Process for bulk dyeing of plastics

Abstract

A process for bulk dyeing of plastics comprising the step of adding a dye of the formula (I) wherein Y is a bivalent radical selected from the group consisting of substituted and unsubstituted arylenes and alkylenes, and substituted and unsubstituted alkylene radicals interrupted in the main chain by heteroatoms such as O or S, R 1 and R 1 ′, independently of one another, are an electron-withdrawing group, R 2 , R 2 ′, R 3 and R 3 ′, independently of one another are hydrogen, alkyl, R 4 and R 4 ′, independently of one another, are unsubstituted or substituted alkyl. to plastic.

What is claimed is:  
     
         1 . A process for bulk dyeing of plastics comprising the step of adding a dye of the formula (I)  
                   
       wherein 
 Y is a bivalent radical selected from the group consisting of substituted and unsubstituted arylenes and alkylenes, and substituted and unsubstituted alkylene radicals interrupted in the main chain by heteroatoms such as O or S,  
 R 1  and R 1 ′, independently of one another, are an electron-withdrawing group,  
 R 2 , R 2 ′, R 3  and R 3 ′, independently of one another are hydrogen, alkyl,  
 R 4  and R 4 ′, independently of one another, are unsubstituted or substituted alkyl.  
 to plastic.  
 
     
     
         2 . The process of    claim 1   , wherein R 1  and R 1 ′, independently of one another, are cyano or alkoxycarbonyl.  
     
     
         3 . The process of    claim 2   , wherein the alkoxycarbonyl is C 1 -C 4 -alkoxycarbonyl.  
     
     
         4 . The process of    claim 1   , wherein R 2 , R 2 ′, R 3  and R 3 ′ are independently of one another are C 1 -C 4 -alkyl, CF 3  or halogen.  
     
     
         5 . The process of    claim 4   , wherein the halogen is F or Cl,  
     
     
         6 . The process of    claim 1   , wherein R 4  and R 4 ′, independently of one another, are unsubstituted or substituted C 1 -C 6 -alkyl, or C 7 -C 12 -aralkyl.  
     
     
         7 . The process of    claim 6   , wherein R 4  and R 4 ′ are benzyl.  
     
     
         8 . The process of    claim 1   , wherein Y is selected from the group consisting of 1,3-phenylene, 1,4-phenylene, methyl-substituted 1,3- or 1,4-phenylene, unsubstituted or substituted C 2 -C 6 -alkylene.  
     
     
         9 . The process of    claim 1   , wherein the unsubstituted or substituted C 2 -C 6 -alkylene, is —CH 2 —CH 2 —, —CH 2 CH 2 CH 2 —, —(CH 2 ) 4 —, —CH 2 CH(CH 3 )—, —CH 2 CH 2 OCH 2 CH 2 - or —CH 2 CH-S—CH 2 CH 2 —.  
     
     
         10 . The process of    claim 1   , wherein R 1  and R 1 ′, independently of one another, are CN, CO 2 CH 3 , CO 2 CH 2 CH 3 , —CO 2 (CH 2 ) 2 CH 3  or CO 2 (CH 2 ) 3 CH 3 .  
     
     
         11 . The process of    claim 1   , wherein R 2 , R 2 ′, R 3  and R 3 ′, independently of one another, are hydrogen, methyl, ethyl, Cl, F or CF 3 .  
     
     
         12 . The process of    claim 1   , wherein R 4  and R 4  are CH 3 , ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl or tert-butyl.  
     
     
         13 . The process of    claim 1   , wherein R 1  R 1 ′, R 2 ═R 2 ′, R 3 ═R 3 ′ and R 4 ═R 4 ′.  
     
     
         14 . The process of    claim 1   , wherein the dyes is of the formula (Ia)  
                   
       wherein 
 Y is 1,3- phenylene, 1,4-phenylene, ethylene, propylene or butylene,  
 R 1  is CN, CO 2 CH 3 , CO 2 CH 2 CH 3  or CO 2 (CH 2 ) 3 CH 3 ,  
 R 2  is hydrogen, CH 3  or CH 2 CH 3 , and  
 R 4  is CH 3 , CH 2 CH 3 , n-propyl or n-butyl.  
 
     
     
         15 . The process of    claim 1   , wherein at least one of the substituent pairs R 1 /R 1 ′, R 2 /R 2 ′, R 3 /R 3  and/or R 4 /R 4 ′ is non-identical.  
     
     
         16 . The process of    claim 1   , wherein the dye is (A) or (B):  
                   
     
     
         17 . A compound of the formula  
                   
       wherein 
 Y is a bivalent radical selected from the group consisting of substituted and unsubstituted arylenes and alkylenes, and substituted and unsubstituted alkylene radicals interrupted in the main chain by heteroatoms such as O or S,  
 R 1  and R 1 ′, independently of one another, are an electron-withdrawing group,  
 R 2 , R 2 ′, R 3  and R 3 ′, independently of one another are hydrogen, alkyl,  
 R 4  and R 4 ′, independently of one another, are unsubstituted or substituted alkyl  
 and wherein at least one of the substituent pairs R 1 /R 1 ′, R 2 /R 2 ′, R 3 /R 3 ′ and/or R 4 /R 4 ′ is non-identical.  
 
     
     
         18 . A solid dye preparation comprising at least 95% by weight of a dye of the formula (I) according to    claim 1   .  
     
     
         19 . A process for preparing dyes according to    claim 17   , wherein a substituted aniline is reacted with a dihalogenoalkylene  
                   
       wherein 
 n is from 2 to 6, X is halogen, in particular Br or Cl, and the other substituents are as defined above,  
 or a substituted aniline is reacted with an N-(halogenoalkyl)aniline (Eq. 2), for example in a solvent or in bulk in the presence of a base, followed by a Vilsmeier formulation (preferably by reacting with POCl 3  and dimethylformamide, followed by hydrolysis) followed by condensation with a reactive methylene compound, preferably malononitrile.  
 
     
     
         20 . Copolymer from the group consisting of styrene-acrylonitrile copolymers (SAN) and acrylonitrile-butadiene-styrene copolymers (ABS), dyed with at least one dye of the formula (I) according to    claim 1   .