Commonwealth Scientific and Industrial Research Organisation

Wood One Co., Ltd.

Beijing University of Technology

Kabushiki Kaisha Wood One

Huntsman Chemical Company Australia Limited

Chemplex Australia Limited

Yoshikazu Yazaki

Peter J Collins

Yusho Nakamoto

Masayoshi Horito

Naoko Kurushima

Tomoyuki Matsumae

Hiroyuki Yano

Keiko Ono

Frank Lawson

Toshihiko Tsunoda

Huijian Jiang

Peter Heinz Theodore Uhlherr

Michael J Delaney

Provided is an adhesive that effectively utilizes bark and demonstrates superior adhesion performance. The adhesive of the present invention comprises at least one adhesive resin (A) selected from the group consisting of phenolic resin, urea resin, and melamine resin, and finely pulverized bark (B) comprising cellulose nanofibers.

Adhesive

Provided is an adhesive using bark, which is advantageous not only in that the proportion of the bark is increased so as to effectively utilize the bark, and the proportion of the phenolic resin is reduced to lower the adhesive solids content, but also in that the composition of the adhesive is simple. An adhesive using bark, which comprises a resol type phenolic resin and a radiata pine bark powder, wherein the adhesive contains 30 to 40 parts by mass of the radiata pine bark powder, relative to 100 parts by mass of the total of the resol type phenolic resin solids and the radiata pine bark powder. Alternatively, an adhesive using bark, which comprises a resol type phenolic resin and a radiata pine bark powder, wherein the adhesive contains 20 to 50 parts by mass of the radiata pine bark powder and wheat flour, relative to 100 parts by mass of the total of the resol type phenolic resin solids, the radiata pine bark powder, and the wheat flour, and wherein the mass ratio of the radiata pine bark powder and the wheat flour is 9:1 to 5:5.

Adhesive using bark

A method of producing powder with a high tannin content includes pulverizing a tannin-containing plant such as bark of radiata pine () and classifying the pulverized material into fine particles having a desired particle size, for example, fine particles having a particle diameter of 100 to 1,000 &#x3bc;m or less. A powder with a high tannin content is produced by such a method. The thus obtained powder with a high tannin content exhibits excellent characteristics when used as an adhesive, a binder, etc. for wood materials.

Method for the production of powder with high tannin content and its use

Adhesive composition

A method for producing a relatively low viscosity tannin extract from bark and/or wood and suitable for use in formaldehyde-condensation adhesives comprises providing tannin extract obtained from bark and/or wood, separating from the tannin extract the high molecular weight material, subjecting the high molecular weight material to treatment with one or more sulphite compounds to reduce the molecular weight and recombining the sulphited material with the tannin extract. The tannin extract may be recovered by subjecting bark and/or wood to a first stage hot aqueous tannin extraction process, thereby obtaining a first stage tannin extract, subjecting the extracted bark and/or wood to a second stage hot aqueous extraction process at a higher pH than the first stage, thereby obtaining a second stage tannin extract, and optionally recombining the first and second stage tannin extracts.

Tannin extraction and processing

A wood adhesive composition including an effective amount of a phenol-formaldehyde resin; and a modifying agent which agent renders the composition capable of bonding to a hard wood.

Growing community of inventors

Moorabbin, Australia

Yoshikazu Yazaki