A pattern article comprising a copolymer having polymerized units derived from a cleavable crosslinking monomer, to which a pattern is imparted by the release of incipient acid from a thermal acid generator or photoacid generator. The selective release of the acid provides a pattern of high crosslink density and low crosslink density as result of the incipient acid cleaving a portion of the crosslinks.

A pattern article comprising a copolymer having polymerized units derived from a cleavable crosslinking monomer, to which a pattern is imparted by the release of incipient acid from a thermal acid generator or photoacid generator. The selective release of the acid provides a pattern of high crosslink density and low crosslink density as result of the incipient acid cleaving a portion of the crosslinks.

Provided is an adhesive composition which is flexible, and exhibits excellent adhesion durability. The adhesive composition comprises (a) a 2-cyanoacrylic acid ester, (b) a polymer having a hydrolyzable silyl group, (c) an elastomer, and (d) an acid catalyst, in which the contents of the components (b), (c), and (d) are from 5 to 200 parts by mass, from 5 to 50 parts by mass, and from 0.0005 to 0.5 parts by mass, respectively, relative to 100 parts by mass of the component (a). Further preferably, the composition contains 0.001 to 5 parts by mass of (e) an onium salt relative to 100 parts by mass of the component (a).

The present invention relates to a pressure-sensitive adhesive composition including a compound having a substituent represented by the general formula (1) described in the specification, in which when each of R.sup.1 and R.sup.2 in the substituent represented by the general formula (1) represents a hydrogen atom, a distance between an oxygen atom of OR.sup.1 and an oxygen atom of OR.sup.2 is 1.31 or more and 4.70 or less, a pressure-sensitive adhesive layer formed of the pressure-sensitive adhesive composition, and a pressure-sensitive adhesive sheet comprising the pressure-sensitive adhesive layer.