JPWO2020177111A5

JPWO2020177111A5 -

Info

Publication number: JPWO2020177111A5
Application number: JP2020542745A
Authority: JP
Publication date: 2023-05-23

Description

第２の態様では、本開示は、
（ａ）本開示によるホルムアルデヒド不含接着剤組成物を提供することと、
（ｂ）２以上の木材層を提供することと、
（ｃ）ホルムアルデヒド不含接着剤組成物を、該２以上の木材層のうちの１つまたは
２つの表面上に適用することと、
（ｄ）２以上の木材層を重ね、重ねた２以上の木材層を室温でプレスすることと、
（ｅ）重ねた２以上の木材層を５０～２００℃の高温でプレスすることと、を含む、
合板を生成するための方法を提供する。 In a second aspect, the disclosure provides:
(a) providing a formaldehyde-free adhesive composition according to the present disclosure;
(b) providing two or more wood layers ;
(c) applying a formaldehyde-free adhesive composition onto the surface of one or two of said two or more wood layers ;
(d) stacking two or more wood layers and pressing the stacked two or more wood layers at room temperature;
(e) pressing two or more superimposed wood layers at an elevated temperature of 50-200°C;
A method is provided for producing plywood.

この開示における水系ホルムアルデヒド不含木材バインダーは、水分散性イソシアネート架橋剤、アクリレート系ポリマーエマルジョン、および充填剤などの他の成分を用いて開発された。既存のホルムアルデヒド系バインダー（ＰＦまたはＵＦ）と比較して、本開示の接着剤組成物は、ホルムアルデヒド成分なし、ホルムアルデヒド放出なし、低い硬化温度（１００～１２０℃）、短い硬化時間（１ｍｍの木材ボードに対して１分）、長いポットライフ（＞４時間、バインダーの調製から木材への適用までの期間を指す）、および接着性能試験での同等の性能の利点を有する。
本願は以下の態様にも関する。
(１) ホルムアルデヒド不含接着剤組成物であって、
（ａ）アクリルポリマーの水性エマルジョンと、
（ｂ）脂肪族イソシアネート架橋剤（複数可）と、を含み、
前記アクリルポリマーが、少なくとも１つのヘテロ官能基を担持する１つ以上のエチレン性不飽和モノマーの少なくとも１つの構造単位を有し、前記アクリルポリマーが、－４５℃～０℃のガラス転移温度を有する、ホルムアルデヒド不含接着剤組成物。
(２) 前記ヘテロ官能基が、ウレイド、ニトリル、アルコキシシラン、およびリン基からなる群から選択される、上記(１)に記載の接着剤組成物。
(３) 前記アクリルポリマーが、－４５℃～０℃のガラス転移温度を有する、上記(１)に記載の接着剤組成物。
(４) 前記アクリルポリマーが、ヒドロキシ含有モノマーの構造単位を含まない、上記(１)に記載の接着剤組成物。
(５) 前記アクリルポリマーの水性エマルジョンが、９以下のｐＨを有する、上記(１)に記載の接着剤組成物。
(６) 充填剤、レオロジー調整剤、および消泡剤の群から選択される１つ以上の添加剤をさらに含む、上記(１)に記載の接着剤組成物。
(７) シランをさらに含む、上記(１)に記載の接着剤組成物。
(８) 前記脂肪族イソシアネート架橋剤が、親水性修飾ＨＤＩプレポリマーである、上記(１)に記載の接着剤組成物。
(９) 合板を生成するための方法であって、
（ａ）上記(１)～(８)のいずれか一項に記載のホルムアルデヒド不含接着剤組成物を提供することと、
（ｂ）２以上の木材層を提供することと、
（ｃ）前記ホルムアルデヒド不含接着剤組成物を、前記２以上の木材層のうちの１つまたは２つの表面上に適用することと、
（ｄ）２以上の木材層を重ね、前記重ねた２以上の木材を室温でプレスすることと、
（ｅ）前記重ねた２以上の木材層を５０～２００℃の高温でプレスすることと、を含む、合板を生成するための方法。
(１０) 上記の方法によって得られた前記合板が、３～１１層の木材を含む、上記(９)に記載の方法。
(１１) 上記(１)～(８)のいずれか一項に記載のホルムアルデヒド不含接着剤組成物によって得られる、合板。 The water-based formaldehyde-free wood binders in this disclosure were developed using water-dispersible isocyanate crosslinkers, acrylate-based polymer emulsions, and other ingredients such as fillers. Compared to existing formaldehyde-based binders (PF or UF), the adhesive composition of the present disclosure has no formaldehyde component, no formaldehyde emission, low curing temperature (100-120°C), short curing time (1mm wood board 1 minute for the adhesive), long pot life (>4 hours, which refers to the period from preparation of the binder to its application to the wood), and comparable performance in the adhesion performance test.
The present application also relates to the following aspects.
(1) A formaldehyde-free adhesive composition comprising:
(a) an aqueous emulsion of an acrylic polymer;
(b) an aliphatic isocyanate crosslinker(s);
The acrylic polymer has at least one structural unit of one or more ethylenically unsaturated monomers carrying at least one heterofunctional group, and the acrylic polymer has a glass transition temperature of -45°C to 0°C. , formaldehyde-free adhesive compositions.
(2) The adhesive composition according to (1) above, wherein the heterofunctional group is selected from the group consisting of ureido, nitrile, alkoxysilane, and phosphorus groups.
(3) The adhesive composition as described in (1) above, wherein the acrylic polymer has a glass transition temperature of -45°C to 0°C.
(4) The adhesive composition according to (1) above, wherein the acrylic polymer does not contain a structural unit of a hydroxy-containing monomer.
(5) The adhesive composition according to (1) above, wherein the aqueous emulsion of the acrylic polymer has a pH of 9 or less.
(6) The adhesive composition according to (1) above, further comprising one or more additives selected from the group of fillers, rheology modifiers, and defoamers.
(7) The adhesive composition according to (1) above, further comprising a silane.
(8) The adhesive composition according to (1) above, wherein the aliphatic isocyanate cross-linking agent is a hydrophilic modified HDI prepolymer.
(9) A method for producing plywood comprising:
(a) providing the formaldehyde-free adhesive composition according to any one of (1) to (8) above;
(b) providing two or more wood layers;
(c) applying the formaldehyde-free adhesive composition onto the surface of one or two of the two or more wood layers;
(d) stacking two or more layers of wood and pressing the stacked two or more layers of wood at room temperature;
(e) pressing the superimposed two or more wood layers at a high temperature of 50-200°C.
(10) The method according to (9) above, wherein the plywood obtained by the above method comprises 3 to 11 layers of wood.
(11) Plywood obtained by the formaldehyde-free adhesive composition according to any one of (1) to (8) above.

Claims

A formaldehyde-free adhesive composition comprising:
(a) an aqueous emulsion of an acrylic polymer;
(b) an aliphatic isocyanate crosslinker(s);
The acrylic polymer has at least one structural unit of one or more ethylenically unsaturated monomers carrying at least one heterofunctional group, and the acrylic polymer has a glass transition temperature of -45°C to 0°C. death,
the aqueous emulsion of the acrylic polymer has a pH of 9 or less;
The adhesive composition has a pot life of greater than 4 hours,
Formaldehyde-free adhesive composition.

2. The adhesive composition of claim 1, wherein said heterofunctional group is selected from the group consisting of ureido, nitrile, alkoxysilane, and phosphorous groups.

The adhesive composition of claim 1, wherein said acrylic polymer has a glass transition temperature of -45°C to 0°C.

2. The adhesive composition of claim 1, wherein the acrylic polymer does not contain structural units of hydroxy-containing monomers.

2. The adhesive composition of claim 1, further comprising one or more additives selected from the group of fillers, rheology modifiers, and defoamers.

The adhesive composition of Claim 1, further comprising a silane.

The adhesive composition of Claim 1, wherein said aliphatic isocyanate crosslinker is a hydrophilically modified HDI prepolymer.

A method for producing plywood comprising:
(a) providing a formaldehyde-free adhesive composition according to any one of claims 1-7 ;
(b) providing two or more wood layers ;
(c) applying the formaldehyde-free adhesive composition onto the surface of one or two of the two or more wood layers ;
(d) stacking two or more layers of wood and pressing the stacked two or more layers of wood at room temperature;
(e) pressing the superimposed two or more wood layers at a high temperature of 50-200°C.

A method according to claim 8 , wherein the plywood obtained by the above method comprises 3 to 11 wood layers .

Plywood obtained with a formaldehyde-free adhesive composition according to any one of claims 1-7 .