Aqueous polyisocyanate-lignin adhesive

A water-tolerant, sprayable, adhesive for wood products comprising, in parts by weight:

• ______________________________________ Organic polyisocyanate having a molecular weight from 200 to 10,000 20-95 Lignin solids in aqueous solution 5-80 Water 5-1000 ______________________________________
• the lignin solids being the product of the chemical pulping of lignocellulose, the water being expressed as the total water present, being the sum of water added and the water content of the lignin solution.

As a new article of manufacture, the glued product comprising pieces of wood bonded together with an adhesive comprising an aqueous solution of lignin derived from the chemical pulping of lignocellulose and an adhesive-forming quantity of organic polyisocyanate polymer having a molecular weight of from about 200 to about 10,000, the water being used in amount sufficient to establish a working adhesive viscosity.

As a new article of manufacture, the wood composition board comprising a hot-consolidated mat comprising small pieces of wood glued together with from 1 to 10% by weight of the mat of an adhesive comprising, in parts by weight:

• ______________________________________ Organic polyisocyanate having a molecular weight from 200 to 10,000 20-95 Lignin solids in aqueous solution 5-80 Water 5-1000 ______________________________________
• the lignin solids being the product of the chemical pulping of lignocellulose, the water being expressed as the total water present, being the sum of the water added and the water content of the lignin solids solution.