahydrophthalic acid, glutaric acid, adipic acid, sebacic acid, phthalic acid. The polyalcohols a) to d) of component B can be used alone or in mixtures.

Component C is any, preferably aliphatic hydroxyl groups and (meth) acryloyl group-containing compounds or mixtures of such compounds which (when mixtures are present on average) with a hydroxyl number (mg KOH / gram substance) of 20-600 , preferably 50-500, 1-3, preferably 1-2 hydroxyl groups per molecule and per 100 molecular weight units 1.12 to 0.01, preferably 0.9 to 0.09, in the form of the (meth) acryloyl groups present olefinic double bonds.

• Hydroxyalkyl(meth)acrylate wie z.B. 2-Hydroxyethylacrylat, 2-Hydroxypropylacrylat, 2-Hydroxybutylacrylat, 3-Hydroxypropylacrylat, 4-Hydroxybutylacrylat, und 6-Hydroxyhexyacrylat sowie die entsprechende (Meth)acrylate. Besonders werden 2-Hydroxyethylacrylat und 2-Hydroxypropylacrylat bevorzugt.

Typical examples of compound C are:

• Hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 3-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, and 6-hydroxyhexyacrylate and the corresponding (meth) acrylates. 2-Hydroxyethyl acrylate and 2-hydroxypropyl acrylate are particularly preferred.

Also suitable are esterification products of (meth) acrylic acid or transesterification products of (meth) acrylic acid esters, or reaction products of (meth) acrylic acid halides with the polyols mentioned under component B (ad), with 0 per mole of hydroxyl groups of the polyol from component B generally being 0 , 3-0.75 mol of the (meth) acryloyl compound can be used.

_I I. Radiation-curable epoxy (meth) acrylates consisting of reaction products of polyepoxides and (meth) acrylic acid, in the production of which 0.6-1.1 mol (meth) acrylic acid and 0-0.5 mol saturated per mole of epoxy groups, ie per epoxy equivalent Monocarboxylic acid, preferably 0.9-1.1 mol (meth) acrylic acid, can be used. In this context, the term polyepoxide is understood to mean compounds which (on statistical average) contain more than one 1,2-epoxide groups per molecule, preferably 1.6 to 6, in particular 1.6 to 3, epoxide groups.

The polyepoxide compounds can be, for example, polyglycidyl ethers of polyhydric phenols, for example those of pyrocatechol, resorcinol, hydroquinone, 4,4'-dihydroxydiphenylmethane, 4,4'-dihydroxydiphenyldimethylmethane (bisphenol A) 4,4'-dihydroxydiphenylmethylmethane, 4,4'-dihydroxydiphenylcyclohexane the diphenols mentioned 4.4 ^1- dihydroxydiphenyl sulfone, tris (4-hydroxyphenyl) -methane, the chlorination and bromination products, especially those from bisphenol A, novolacs (that is, reaction products of mono- or polyhydric phenols with aldehydes, particularly formaldehyde in the presence of acidic catalysts), of diphenols, by the esterification of 2 moles of the sodium salt of an aromatic oxycarbon Acid were obtained with one mole of a dihaloalkane or dihalodialkyl ether (GB-PS 1 017 612) or of polyphenols which were obtained by condensation of phenols and long-chain halogen paraffins containing at least 2 halogen atoms (GB-OS 1 o24 288).

Glycidyl ethers of polyhydric alcohols from 1,4-butanediol, 1,4-butenediol, glycerol, trimethylolpropane, pentaerythritol and polyethylene glycols may also be mentioned. Of further interest are triglycidyl isocyanurate and N, N'-diepoxypropyloxamide.

worin A ein mindestens 2-wertigen Rest eines gegebenenfalls durch Sauerstoff und/oder cycloaliphatische Ringe unterbrochenen aliphatischen Kohlenwasserstoffs, R Wasserstoff oder Alkylreste mit 1-3 C-Atomen und n eine Zahl zwischen 2-6 bedeuten, oder Mischungen von Glycidylcarbonsäureestern der angegebenen allgemeinen Formel (GB-PS 1 220 702).Also suitable are: Glycidyl esters of polyvalent aromatic, aliphatic and cycloaliphatic carboxylic acids, for example diglycidyl phthalate, diglycidyl isophthalate, diglycidyl terephthalate, diglycidyl tetrahydrophthalate and diglyididyl ester of adipic acid, diglyididyl ester, methyl diglyididyl ester, and diglycidyl ester adipic acid, from 1 mole of an aromatic or cycloaliphatic dicarboxylic anhydride and 1/2 mole of a diol or 1 / n mole of a polyol with n hydroxyl groups, such as glycidyl carboxylic acid esters of the general formula

wherein A is an at least divalent radical of one optionally by oxygen and / or cycloaliphatic rings interrupted aliphatic hydrocarbon, R is hydrogen or alkyl radicals with 1-3 C atoms and n is a number between 2-6, or mixtures of glycidyl carboxylic acid esters of the general formula given (GB-PS 1 220 702).

Preferred polyepoxide compounds are polyglycidyl ethers of polyhydric phenols, in particular from bisphenol A, diglycidyl phthalate, diglycidyl isophthalate, diglycidyl terephthalate, polyglycidyl esters from cycloaliphatic dicarboxylic acid and hexahydrophthalic acid and diglyhydride from dimethyidide from = integer from 2-6), in particular from 3 mol of hexahydrophthalic anhydride and / or phthalic anhydride and one mol of 1,1,1-trimethylolpropane.

Suitable monocarboxylic acids are acids of the formula H (CH ₂ ) _n COOH with n = 0 to 20, in particular acetic acid. The polyepoxides mentioned can also be pre-extended by reaction with aliphatic or aromatic dicarboxylic acids, with dimercaptans or H ₂ S or with amines or ammonia if a higher molecular weight of this starting component is desired.

III. Radiation-curable prepolymeric polyester (meth) acrylates with an acid number (mg KOH per g substance) of at most 20, preferably at most 10, particularly preferably at most 5 with an ethylenically unsaturated double bond content of from 1.12 to 0.01, in particular from 0.8 to 0.1 per 100 molecular weight units.

• a) Acrylsäure, Methacrylsäure, aliphatischen und/ oder aromatischen Dicarbonsäuren wie Adipinsäure, Bernsteinsäure, Glutarsäure, Pimelinsäure, Korksäure, Cyclohexandicarbonsäure, Sebacinsäure, Azelainsäure, Phthalsäure, Tetrahydrophthalsäure, Hexahydrophthalsäure, Terephthalsäure, Maleinsäure, Fumarsäure sowie deren Anhydriden bzw. Derivaten und mehrwertigen Alkoholen wie Ethylenglykol, Propylenglykol (1,2 und 1,3), Butandiol (1,2 und 1,4), Hexandiol, Neopentylglykol, Glyzerin, Trimethylolpropan, Dimethylolpropan, Pentaerythrit sowie deren Oxalkylierungsprodukten, wobei die Oxalkylierung sowohl Oxethylierung als auch Oxpropylierung umfaßt.
• b) den vorstehend unter III a) genannten Alkoholen und Acrylsäure und/oder Methacrylsäure.

Typical examples of the prepolymeric polyester (meth) acrylates are made up of:

• a) acrylic acid, methacrylic acid, aliphatic and / or aromatic dicarboxylic acids such as adipic acid, succinic acid, glutaric acid, pimelic acid, suberic acid, cyclohexanedicarboxylic acid, sebacic acid, azelaic acid, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, terephthalic acid, maleic acid, fumaric acid, and their anhydrides or derivatives and polyhydric alcohols such as Ethylene glycol, propylene glycol (1,2 and 1,3), butanediol (1,2 and 1,4), hexanediol, neopentyl glycol, glycerin, trimethylolpropane, dimethylolpropane, pentaerythritol and their oxyalkylation products, the oxyalkylation comprising both oxethylation and oxpropylation.
• b) the alcohols mentioned above under III a) and acrylic acid and / or methacrylic acid.

oC, ß-ethylenically unsaturated polyesters are the usual polycondensation products of at least one oα, ß-ethylenically unsaturated dicarboxylic acid with 4 or 5 carbon atoms or their ester-forming derivatives, optionally in a mixture with up to 90 mol%, based on the unsaturated acid components, of at least one aliphatic with 4-10 C atoms or cycloaliphatic or aromatic dicarboxylic acid with 8-10 C atoms or their ester-forming derivatives with at least one polyhydroxy compound, in particular dihydroxy compound having 2-8 carbon atoms (J. Björksten et al., "Polyesters and Their Applications", Reinhold _P ublishing Corp., New _Y ork, 1956).

Examples of preferred unsaturated dicarboxylic acids or their derivatives are maleic acid or maleic anhydride and fumaric acid. However, mesaconic acid, citraconic acid, itaconic acid or chloromaleic acid can also be used, for example. Examples to be used aliphatic, cyclo-aliphatic and aromatic dicarboxylic acids or their derivatives are phthalic acid or phthalic anhydride, isophthalic acid, terephthalic acid, tetrahydrophthalic acid or chlorides _H EXA or their anhydrides, endomethylene or its anhydride, succinic acid or succinic anhydride and Bernsteinsäureester and, Adipic acid, sebacic acid. Ethylene glycol, 1,2-propanediol, 1,3-propanediol, diethylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, 2,2-bis (4- hydrocyclohexyl) propane, bis-oxyalkylated bisphenol A, perhydrobisphenol and others are used. Ethylene glycol, 1,2-propanediol, diethylene glycol and dipropylene glycol are preferably used.

Further modifications are possible by incorporating mono-, tri- and tetravalent alcohols with 1-6 C atoms, such as methanol, ethanol, butanol, allyl alcohol, benzyl alcohol, cyclohexanol and tetrahydrofurfuryl alcohol, trimethylolpropane, glycerin and pentaerythritol as well as mono-, di -and triallyl ethers and benzyl ethers trihydric and polyhydric alcohols with 3-6 C atoms according to DB-AS 1 024 654, and by incorporating monobasic acids such as benzoic acid or long-chain unsaturated fatty acids such as oleic acid, linseed oil fatty acid and ricin fatty acids.

The acid numbers of the polyesters should be between 1 and 100, preferably between 20 and 70, the OH numbers between 10 and 150, preferably between 20 and 100, and the number-average molecular weights X between about 500 and 5000, preferably between 1000 and 3000 (Measured by vapor pressure osmometry in dioxane and acetone; if the values differ, the lower one is considered the correct one).

The unsaturated polyesters and their preparation have been described in detail, for example, in DE-AS 1 024 654, 1 054 620 and 2 221 335.

The preparation of the radiation-curable prepolymeric urethane acrylates given under I. the reaction of the polyisocyanate with alcohols and polyols containing (meth) acrylol groups can e.g. at temperatures of 20-90 ° C, preferably at 40-70 ° C, in a one-pot process or in several stages. In a multi-stage process, the reaction of the polyisocyanate with the ethylenically unsaturated alcohol in the first stage, followed by the addition of the polyol in the second stage, is preferred.

The urethane formation reaction can be catalyzed in a manner known per se, for example with tin octoate, dibenzyltin dilaurate, caprolactam or tertiary amines. As well The (meth) acrylic-containing oligoalcohols according to the invention containing urethane groups can be protected from premature and undesired polymerization by adding suitable inhibitors and antioxidants, in each case 0.001-0.1% by weight, based on the mixture as a whole.

The (meth) acryloyl group-containing alcohols (component C) required to build up the radiation-curable prepolymer urethane (meth) acrylates are known or can be obtained by a known process.

The radiation-curable epoxy (meth) acrylates specified under II can be prepared by reacting 0.6-1.1 mol (meth) acrylic acid and 0-0.5 mol monocarboxylic acid, preferably 0.9-1.1 mol (meth) Acrylic acid, with 1 gram equivalent of epoxy of a polyepoxide, with reaction products with acrylic acid being preferred.

The addition of acrylic and / or methacrylic acid to the polyepoxides is carried out by known methods, for example by the processes of US Pat. No. 3,301,743 or US Pat. No. 2,324,851 in bulk or in solvents such as butyl acetate, ethyl acetate, acetone, Ethyl methyl ketone, diethyl ketone, cyclohexane, cyclohexanone, cyclopentane, cyclopentanone, n-heptane, n-hexane, n-octane, isooctane, methylene chloride, chloroform, 1,1-dichloroethane, 1,2-dichloroethane, 1,1,2-trichloroethane, Carbon tetrachloride. If desired, the addition of the (meth) acrylic acid in the presence of about 0.01-3 wt .-%, based on the starting epoxide on catalysts such as tert. Amines, alkali metal hydroxides, alkali metal salts of organic carboxylic acids, bis (hydroxyalkyl) sulfides, sulfonium, phosphonium compounds, phosphines, amines or stibines can be carried out. Reaction temperatures of 40 to 90 ° C. have proven to be expedient, which, however, can be exceeded up or down in special cases. In order to protect the resulting reaction products from undesirable premature polymerization, it is advisable to add polymerization inhibitors, based on the mixture as a whole, to 0.001-0.1% by weight during the preparation.

The preparation of the radiation-curable prepolymeric polyester (meth) acrylates specified under III can be carried out in a one-step process by esterification of the components specified under III a / b, preferably under acid-catalyzed azeotropic conditions, by transesterification of the alcohols specified under III a / b or from the alcohols and dicarboxylic acids listed under III a / b by esterifying polyols with suitable (meth) acrylic acid esters, preferably using a transesterification catalyst or by reacting (meth) acrylic acid halides with the alcohols listed under III a / b or from the under III a / b listed alcohols and dicarboxylic acids obtained by esterification polyols preferably in the presence of a basic auxiliary such as tert. Amines are carried out according to the usual methods of organic chemistry.

The radiation-curable prepolymeric polyester (meth) acrylates listed under III are preferably prepared in a manner known per se by acid-catalyzed esterification in the presence of an entrainer and the customary polymerization inhibitors.

Commercially available organic and inorganic acids or acidic ion exchangers serve as esterification catalysts. P-Toluenesulfonic acid is particularly preferred in amounts of 0.1 to 3% by weight, based on the sum of the amounts by weight of (meth) acrylic acid and polyols. Suitable entraining agents for removing the water of reaction are suitable aliphatic, cycloaliphatic or aromatic hydrocarbons and their chlorination products or mixtures thereof, in particular those having a boiling range between 40 ° C. and 140 ° C., preferably 70 ° C. to 120 ° C. Preferred hydrocarbons are, for example, hexane and its isomers, cyclohexane and in particular toluene. The amounts of entrainer ah can be 10-60% by weight, based on the sum of the amounts by weight of (meth) acrylic acid and polyol.

In general, the amount of entrainer is measured so that azeotropic dewatering is ensured and the bottom temperature of the reaction mixture does not exceed a temperature of 120-140 ° C.

The radiation-curable prepolymeric polyurethane (meth) acrylates, epoxy (meth) acrylates and polyester (meth) acrylates generally contain sufficient polymerization inhibitors to protect them from premature polymerization. In the cases where the inhibiting effect of the polymerization inhibitors used in the preparation is insufficient, post-stabilization with the customary inhibitors can be carried out without difficulty.

Suitable auxiliaries of this type are, for example, phenols and phenol derivatives, preferably sterically hindered phenols, which contain alkyl substituents with 1-6 C atoms in both _O positions to the phenolic hydroxyl group, amines, preferably secondary arylamines and their derivatives, quinones, copper-1 salts of organic acids or addition compounds of copper (I) halides with phosphites.

The radiation-curable prepolymer compositions according to the invention can in some cases be used without the addition of copolymerizable monomers or solvents. However, since in many cases the products are viscous, it is advisable, in order to support the penetration of the masses into the textile fabric and / or to vary the properties of the curing products, to mix them with copolymerizable monomers.

• 1. Ester der Acryl- oder Methacrylsäure mit aliphatischen C₁-C₈-, cycloaliphatischen C₅-C₆-, araliphatischen C₇-C₈- Monoalkoholen, beispielsweise Methylacrylat, Ethylacrylat, n-Propylacrylat, n-Butylacrylat, Methylhexylacrylat, 2-Ethylhexylacrylat, Cyclopentylacrylat, Cyclohexylacrylat, 5-Ethyl-methylolacryloyl-dioxan-1,3, Benzylacrylat, ß-Phenylethylacrylat oder die entsprechenden Methacrylsäureester;
• 2. Di- und Polyacrylate sowie Di- und Polymethacrylate von Glykolen mit 2 bis 6 C-Atomen und Polyolen mit 3-4 Hydroxylgruppen und 3 bis 6 C-Atomen, wie Ethylenglykoldiacrylat, Propandiol-1,3-diacrylat, Butandiol-1,4-diacrylat, Hexandiol-1,6-diacrylat, Trimethylolpropan-triacrylat, Pentaerythrit-tri- und tetraacrylat sowie entsprechende Methacrylate, ferner Di(meth)acrylate von Polyetherglykolen des Glykols, Propandiol-1,3, Butandiol-1,4, tetraoxethyliertes Trimethylolpropan-trisacrylat;
• 3. Aromatische Vinyl- und Divinylverbindungen, wie Styrol, Methylstyrol, Divinylbenzol;
• 4. N-Methylolacrylamid oder N-Methylolmethacrylamid sowie entsprechende N-Methylolalkylether mit 1-4 C-Atomen in der Alkylethergruppe bzw. entsprechende N-Methylolallylether, insbesondere N-Methoxymethyl-(meth)acrylamid, N-Butoxymethyl(meth)acrylamid und N-Allyloxymethyl(meth)acrylamid.
• 5. Vinylalkylether mit 1-4 C-Atomen in der Alkylgruppe wie Vinylmethylether, Vinylethylether, Vinylpropylether, Vinylbutylether;
• 6. Trimethylolpropan-diallylethermono(meth)acrylat, Vinylpyridin, N-Vinylcarbazol, Triallylphosphat, Triallylisocyanurat und andere.

Copolymerizable monomers suitable for blending are:

• 1. esters of acrylic or methacrylic acid with aliphatic C ₁ -C ₈ -, cycloaliphatic C ₅ -C ₆ -, araliphatic C ₇ -C ₈ - monoalcohols, for example methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, methylhexyl acrylate, 2 Ethylhexyl acrylate, cyclopentyl acrylate, cyclohexyl acrylate, 5-ethyl-methylolacryloyl-dioxane-1,3, benzyl acrylate, β-phenylethyl acrylate or the corresponding methacrylic acid ester;
• 2. Di- and polyacrylates as well as di- and polymethacrylates of glycols with 2 to 6 carbon atoms and polyols with 3-4 hydroxyl groups and 3 to 6 carbon atoms, such as ethylene glycol diacrylate, propanediol-1,3-diacrylate, butanediol-1, 4-diacrylate, hexanediol-1,6-diacrylate, trimethylolpropane triacrylate, pentaerythritol tri and tetraacrylate and corresponding methacrylates, also di (meth) acrylates of polyether glycols of glycol, 1,3-propanediol, 1,4-butanediol, tetraoxethylated trimethylolpropane trisacrylate;
• 3. Aromatic vinyl and divinyl compounds, such as styrene, methylstyrene, divinylbenzene;
• 4. N-methylol acrylamide or N-methylol methacrylamide and corresponding N-methylol alkyl ethers with 1-4 C atoms in the alkyl ether group or corresponding N-methyl olallyl ether, in particular N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide and N -Allyloxymethyl (meth) acrylamide.
• 5. vinyl alkyl ethers with 1-4 C atoms in the alkyl group such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, vinyl butyl ether;
• 6. Trimethylolpropane diallyl ether mono (meth) acrylate, vinyl pyridine, N-vinyl carbazole, triallyl phosphate, triallyl isocyanurate and others.

Group 1 copolymerizable monomers, in particular 5-ethyl-5-methylolacryloyl-dioxane-1,3, are particularly preferred.

Mixtures of one or more of the aforementioned monomers can also be used. The additives can be about 0-70% by weight, preferably 0-40% by weight, based on the mixture of the radiation-curable ones. Dimensions.

If desired, it is possible to coat the radiation-curable compositions with inert solvents such as butyl acetate, Ethyl acetate, acetone, ethyl methyl ketone, diethyl ketone, cyclohexane, cyclohexanone, cyclopentane, cyclopentanone, n-heptane, n-hexane, n-octane, isooctane, toluene, xylene, methylene chloride, chloroform, 1,1-dichloroethane, 1,2-dichloroethane, Mix 1,1,2-trichloroethane, carbon tetrachloride, methanol, ethanol, isopropanol, butanol.

The additives can be about 0-50% by weight, preferably 0-40% by weight, based on the mixture of the radiation-curable composition. However, solvent-free radiation-curable compositions are preferably used in the process according to the invention. Of course, it is also possible to use mixtures of additional monomers and solvents within the stated proportions. To reduce the viscosity of the radiation-curable compositions, it is also possible to heat the formulation to temperatures up to 120 ° C., preferably up to 80 ° C., before application to the textile fabric. Furthermore, the radiation-curable compositions according to the invention can also be applied with the aid of external emulsifiers and, if appropriate, customary auxiliaries used in emulsion technology in water. Anionic, nonionic, cationic, ampholytic or high molecular weight substances and their mixtures are suitable as emulsifiers. Corresponding emulsifiers are, for example, in Ullmann's encyclopedia of techn. Chemistry, volume 10, 4th edition, chapter emulsions, p. 449 ff. Suitable emulsifiers can be easily and quantitatively determined by simple manual tests.

The emulsions can contain 10 to 80% by weight, preferably 30 to 70% by weight, of the radiation-curable compositions. The radiation-curable compositions can be cured by means of high-energy radiation, such as UV light, electron beams, gamma rays or in the presence of radical-donating substances, such as thermal polymerization initiators. The radiation-curable compositions are preferably cured by means of the high-energy radiation mentioned. The radiation-curable compositions are preferably cured by the influence of UV light. The addition of photoinitiators is required for this application. Suitable photoinitiators are the compounds customarily used for this purpose, for example benzophenone and very generally aromatic ketone compounds which are derived from benzophenone, such as alkylbenzophenones, halogen-methylated benzophenones according to DE-OS 1 949 010, Michler's ketone, anthrone, halogenated benzophenones. Benzoin and its derivatives are also suitable, for example according to DE-OS 1 769 168, 1 769 853, 1 769 854, 1 807 297, 1 807 301, 1 919 678 and DE-AS 1 694 149. Anthraquinone and represent numerous of its derivatives, for example β-methylanthraquinone, tert-butylanthraquinone and anthraquinone carboxylic acid esters, as well as oxime esters according to DE-OS 1 795 089. Phenylglyoxylic acid esters according to DE-OS 2 825 955 are also suitable.

Particularly suitable photoinitiators are benzil dimethyl ketal, benzoin ether, phenylglyoxylate according to DE-OS 2 825 955 and the system benzophenone / amine according to US Pat. No. 3,759,807. The photo initiators most suitable for the respective photo-crosslinkable system can be determined by a few simple manual tests.

Particularly suitable for the irradiation of the textile fabric provided with the radiation-curable composition according to the invention are the light sources customary in reproduction technology, the emission of which is generally in the range from 250 to 500 nm, preferably 300 to 400 nm. Examples of suitable light sources are carbon arc lamps, xenon lamps, UV fluorescent lamps, low-pressure mercury lamps, high-pressure mercury lamps which, in addition to visible light, provide a particularly effective proportion of ultraviolet light for the polymerization. The exposure time depends on the type of light source used. Irradiation can take place at room temperature, but it can also be carried out at elevated temperatures.

Often it can be beneficial e.g. to improve the mechanical properties of the textile fabric finished by the process according to the invention, to use further additives. Mixing with e.g. saturated or unsaturated polyesters or selected enhancers, fillers or dyes, antistatic agents, water repellents or flame retardants are quite possible. The additives are preferably used in amounts of 1-50% by weight, based on the polymerizable components. In principle, only such additives should be used and their amount limited to such an extent that the reactivity is not impaired. If fillers or dyes are used in the UV-curable mass, their use is limited to those which do not suppress the polymerization process due to their absorption behavior.

If the curing by high-energy radiation, for example electron beam radiation or i ^r- radiation, so in principle all fillers, pigments and reinforcing materials, such as those used commonly usable. The radiation-curable compositions can be applied to the substrates by spraying, impregnation, brushing or printing. If they are applied from an aqueous emulsion or aqueous solution, they are freed from the water by drying in a suitable unit before curing.

Suitable substrates are, for example, textile fabrics such as woven fabrics, knitted fabrics, laid scrims, nonwovens, networks made of natural or synthetic fibers, and mineral fibers are also suitable.

• Die Viskositäten wurden entweder im 4-mm Auslaufbecher nach DIN 53 211 (Angabe in Sekunden) oder mit einem Viscotester der Firma Haake, Typ VI 02V (Angabe in P Meßbereich bis 4000) bestimmt. Als Belichtungsquelle wurden Quecksilberhochdruckstrahler der Fa. Philips (HPK, Leistungsaufnahme 125 W) oder Quecksilberhochdruckstrahler der Fa. Hanovia (Leistungsaufnahme 80 W/cm) oder Quecksilberniederdrucklampen der Fa. Philips (TL 05) benutzt.

The following explanations are common to the examples:

• The viscosities were determined either in a 4 mm flow cup according to DIN 53 211 (specified in seconds) or with a Viscotester from Haake, type VI 02V (specified in P measuring range up to 4000). High-pressure mercury lamps from Philips (HPK, power consumption 125 W) or high-pressure mercury lamps from Hanovia (power consumption 80 W / cm) or low-pressure mercury lamps from Philips (TL 05) were used as the exposure source.

example 1

A urethane acrylate is prepared by reacting isophorone diisocyanate, hydroxyethyl acrylate, thiodiglycol and an oxyethylated trimethylolpropane with an OH number (mg KOH / g substance) of 250 and with 5-ethyl-5-methylolacryloyldioxane-1,3 (US Pat. No. 40,767,727 ) mixed as a reactive diluent.

After introducing 1065.6 g of isophorone diisocyanate, 0.11 g of tin octoate and 0.53 g of 2,5-di-tert-butylhydroquinone, 445.4 g of hydroxyethyl acrylate are added dropwise at a bottom temperature of 50-60 ° C. while stirring and passing dry air . After an NCO value of 16.1% by weight has been reached, 3.1 g of tin octoate are added and 74.88 g of thiodiglycol and 1080 g of an ethoxylated trimethylolpropane with an OH number of 250 are added dropwise while maintaining the internal temperature. The mixture is mixed with 1776 g of 5-ethyl-5-methylolacryloyldioxane-1,3 and stirred at 65 ° C. until the NCO value is less than 0.1% by weight. A radiation-curable composition with a viscosity of 250 P (23 ° C) is obtained.

Example 2

A urethane acrylate is prepared by reacting isophorone diisocyanate and the reaction product of acrylic acid with an oxyethylated trimethylolpropane (OH number 550 mg KOH / g substance).

925 g of ethoxylated trimethylolpropane are mixed with 430 g of acrylic acid, 12 g of p-toluenesulfonic acid, 1 g of p-methoxyphenol 1.2 g of 2,5-di-tert-butylhydroquinone and 280 g of toluene were heated to reflux while passing air through them and the water of reaction formed was removed azeotropically. After an acid number of less than 5 (mg KOH / g substance) has been reached, the solvent is removed in vacuo and the OH group-containing (OH number 105-115) ethylenically unsaturated partial ester is filtered. 1060 g of this ester and 0.44 g of tin octoate are heated to 50-60 ° C. in a stirring apparatus and 222 g of isophorone diisocyanate are added while passing dry air over them. The mixture is stirred while maintaining the internal temperature until the NCO value is less than 0.1% by weight. A light urethane acrylate with a viscosity of 400-500 P (22 ° C) is obtained.

Example 3

800 g of urethane acrylate according to Example 2 are mixed with 200 g of 1,3-5-ethyl-5-methylolacryloyldioxane. A light urethane acrylate with a viscosity of 150 P (23 ° C) is obtained.

Example 4

An epoxy acrylate is obtained by reacting a bisphenol A diglycidyle epoxide (epoxy equivalent 190), acrylic acid, acetic acid and ethanolamine. The epoxy acrylate is mixed with 5-ethyl-5-methylolacryloyldioxane-1,3.

1892 g of bisphenol A diglycidyl epoxide, 1.909 g of thiodiglycol are placed in a stirring apparatus and 30.5 g of ethanolamine are added dropwise at 65-70 ° C. under nitrogen. After three hours of stirring at 80 ° C., 1.4 g of p-methoxyphenol, 1.4 g of 2,5-di-tert-butylhydroquinone and 19.2 g of thiodiglycol are added, and 450 g of acrylic acid are added dropwise in the course of 3 hours. The mixture is stirred at a bottom temperature of 80 ° C. while passing over dry air until the acid number is less than 10. Then 1.8 g of thiodiglycol, 152 g of acetic acid and 850 g of 5-ethyl-5-methylolacryloyl-dioxane-1,3 are added and the mixture is stirred at 80 ° C. until the acid number is less than 5. A radiation-curable composition with a viscosity of 3000 P (22 ° C.) is obtained.

Example 5

A polyester acrylate is produced by azeotropic esterification of maleic anhydride, ethylene glycol, succinic anhydride, trimethylol propane and acrylic acid.

There are 166.6 g of maleic anhydride, 21o, 8 g of ethylene glycol, 34o g of succinic anhydride in the presence of o, 71 g of 2,5-di-tert-butylhydroquinone, 0.71 g of p-methoxyphenol and 3.57 g of p-toluenesulfonic acid esterified azeotropically with toluene as entrainer while passing a light air stream. The course of the reaction is followed by the amount of water carried out. After the elimination of water has ended, 455.6 g of trimethylolpropane, 538.5 g of acrylic acid, 1.01 g of 2,5-di-tert-butylhydroquinone, 1.01 g of p-methoxyphenol and 4.98 g of p-toluenesulfonic acid are added and the mixture is further esterified azeotropically until no more water of reaction is separated off. After the entrainer has been distilled off and excess acrylic acid has been desorbed, a radiation-curable polyester acrylate having a viscosity of 80 P (50 ° C.) is obtained.

Example 6

A polyester acrylate is prepared according to Example 5 by azeotropic esterification, with the change that 251.6 g of phthalic anhydride are used instead of maleic anhydride. After the entrainer has been distilled off and excess acrylic acid has been desorbed, a radiation-curable polyester acrylate having a viscosity of 410 P (50 ° C.) is obtained.

Example 7

500 g of polyester acrylate from Example 5 are mixed with 333.33 g of 5-ethyl-5-methylolacryloyl-dioxane-1,3. A radiation-curable composition with a viscosity of 100 P (20 ° C) is obtained.

Example 8

500 g of polyester acrylate according to Example 6 are mixed with 333.33 g of 5-ethyl-5-methylolacryloyldioxane _- 1.3.

A radiation-curable composition with a viscosity of 110 P (20 ° C.) is obtained.

Example 9

A polyester acrylate is produced by azeotropic esterification of adipic acid, propylene glycol, succinic anhydride, trimethylolpropane and acrylic acid.

146 g of adipic acid, 152 g of 1,2-propylene glycol, 200 g of succinic anhydride in the presence of 0.5 g of di-tert-butylhydroquinone, 0.5 g of p-methoxyphenol and 2.49 g of p-toluenesulfonic acid with toluene as an entrainer esterified azeotropically while passing a light air stream. The course of the reaction is followed by the amount of water carried out. After the elimination of water has ended, 268 g of trimethylolpropane, 288 g of acrylic acid, 2.95 g of p-toluenesulfonic acid, 0.59 g of di-tert-butylhydroquinone and 0.59 g of p-methoxyphenol are added to the reaction mixture and further azeotropically esterified until no more water of reaction is separated. After distillation of the entrainer and desorption of unreacted acrylic acid, a radiation-curable polyester acrylate with a viscosity of 180 P (50 ° C.) is obtained, which is in a 2.75% aqueous, partially hydrolyzed PVA solution with the addition of 0.5% of an emulsifier mixture of alkylarylsulfonic acids and ethoxylated nonylphenol can be emulsified.

application Example 10

The radiation-curable polymer from Example 1 is applied in the presence of 3% of a photoinitiator (benzil dimethyl ketal) by means of a doctor blade technique in strips to a side edge of a rectangular grid fabric made of polyester filaments in a width of 50 mm and under UV light (Hanovia lamp, 80 W / cm, distance 8 cm, belt speed 5 m / min.) cured. The lattice fabric is then turned over and subjected to the same procedure, so that the radiation-curable composition, when crosslinked, extends from surface to back through the entire edge. The process is repeated on the other side edge.

The grid fabric reinforced on both sides in this way is used as a screen belt in a paper machine.

Example 11

The radiation-curable composition from Example 2 is heated to 50 ° C. in the presence of 3% of a photoinitiator (benzoin isopropyl ether) in a heatable tub. The side edges of a square synthetic fiber fleece made of polypropylene fibers, with a width of 50 mm, are immersed in the tub. The fleece is pulled out of the immersion bath and freed of excess polymer between a pair of rollers, the gap opening of which is set to the thickness of the fleece. The mass is obtained by exposure to UV light on both sides (Hanovia Spotlight 80 W / cm, distance 8 cm, belt speed 5 m / min.) Hardened. This process is repeated on the remaining edges of the nonwoven fabric, so that the edge is completely filled with polymer. The fleece is used as a filter in filter presses.

Claims (4)

1. A method for edge consolidation and edge sealing of textile fabrics, characterized in that the edge zone of the fabric is treated with radiation-curable materials and is exposed to crosslinking radiation. 2. The method according to claim 1, characterized in that prepolymer urethane (meth) acrylates and / or prepolymer polyester (meth) acrylates and / or prepolymer epoxy (meth) acrylates and / or α, β-unsaturated polyester resins are used as radiation-curable compositions . 3. The method according to claim 1, characterized in that the radiation-curable compositions are cured in the presence of photoinitiators and optionally accelerators with UV light. 4. The method according to claim 1, characterized in that the radiation-curable compositions are applied as an aqueous emulsion or solution and the water is removed before the irradiation.