Laminating adhesives based on primary hydroxyl-containing curatives
OwnerJames B. Simonsinventor
Life of this patent
Estimating the term…
Abstract
A curative containing two or more primary hydroxyl groups per molecule and one or more moieties derived from a secondary hydroxyl-containing polyol such as polypropylene glycol is prepared in a multistage process wherein the secondary hydroxyl-containing polyol is end-capped with an excess of a reactant such as a polybasic acid and the resulting functionalized intermediate is then reacted with a polyol such as glycerin or diethylene glycol containing primary hydroxyl groups. Such curatives may be used in combination with isocyanate-functionalized polyurethane prepolymers to provide two component adhesives useful for laminating thin films and/or foils.
Claims20
A two component laminating adhesive comprising Component A and Component B, wherein Component A comprises at least one isocyanate-functionalized compound and Component B comprises a curative containing at least about two primary hydroxyl groups per molecule, said curative having been obtained by a process comprising reacting a first polyol containing predominately secondary hydroxyl groups with a stoichiometric excess of a reactant selected from the group consisting of polybasic acids, polybasic acid anhydrides, polybasic acid esters, and polyisocyanates to form an intermediate containing at least about two terminal functional groups per molecule selected from the group consisting of isocyanate, carboxylic acid and carboxylic acid ester and reacting said intermediate with a stoichiometric excess of a second polyol containing predominately primary hydroxyl groups.
A two component laminating adhesive comprising Component A and Component B, wherein Component A comprises at least one isocyanate-functionalized compound and Component B comprises a curative having the structure:
- Y—O—C(═O)—Z—C(═O)—O—CH(CH˜)—CH˜—O—(C˜H—O)˜—CH˜—CH(CH˜)—O—C(˜O)—Z˜—C(˜O)—O—Y˜
- wherein Y and Y′ are the same or different and are selected from the group consisting of HO—CH2—CH(OH)—CH2— and HO—(CH2—CH2—O—), —CH2—CH2—, Z and Z′ are the same or different and are selected from the group consisting of —C6H4—, —(CH2),,— and combinations thereof, p is 0 or an integer of 1 to 3, o is an integer of from 2 to 10, and n is 0 or an integer of from 1 to 100.
(canceled)
A process for making a curative containing at least about two primary hydroxyl groups per molecule comprising reacting a first polyol containing predominately secondary hydroxyl groups with a stoichiometric excess of a reactant selected from the group consisting of polybasic acids, polybasic acid anhydrides, polybasic acid esters, and polyisocyanates to form an intermediate containing at least about two functional groups per molecule selected from the group consisting of isocyanate, carboxylic acid and carboxylic acid ester and reacting said intermediate with a stoichiometric excess of a second polyol containing predominately primary hydroxyl groups.
Dependencies are inferred from the claim text.