JP4871790B2

JP4871790B2 - Laminate production method

Info

Publication number: JP4871790B2
Application number: JP2007144344A
Authority: JP
Inventors: 束田中; 崇杉山; 薫中鉢
Original assignee: Koyo Sangyo Co Ltd
Current assignee: Koyo Sangyo Co Ltd
Priority date: 2007-05-31
Filing date: 2007-05-31
Publication date: 2012-02-08
Anticipated expiration: 2027-05-31
Also published as: JP2008296437A

Description

本発明は、植物茎を主原料とする積層材の製造方法に関する。更に詳しくは襖や間仕切り又はこれらの芯材に適する積層材の製造方法に関するものである。 The present invention relates to a method for producing a laminated material using a plant stem as a main raw material. More specifically, the present invention relates to a method for manufacturing a laminated material suitable for a bag, a partition, or a core material thereof.

本出願人は、この種の積層材の製造方法として、コウリャン茎に代表されるリグノセルロース茎を繊維方向に切開き、このリグノセルロース茎を圧延して片面が茎の表皮からなる圧延茎を形成し、複数の圧延茎を互いに平行に配列してシート状物を形成し、このシート状物に高分子樹脂接着剤を塗工し、この接着剤を塗工した複数のシート状物を重ね合せて熱圧成形する積層材の製造方法を特許出願した（例えば、特許文献１参照。）。この方法によれば、市販合板及び従来の加工木材に比較して同等もしくはそれ以上の強度を有し、高い吸音性及び断熱性があって、低密度から高密度の積層材が得られる。 As a method of manufacturing this type of laminated material, the present applicant cuts lignocellulose stalks represented by sorghum stalks in the fiber direction, and rolls the lignocellulose stalks to form a rolled stalk having one side of the stem skin. Then, a plurality of rolled stems are arranged in parallel to each other to form a sheet-like material, a polymer resin adhesive is applied to the sheet-like material, and the plurality of sheet-like materials coated with the adhesive are overlapped. Have filed a patent application for a method for producing a laminated material to be hot-pressed (see, for example, Patent Document 1). According to this method, a laminate material having a strength equal to or higher than that of commercially available plywood and conventional processed wood, high sound absorption and heat insulation, and low to high density can be obtained.

しかし、上記積層材はコウリャン茎を繊維方向に切開いた後、圧延して製造されるものであるため、より低い密度でより高い吸音性及び断熱性を具備させることが困難で、製造工数を比較的多く費やす。このため、本出願人は、コウリャン茎を繊維方向に切開かずに表皮、芯及び節を有したまま圧延し、圧延面が層表面及び層裏面となるように複数のコウリャン茎を互いに平行にかつ密接に配列してコウリャン茎層を形成し、このコウリャン茎層に接着剤を塗布し、接着剤を塗布した複数のコウリャン茎層を積層して加圧成形する積層材の製造方法を特許出願した（例えば、特許文献２参照。）。この方法によれば、軽量で強度が高く簡単な工程で効率よく積層材を製造でき、また少量の原料で厚板を構成でき、更に圧延度が大きい場合には高密度化も可能となる。
特開昭６３−１０７５０５（特許請求の範囲第４項）特開平１−２８０５３８（請求項５） However, since the above laminated material is manufactured by rolling after cutting the sorghum stalk in the fiber direction, it is difficult to provide higher sound absorption and heat insulation at a lower density, and the manufacturing man-hours are compared. Spend a lot of money. For this reason, the present applicant rolled the sorghum stalks without cutting them in the fiber direction while having the skin, core and nodes, and the plurality of sorghum stalks in parallel with each other so that the rolled surface becomes the layer surface and the layer back surface. A patent application was filed for a method of manufacturing a laminated material in which a colander stalk layer was formed by closely arranging, an adhesive was applied to the cucurian stalk layer, and a plurality of colander stalk layers coated with the adhesive were laminated and pressed. (For example, refer to Patent Document 2). According to this method, a laminated material can be efficiently produced by a simple process with a light weight and high strength, a thick plate can be formed with a small amount of raw material, and a higher density can be achieved when the rolling degree is large.
JP 63-107505 (Claim 4) JP-A-1-280538 (Claim 5)

一般的に、襖や間仕切り又はその芯材などは、低密度かつ高強度であって、表面平滑性が良好で、反りなどの変形が少なく変色が無いことが要求される。コウリャン茎に代表されるリグノセルロース茎を表面材のない芯材又は薄い表面材を有する芯材として使用する場合、コウリャン茎には節が膨出しているため、切開いた茎も切開かない茎もシート状物にしたときに、シート状物表面の凹凸度が大きい。そのため、複数のシート状物を重ね合わせて積層体にしたときに、シート状物同士の間に比較的大きな空隙を生じる。この積層体に接着剤を塗布し表面材なしで、或いは薄い表面材を積層して、低密度の積層材を得るために圧締度を低くして成形した場合には、茎の節付近に茎間の隙間が生じて積層材の表面平滑性が劣る不具合があった。 In general, ridges, partitions or their core materials are required to have low density and high strength, good surface smoothness, little deformation such as warpage, and no discoloration. When lignocellulosic stems typified by sorghum stalks are used as a core material without a surface material or as a core material having a thin surface material, because swells on the sorghum stalks, both incised stalks and non-incised stalks are sheets. When a sheet is formed, the degree of unevenness on the surface of the sheet is large. Therefore, when a plurality of sheet-like objects are overlapped to form a laminated body, a relatively large gap is generated between the sheet-like objects. When this laminate is coated with an adhesive and without a surface material, or by laminating a thin surface material to form a low-density laminated material with a low degree of clamping, There was a problem that the surface smoothness of the laminated material was inferior due to a gap between the stems.

一方、リグノセルロース茎は表皮にワックスが存在するため、接着剤として表皮にワックスが存在しても高温で接着力を発現する自己乳化型ポリイソシアネート樹脂接着剤を用いることが考えられる。しかし、表面材として薄い熱硬化性樹脂シート、熱可塑性樹脂シート、単板、合板、布帛、紙、板紙、段ボール紙又は表面コート紙を用いて、１５０℃程度の高温で圧締成形した場合には、低密度で高い強度の積層材が得られる反面、この表面材は熱により変色したり、積層材に反りが発生する不具合があった。他方、接着剤として低温で接着力を発現する水性高分子−イソシアネート系接着剤を用いて積層体に接着剤を塗布し、表面材を積層して４０℃程度の低温で圧締成形した場合には、表面材の熱変色や積層材の反りが発生しない反面、この接着剤は茎表皮のワックスとの相溶性が悪いために積層体に対する接着性に劣り、低密度の積層材は得られるものの強度が低かった。 On the other hand, since lignocellulose stems have wax in the skin, it is conceivable to use a self-emulsifying polyisocyanate resin adhesive that exhibits adhesive strength at high temperatures even when wax is present in the skin. However, when a thin thermosetting resin sheet, thermoplastic resin sheet, veneer, plywood, fabric, paper, paperboard, corrugated paper or surface-coated paper is used as the surface material and pressed at a high temperature of about 150 ° C. Although a low-density and high-strength laminated material can be obtained, this surface material has a problem that it is discolored by heat or the laminated material is warped. On the other hand, when an adhesive is applied to a laminate using an aqueous polymer-isocyanate adhesive that exhibits adhesive strength at low temperatures as an adhesive, and a surface material is laminated and pressed at a low temperature of about 40 ° C. Although the surface material does not undergo thermal discoloration or warping of the laminated material, this adhesive has poor compatibility with the wax of the stem skin, so it is inferior in adhesion to the laminated body, but a low-density laminated material can be obtained. The strength was low.

このため、自己乳化型ポリイソシアネート樹脂接着剤を用いる場合には、熱硬化性樹脂シートや熱可塑性樹脂シートの表面材を設けずに高温で積層体を圧締成形してから、その後表面材を冷圧で貼り合わせる必要がある。また水性高分子−イソシアネート系接着剤を用いる場合には、リグノセルロース茎の表皮からワックスを除去する前処理を行う必要があった。 For this reason, when using a self-emulsifying type polyisocyanate resin adhesive, after pressing the laminate at a high temperature without providing a surface material of a thermosetting resin sheet or a thermoplastic resin sheet, the surface material is then used. It is necessary to stick together with cold pressure. In the case of using an aqueous polymer-isocyanate adhesive, it is necessary to perform a pretreatment for removing the wax from the skin of the lignocellulose stem.

本発明の目的は、複数本のキク科植物茎を用いて、茎の脱脂処理を要することなく、低密度で高い強度を有し、変色や反りやねじれのない、表面平滑性の良好な積層材を製造する方法を提供することにある。 The object of the present invention is to use a plurality of Asteraceae plant stems, and without requiring a degreasing treatment of the stems, has a low density and high strength, and has good surface smoothness without discoloration, warping or twisting. It is to provide a method of manufacturing a material.

本願請求項１に係る発明は、図１〜図３に示すように、複数本の乾燥したキク科植物茎１１の含水率を１０〜５０％に調整する工程と、この含水率を調整した複数本の植物茎１１をそれぞれ繊維方向に切開して２つに分割することにより複数本の半割茎１２，１２を得る工程と、これらの半割茎１２を各髄部１２ａが同一面になるようにかつそれぞれ繊維方向に配列し半割茎１２を糸１３又はテープで結合して第１及び第２シート状物１４，１５を形成する工程と、これらのシート状物１４，１５に接着剤をそれぞれ付着させる工程と、それぞれ接着剤が付着した第１シート状物１４と第２シート状物１５とを各髄部１２ａが外側になるように重ね合わせて接着剤付き積層体１６を得る工程と、この接着剤付き積層体１６を厚さが５〜２０％減少するように圧締成形して積層材２０を得る工程とを含む積層材の製造方法である。 As shown in FIGS. 1 to 3, the invention according to claim 1 of the present application includes a step of adjusting the moisture content of a plurality of dried asteraceae plant stems 11 to 10 to 50%, and a plurality of adjusted moisture content. Each of the plant stems 11 is cut in the fiber direction and divided into two parts to obtain a plurality of half split stems 12 and 12, and each of the half split stems 12 has the same medulla portion 12a. And forming the first and second sheet-like materials 14 and 15 by arranging the half split stems 12 with the yarn 13 or the tape and arranging them in the fiber direction, respectively, and an adhesive agent on these sheet-like materials 14 and 15 And a step of obtaining a laminated body 16 with an adhesive by superimposing the first sheet-like material 14 and the second sheet-like material 15 to which the adhesive is respectively attached so that the medulla portions 12a are on the outside. And this laminated body 16 with adhesive has a thickness of 5 to 20%. A method for producing a laminated material comprising the steps of obtaining a clamping molding to laminate 20 to low.

本願請求項２に係る発明は、請求項１に係る発明であって、第１シート状物１４を構成する半割茎１２の各表皮１２ｂ頂部を第２シート状物１５を構成する半割茎１２の各表皮１２ｂ頂部とずらして重ね合わせる積層材の製造方法である。 The invention according to claim 2 of the present application is the invention according to claim 1, in which the top part of each epidermis 12b of the half split stem 12 constituting the first sheet-like material 14 is the half split stem constituting the second sheet-like matter 15. 12 is a method of manufacturing a laminated material that is shifted and superposed on the top of each of the 12 skins 12b.

本願請求項３に係る発明は、請求項１又は２に係る発明であって、接着剤付き積層体１６の片面又は両面に更に表面材１８を重ね合わせた後、圧締成形する積層材の製造方法である。 The invention according to claim 3 of the present application is the invention according to claim 1 or 2, in which the surface material 18 is further overlapped on one or both sides of the laminate 16 with adhesive, and then the laminate is pressed. Is the method.

本願請求項４に係る発明は、請求項３に係る発明であって、表面材が熱硬化性樹脂シート、熱可塑性樹脂シート、単板、合板、布帛、紙、板紙、段ボール紙又は表面コート紙である積層材の製造方法である。 The invention according to claim 4 is the invention according to claim 3, wherein the surface material is a thermosetting resin sheet, a thermoplastic resin sheet, a veneer, a plywood, a fabric, a paper, a paperboard, a corrugated paper, or a surface-coated paper. It is a manufacturing method of the laminated material which is.

本願請求項５に係る発明は、請求項１ないし３いずれか１項に係る発明であって、接着剤が水性高分子−イソシアネート系接着剤であって、接着剤付き積層体を５〜８０℃の温度で圧締成形する積層材の製造方法である。 The invention according to claim 5 of the present application is the invention according to any one of claims 1 to 3, wherein the adhesive is an aqueous polymer-isocyanate adhesive, and the laminate with the adhesive is 5 to 80 ° C. It is a manufacturing method of the laminated material which press-molds at the temperature of.

本願請求項６に係る発明は、請求項１ないし５いずれか１項に係る発明であって、キク科植物茎がヒマワリ、ヒメヒマワリ、ノコギリソウ、ヨモギ、ヒナギク、エゾギク、ベニバナ、キク、コスモス、ダリア、タンポポ又はフキである積層材の製造方法である。 The invention according to claim 6 of the present application is the invention according to any one of claims 1 to 5, wherein the stems of the Asteraceae plant are sunflower, sunflower, yarrow, mugwort, daisies, ezogiku, safflower, chrysanthemum, cosmos, dahlia. A method for producing a laminated material which is a dandelion or a balloon.

本願請求項７に係る発明は、請求項１ないし６いずれか１項の方法により製造された積層材である。 The invention according to claim 7 of the present application is a laminated material manufactured by the method according to any one of claims 1 to 6.

本願請求項１に係る製造方法では、半割茎にする前にキク科植物茎の含水率を調整することにより、茎の分割切断が容易にかつ正確になり切断面が平滑になる。またその半割茎を繊維方向に配列してなる２つのシート状物を半割茎の各髄部が外側になるように重ね合わせて接着することにより積層体を作り、これを積層体厚さの５〜２０％になるように圧締成形するため、低密度で強度が高くかつ表面が平滑で反りやねじれのない積層材が得られる。 In the manufacturing method according to claim 1 of the present application, by adjusting the moisture content of the asteraceae plant stem before making the half-cut stem, the divided cut of the stem becomes easy and accurate, and the cut surface becomes smooth. In addition, a laminate is made by stacking and adhering two sheet-like materials in which the half split stems are arranged in the fiber direction so that each medullary portion of the half split stem is on the outside. Therefore, a laminated material having a low density, a high strength, a smooth surface, and no warping or twisting can be obtained.

本願請求項２に係る製造方法では、２つのシート状物を重ね合わせるときに半割茎の各表皮頂部をずらすため、茎間の空隙の少ない積層体となり、より強度の高い積層材が得られる。 In the manufacturing method according to claim 2 of the present application, the tops of the half split stems are shifted when two sheet-like materials are overlapped, so that a laminate with less space between the stems is obtained, and a laminate with higher strength is obtained. .

本願請求項３及び４に係る製造方法では、接着剤付き積層体の片面又は両面に表面材を設けることにより、例えば表面材に厚さ０．０１〜１ｍｍの樹脂シート、板、布、紙を用いることにより、表面がより平滑になって強度がより向上するとともに表面材によって積層材の装飾性が高まりかつその用途が拡大する。 In the manufacturing method according to claims 3 and 4 of the present application, by providing a surface material on one side or both sides of the laminate with adhesive, for example, a resin sheet, plate, cloth, paper having a thickness of 0.01 to 1 mm is applied to the surface material. By using it, the surface becomes smoother and the strength is further improved, and the decorativeness of the laminated material is enhanced by the surface material and its use is expanded.

本願請求項５に係る製造方法では、イソシアネート系化合物を架橋剤として含む水溶性高分子又は高分子水性分散体からなる水性高分子−イソシアネート系接着剤を用いることにより、キク科植物茎を脱脂しなくても、５〜８０℃の低温で積層体を接着することができる。 In the manufacturing method according to claim 5 of the present application, a sterilized plant stem is degreased by using an aqueous polymer-isocyanate adhesive comprising a water-soluble polymer or polymer aqueous dispersion containing an isocyanate compound as a crosslinking agent. Even if it does not exist, a laminated body can be adhere | attached at the low temperature of 5-80 degreeC.

以下、本発明の最良の実施の形態について説明する。本発明のキク科植物茎としては、ヒマワリ、ヒメヒマワリ、ノコギリソウ、ヨモギ、ヒナギク、エゾギク、ベニバナ、キク、コスモス、ダリア、タンポポ又はフキが例示される。この植物茎は植生地から刈り取られた後、積層材の原料として保管する間、含有する水分により腐食するのを防止するために、天日などで含水率４〜８％の範囲に乾燥される。次いで、乾燥した植物茎は所望の積層材の長さに合わせて一定の長さに切断された後、或いは切断される前に、茎の含水率が１０〜５０％、好ましくは２０〜４０％に調整される。これは次の茎を２つに分割するときに、分割が容易になるとともに切断面を平滑かつきれいにするためである。含水率が１０％未満の乾燥したままであると、茎が硬くて分割しにくく分割茎のサイズが不揃いになるうえ、切断面がささくれ立ってきれいになりにくい。また含水率が５０％を超えると水分過多となり、最終製品である積層材が低密度にならない。含水率を調整する方法としては、乾燥した植物茎を温度５〜１００℃、相対湿度８０〜１００％の雰囲気に所定時間維持する方法や乾燥した植物茎を水に所定時間浸漬する方法が挙げられる。熱した蒸気中に植物茎を暴露する方法が短時間に茎の含水率を調整でき好ましい。 The best mode of the present invention will be described below. Examples of the Asteraceae plant stem of the present invention include sunflower, sunflower, yarrow, mugwort, daisies, ezogiku, safflower, chrysanthemum, cosmos, dahlia, dandelion, or dandruff. This plant stem is cut from the vegetation and then dried to a moisture content in the range of 4 to 8% in the sun to prevent it from being corroded by moisture contained during storage as a raw material for the laminated material. . Then, after the dried plant stem is cut to a certain length according to the desired length of the laminated material, or before being cut, the moisture content of the stem is 10 to 50%, preferably 20 to 40%. Adjusted to This is because when the next stem is divided into two, the division becomes easy and the cut surface becomes smooth and clean. If the moisture content is less than 10%, the stems are hard and difficult to divide, and the sizes of the divided stalks are not uniform, and the cut surfaces do not stand up and become difficult to clean. On the other hand, if the water content exceeds 50%, the water content becomes excessive, and the laminated material as the final product does not become low density. Examples of the method for adjusting the moisture content include a method of maintaining a dried plant stem in an atmosphere having a temperature of 5 to 100 ° C. and a relative humidity of 80 to 100% for a predetermined time, and a method of immersing the dried plant stem in water for a predetermined time. . A method in which the plant stem is exposed to heated steam is preferable because the moisture content of the stem can be adjusted in a short time.

次に、図１（ａ）及び（ｂ）に示すように、一定の長さに切断され含水率が調整された植物茎１１は繊維方向に切開して２つに分割され半割茎１２，１２にする。１２ａは髄部であり、１２ｂは表皮である。所望の積層材の幅に合わせて複数本の半割茎１２が集められる。図２に示すように複数本の半割茎１２は各髄部１２ａが同一面になるようにかつそれぞれ繊維方向に配列された後、半割茎同士が結合される。結合方法としては、図示するように糸１３で縫合するか、又は図示しないが、粘着テープを貼着することにより複数本の半割茎が仮止めされる。これによりシート状物１４又は１５が形成される。 Next, as shown in FIGS. 1 (a) and 1 (b), the plant stem 11 which has been cut to a certain length and the moisture content has been adjusted is cut in the fiber direction and divided into two half stalks 12, Set to 12. 12a is the medulla and 12b is the epidermis. A plurality of half split stems 12 are collected according to the desired width of the laminated material. As shown in FIG. 2, the plurality of half split stems 12 are arranged in the fiber direction so that the medulla portions 12 a are on the same plane, and then the half split stems are joined together. As a coupling method, a plurality of half split stems are temporarily fixed by sewing with a thread 13 as shown, or by sticking an adhesive tape, although not shown. Thereby, the sheet-like object 14 or 15 is formed.

次に、２つのシート状物１４，１５に接着剤をそれぞれ付着させる。付着方法としては、接着剤をシート状物にスプレーコーティング、カーテンフローコーティング、ローラコーティングするか、刷毛塗りするか、又は接着剤にディッピングする。後述する表面材を設けないときには、接着剤はシート状物を構成する各表皮部分にのみ付着される。接着剤としては、水溶性高分子又は高分子水性分散体のいずれか一方又は双方を主成分とする主剤８０〜９５質量％と、イソシアネート系化合物を主成分とする架橋剤２０〜５質量％とからなる水性高分子−イソシアネート系接着剤が好ましい。 Next, an adhesive is attached to each of the two sheet-like materials 14 and 15. As an adhesion method, the adhesive is spray coated, curtain flow coated, roller coated, brushed, or dipped on the adhesive. When a surface material to be described later is not provided, the adhesive is attached only to the respective skin portions constituting the sheet-like material. As the adhesive, 80 to 95% by mass of a main component mainly composed of one or both of a water-soluble polymer and an aqueous polymer dispersion, and 20 to 5% by mass of a crosslinking agent mainly composed of an isocyanate compound, An aqueous polymer-isocyanate adhesive comprising

水性高分子―イソシアネート系接着剤と自己乳化型ポリイソシアネート樹脂接着剤は、異なる接着剤である。水性高分子-イソシアネート系接着剤は主剤に高分子成分を含み、それが架橋剤であるイソシアネート化合物と反応することによって、更に高分子化するため、接着力が発現しやすい。従って室温でも容易に硬化する。自己乳化型ポリイソシアネート樹脂接着剤はモノマーやオリゴマーの反応により主として反応が進むため、熱圧で反応を促進しないと高分子化しにくく接着力が出にくい。また室温では硬化に時間がかかる。 The aqueous polymer-isocyanate adhesive and the self-emulsifying polyisocyanate resin adhesive are different adhesives. The aqueous polymer-isocyanate-based adhesive contains a polymer component as a main component, and further reacts with an isocyanate compound as a cross-linking agent to further polymerize, so that an adhesive force is easily developed. Therefore, it hardens easily even at room temperature. The self-emulsifying type polyisocyanate resin adhesive is mainly reacted by the reaction of monomers and oligomers. Therefore, unless the reaction is accelerated by hot pressure, it is difficult to polymerize and to exert an adhesive force. Also, it takes time to cure at room temperature.

ここで水溶性高分子としては、ポリビニルアルコール、カルボキシメチルセルロース及びポリアクリル酸からなる群より選ばれた少なくとも１種の化合物が好ましい。また高分子水性分散体としては、酢酸ビニル、スチレン−アクリル共重合体、酢酸ビニル−アクリル酸エステル共重合体、エチレン−酢酸ビニル共重合体、スチレン−ブタジエン共重合体及びアクリロニトリル−ブタジエン共重合体からなる群より選ばれた少なくとも１種の化合物が好ましい。 Here, the water-soluble polymer is preferably at least one compound selected from the group consisting of polyvinyl alcohol, carboxymethyl cellulose and polyacrylic acid. Polymeric aqueous dispersions include vinyl acetate, styrene-acrylic copolymer, vinyl acetate-acrylic acid ester copolymer, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, and acrylonitrile-butadiene copolymer. At least one compound selected from the group consisting of

イソシアネート化合物としては、脂肪族ポリイソシアネート、脂環式ポリイソシアネート、芳香族ポリイソシアネート、芳香脂肪族ポリイソシアネートなどのポリイソシアネート系化合物が挙げられる。脂肪族ポリイソシアネートとしては、例えば、１，３−トリメチレンジイソシアネート、１，４−テトラメチレンジイソシアネ−ト、１，３−ペンタメチレンジイソシアネート、１，５−ペンタメチレンジイソシアネート、１，６−ヘキサメチレンジイソシアネ−ト、１，２−プロピレンジイソシアネート、１，２−ブチレンジイソシアネート、２，３−ブチレンジイソシアネート、１，３−ブチレンジイソシアネート、２−メチル−１，５−ペンタメチレンジイソシアネート、３−メチル−１，５−ペンタメチレンジイソシアネート、２，４，４−トリメチル−１，６−ヘキサメチレンジイソシアネート、２，２，４−トリメチル−１，６−ヘキサメチレンジイソシアネート、２，６−ジイソシアネートメチルカプロエート、リジンジイソシアネ−ト等が挙げられる。 Examples of the isocyanate compound include polyisocyanate compounds such as aliphatic polyisocyanate, alicyclic polyisocyanate, aromatic polyisocyanate, and araliphatic polyisocyanate. Examples of the aliphatic polyisocyanate include 1,3-trimethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,3-pentamethylene diisocyanate, 1,5-pentamethylene diisocyanate, 1,6-hexa Methylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, 2-methyl-1,5-pentamethylene diisocyanate, 3-methyl -1,5-pentamethylene diisocyanate, 2,4,4-trimethyl-1,6-hexamethylene diisocyanate, 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, 2,6-diisocyanate methyl caproate Lysine diiso Ane - door, and the like.

また脂環式ポリイソシアネートとしては、例えば、１，３−シクロペンタンジイソシアネート、１，４−シクロヘキサンジイソシアネート、１，３−シクロヘキサンジイソシアネート、３−イソシアネートメチル−３，５，５−トリメチルシクロヘキシルイソシアネート、４，４’−メチレンビス（シクロヘキシルイソシアネート）、メチル−２，４−シクロヘキサンジイソシアネート、メチル−２，６−シクロヘキサンジイソシアネート等が挙げられる。また芳香族ポリイソシアネートとしては、例えば、ｍ−フェニレンジイソシアネ−ト、ｐ−フェニレンジイソシアネ−ト、２，４−トリレンジイソシアネ−ト、２，６−トリレンジイソシアネ−ト、ナフチレン−１，４−ジイソシアネ−ト、ナフチレン−１，５−ジイソシアネ−ト、４，４’−ジフェニルジイソシアネ−ト、４，４’−ジフェニルメタンジイソシアネ−ト、２，４’−ジフェニルメタンジイソシアネ−ト、４，４’−ジフェニルエ−テルジイソシアネ−ト、２−ニトロジフェニル−４，４’−ジイソシアネ−ト、２，２’−ジフェニルプロパン−４，４’−ジイソシアネ−ト、３，３’−ジメチルジフェニルメタン−４，４’−ジイソシアネート、４，４’−ジフェニルプロパンジイソシアネ−ト、３，３’−ジメトキシジフェニル−４，４’−ジイソシアネ−ト等が挙げられる。 Examples of the alicyclic polyisocyanate include 1,3-cyclopentane diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate, 4, Examples include 4'-methylenebis (cyclohexyl isocyanate), methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, and the like. Examples of the aromatic polyisocyanate include m-phenylene diisocyanate, p-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, Naphthylene-1,4-diisocyanate, naphthylene-1,5-diisocyanate, 4,4'-diphenyldiisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane Diisocyanate, 4,4'-diphenyl ether diisocyanate, 2-nitrodiphenyl-4,4'-diisocyanate, 2,2'-diphenylpropane-4,4'-diisocyanate, 3 , 3′-dimethyldiphenylmethane-4,4′-diisocyanate, 4,4′-diphenylpropane diisocyanate, 3,3′-dimethoxydi Eniru-4,4'-diisocyanate - door, and the like.

更に芳香脂肪族ポリイソシアネートとしては、例えば、１，３−キシリレンジイソシアネ−ト、１，４−キシリレンジイソシアネ−ト、ω，ω’−ジイソシアネート−１，４−ジエチルベンゼン、１，３−ビス（１−イソシアネート−１−メチルエチル）ベンゼン、１，４−ビス（１−イソシアネート−１−メチルエチル）ベンゼン、１，３−ビス（α，α−ジメチルイソシアネートメチル）ベンゼン等が挙げられる。なお、この実施の形態では、イソシアネート系化合物としては、上記例示の脂肪族ポリイソシアネ−ト、脂環式ポリイソシアネ−ト、芳香族ポリイソシアネ−ト、芳香脂肪族ポリイソシアネ−トによる二量体や三量体、反応生成物又は重合物（例えば、ジフェニルメタンジイソシアネートの二量体や三量体、トリメチロールプロパンとトリレンジイソシアネートとの反応生成物、トリメチロールプロパンとヘキサメチレンジイソシアネートとの反応生成物、ポリメチレンポリフェニルイソシアネート、ポリエーテルポリイソシアネート、ポリエステルポリイソシアネートなど）等も用いることができる。なお、これら化合物を単独で用いてもよいが、複数選択して使用してもよい。 Further, examples of the araliphatic polyisocyanate include 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, ω, ω′-diisocyanate-1,4-diethylbenzene, 1,3- Examples include bis (1-isocyanate-1-methylethyl) benzene, 1,4-bis (1-isocyanate-1-methylethyl) benzene, 1,3-bis (α, α-dimethylisocyanatomethyl) benzene. In this embodiment, as the isocyanate compound, the above-exemplified aliphatic polyisocyanate, alicyclic polyisocyanate, aromatic polyisocyanate, dimer or trimer by araliphatic polyisocyanate are used. Reaction products or polymers (eg diphenylmethane diisocyanate dimers and trimers, reaction products of trimethylolpropane and tolylene diisocyanate, reaction products of trimethylolpropane and hexamethylene diisocyanate, polymethylene poly Phenyl isocyanate, polyether polyisocyanate, polyester polyisocyanate, etc.) can also be used. These compounds may be used alone or in combination.

図３（ａ）に示すように、それぞれ接着剤が付着した第１シート状物１４と第２シート状物１５は各髄部１２ａが外側になるように、即ち各表皮同士が接触するように、重ね合わせる。これにより接着剤付き積層体１６が得られる。重ね合わせる方法としては、第１シート状物の各表皮頂部と第２シート状物の各表皮頂部とを突き合わせてもよいが、図３（ａ）に示すように第１シート状物１４を構成する半割茎の各表皮頂部を第２シート状物１５を構成する半割茎の各表皮頂部とずらすことが、積層体の空隙が少なくなり、高い強度の積層材が得られる。次にこの接着剤付き積層体１６はプレスにより厚さが５〜２０％、好ましくは１０〜１５％減少するように圧締成形され、図３（ｂ）に示される積層材２０が得られる。即ち、圧締成形後の積層材２０は、積層体１６の厚さを５〜２０％圧縮した厚さになる。厚さが５％未満では、積層材の曲げ強度や剥離強度が低下する不具合があり、２０％を超えると低密度の積層材が得難い。上記圧締度により表面材のない積層材の密度は０．１〜０．３ｇ／ｃｍ³の範囲になる。プレスの温度は接着剤の種類により調整される。上述した水性高分子−イソシアネート系接着剤を用いた場合には、プレス温度５〜８０℃、好ましくは１５〜４０℃で所望の強度の積層材が得られる。プレス温度が５℃未満では接着剤の硬化時間が長くなり、８０℃を超えると積層材表面が変色するおそれがある。この積層材２０は、表装材と下地材との間に介在する中間材としての利用が見込まれる。 As shown in FIG. 3 (a), the first sheet-like material 14 and the second sheet-like material 15 to which the adhesive is respectively attached are arranged so that the medulla portions 12a are outside, that is, the respective epidermis are in contact with each other. , Superimpose. Thereby, the laminated body 16 with an adhesive agent is obtained. As a method of superimposing, each skin top part of the first sheet-like material and each skin top part of the second sheet-like material may be butted, but the first sheet-like material 14 is configured as shown in FIG. By shifting the tops of the half cuts of the half split stems from the tops of the tops of the half splits constituting the second sheet-like material 15, the gap of the laminate is reduced, and a high strength laminate is obtained. Next, the laminate 16 with adhesive is press-molded so that the thickness is reduced by 5 to 20%, preferably 10 to 15% by pressing, and the laminate 20 shown in FIG. 3B is obtained. That is, the laminated material 20 after the compression molding has a thickness obtained by compressing the thickness of the laminated body 16 by 5 to 20%. If the thickness is less than 5%, there is a problem that the bending strength and peel strength of the laminated material are lowered, and if it exceeds 20%, it is difficult to obtain a low-density laminated material. The density of the laminated material having no surface material is in the range of 0.1 to 0.3 g / cm ³ depending on the pressing degree. The temperature of the press is adjusted depending on the type of adhesive. When the above-mentioned aqueous polymer-isocyanate adhesive is used, a laminated material having a desired strength can be obtained at a press temperature of 5 to 80 ° C., preferably 15 to 40 ° C. When the press temperature is less than 5 ° C, the curing time of the adhesive becomes long, and when it exceeds 80 ° C, the surface of the laminated material may be discolored. The laminated material 20 is expected to be used as an intermediate material interposed between the cover material and the base material.

更に、図３（ｃ）に示すように、プレス前に接着剤付き積層体の片面又は両面に表面材１８を重ね合わせて圧締成形してもよい。このときのプレス温度及び積層体の厚さ減少割合は表面材のない積層体を圧締するときと同じである。これにより表面材付き積層材３０が得られる。この表面材としては、厚さ０．０１〜１ｍｍの熱硬化性樹脂シート、熱可塑性樹脂シート、単板、合板、布帛、紙、板紙、段ボール紙又は表面コート紙である。布帛には織物地、編物地、不織布、フェルトを含み、板紙にはボール紙を含む。この積層材３０の密度は表面材の種類に応じて０．１〜０．３ｇ／ｃｍ³の範囲になる。これらの表面材は積層材としての密度を増大させず、積層材が補強効果及び装飾効果を有するようになる。 Furthermore, as shown in FIG. 3 (c), the surface material 18 may be overlapped and pressed on one or both sides of the laminate with adhesive before pressing. At this time, the pressing temperature and the thickness reduction ratio of the laminate are the same as those when the laminate without the surface material is pressed. Thereby, the laminated material 30 with a surface material is obtained. The surface material is a thermosetting resin sheet, a thermoplastic resin sheet, a veneer, a plywood, a fabric, a paper, a paperboard, a corrugated paper, or a surface-coated paper having a thickness of 0.01 to 1 mm. The fabric includes woven fabric, knitted fabric, non-woven fabric, and felt, and the paperboard includes cardboard. The density of the laminated material 30 is in the range of 0.1 to 0.3 g / cm ³ depending on the type of the surface material. These surface materials do not increase the density as a laminated material, and the laminated material has a reinforcing effect and a decorative effect.

次に本発明の実施例を比較例とともに説明する。 Next, examples of the present invention will be described together with comparative examples.

＜実施例１＞
重量約１８ｇ、長さ３５ｃｍ、直径約２２ｍｍの乾燥した含水率７％のヒマワリ茎１５本を用意した。これらのヒマワリ茎の表皮には元来ワックスが存在していない。１５本のヒマワリ茎を温度８０℃、相対湿度１００％に維持された小型チャンバ（図示せず）に入れ、含水率が３０％になるまで維持した。これらのヒマワリ茎をチャンバから取り出し、それぞれ切断機により繊維方向に切開して２つに分割した。茎の含水率を調整したことにより、容易に茎を２分割できた。ヒマワリ茎は正確に二分割され、かつ茎髄部の切断面が平滑であった。得られた半割茎を２つの群に分け、各群の半割茎を各髄部が同一面になるようにかつそれぞれ繊維方向に配列した後、全ての半割茎の各端部を糸で結合して幅約３４ｃｍ、長さ３５ｃｍ、厚さ約１１ｍｍの２つのシート状物を形成した。 <Example 1>
Fifteen sunflower stalks having a weight of about 18 g, a length of 35 cm, and a diameter of about 22 mm and having a dry water content of 7% were prepared. These sunflower stalks are essentially free of wax. Fifteen sunflower stalks were placed in a small chamber (not shown) maintained at a temperature of 80 ° C. and a relative humidity of 100% and maintained until the moisture content was 30%. These sunflower stalks were taken out of the chamber, cut in the fiber direction by a cutting machine, and divided into two. By adjusting the moisture content of the stem, the stem could be easily divided into two. The sunflower stalk was precisely divided into two and the cut surface of the stalk pulp was smooth. Divide the obtained halves into two groups, and arrange the halves of each group so that each medulla is in the same plane and in the fiber direction, and then thread each end of all halves To form two sheet-like materials having a width of about 34 cm, a length of 35 cm, and a thickness of about 11 mm.

水性高分子−イソシアネート系接着剤を刷毛塗りにより２つのシート状物のそれぞれの両面に均一に塗布した。この水性高分子−イソシアネート系接着剤は商品名ＫＲ−１２０（光洋産業製）の主剤（９０質量％）と商品名ＡＰ（光洋産業製）の架橋剤（１０質量％）とからなる。塗布量は、シート状物の片面当り２０ｇ、両面合計で４０ｇであった。図３（ａ）及び（ｃ）に示すように、それぞれ接着剤を塗布した２つのシート状物を各髄部が外側になるように重ね合わせて、積層体１６を製造した後、この積層体の両面に厚さ０．２ｍｍの紙１８を重ね合わせて、厚さ２０ｍｍの単一の接着剤付き積層体を得た。この積層体を厚さ１７ｍｍのスペーサを設置した温度４０℃に維持したホットプレスに入れ、約１ＭＰａ（約１０ｋｇ／ｃｍ²）の圧力で４５分間圧締成形して幅約３４ｃｍ、長さ３５ｃｍ、厚さ１７ｍｍの板状積層材を得た。得られた積層材の密度は０．２ｇ／ｃｍ³であり、圧締成形により厚さが約１５％減少した。 The aqueous polymer-isocyanate adhesive was uniformly applied to both sides of each of the two sheets by brushing. This aqueous polymer-isocyanate-based adhesive is composed of a main agent (90% by mass) of trade name KR-120 (manufactured by Koyo Sangyo) and a cross-linking agent (10% by mass) of trade name AP (manufactured by Koyo Sangyo). The coating amount was 20 g per one side of the sheet-like material, and 40 g in total on both sides. As shown in FIGS. 3 (a) and 3 (c), two sheet-like materials each coated with an adhesive are overlapped so that each medulla portion is on the outside, and a laminate 16 is manufactured. A sheet 18 having a thickness of 0.2 mm was superimposed on both sides of the sheet to obtain a single laminate with an adhesive having a thickness of 20 mm. This laminate was put into a hot press maintained at a temperature of 40 ° C. with a spacer having a thickness of 17 mm, and pressed for about 45 minutes at a pressure of about 1 MPa (about 10 kg / cm ² ), about 34 cm wide, 35 cm long, A plate-like laminate having a thickness of 17 mm was obtained. The density of the obtained laminated material was 0.2 g / cm ³ , and the thickness was reduced by about 15% by pressing.

＜実施例２＞
実施例１とそれぞれ同じヒマワリ茎及び接着剤を用いて、実施例１と同様に積層体を製造した後、厚さ１９ｍｍのスペーサを設置した以外は実施例１と同様に積層体を圧締成形して幅約３４ｃｍ、長さ３５ｃｍ、厚さ１９ｍｍの板状積層材を得た。 <Example 2>
Using the same sunflower stalk and adhesive as in Example 1, a laminate was produced in the same manner as in Example 1, and then the laminate was press-molded in the same manner as in Example 1 except that a spacer having a thickness of 19 mm was installed. Thus, a plate-like laminated material having a width of about 34 cm, a length of 35 cm, and a thickness of 19 mm was obtained.

＜比較例１＞
実施例１とそれぞれ同じヒマワリ茎及び接着剤を用いて、実施例１と同様に積層体を製造した後、厚さ１４ｍｍのスペーサを設置した以外は実施例１と同様に積層体を圧締成形して幅約３４ｃｍ、長さ３５ｃｍ、厚さ１４ｍｍの板状積層材を得た。 <Comparative Example 1>
Using the same sunflower stalk and adhesive as in Example 1, a laminate was produced in the same manner as in Example 1, and then the laminate was press-molded in the same manner as in Example 1 except that a spacer having a thickness of 14 mm was installed. Thus, a plate-like laminated material having a width of about 34 cm, a length of 35 cm, and a thickness of 14 mm was obtained.

＜比較例２＞
実施例１とそれぞれ同じヒマワリ茎及び接着剤を用いて、実施例１と同様に積層体を製造した後、厚さ１９．４ｍｍのスペーサを設置した以外は実施例１と同様に積層体を圧締成形して幅約３４ｃｍ、長さ３５ｃｍ、厚さ１９．４ｍｍの板状積層材を得た。 <Comparative example 2>
Using the same sunflower stalk and adhesive as in Example 1, a laminate was produced in the same manner as in Example 1, and then the laminate was pressed in the same manner as in Example 1 except that a spacer having a thickness of 19.4 mm was installed. A plate-like laminate having a width of about 34 cm, a length of 35 cm, and a thickness of 19.4 mm was obtained by clamping.

＜実施例３＞
実施例１とそれぞれ同じヒマワリ茎及び接着剤を用いて、実施例１と同様に積層体を製造した後、圧締成形時の温度を５℃にした以外は実施例１と同様に積層体を圧締成形して幅約３４ｃｍ、長さ３５ｃｍ、厚さ１７ｍｍの板状積層材を得た。 <Example 3>
Using the same sunflower stalk and adhesive as in Example 1, a laminate was produced in the same manner as in Example 1, and then the laminate was prepared in the same manner as in Example 1 except that the temperature during pressing was 5 ° C. A plate-shaped laminate having a width of about 34 cm, a length of 35 cm, and a thickness of 17 mm was obtained by pressing.

＜実施例４＞
実施例１とそれぞれ同じヒマワリ茎及び接着剤を用いて、実施例１と同様に積層体を製造した後、圧締成形時の温度を８０℃にした以外は実施例１と同様に積層体を圧締成形して幅約３４ｃｍ、長さ３５ｃｍ、厚さ１７ｍｍの板状積層材を得た。 <Example 4>
Using the same sunflower stalk and adhesive as in Example 1, a laminate was produced in the same manner as in Example 1, and then the laminate was prepared in the same manner as in Example 1 except that the temperature during pressing was 80 ° C. A plate-shaped laminate having a width of about 34 cm, a length of 35 cm, and a thickness of 17 mm was obtained by pressing.

＜比較例３＞
実施例１とそれぞれ同じヒマワリ茎及び接着剤を用いて、実施例１と同様に積層体を製造した後、圧締成形時の温度を０℃にした以外は実施例１と同様に積層体を圧締成形して幅約３４ｃｍ、長さ３５ｃｍ、厚さ１７ｍｍの板状積層材を得た。 <Comparative Example 3>
Using the same sunflower stalk and adhesive as in Example 1, a laminate was produced in the same manner as in Example 1, and then the laminate was prepared in the same manner as in Example 1 except that the temperature during pressing was 0 ° C. A plate-shaped laminate having a width of about 34 cm, a length of 35 cm, and a thickness of 17 mm was obtained by pressing.

＜比較例４＞
実施例１とそれぞれ同じヒマワリ茎及び接着剤を用いて、実施例１と同様に積層体を製造した後、圧締成形時の温度を１００℃にした以外は実施例１と同様に積層体を圧締成形して幅約３４ｃｍ、長さ３５ｃｍ、厚さ１７ｍｍの板状積層材を得た。 <Comparative example 4>
Using the same sunflower stalk and adhesive as in Example 1, a laminate was produced in the same manner as in Example 1, and then the laminate was prepared in the same manner as in Example 1 except that the temperature during pressing was 100 ° C. A plate-shaped laminate having a width of about 34 cm, a length of 35 cm, and a thickness of 17 mm was obtained by pressing.

＜実施例５＞
実施例１とそれぞれ同じヒマワリ茎及び接着剤を用いて、実施例１と同じ２つのシート状物のそれぞれの茎表皮側の面のみに接着剤を均一に塗布した。それ以外は実施例１と同様に積層体を製造した後、積層体の両面に表面材を設けることなく実施例１と同様に積層体を圧締成形して幅約３４ｃｍ、長さ３５ｃｍ、厚さ１７ｍｍの板状積層材を得た。 <Example 5>
Using the same sunflower stalk and adhesive as in Example 1, the adhesive was uniformly applied only to the surface on the side of the stem epidermis of the same two sheets as in Example 1. Other than that, after manufacturing the laminate as in Example 1, the laminate was press-molded in the same manner as in Example 1 without providing a surface material on both sides of the laminate, and the width was about 34 cm, the length was 35 cm, and the thickness was A plate-shaped laminate having a thickness of 17 mm was obtained.

＜比較例５＞
重量約１８ｇ、長さ３５ｃｍ、直径約２２ｍｍの含水率７％のコウリャン茎１５本を用意した。これらのコウリャン茎の表皮には元来ワックスが存在している。１５本のコウリャン茎を実施例１と同じように温度８０℃、相対湿度１００％に維持された小型チャンバ（図示せず）に入れ、含水率が３０％になるまで維持した。これらのコウリャン茎をチャンバから取り出し、それぞれ切断機により繊維方向に切開して２つに分割した。茎の含水率を調整したことにより、容易に茎を２分割できたが、節の箇所は硬いままであった。コウリャン茎は正確に二分割しにくく、かつ茎髄部の切断面が平滑でなかった。これにより得られた半割茎を２つの群に分け、各群の半割茎を各髄部が同一面になるようにかつそれぞれ繊維方向に配列した後、全ての半割茎を糸で結合して幅約３４ｃｍ、長さ３５ｃｍ、厚さ約１１ｍｍの２つのシート状物を形成した。 <Comparative Example 5>
15 cucumber stems having a weight of about 18 g, a length of 35 cm, and a diameter of about 22 mm and a water content of 7% were prepared. Wax is inherently present in the skin of these sorghum stems. Fifteen sorghum stalks were placed in a small chamber (not shown) maintained at a temperature of 80 ° C. and a relative humidity of 100% as in Example 1, and maintained until the water content reached 30%. These cucumber stalks were removed from the chamber, cut in the fiber direction by a cutting machine, and divided into two. By adjusting the moisture content of the stalk, the stalk could be easily divided into two parts, but the nodes were still hard. The cucumber stalk was difficult to divide into two accurately, and the cut surface of the stalk pulp was not smooth. Divide the halves obtained in this way into two groups, arrange the halves of each group so that each medulla is in the same plane and in the fiber direction, and then join all the halves with a thread Thus, two sheet-like materials having a width of about 34 cm, a length of 35 cm, and a thickness of about 11 mm were formed.

水で２倍に希釈した自己乳化型ポリイソシアネート樹脂接着剤をスプレイコーティングすることにより２つのシート状物のそれぞれの両面に均一に塗布した。塗布量は、シート状物の片面当り２０ｇ、両面合計で４０ｇであった。接着剤以外は実施例１と同様に積層体を製造した後、この積層体の両面に厚さ０．２ｍｍの紙を重ね合わせて、厚さ２０ｍｍの単一の接着剤付き積層体を得た。この積層体を厚さ１７ｍｍのスペーサを設置した温度４０℃に維持したホットプレスに入れ、約１ＭＰａ（約１０ｋｇ／ｃｍ²）の圧力で４５分間圧締成形して幅約３４ｃｍ、長さ３５ｃｍ、厚さ１７ｍｍの板状積層材を得た。得られた積層材の密度は０．２１ｇ／ｃｍ³であり、圧締成形により厚さが約１５％減少した。 The self-emulsifying type polyisocyanate resin adhesive diluted twice with water was spray-coated to uniformly apply to both sides of the two sheet-like materials. The coating amount was 20 g per one side of the sheet-like material, and 40 g in total on both sides. A laminate was produced in the same manner as in Example 1 except for the adhesive, and then a 0.2 mm thick paper was laminated on both sides of the laminate to obtain a single laminate with an adhesive of 20 mm. . This laminate was put into a hot press maintained at a temperature of 40 ° C. with a spacer having a thickness of 17 mm, and pressed for about 45 minutes at a pressure of about 1 MPa (about 10 kg / cm ² ), about 34 cm wide, 35 cm long, A plate-like laminate having a thickness of 17 mm was obtained. The density of the obtained laminated material was 0.21 g / cm ³ , and the thickness was reduced by about 15% by pressing.

＜比較例６＞
比較例５とそれぞれ同じコウリャン茎及び接着剤を用いて、比較例５と同様に積層体を製造した後、厚さ１９ｍｍのスペーサを設置した以外は比較例５と同様に積層体を圧締成形して幅約３４ｃｍ、長さ３５ｃｍ、厚さ１９ｍｍの板状積層材を得た。 <Comparative Example 6>
Using the same sorghum stem and adhesive as in Comparative Example 5, a laminate was produced in the same manner as in Comparative Example 5, and then the laminate was press-molded in the same manner as in Comparative Example 5 except that a 19 mm thick spacer was installed. Thus, a plate-like laminated material having a width of about 34 cm, a length of 35 cm, and a thickness of 19 mm was obtained.

＜比較例７＞
図４に示すように、重量約１８ｇ、長さ３５ｃｍ、直径約２２ｍｍの含水率７％のコウリャン茎１５本を用意した。これらのコウリャン茎２の表皮２ａには元来ワックスが存在している。１５本のコウリャン茎を含水率を調整することなく、また繊維方向に切開することもなくそれぞれ繊維方向に配列した後、全てのコウリャン茎を糸で結合して幅約３４ｃｍ、長さ３５ｃｍ、厚さ２２ｍｍの単一のシート状物を形成した。水で２倍に希釈した自己乳化型ポリイソシアネート樹脂接着剤をスプレイコーティングすることによりシート状物の両面に均一に塗布した。塗布量は、シート状物の片面当り２０ｇ、両面合計で４０ｇであった。このシート状物の両面に厚さ０．２ｍｍの紙３を重ね合わせた後、この積層体を厚さ１９ｍｍのスペーサを設置した温度１５０℃に維持したホットプレスに入れ、約１ＭＰａ（約１０ｋｇ／ｃｍ²）の圧力で８分間圧締成形して幅約３４ｃｍ、長さ３５ｃｍ、厚さ１９ｍｍの板状積層材５を得た。得られた積層材の密度は０．１８ｇ／ｃｍ³であり、圧締成形により厚さが約１５％減少した。 <Comparative Example 7>
As shown in FIG. 4, 15 cucumber stems having a weight of about 18 g, a length of 35 cm, and a diameter of about 22 mm and a water content of 7% were prepared. Wax is originally present in the skin 2 a of these cucumber stems 2. After arranging 15 cucumber stalks in the fiber direction without adjusting the moisture content and without incising in the fiber direction, all the cucumber stalks are connected with yarns, and the width is about 34cm, length is 35cm, thickness A single sheet having a thickness of 22 mm was formed. The self-emulsifying type polyisocyanate resin adhesive diluted twice with water was spray coated to uniformly apply to both sides of the sheet-like material. The coating amount was 20 g per one side of the sheet-like material, and 40 g in total on both sides. After the paper 3 having a thickness of 0.2 mm was superposed on both surfaces of the sheet-like material, the laminate was placed in a hot press maintained at a temperature of 150 ° C. with a spacer having a thickness of 19 mm, and about 1 MPa (about 10 kg / The plate-like laminate 5 having a width of about 34 cm, a length of 35 cm, and a thickness of 19 mm was obtained by press molding at a pressure of cm ² ) for 8 minutes. The density of the obtained laminated material was 0.18 g / cm ³ , and the thickness was reduced by about 15% by pressing.

＜比較例８＞
実施例１と同じ含水率７％の乾燥したヒマワリ茎を用いた。このヒマワリ茎の含水率を調整することなく、実施例１と同じ接着剤を用いて、実施例１と同様に積層体を製造した後、この積層体を圧締成形して幅約３４ｃｍ、長さ３５ｃｍ、厚さ１７ｍｍの板状積層材を得た。 <Comparative Example 8>
The same dry sunflower stalk having a water content of 7% as in Example 1 was used. Without adjusting the moisture content of the sunflower stalk, a laminate was produced in the same manner as in Example 1 using the same adhesive as in Example 1, and then the laminate was press-molded to have a width of about 34 cm and a long length. A plate-like laminate having a thickness of 35 cm and a thickness of 17 mm was obtained.

＜比較試験と評価＞
実施例１〜５及び比較例１〜８の各積層材について、密度、剥離強度、曲げ強度、形状安定性、表面の変色度、表面の平滑度、反りやねじれの有無、耐衝撃性を調べた。剥離試験はＪＩＳＡ５９０８パーティクルボードの剥離強さ試験に準拠して行った。即ち寸法５０ｍｍ×５０ｍｍの試験片の両面に、引っ張り試験機にセットするためのジグであるアルミニウムブロックを接着し、引っ張り荷重速度２ｍｍ／ｍｉｎで試験片の表面に垂直に引っ張り、剥離破壊時の最大荷重を測定した。最大荷重を２５００ｍｍ²で除算して剥離強度とした。曲げ試験はＪＩＳＡ５９０８パーティクルボードの曲げ強さ試験に準拠して行った。即ち支点間の距離Ｌ（スパン）を試験体の厚さｔの１５倍とし、試験体の茎の方向をスパンの方向にして支点間に幅５０ｍｍ、長さ(Ｌ＋５０)ｍｍの試験体を配置した後、支点間の中心となる位置に平均速度１０ｍｍ／ｍｉｎで荷重をかけ、最大荷重Ｐを測定して、次式により曲げ強さを算出した。 <Comparison test and evaluation>
About each laminated material of Examples 1-5 and Comparative Examples 1-8, density, peel strength, bending strength, shape stability, surface discoloration, surface smoothness, presence or absence of warpage or twist, and impact resistance were investigated. It was. The peel test was performed according to the peel strength test of JIS A 5908 particle board. That is, an aluminum block, which is a jig for setting in a tensile tester, is bonded to both sides of a 50 mm × 50 mm test piece, and pulled perpendicularly to the surface of the test piece at a tensile load speed of 2 mm / min. The load was measured. The maximum load was divided by 2500 mm ² to obtain the peel strength. The bending test was performed in accordance with the bending strength test of JIS A 5908 particle board. That is, the distance L (span) between the fulcrums is set to 15 times the thickness t of the test specimen, and the test specimen having a width of 50 mm and a length (L + 50) mm is arranged between the fulcrums with the stem direction of the test specimen being the span direction. Then, a load was applied to the center position between the fulcrums at an average speed of 10 mm / min, the maximum load P was measured, and the bending strength was calculated by the following formula.

曲げ強さ＝（３ＰＬ）／（１００ｔ²）
形状安定性試験は、次の２つの方法で試験した。形状安定性試験(1)；２０ｃｍ×２０ｃｍの試験体の対角線の中央の変位を反り測定器（ＪＩＳＡ１４３７建築用内装ボード類の耐湿性試験方法の反り測定に使用するもの）を用いて、試験開始時、終了時、及び温度湿度の条件を変える毎に測定し、その最大変位の絶対値を反り量とした。温度湿度条件は、１０℃・１５％ＲＨ・１日間→４０℃・８０％ＲＨ・１日間→１０℃・１５％ＲＨ・１日間を３サイクル繰り返した。 Bending strength = (3PL) / (100t ² )
The shape stability test was performed by the following two methods. Shape stability test (1): Using a warpage measuring instrument (JIS A 1437 for measuring the warpage of the moisture resistance test method of interior boards for building) using the center displacement of the diagonal line of a 20 cm × 20 cm specimen, The measurement was performed at the start and end of the test and whenever the temperature and humidity conditions were changed, and the absolute value of the maximum displacement was taken as the amount of warpage. The temperature and humidity conditions were 10 ° C., 15% RH, 1 day → 40 ° C., 80% RH, 1 day → 10 ° C., 15% RH, 1 day, 3 cycles.

形状安定性試験(2)；３０ｃｍ×３０ｃｍの試験体を２０℃・５０％ＲＨに２日間置いた後、２０℃の雰囲気下で３０ｃｍの間隔をあけて互いに平行に配置した上枠と下枠の間に茎が鉛直になるように試験体を差し込み、試験体を鉛直状態にする。次いで鉛直の試験体の片面の表面が５０℃になるように、片側から３時間赤外線ランプをあてる。試験体の対角線の中央の変位をダイヤルゲージで測定し、照射開始から終了までの間の最大変位の絶対値を反り量とした。 Shape stability test (2): After placing a 30 cm × 30 cm specimen at 20 ° C. and 50% RH for 2 days, an upper frame and a lower frame arranged parallel to each other at an interval of 30 cm in an atmosphere of 20 ° C. The test specimen is inserted so that the stem is vertical between the two, and the test specimen is brought into a vertical state. Next, an infrared lamp is applied for 3 hours from one side so that the surface of one side of the vertical test specimen is 50 ° C. The displacement at the center of the diagonal of the specimen was measured with a dial gauge, and the absolute value of the maximum displacement from the start to the end of irradiation was taken as the amount of warpage.

表面の変色度は、圧締成形後の積層材表面における変色の有無を目視により調べた。表面の平滑度は、圧締成形後の積層材表面における平滑性を指触により調べた。更に反りやねじれは、圧締成形後の積層材における反り・ねじれの有無を目視により調べた。耐衝撃性試験は、ＪＩＳＡ１４０８「建築用ボード類の曲げ及び衝撃試験方法」の衝撃試験に従って行った。試験片（寸法３００ｍｍ×３００ｍｍ）を砂上全面支持によって水平に置き、球形おもり（直径約４１ｍｍ、質量２８６ｇ）を５０ｃｍの高さから試験片表面の中央部に自然落下させ、試験片の表面状態を目視により観察した。これらの結果を表１及び表２に示す。 The degree of discoloration on the surface was examined visually for the presence or absence of discoloration on the surface of the laminated material after press molding. As for the smoothness of the surface, the smoothness on the surface of the laminated material after press molding was examined by touch. Further, for warping and twisting, the presence or absence of warping and twisting in the laminated material after press-molding was examined visually. The impact resistance test was performed according to the impact test of JIS A 1408 “Bending and impact test method for building boards”. Place the test piece (dimension 300 mm x 300 mm) horizontally by supporting the entire surface of the sand, and drop the spherical weight (diameter: about 41 mm, mass: 286 g) from the height of 50 cm to the center of the test piece surface to change the surface condition of the test piece. It was observed visually. These results are shown in Tables 1 and 2.

表１及び表２から明らかなように、比較例１のヒマワリ茎を用いた積層材は、茎にひびが多く入るため剥離強度及び曲げ強度が低かった。また比較例２のヒマワリ茎を用いた積層材は、圧締の程度が小さく２つのシート状物同士の接着面積が小さいため比較例１のものよりも剥離強度及び曲げ強度が低く、耐衝撃性試験で表面材が剥離した。比較例３のヒマワリ茎を用いた積層材は、圧締温度が０℃で圧締時間が４５分と短かったため、接着剤が硬化しにくく、形状安定性(1)試験と耐衝撃性試験でそれぞれ表面材が剥離した。また比較例４のヒマワリ茎を用いた積層材は、圧締温度が１００℃であったため、積層材表面が変色するとともに積層材に反りが発生した。比較例５及び６のコウリャン茎を用いた積層材は、それぞれ、表皮のワックス成分が存在するにもかかわらず圧締温度を４０℃と低くしたため、接着力に劣り、比較例１のものよりも剥離強度及び曲げ強度が低く、形状安定性試験(1)及び(2)で表面材が剥離した。またこれらの積層材は、それぞれ、節の付近に茎間に隙間があり表面平滑性に劣り、耐衝撃性試験で表面材が剥離した。比較例７の積層材は、圧締温度が１５０℃と高かったため、剥離強度及び曲げ強度が高かったものの、積層材表面が変色するとともに積層材自体が繊維方向に直交する方向で緩やかに湾曲し反りが発生し、かつ茎の凹凸が積層材表面にそのまま出現した。比較例８の積層材は、含水率を調整しなかったため分割時に繊維方向に茎にひびが入り、正確に２つに分割できなかった。また髄部の切断面が平滑にならず凹凸が生じた。これらのため積層材の表面平滑性はやや不良であった。これに対して、実施例１〜５の積層材はその密度が０．１５〜０．２０と低いにもかかわらず、剥離強度及び曲げ強度が高く、形状安定性試験(1)及び(2)で表面材が剥離せず、積層材表面の変色はなく、平滑性も良好で、反りやねじれも無く、かつ耐衝撃性試験で表面材の剥離は見られなかった。

As is clear from Tables 1 and 2, the laminate using the sunflower stalk of Comparative Example 1 had low peel strength and bending strength due to many cracks in the stem. In addition, the laminated material using sunflower stems of Comparative Example 2 has a low degree of pressing and a small adhesion area between the two sheet-like materials, and therefore has lower peel strength and bending strength than those of Comparative Example 1, and impact resistance. The surface material peeled off in the test. The laminated material using the sunflower stalk of Comparative Example 3 had a pressing temperature of 0 ° C. and a pressing time of 45 minutes, so that the adhesive was hard to cure, and the shape stability (1) test and impact resistance test Each surface material peeled off. Moreover, since the laminated material using the sunflower stalk of Comparative Example 4 had a pressing temperature of 100 ° C., the surface of the laminated material was discolored and the laminated material was warped. The laminated materials using the sorghum stalks of Comparative Examples 5 and 6 each had a lower pressing temperature of 40 ° C. despite the presence of the wax component of the epidermis. The peel strength and bending strength were low, and the surface material peeled in the shape stability tests (1) and (2). In addition, these laminated materials had gaps between stems in the vicinity of the nodes and were inferior in surface smoothness, and the surface materials were peeled off in an impact resistance test. Since the laminate material of Comparative Example 7 had a high pressing temperature of 150 ° C., the peel strength and bending strength were high, but the surface of the laminate material was discolored and the laminate material itself was gently curved in the direction perpendicular to the fiber direction. Warpage occurred and stem irregularities appeared on the surface of the laminated material. In the laminated material of Comparative Example 8, the moisture content was not adjusted, so that the stem cracked in the fiber direction at the time of division, and could not be divided into two accurately. In addition, the cut surface of the medulla portion was not smooth and uneven. For these reasons, the surface smoothness of the laminate was somewhat poor. On the other hand, the laminates of Examples 1 to 5 have high peel strength and bending strength despite the low density of 0.15 to 0.20, and the shape stability tests (1) and (2) The surface material was not peeled off, the surface of the laminated material was not discolored, the smoothness was good, there was no warping or twisting, and the surface material was not peeled off in the impact resistance test.

本発明で得られた積層材は、低密度かつ高強度であって、表面性が良好であり、反りなどの変形が少ないため、襖、間仕切り、蓋として、又はこれらの芯材として利用することができる。 The laminated material obtained in the present invention has low density and high strength, good surface properties, and little deformation such as warpage, so that it can be used as a bag, a partition, a lid, or a core material thereof. Can do.

図１(ａ)は本発明の植物茎の斜視図であり、図１(ｂ)はその植物茎を２つに切開した半割茎の斜視図である。FIG. 1 (a) is a perspective view of a plant stem of the present invention, and FIG. 1 (b) is a perspective view of a half split stem in which the plant stem is cut into two. 図２は本発明のシート状物の斜視図である。FIG. 2 is a perspective view of the sheet-like material of the present invention. 図３(ａ)は本発明の積層体の横断面図であり、図３(ｂ)は本発明の積層材の横断面図であり、図３(ｃ)は本発明の表面材付き積層材の横断面図である。3A is a cross-sectional view of the laminate of the present invention, FIG. 3B is a cross-sectional view of the laminate of the present invention, and FIG. 3C is a laminate with a surface material of the present invention. FIG. 図４は比較例のコウリャン茎からなる積層材の横断面図である。FIG. 4 is a cross-sectional view of a laminated material made of a scallop stem of a comparative example.

符号の説明Explanation of symbols

１１植物茎
１２半割茎
１２ａ髄部
１２ｂ表皮
１３糸
１４，１５シート状物
１６積層体
１８表面材
２０，３０積層材 DESCRIPTION OF SYMBOLS 11 Plant stem 12 Half split stem 12a Pith part 12b Epidermis 13 Yarn 14,15 Sheet-like material 16 Laminated body 18 Surface material 20,30 Laminated material

Claims

複数本の乾燥したキク科植物茎の含水率を１０〜５０％に調整する工程と、
前記含水率を調整した複数本の植物茎をそれぞれ繊維方向に切開して２つに分割することにより複数本の半割茎を得る工程と、
前記複数本の半割茎を各髄部が同一面になるようにかつそれぞれ繊維方向に配列し半割茎を糸又はテープで結合して第１及び第２シート状物を形成する工程と、
前記第１及び第２シート状物に接着剤をそれぞれ付着させる工程と、
それぞれ接着剤が付着した前記第１シート状物と前記第２シート状物とを各髄部が外側になるように重ね合わせて接着剤付き積層体を得る工程と、
前記接着剤付き積層体を厚さが５〜２０％減少するように圧締成形して積層材を得る工程と
を含む積層材の製造方法。 Adjusting the moisture content of a plurality of dried asteraceae plant stems to 10-50%;
Obtaining a plurality of half-divided stems by incising the water content in a plurality of plant stems each in the fiber direction and dividing it into two;
A step of forming the first and second sheet-like materials by arranging the plurality of half-divided stems so that each medullary portion is in the same plane and respectively in the fiber direction and connecting the half-divided stems with a thread or tape;
Attaching an adhesive to each of the first and second sheet-like materials;
A step of superimposing the first sheet-like material and the second sheet-like material, each having an adhesive attached thereto, so that each medulla portion is on the outside to obtain a laminate with an adhesive;
A method of producing a laminated material, comprising: pressing the laminated body with an adhesive so as to reduce the thickness by 5 to 20% to obtain a laminated material.

第１シート状物を構成する半割茎の各表皮頂部を第２シート状物を構成する半割茎の各表皮頂部とずらして重ね合わせる請求項１記載の積層材の製造方法。 The method for producing a laminated material according to claim 1, wherein the tops of the half split stems constituting the first sheet-like material are shifted and superposed on the tops of the half split stems constituting the second sheet-like material.

接着剤付き積層体の片面又は両面に更に表面材を重ね合わせた後、圧締成形する請求項１又は２記載の積層材の製造方法。 The manufacturing method of the laminated material of Claim 1 or 2 which press-molds, after further superposing | stacking a surface material on the one or both surfaces of a laminated body with an adhesive agent.

表面材が熱硬化性樹脂シート、熱可塑性樹脂シート、単板、合板、布帛、紙、板紙、段ボール紙又は表面コート紙である請求項３記載の積層材の製造方法。 The method for producing a laminated material according to claim 3, wherein the surface material is a thermosetting resin sheet, a thermoplastic resin sheet, a veneer, a plywood, a fabric, a paper, a paperboard, a corrugated paper, or a surface-coated paper.

接着剤が水性高分子−イソシアネート系接着剤であって、接着剤付き積層体を５〜８０℃の温度で圧締成形する請求項１ないし３いずれか１項に記載の積層材の製造方法。 The method for producing a laminate according to any one of claims 1 to 3, wherein the adhesive is an aqueous polymer-isocyanate adhesive, and the laminate with the adhesive is press-molded at a temperature of 5 to 80 ° C.

キク科植物茎がヒマワリ、ヒメヒマワリ、ノコギリソウ、ヨモギ、ヒナギク、エゾギク、ベニバナ、キク、コスモス、ダリア、タンポポ又はフキである請求項１ないし５いずれか１項に記載の積層材の製造方法。 The method for producing a laminated material according to any one of claims 1 to 5, wherein the stem of the Asteraceae plant is sunflower, sunflower, yarrow, mugwort, daisies, sagebrush, safflower, chrysanthemum, cosmos, dahlia, dandelion or buffalo.

請求項１ないし６いずれか１項の方法により製造された積層材。 The laminated material manufactured by the method of any one of Claim 1 thru | or 6.