To provide an adhesive comprising an acrylic resin (1), an acrylic resin (2), a silicone oligomer (3) and a crosslinking agent (4): wherein the acrylic resin (1) comprises a structural unit (a) derived from a monomer (A) and a structural unit (b) derived from a monomer (B) and has a weight-average molecular weight of 1,000,000 to 2,000,000, wherein the (A) is a (meth)acrylic ester represented by the formula (A) ##STR00001## (wherein R.sub.1 represents hydrogen atom or methyl group, and R.sub.2 represents alkyl or aralkyl groups having 1 to 14 carbon atoms wherein hydrogen atom(s) of the R.sub.2 may be substituted with alkoxy group having 1 to 10 carbon atoms), and the (B) is at least any one of a (B-1) and a (B-2) wherein the (B-1) is a monomer comprising carboxyl group and one olefinic double bond, and the (B-2) is a monomer comprising at least one polar functional group selected from the group consisted of hydroxyl group, amide group, amino group, epoxy group, oxetanyl group, aldehyde group and isocyanate group and an olefinic double bond; the acrylicresin (2) comprises the structural unit (a) and the structural unit (b) and has a weight-average molecular weight of 50,00 to 500,000; and the silicone oligomer (3) has 2 to 100 structural units (s) derived from a compound (s) represented by ##STR00002## (wherein R.sub.3 and R.sub.4 represent alkyl group or phenyl group, X and Y represent hydrogen atom, optionally substituted alkyl group, optionally substituted phenyl group, optionally substituted alkoxy group, optionally substituted phenoxy group, optionally substituted aralkyl group, optionally substituted aralkyloxy group, vinyl group, vinyloxy group, 1,2-epoxycyclohexyl group, 1,2-epoxycyclohexyloxy group, styryl group, styryloxy group, methacryloyloxy group, amino group, ureido group, mercapto group or isocyanate group).