Pressure-sensitive adhesive contg. acrylate] ester] copolymer mixt. - including alkyl acrylate] ethyl acrylate] N-methylol methacrylamide (meth)acrylic] acid copolymer with low tack and high adhesion and cohesion

摘要

Pressure-sensitive polyacrylate ester adhesive (I) contains: 0-30 (wt.)% copolymer (A) of 2-8 C alkyl acrylate (II) with 1-10% acrylic acid (III); 20-70% copolymer (B) of 4-8 C alkyl acrylate with 20-60% ethyl acrylate, 2-8% self-cross-linking N-methylolmethacrylamide and 1-10% (meth)acrylic acid; 20-70% copolymer (C) of (II) with 10-60% vinyl acetate (IV) and 1-10% (III); and 0-40% copolymer (D) of (II) with 10-40% (IV) acetate, 1-10% acrylonitrile (IX) and 1-10% (III); and opt. usual additives. The Fikentscher K values are (A) 70-100, (B) 80-120, (C) 40-90, (D) 50-90 (in THF, DIN 51562). Pref. the K values are (A) 80-100, (B) 90-110, (C) 50-80, (D) 60-80. The acrylate ester is n-butyl acrylate (IIA) and/or 2-ethylhexyl acrylate (IIB). The copolymers may also contain other monomers, pref. methacrylate esters, methacrylonitrile, methacrylic acid, hydroxyethyl acrylate and styrene, pref. in amts. of 0.5-35, esp. 1-20%. USE/ADVANTAGE - (I) is used for producing self-adhesive coatings on one or both sides of substrate sheets, esp. PVC films contg. monomeric or polymeric plasticiser (claimed), e.g. for adhesive tape and plotter coloured film. The instant tack is slight, which allows correction of freshly bonded film, whilst the final adhesion and cohesion are good.