Abstract: Disclosed is a semicarbazide derivative represented by formula (1) or a terminal-blocked form thereof: wherein R1 represents a terminal isocyanate group-free polyisocyanate residue or a terminal isocyanate group-free triisocyanate residue; R2 represents an alkylene group, a cycloalkylene group, or an arylene group; each R3 independently represents a hydrogen atom or an alkyl group; n is zero or 1; and each of and m is independently zero or a positive integer, provided l that l and m satisfy the relationship 3≦(l+m)≦20. Also disclosed is (&dgr;) a composition comprising (&agr;) at least one member selected from the group consisting of the semicarbazide derivative and a terminal-blocked form thereof and (&bgr;) at least one member selected from the group consisting of a hydrophilic group-containing compound and a terminal-blocked form thereof.

Abstract: A method for producing a hydroxyl-terminated (meth) acrylic polymer which comprises converting a halogen atom in a terminal structure of the general formula (1) —CH2—C(R1)(CO2R2)(X)  (1) wherein R1 is hydrogen or methyl, R2 is alkyl containing 1 to 20 carbon atoms, aryl containing 6 to 20 carbon atoms or aralkyl containing 7 to 20 carbon atoms, and X is chlorine, bromine or iodine, of a (meth)acrylic polymer obtained by polymerizing a (meth)acrylic monomer using an organic halide or a halogenated sulfonyl compound as an initiator and, as a catalyst, a metal complex with a central metal selected from the elements belonging to the groups 8, 9, 10 and 11 in the periodic table, into a hydroxyl-containing substituent. The present invention can provide, in an easy and simple manner, a (meth)acrylic polymer which is hydroxyl-terminated at both ends in a high proportion and which has been difficult to produce in the prior art. It can give a cured product with good curing characteristics.

Abstract: An absorbing agent has a diffusing absorbency under pressure of not less than 25 g/g when 60 minutes elapsed after absorption is started, and a water-soluble content is above 0 percent by weight and not more than 7 percent by weight. The absorbing agent is prepared by surface-crosslinking a precursor of the absorbing agent obtained by performing an aqueous solution polymerization of a hydrophilic unsaturated monomer having not less than 50 mole percent neutralized acrylic acid as a main component using a specific crosslinking agent having a main component composed of an ester compound of a specific polyhydroxy alcohol and an unsatuated carboxylic acid, and a high-boiling component having at least two alcohol structures in a molecule as a specific ratio.