Water Vapor-Blocking Adhesive Compound Having Highly Functionalized Poly(meth)acrylate

Abstract

The present invention relates to a curable adhesive compound for encapsulating an electronic or optoelectronic arrangement against permeates, made of the following components: (A) 20 to 99.9 wt % (relative to the total amount of the curable adhesive compound) of a (co)polymer functionalized with epoxy groups and having a weight-average molar mass in the range of at least 5,000 g/mol, based on more than 30 to 100 wt %, preferably 50 to 100 wt %, (relative to the total amount of the monomers on which the epoxide-functionalized (co)polymer is based) of at least one type of (meth)acrylic (co)monomer (a) functionalized with an epoxy group, (B) 0.1 to 5 wt % (relative to the total amount of the curable adhesive compound) of at least one curing agent which can induce, thermally and/or by the application of UV radiation, the curing, in particular the cationic curing, of the (co)polymer (A) under reaction of its epoxy groups, (C) optionally 0 to 79.9 wt % of additional components.

1 . A curable adhesive composition for encapsulation of an electronic or optoelectronic arrangement against permeants, comprising the following components:
 (A) 20% to 99.9% by weight (based on the entirety of the curable adhesive composition) of a (co)polymer functionalized with epoxy groups and having a weight-average molar mass in the region of at least 5000 g/mol, based on more than 30% to 100% by weight, (based on the entirety of the parent monomers of the epoxy-functionalized (co)polymer) of at least one type of (meth)acrylic (co)monomer (a) functionalized with an epoxy group,   (B) 0.1% to 5% by weight (based on the entirety of the curable adhesive composition) of at least one curing agent that can induce the curing of the (co)polymer (A) with reaction of its epoxy groups by thermal means and/or by supply of UV radiation,   (C) optionally 0% to 79.9% by weight of further constituents.   
     
     
         2 . The curable adhesive composition as claimed in  claim 1 , wherein
 the weight-average molar mass of the epoxy-functionalized (co)polymer is at least 10 000 g/mol, and/or at most 200 000 g/mol.   
     
     
         3 . (canceled) 
     
     
         4 . The curable adhesive composition as claimed in  claim 1 ,
 having   pressure-sensitive adhesive properties.   
     
     
         5 . The curable adhesive composition as claimed in  claim 1 , wherein
 cycloaliphatic epoxides are used for one, more than one, or all the (meth)acrylic (co)monomers (a) functionalized with an epoxy group.   
     
     
         6 . The curable adhesive composition as claimed in  claim 5 , wherein
 the cycloaliphatic epoxides are 3,4-epoxycyclohexyl-substituted monomers.   
     
     
         7 . The curable adhesive composition as claimed in  claim 1 , wherein
 comonomers used in the preparation of the functionalized (co)polymer are silicon compounds.   
     
     
         8 . The curable adhesive composition as claimed in  claim 1 , comprising
 thermally activatable curing agents for cationic curing of epoxides in the form of thermally activatable acid formers, and/or   photoinitiators as curing agent, and/or   at least one tackifying resin, and/or   at least one reactive resin that is aliphatic or cycloaliphatic, and/or   one or more additives, and/or   one or more fillers.   
     
     
         9 . The curable adhesive composition as claimed in  claim 8 , wherein
 the thermally activatable curing agents are selected from the group consisting of:   pyridinium salts, ammonium salts, sulfonium salts, and lanthanoid triflates.   
     
     
         10 . (canceled) 
     
     
         11 . The adhesive composition as claimed in  claim 8 ,
 wherein   the photoinitiators absorb UV light above 250 nm and below 350 nm.   
     
     
         12 . (canceled) 
     
     
         13 . (canceled) 
     
     
         14 . (canceled) 
     
     
         15 . The adhesive composition as claimed in  claim 1 ,
 wherein   one or more silanes have been mixed in.   
     
     
         16 . (canceled) 
     
     
         17 . The adhesive composition as claimed in  claim 1 ,
 being transparent in the visible light of the spectrum (wavelength range from about 400 nm to 800 nm) and/or has a transmission (by test F1) of at least 75%.   
     
     
         18 . The adhesive composition as claimed in  claim 1 ,
 showing a haze (by test F2) of not more than 5.0%.   
     
     
         19 . The adhesive composition as claimed in  claim 1 , having a lag time by test B of at least 150 h. 
     
     
         20 . An adhesive tape comprising at least one layer of an adhesive composition as claimed in  claim 1  and a carrier,
 wherein 
 the carrier has a permeation barrier of WVTR<0.1 g/(m 2  d) and OTR<0.1 cm 3 /(m 2  d bar). 
 
     
     
         21 . The adhesive tape as claimed in  claim 20 ,
 wherein   the carrier is a coated polymer film, and/or   the carrier has a layer of a flexible thin glass having a layer thickness of not more than 1 mm.   
     
     
         22 . (canceled) 
     
     
         23 . The adhesive tape as claimed in  claim 21 ,
 wherein   the thin glass is in strip geometry.   
     
     
         24 . A method for encapsulation of an (opto)electronic arrangement, said method comprising a step of applying an adhesive composition or of a single- or double-sided adhesive tape formed with the adhesive composition according to  claim 1  to a substrate. 
     
     
         25 . The method as claimed in  claim 24 ,
 wherein   the adhesive composition and/or the regions of the (opto)electronic arrangement to be encapsulated are heated before, during and/or after the application of the adhesive composition.   
     
     
         26 . The method as claimed in  claim 24 ,
 wherein   the adhesive composition is partly or finally crosslinked after application to the (opto)electronic arrangement.   
     
     
         27 . An electronic arrangement having an electronic structure, and an adhesive composition,
 wherein the (opto)electronic structure has been at least partly encapsulated by the adhesive composition,   and wherein   the adhesive composition is formed according to  claim 1  and is in cured form.