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US4183997A Expired / Lapsed US ⏱️ 0.0 years remaining

Bonding of solid lignocellulosic material

Assignee: CARBOCOL Inc USA A CORP OF OREGON
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Filing: 1977-10-04
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Granted: 1980-01-15
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Expires: 1997-10-04
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Abstract

Abstract Solid lignocellulosic material is bonded together by heating and pressing at a natural wood, pH by reacting sugars, starches or both in the presence of a catalyst capable of catalyzing transformation of the sugars and starches into a solid, insoluble in water, and an alkaline buffering agent if needed, for example to make waterproof plywood or composite products from particulate wood without hydrolytic degradation of the wood.

Inventors

  • 👤 John Stofko

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 20:09
CPC Classifications
C; C09; C09J; C09J103/00; C09J103/02; B; B27; B27D; B27D1/00; B27D1/04; C08; C08L; C08L97/00; C08L97/02; C08L1/00; C08L1/02; C08L2666/00; C08L2666/28; C08L2666/54; C08L3/00; C08L3/02; C08L5/00; C08L5/14; Y; Y10; Y10T; Y10T428/00; Y10T428/25; Y10T428/253; Y10T428/29; Y10T428/2982; Y10T428/2991; Y10T428/31504; Y10T428/31536; Y10T428/31971; Y10T428/31975; Y10T428/31978; Y10T428/31982; Y10T428/31989

Claims Analysis

Total Claims: 33
Claim 1
Independent Claim 161 words
A method of bonding solid lignocellulosic materials and thereby producing a waterproof bond, which comprises providing on a surface of said solid lignocellulosic material an adhesive-free bonding material consisting essentially of at least one sugar, starch or mixture thereof and an amount sufficient to catalyze transformation of the sugar or starch of a catalyst capable of transformation of the sugar or starch to cause waterproof bonding of adjacent lignocellulosic surfaces by means of the intermediate layer of adhesive-free bonding material therebetween, said catalyst being an alkaline salt or a mixture of an alkaline material and an acidic salt so that said bonding material will not decrease the pH after heating of the solid lignocellulosic material to below about 3.5, and pressing surfaces of the lignocellulosic material together at an elevated temperature and for a time sufficient to effect said bonding by said transformation reactions of the carbohydrate, and wherein the time, temperature and pressure are sufficient to produce a waterproof bond.
Claim 2
Independent Claim 161 words
A method of bonding solid lignocellulosic materials and thereby producing a waterproof bond, which comprises providing on a surface of said solid lignocellulosic material an adhesive-free bonding material consisting essentially of at least one sugar, starch or mixture thereof and an amount sufficient to catalyze transformation of the sugar or starch of a catalyst capable of transformation of the sugar or starch to cause waterproof bonding of adjacent lignocellulosic surfaces by means of the intermediate layer of adhesive-free bonding material therebetween, said catalyst being an alkaline salt or a mixture of an alkaline material and an acidic salt so that said bonding material will not decrease the pH after heating of the solid lignocellulosic material to below about 3.5, and pressing surfaces of the lignocellulosic material together at an elevated temperature and for a time sufficient to effect said bonding by said transformation reactions of the carbohydrate, and wherein the time, temperature and pressure are sufficient to produce a waterproof bond.
Claim 3
Dependent Claim 27 words
A method according to claim 1, in which the carbohydrate is applied and is selected from disaccharides, monosaccharides, molasses and starch obtained from wheat or corn flour.
Claim 4
Dependent Claim 22 words
A method according to claim 1, in which the adhesive-free bonding composition contains at least one sugar and at least one starch.
Claim 5
Dependent Claim 20 words
A method according to claim 3, in which the adhesive-free bonding material contains substantially equal weights of sugar and starch.
Claim 6
Dependent Claim 32 words
A method according to claim 1, in which the amount of catalyst present is from 1 to 50% by weight of the amount of sugar and starch in the adhesive-free bonding material.
Claim 7
Dependent Claim 25 words
A method according to claim 1, in which the adhesive-free bonding material contains a liquid carrier which does not react with the sugar or starch.
Claim 8
Dependent Claim 17 words
A method according to claim 6, in which the liquid carrier is selected from water and ethanol.
Claim 9
Dependent Claim 39 words
A method according to claim 1, in which the adhesive-free bonding material is applied to the surface in an amount to give from 2 to 32 grams of sugar, starch or mixture thereof per 1000 cm 2 of surface.
Claim 10
Dependent Claim 31 words
A method according to claim 1, in which the surfaces are pressed together at a temperature from 140° to 250° C. and a pressure from 5 to 50 kg/cm 2 .
Claim 11
Dependent Claim 33 words
A method according to claim 1, in which the adhesive-free bonding comprises a preformed composition of said sugar, starch or mixture thereof and said catalyst which is heated before application to the surface.
Claim 12
Dependent Claim 30 words
A method according to claim 10, in which the adhesive-free bonding composition is heated at a temperature from 100° to 130° C. for a period from 30 to 120 minutes.
Claim 13
Dependent Claim 23 words
A method according to claim 1, in which the lignocellulosic material is heated after application of the adhesive-free bonding material and before pressing.
Claim 14
Dependent Claim 27 words
A method according to claim 12, in which the lignocellulosic material is heated at a temperature not exceeding 140° C. for a period up to 60 minutes.
Claim 15
Dependent Claim 21 words
A method according to claim 1, in which the lignocellulosic material comprises wood veneers which are laminated together during the pressing.
Claim 16
Dependent Claim 26 words
A method according to claim 14, in which the adhesive-free bonding material is applied to one only of the respective veneer surfaces which are pressed together.
Claim 17
Dependent Claim 15 words
A method according to claim 1, in which the lignocellulosic material comprises particles of wood.
Claim 18
Dependent Claim 83 words
A method according to claim 1, wherein said catalyst is selected from the group consisting of dimethyl formamide with iodine, dimethyl sulfoxide, propylene oxide with ethylene gylcol and zinc chloride, aluminum chloride, ammonium chloride, ammonium nitrate, sodium nitrate, potassium nitrate, ammonium sulfate, potassium tartrate, sodium phosphate, calcium phosphate, sodium sulfate, zinc chloride, diammonium phosphate, superphosphate, and mixtures thereof, said catalyst being in admixture with an alkali to provide a pH before heating in the alkaline range when said catalyst is an acid catalyst.
Claim 19
Dependent Claim 13 words
A method in accordance with claim 17 wherein said catalyst comprises aluminum chloride.
Claim 20
Dependent Claim 38 words
A process in accordance with claim 1 wherein said adhesive-free bonding material further comprises a non-reactive liquid carrier and said pressing is carried out in an unsealed press to permit the escape of vapors of said liquid carrier.
Claim 21
Dependent Claim 17 words
A method in accordance with claim 1 wherein said sugar, starch or mixture thereof comprises strap molasses.
Claim 22
Dependent Claim 17 words
A method in accordance with claim 1 wherein said adhesive-free bonding material further comprises an accelerating reagent.
Claim 23
Dependent Claim 21 words
A method in accordance with claim 21 wherein said accelerator is selected from the group consisting of ethylene glycol and amines.
Claim 24
Dependent Claim 29 words
A method in accordance with claim 22 wherein said adhesive-free bonding material is substantially dry and comprises a mixture of said sugar or starch, aluminum chloride and ethylene glycol.
Claim 25
Dependent Claim 43 words
A method in accordance with claim 19 wherein said adhesive-free bonding material is dried after application and before pressing, and wherein said pressing operation is carried out in two stages, the first stage being cold pressing and the second stage being hot pressing.
Claim 26
Independent Claim 135 words
A method or providing a waterproof bond between solid lignocellulose materials, comprising: applying to said solid lignocellulose material an amount sufficient to effect bonding in the range of from 2-32 grams per 1000 cm 2 of area of said lignocellulosic material of an adhesive-free bonding composition having a pH after heating of 3.5 to 5.5 and comprising sugar, starch or mixtures thereof, an alkaline buffering agent, and catalyst capable of catalyzing transformation of the sugar and starch to the surface of the lignocellulose material, the amount of catalyst being from 1 to 100% by weight of the carbohydrate; and pressing said solid lignocellulose material together at about 140°-230° C. at a pressure in the range of about 5-50 kg/cm 2 for about 0.2 to 2 minutes per mm of thickness of said solid lignocellulosic material.
Claim 27
Independent Claim 135 words
A method or providing a waterproof bond between solid lignocellulose materials, comprising: applying to said solid lignocellulose material an amount sufficient to effect bonding in the range of from 2-32 grams per 1000 cm 2 of area of said lignocellulosic material of an adhesive-free bonding composition having a pH after heating of 3.5 to 5.5 and comprising sugar, starch or mixtures thereof, an alkaline buffering agent, and catalyst capable of catalyzing transformation of the sugar and starch to the surface of the lignocellulose material, the amount of catalyst being from 1 to 100% by weight of the carbohydrate; and pressing said solid lignocellulose material together at about 140°-230° C. at a pressure in the range of about 5-50 kg/cm 2 for about 0.2 to 2 minutes per mm of thickness of said solid lignocellulosic material.
Claim 28
Dependent Claim 37 words
A method in accordance with claim 1 wherein said layer of bonding material is applied as a composition of said sugar, starch or mixture thereof, and said catalyst and said alkaline material, and said composition is heated.
Claim 29
Dependent Claim 34 words
A method in accordance with claim 1 wherein said bonding material is applied as a layer containing up to 32 grams of added sugar, starch or mixture thereof per 1000 cm 2 of surface.
Claim 30
Dependent Claim 24 words
A method in accordance with claim 26 wherein said composition is applied in an amount sufficient to fill surface voids of said lignocellulosic material.
Claim 31
Independent Claim 146 words
A method of bonding solid lignocellulosic materials and thereby producing a waterproof bond, which comprises providing on a surface of said solid lignocellulosic material an adhesive-free bonding material consisting essentially of at least one sugar, starch or mixture thereof and an amount sufficient to catalyze transformation of the sugar or starch of a catalyst capable of transformation of the sugar or starch to cause waterproof bonding of adjacent lignocellulosic surfaces, said catalyst being selected from alkaline salts or a mixture of an alkaline material and an acidic salt so that said bonding material will not significantly lower the pH of the bonded lignocellulosic material and pressing surfaces of the lignocellulosic material together at en elevated temperature and for a time sufficient to effect said bonding by said transformation reactions of the carbohydrate, and wherein the time, temperature and pressure are sufficient to produce a waterproof bond.
Claim 32
Independent Claim 146 words
A method of bonding solid lignocellulosic materials and thereby producing a waterproof bond, which comprises providing on a surface of said solid lignocellulosic material an adhesive-free bonding material consisting essentially of at least one sugar, starch or mixture thereof and an amount sufficient to catalyze transformation of the sugar or starch of a catalyst capable of transformation of the sugar or starch to cause waterproof bonding of adjacent lignocellulosic surfaces, said catalyst being selected from alkaline salts or a mixture of an alkaline material and an acidic salt so that said bonding material will not significantly lower the pH of the bonded lignocellulosic material and pressing surfaces of the lignocellulosic material together at en elevated temperature and for a time sufficient to effect said bonding by said transformation reactions of the carbohydrate, and wherein the time, temperature and pressure are sufficient to produce a waterproof bond.
Claim 33
Dependent Claim 12 words
Waterproof, solid bonded lignocellulosic material, prepared by the process of claim 1.

References Cited (Backward Citations)

US2204384A Cited
US2495043A Cited
US2639994A Cited
US3565651A Cited
US4007312A Cited
US4107379A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-01-14 1983-07-16 1984-01-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-01-14 1987-07-16 1988-01-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-01-14 1991-07-16 1992-01-15 $7700.00 Window Closed / Lapsed

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