A (meth)acrylic acid copolymer (A) having a weight average molecular weight of 1000 to 1,000,000, and in which when the half-width of the primary scatter peak when measured by small angle X-ray scattering is defined as X, 0.12<X, is used as an adhesive. The (meth)acrylic copolymer (A) is obtained by polymerizing a monomer mixture containing a macromonomer (a) having a number average molecular weight of 500-100,000, and a vinyl monomer (b). The adhesive has sufficient holding force and adhesive force, and the occurrence of adhesive deposit can be prevented when peeled off.

A label assembly including one or more dissolvable thermal direct adhesive labels and methods of assembly and use. According to one embodiment, each label includes a base layer, a thermal direct layer, an adhesive layer, and a barrier layer. The base layer, which has an upper surface and a lower surface, is water-dissolvable and may be made of a water-dissolvable paper. The thermal direct layer is positioned directly over the upper surface of the base layer and functions in the conventional manner to produce markings therein in response to heat. The adhesive layer is water-dissolvable and is positioned below the lower surface of the base layer. The barrier layer, which is positioned directly below the lower surface of the base layer and directly over the adhesive layer, serves to prevent migration of the adhesive layer through the base layer and into contact with the thermal direct layer.

An adhesive composition includes a first acrylic polymer preparable from first components and a second acrylic polymer. The first components comprising i) a branched first alkyl (meth)acrylate having from 4 to 22 carbon atoms, and ii) at least one of acrylic acid and methacrylic acid. The second acrylic polymer is preparable from second components comprising iii) at least one second alkyl (meth)acrylate having from 4 to 22 carbon atoms, iv) a (meth)acrylamide represented by the formula

##STR00001##

wherein R.sup.1 is H or methyl, and R.sup.2 and R.sup.3 each independently represents H or an alkyl group having from 1 to 8 carbon atoms, or taken together R.sup.2 and R.sup.3 may form a divalent alkylene group having from 4 to 6 carbon atoms, and v) at least one high T.sub.g macromer having a terminal free-radically polymerizable unsaturated group, the high T.sub.g macromer having a T.sub.g of at least 45 C. Based on the combined total weight of the at least one first acrylic polymer and the at least one second acrylic polymer, the at least one second acrylic polymer is present at a level of from 5 to 40 percent by weight. Methods of making the adhesive composition are also disclosed.

An adhesive composition includes a first acrylic polymer preparable from first components and a second acrylic polymer. The first components comprising i) a branched first alkyl (meth)acrylate having from 4 to 22 carbon atoms, and ii) at least one of acrylic acid and methacrylic acid. The second acrylic polymer is preparable from second components comprising iii) at least one second alkyl (meth)acrylate having from 4 to 22 carbon atoms, iv) a (meth)acrylamide represented by the formula

##STR00001##

wherein R.sup.1 is H or methyl, and R.sup.2 and R.sup.3 each independently represents H or an alkyl group having from 1 to 8 carbon atoms, or taken together R.sup.2 and R.sup.3 may form a divalent alkylene group having from 4 to 6 carbon atoms, and v) at least one high T.sub.g macromer having a terminal free-radically polymerizable unsaturated group, the high T.sub.g macromer having a T.sub.g of at least 45 C. Based on the combined total weight of the at least one first acrylic polymer and the at least one second acrylic polymer, the at least one second acrylic polymer is present at a level of from 5 to 40 percent by weight. Methods of making the adhesive composition are also disclosed.

The present invention relates to a photocurable adhesive sheet. Provided is a new adhesive sheet that can be photocured even if there are places such as print-concealed sections that are difficult for light to reach, and even if the adhesive sheet has a certain degree of thickness, the entire sheet can be cured.

Proposed is a transparent adhesive sheet formed from an adhesive composition containing: (A) a thermoplastic resin; (B) a crosslinking agent; (C) a photopolymerization initiator that reacts with light having a wavelength of at least 380 to 430 nm; and (D) a wavelength conversion agent that is excited by light having a wavelength shorter than 380 nm and that emits light having a wavelength of 380 to 550 nm. The transparent adhesive sheet is characterized by the adhesive sheet absorbance X at a wavelength of 390 nm and the adhesive sheet thickness Y satisfying relational formula (1).

0.5X/Y12Formula (1):

An adhesive composition includes a first acrylic polymer preparable from first components and a second acrylic polymer. The first components comprising i) a branched first alkyl (meth)acrylate having from 4 to 22 carbon atoms, and ii) at least one of acrylic acid and methacrylic acid. The second acrylic polymer is preparable from second components comprising iii) at least one second alkyl (meth)acrylate having from 4 to 22 carbon atoms, iv) a (meth)acrylamide represented by the formula ##STR00001##
wherein R.sup.1 is H or methyl, and R.sup.2 and R.sup.3 each independently represents H or an alkyl group having from 1 to 8 carbon atoms, or taken together R.sup.2 and R.sup.3 may form a divalent alkylene group having from 4 to 6 carbon atoms, and v) at least one high T.sub.g macromer having a terminal free-radically polymerizable unsaturated group, the high T.sub.g macromer having a T.sub.g of at least 45 C. Based on the combined total weight of the at least one first acrylic polymer and the at least one second acrylic polymer, the at least one second acrylic polymer is present at a level of from 5 to 40 percent by weight. Methods of making the adhesive composition are also disclosed.

An adhesive composition includes a first acrylic polymer preparable from first components and a second acrylic polymer. The first components comprising i) a branched first alkyl (meth)acrylate having from 4 to 22 carbon atoms, and ii) at least one of acrylic acid and methacrylic acid. The second acrylic polymer is preparable from second components comprising iii) at least one second alkyl (meth)acrylate having from 4 to 22 carbon atoms, iv) a (meth)acrylamide represented by the formula ##STR00001##
wherein R.sup.1 is H or methyl, and R.sup.2 and R.sup.3 each independently represents H or an alkyl group having from 1 to 8 carbon atoms, or taken together R.sup.2 and R.sup.3 may form a divalent alkylene group having from 4 to 6 carbon atoms, and v) at least one high T.sub.g macromer having a terminal free-radically polymerizable unsaturated group, the high T.sub.g macromer having a T.sub.g of at least 45 C. Based on the combined total weight of the at least one first acrylic polymer and the at least one second acrylic polymer, the at least one second acrylic polymer is present at a level of from 5 to 40 percent by weight. Methods of making the adhesive composition are also disclosed.

Multigraft copolymers having various structures, e.g., comb and centipede structures, can be prepared from emulsion copolymerization of monomers and macromonomers. The emulsion copolymerization can be initiated by a thermally activated radical initiator or a redox initiation system. The multigraft copolymers can have high molecular weight and/or a large number of branch points. Elastomer or adhesive compositions of the copolymers can be prepared. Also described are poly(n-alkyl acrylate-graft-styrene) multigraft copolymers.

An adhesive composition includes a first acrylic polymer preparable from first components and a second acrylic polymer. The first components comprising i) a branched first alkyl (meth)acrylate having from 4 to 22 carbon atoms, and ii) at least one of acrylic acid and methacrylic acid. The second acrylic polymer is preparable from second components comprising iii) at least one second alkyl (meth)acrylate having from 4 to 22 carbon atoms, iv) a (meth)acrylamide represented by the formula

##STR00001##

wherein R.sup.1 is H or methyl, and R.sup.2 and R.sup.3 each independently represents H or an alkyl group having from 1 to 8 carbon atoms, or taken together R.sup.2 and R.sup.3 may form a divalent alkylene group having from 4 to 6 carbon atoms, and v) at least one high T.sub.g macromer having a terminal free-radically polymerizable unsaturated group, the high T.sub.g macromer having a T.sub.g of at least 45 C. Based on the combined total weight of the at least one first acrylic polymer and the at least one second acrylic polymer, the at least one second acrylic polymer is present at a level of from 5 to 40 percent by weight. Methods of making the adhesive composition are also disclosed.

An adhesive composition includes a first acrylic polymer preparable from first components and a second acrylic polymer. The first components comprising i) a branched first alkyl (meth)acrylate having from 4 to 22 carbon atoms, and ii) at least one of acrylic acid and methacrylic acid. The second acrylic polymer is preparable from second components comprising iii) at least one second alkyl (meth)acrylate having from 4 to 22 carbon atoms, iv) a (meth)acrylamide represented by the formula

##STR00001##

wherein R.sup.1 is H or methyl, and R.sup.2 and R.sup.3 each independently represents H or an alkyl group having from 1 to 8 carbon atoms, or taken together R.sup.2 and R.sup.3 may form a divalent alkylene group having from 4 to 6 carbon atoms, and v) at least one high T.sub.g macromer having a terminal free-radically polymerizable unsaturated group, the high T.sub.g macromer having a T.sub.g of at least 45 C. Based on the combined total weight of the at least one first acrylic polymer and the at least one second acrylic polymer, the at least one second acrylic polymer is present at a level of from 5 to 40 percent by weight. Methods of making the adhesive composition are also disclosed.