摘要:
Provided is a polyurethane for printing ink binders excellent in solubility in a solvent having a low solvency, low viscosity and adhesion to films, and a method for producing the same.A method for producing urethane for printing ink binders, wherein a polyurethane is obtained by reacting a polyol (A), a polyisocyanate compound (B) and a chain extender (C), and the polyol (A) contains a polyesterether polyol (A1) which is obtained by copolymerizing a polycarboxylic acid anhydride (b) and an alkylene oxide (c) to an initiator (a) in the presence of a catalyst (x).
摘要:
An object of the invention is to provide a process for urethane resin production in which the molecular weight of the urethane resin can be easily controlled regardless of the kind of polyisocyanate compound and which can yield a urethane resin for use as a removable pressure-sensitive adhesive usable in extensive applications ranging from a strong-tack region to a slight-tack region. The process for urethane resin production of the invention is a process for producing a urethane resin which comprises reacting a polyol with a first polyisocyanate compound in such a proportion that isocyanate groups are present in excess to thereby obtain an isocyanate-group-terminated prepolymer, subsequently reacting the isocyanate-group-terminated prepolymer with a chain extender, and further reacting the resultant polymer with a chain terminator, wherein the chain extender comprises a polyfunctional compound (X) having three or more functional groups reactive with an isocyanate group, wherein two of the functional groups of the polyfunctional compound (X) are primary hydroxyl groups and the remaining functional group(s) is secondary hydroxyl or tertiary hydroxyl group(s).
摘要:
A process for producing a urethane resin having a low viscosity and usable as a wide range of pressure-sensitive adhesives ranging from a strong-tack region to a slight-tack region, and a pressure-sensitive adhesive are provided. The process for producing a urethane resin comprises reacting a polyol with a polyisocyanate compound in such a proportion that isocyanate groups are in excess to thereby obtain an isocyanate-group-terminated prepolymer, thereafter reacting the isocyanate-group-terminated prepolymer with a chain extender, and reacting the resultant polymer with a chain terminator, wherein the chain extender has three or more functional groups reactive with an isocyanate group, wherein one of the functional groups is a primary amino group or a secondary amino group, another is a primary hydroxyl group, and the remaining functional group(s) are a secondary hydroxyl group or a tertiary hydroxyl group. The pressure-sensitive adhesive comprises the urethane resin obtained.
摘要:
A hot melt adhesive composition employing a thermoplastic polyurethane, which has a high adhesive strength even under bonding conditions of low temperature and short time or even to nylon cloth, and which has a favorable adhesive strength in a wide temperature range of from room temperature to low temperature. A hot melt adhesive composition comprising a thermoplastic polyurethane (A) having a flow initiation temperature of from 80 to 150° C. and a phenolic hydroxy group-containing compound (B) having phenolic hydroxy groups and having a molecular weight of at least 1,000.