US5140086A — Isocyanate modified cellulose products and method…

Claim 1

Independent Claim 107 words

A method for making a polyurea-cellulose composite which comprises: impregnating a substantially delignified cellulosic material with an isocyanate resin comprising at least one polyisocyanate compound and a miscible organic solvent therefor, where the solvent comprises up to about 20% w/w of the polyisocyanate and the isocyanate resin constitutes about 8% to about 20% w/w of the cellulosic material so as to form a polyisocyanate-impregnated cellulosic material; and curing the polyisocyanate-impregnated cellulosic material at a temperature within a range of about 105° to about 245° C. for a time not exceeding about 5 minutes and at a pressure within a range of about 130 to about 1200 psig.

Claim 2

Independent Claim 107 words

A method for making a polyurea-cellulose composite which comprises: impregnating a substantially delignified cellulosic material with an isocyanate resin comprising at least one polyisocyanate compound and a miscible organic solvent therefor, where the solvent comprises up to about 20% w/w of the polyisocyanate and the isocyanate resin constitutes about 8% to about 20% w/w of the cellulosic material so as to form a polyisocyanate-impregnated cellulosic material; and curing the polyisocyanate-impregnated cellulosic material at a temperature within a range of about 105° to about 245° C. for a time not exceeding about 5 minutes and at a pressure within a range of about 130 to about 1200 psig.

Claim 3

Dependent Claim 77 words

The method of claim 1 in which the cellulosic material is in a sheet form having first and second sheet surfaces substantially parallel to each other and a Z or thickness dimension extending in a direction between the first and second sheet surfaces perpendicular to the first and second sheet surfaces, and wherein the isocyanate resin is substantially uniformly distributed throughout the Z or thickness dimension of the sheet after impregnating the sheet with the isocyanate resin.

Claim 4

Dependent Claim 25 words

The method of claim 1 in which the polyisocyanate is selected from the group consisting of lower aliphatic, alicyclic, and aromatic polyisocyanates, and mixtures thereof.

Claim 5

Dependent Claim 12 words

The method of claim 3 in which the polyisocyanate is poly(diphenylmethane diisocyanate).

Claim 6

Dependent Claim 29 words

The method of claim 1 in which the solvent is selected from the group consisting of alkylene carbonates, aromatics, halogenated aromatics, nitroaromatics, alkylated aromatics, ethers, ketones, and alkyl acetates.

Claim 7

Dependent Claim 27 words

The method of claim 1 in which the cellulosic material has a moisture content not exceeding about 10% w/w relative to the mass of the cellulosic material.

Claim 8

Dependent Claim 13 words

The method of claim 1 in which the isocyanate resin includes a catalyst.

Claim 9

Dependent Claim 33 words

The method of claim 7 in which the catalyst is present in the isocyanate resin in a concentration within a range of about 0.1 to about 0.5% w/w relative to the isocyanate resin.

Claim 10

Dependent Claim 24 words

The method of claim 7 in which the catalyst is selected from the group consisting of aliphatic tertiary amines, aliphatic metal complexes, and acetylacetonates.

Claim 11

Dependent Claim 22 words

The method of claim 9 in which the catalyst is selected from the group consisting of diazobicyclooctane, tin octoate, and dibutyltin dilaurate.

Claim 12

Dependent Claim 36 words

The method of claim 1 in which the cellulosic material is selected from the group consisting of pulped cellulose fibers; chemical pulps; thermomechanical pulps; bleached and unbleached paper and paper-like materials, non-woven mats, sheets, and felts.

Claim 13

Dependent Claim 22 words

The method of claim 1 in which the solvent comprises from about 5% w/w to about 20% w/w relative to the polyisocyanate.

Claim 14

Dependent Claim 31 words

The method of claim 12 in which the isocyanate resin includes a catalyst in a concentration within a range of about 0.1% to about 0.5% w/w relative to the isocyanate resin.

Claim 15

Dependent Claim 10 words

A polyurea-cellulose composite made by the method of claim 1.

Claim 16

Independent Claim 140 words

A method for making a laminated polyurea-cellulose composite material comprising the steps: individually impregnating each of plural sheets of substantially delignified cellulosic material with an isocyanate resin comprising at least one polyisocyanate compound, a miscible organic solvent therefor, and a catalyst, wherein the solvent comprises up to about 20% w/w of the polyisocyanate and the resin constitutes about 8 to about 20% w/w of the cellulosic material so as to form plural polyisocyanate-impregnated cellulosic lamina; plying at least two of the polyisocyanate-impregnated cellulosic lamina together so as to form a laminar stack of said polyisocyanate-impregnated cellulose lamina; and curing the stack of plied lamina at a temperature in a range of about 105° C. to about 245° C. for a time not exceeding about 5 minutes and at a pressure within a range of about 130 to about 1200 psig.

Claim 17

Independent Claim 140 words

A method for making a laminated polyurea-cellulose composite material comprising the steps: individually impregnating each of plural sheets of substantially delignified cellulosic material with an isocyanate resin comprising at least one polyisocyanate compound, a miscible organic solvent therefor, and a catalyst, wherein the solvent comprises up to about 20% w/w of the polyisocyanate and the resin constitutes about 8 to about 20% w/w of the cellulosic material so as to form plural polyisocyanate-impregnated cellulosic lamina; plying at least two of the polyisocyanate-impregnated cellulosic lamina together so as to form a laminar stack of said polyisocyanate-impregnated cellulose lamina; and curing the stack of plied lamina at a temperature in a range of about 105° C. to about 245° C. for a time not exceeding about 5 minutes and at a pressure within a range of about 130 to about 1200 psig.

Claim 18

Dependent Claim 22 words

The method of claim 15 in which the polyisocyanate-impregnated cellulosic material is plied on at least one face of a rigid substrate.

Claim 19

Dependent Claim 25 words

The method of claim 16 in which the substrate is selected from the group consisting of wood, wood veneer, reconstituted wood products, and wood-containing composites.

Claim 20

Dependent Claim 39 words

The method of claim 15 in which the cellulosic material is selected from the group consisting of pulped cellulose fibers; chemical pulps; thermomechanical pulps; recycled pulp fiber; bleached and unbleached paper and paper-like materials, non-woven mats, sheets, and felts.

Claim 21

Dependent Claim 25 words

The method of claim 15 in which the polyisocyanate is selected from the group consisting of lower aliphatic, alicyclic, and aromatic polyisocyanates, and mixtures thereof.

Claim 22

Dependent Claim 12 words

The method of claim 19 in which the polyisocyanate is poly(diphenylmethane diisocyanate).

Claim 23

Dependent Claim 29 words

The method of claim 15 in which the solvent is selected from the group consisting of alkylene carbonates, aromatics, halogenated aromatics, nitroaromatics, alkylated aromatics, ethers, ketones, and alkyl acetates.

Claim 24

Dependent Claim 12 words

The method of claim 21 in which the solvent is propylene carbonate.

Claim 25

Dependent Claim 30 words

The method of claim 15 in which the catalyst is present in the isocyanate resin at a concentration of about 0.1 to about 0.5% w/w relative to the isocyanate resin.

Claim 26

Dependent Claim 25 words

The method of claim 23 in which the catalyst is selected from the group consisting of aliphatic tertiary amines, aliphatic metal complexes, and acetyl acetonates.

Claim 27

Dependent Claim 22 words

The method of claim 24 in which the catalyst is selected from the group consisting of diazobicyclooctane, tin octoate, and dibutyltin dilaurate.

Claim 28

Dependent Claim 28 words

The method of claim 15 in which the cellulosic material has a moisture content not exceeding about 7 percent w/w relative to the mass of the cellulosic material.

Claim 29

Dependent Claim 11 words

A laminated polyurea-cellulose composite made by the method of claim 15.

Claim 30

Independent Claim 112 words

A method for making a polyurea-cellulose composite, comprising the steps: impregnating a substantially delignified cellulosic material with a resin comprising an isocyanate compound and propylene carbonate, wherein the propylene carbonate is present in the resin at a concentration of up to about 20% w/w relative to the polyisocyanate and the resin constitutes about 8% to about 20% w/w of the cellulosic material, so as to form a polyisocyanate-impregnated cellulosic material; and curing the polyisocyanate-impregnated cellulosic material at a temperature within a range of about 105° C. to about 245° C. for a time not exceeding about 5 minutes and at a pressure within a range of about 130 to about 1200 psig.

Claim 31

Independent Claim 112 words

A method for making a polyurea-cellulose composite, comprising the steps: impregnating a substantially delignified cellulosic material with a resin comprising an isocyanate compound and propylene carbonate, wherein the propylene carbonate is present in the resin at a concentration of up to about 20% w/w relative to the polyisocyanate and the resin constitutes about 8% to about 20% w/w of the cellulosic material, so as to form a polyisocyanate-impregnated cellulosic material; and curing the polyisocyanate-impregnated cellulosic material at a temperature within a range of about 105° C. to about 245° C. for a time not exceeding about 5 minutes and at a pressure within a range of about 130 to about 1200 psig.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1995-08-18	1996-02-17	1996-08-18	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1999-08-18	2000-02-17	2000-08-18	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2003-08-18	2004-02-17	2004-08-18	$7700.00	Window Closed / Lapsed

Isocyanate modified cellulose products and method for their manufacture

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