The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 31, 1989
Filed:
Feb. 06, 1987
Hanns I Sachs, Cologne, DE;
Donald R Larimer, Bergisch Gladbach, DE;
Bayer Aktiengesellschaft, Leverkusen, DE;
Abstract
This invention relates to formaldehyde-free, aqueous glue dispersions which contain polyisocyanates. These systems are particularly suitable for gluing veneers and surface materials on wood and wood products. The systems are prepared from polyisocyanates in combination with extenders based on flours and cold water-soluble of hydrolyzed natural starch. In this process, polyisocyanates or aqueous dispersions thereof are added while stirring to aqueous solutions or mixtures of starch and flour. The extender-containing adhesive systems are aqueous glue dispersions having increased service life which in their preferred embodiment contain about 15 to 30% by weight of polyisocyanates, preferably polyphenyl-polymethylene polyisocyanate (PMDI), 10 to 15% by weight of starch which is soluble in cold water and 14 to 25% by weight of (cereal) flour and optionally, other additives and the appropriate quantity of water adding up to 100% by weight. The glue dispersions are easily applied with glue spreading machines and if applied in suitable quantities do not bleed through veneers. The implements used for applying the glues can easily be cleaned by rinsing them with water. The invention is also directed to the use of the glue dispersions for gluing, particularly for gluing veneers or other surface coating materials to wood or wood products.