Aqueous polyisocyanate-lignin adhesive

Claim 2

An aqueous polyisocyanate-lignin adhesive comprising an aqueous solution of lignin solids derived from the chemical pulping of lignocellulose and an adhesive-forming quantity of organic polyisocyanate polymer having a molecular weight of from 200 to 10,000, the water being used in amount sufficient to establish a working adhesive viscosity.

Claim 3

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.

Claim 4

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.

Claim 5

The adhesive of claim 2 wherein the polyisocyanate has a molecular weight of from about 300 to about 2,000 and the component use is in the following proportions, expressed in parts by weight: ______________________________________ Organic polyisocyanate 50-80 Lignin solids in aqueous solution 20-50 Water 20-500 ______________________________________

Claim 6

The adhesive of claim 2 wherein the lignin comprises calcium base sulfite waste liquor.

Claim 7

The adhesive of claim 2 wherein the lignin comprises ammonium base sulfite waste liquor.

Claim 8

The adhesive of claim 2 wherein the lignin comprises sodium base sulfite waste liquor.

Claim 9

The adhesive of claim 2 wherein the lignin comprises kraft waste liquor.

Claim 10

The adhesive of claim 2 wherein the lignin solids in aqueous solution comprises chlorinated kraft waste liquor.

Claim 11

The adhesive of claim 2 wherein the lignin solids in aqueous solution comprises brominated sulfite waste liquor.

Claim 12

The adhesive of claim 2 wherein the organic polyisocyanate comprises polymeric polymethylene polyphenyl isocyanate.

Claim 13

The adhesive of claim 2 wherein the organic polyisocyanate comprises polymeric diphenylmethane diisocyanate.

Claim 14

The adhesive of claim 2 wherein the organic polyisocyanate comprises polymeric toluene diisocyanate and a chain builder therefor.

Claim 15

The adhesive of claim 2 wherein the organic polyisocyanate comprises polymeric triphenylmethane triisocyanate.

Claim 16

The adhesive of claim 2 including as a co-reactant formaldehyde in the ratio of from 3 to 1 to 6 to 1 parts by weight organic polyisocyanate to formaldehyde.

Claim 17

The adhesive of claim 2 wherein the organic polyisocyanate comprises the reaction product of an organic isocyanate and a polyhydroxy glycol used in predetermined amount sufficient to produce a reactive polyisocyanate having the said molecular weight.

Claim 18

The adhesive of claim 15 wherein the glycol comprises polyethylene glycol having a molecular weight of up to 6000.

Claim 19

The adhesive of claim 15 wherein the glycol comprises polypropylene glycol having a molecular weight of up to 6000.

Claim 20

The adhesive of claim 15 wherein the glycol comprises propylene glycol partially esterified with adipic acid.

Claim 21

The adhesive of claim 15 wherein the glycol comprises trimethylol propane.

Claim 22

The adhesive of claim 15 wherein the glycol comprises 2,4,6-hexane triol.

Claim 23

The adhesive of claim 15 wherein the isocyanate comprises toluene diisocyanate and the glycol comprises polypropylene glycol.

Claim 24

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.

Claim 25

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.

Claim 26

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.

Claim 27

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.

Claim 28

The wood composition board of claim 23 wherein the adhesive has a composition as follows: ______________________________________ Organic polyisocyanate having a molecular weight from 200 to 10,000 50-80 Lignin solids in aqueous solution 20-50 Water 20-500 ______________________________________

Claim 29

The composition board of claim 24 wherein the lignin solids in aqueous solution comprises calcium base sulfite waste liquor.

Claim 30

The composition board of claim 24 wherein the lignin solids in aqueous solution comprises sodium base sulfite waste liquor.

Claim 31

The composition board of claim 24 wherein the lignin solids in aqueous solution comprises ammonium base waste liquor.

Claim 32

The composition board of claim 24 wherein the lignin solids in aqueous solution comprises Kraft waste liquor.

Claim 33

The wood composition board of claim 24 wherein the organic polyisocyanate comprises polymethylene polyphenylisocyanate.