Blocked polyisocyanate and uses thereof
First Claim
1. A blocked polyisocyanate, which is substantially the same product as obtained by blocking 50 to 100% by mole of the terminal isocyanate groups of a non-blocked polyisocyanate with a thermally dissociative blocking agent, said non-blocked polyisocyanate being obtained by reacting at least one diisocyanate selected from the group consisting of an aliphatic diisocyanate and an alicyclic diisocyanate with a polyhydroxy compound having an average number of hydroxyl groups of from 4.5 to 10, and removing substantially all unreacted diisocyanate monomers,said non-blocked polyisocyanate having the following characteristics (a) to (d):
- (a) a cyclic isocyanate trimer content of 10% or less, in terms of a ratio of the area of a peak ascribed to a cyclic isocyanate trimer, relative to the total area of all peaks ascribed to said non-blocked polyisocyanate in a gel permeation chromatogram thereof;
(b) an average number of terminal isocyanate groups of from 5 to 20;
(c) a number average molecular weight of from 1,200 to 10,000 as measured by gel permeation chromatography (GPC); and
(d) a terminal isocyanate group content of from 5 to 20% by weight,said blocked polyisocyanate having the following characteristics (e) to (g);
(e) an average number of blocked terminal isocyanate groups of from 5 to 20;
(f) a blocked terminal isocyanate group content of from 2 to 20% by weight; and
(g) a number average molecular weight of from 1,500 to 15,000 as measured by GPC.
1 Assignment
0 Petitions
Accused Products
Abstract
Disclosed is a novel blocked polyisocyanate obtained by blocking the terminal isocyanate groups of a non-blocked polyisocyanate with a thermally dissociative blocking agent, wherein the non-blocked polyisocyanate is obtained by reacting at least one diisocyanate selected from the group consisting of an aliphatic diisocyanate and an alicyclic diisocyanate with a polyhydroxy compound having an average number of hydroxyl groups as many as 4.5 to 10, and removing substantially all unreacted diisocyanate monomers. A coating composition comprising the blocked polyisocyanate of the present invention as a curing agent and a polyol as a main agent not only has excellent curability even under low temperature conditions, but is also capable of forming a coating which has excellent impact resistance. The blocked polyisocyanate of the present invention has excellent miscibility with a plasticizer for the blocked polyisocyanate, so that, an adhesive property-imparting composition comprising the blocked polyisocyanate and a plasticizer and/or a solvent can be combined with a plastisol to prepare a plastisol composition having excellent adhesive properties even under low temperature conditions.
-
Citations
11 Claims
-
1. A blocked polyisocyanate, which is substantially the same product as obtained by blocking 50 to 100% by mole of the terminal isocyanate groups of a non-blocked polyisocyanate with a thermally dissociative blocking agent, said non-blocked polyisocyanate being obtained by reacting at least one diisocyanate selected from the group consisting of an aliphatic diisocyanate and an alicyclic diisocyanate with a polyhydroxy compound having an average number of hydroxyl groups of from 4.5 to 10, and removing substantially all unreacted diisocyanate monomers,
said non-blocked polyisocyanate having the following characteristics (a) to (d): -
(a) a cyclic isocyanate trimer content of 10% or less, in terms of a ratio of the area of a peak ascribed to a cyclic isocyanate trimer, relative to the total area of all peaks ascribed to said non-blocked polyisocyanate in a gel permeation chromatogram thereof; (b) an average number of terminal isocyanate groups of from 5 to 20; (c) a number average molecular weight of from 1,200 to 10,000 as measured by gel permeation chromatography (GPC); and (d) a terminal isocyanate group content of from 5 to 20% by weight, said blocked polyisocyanate having the following characteristics (e) to (g); (e) an average number of blocked terminal isocyanate groups of from 5 to 20; (f) a blocked terminal isocyanate group content of from 2 to 20% by weight; and (g) a number average molecular weight of from 1,500 to 15,000 as measured by GPC. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
Specification