JP2008179065A - Method for manufacturing bed plate for floor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a bed plate for a floor which is excellent in compactness, smoothness and hardness of the surface, can hold excellent surface condition even by change in temperature, water absorption and moisture absorption when it is made to serve as a floor material, and is excellent in dimensional stability even when it is used for a floor material for floor heating. <P>SOLUTION: The method for manufacturing the bed plate for the floor comprises coating wood powder with an isocyanate adhesive or an aqueous adhesive, scattering it on the surface of plywood, and providing a molded layer by hot pressing. The method is characterized in that at least 90 wt.% of the wood powder is smaller than 100 mesh, and 100 pts.wt. wood powder is coated with 30-70 pts.wt. of the isocyanate adhesive in terms of a solid content, or with 35-70 pts.wt. of the aqueous adhesive in terms of a solid content selected from melamine resins, urea resins, urea-melamine resins and phenol resins. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing a floor plate excellent in surface density, smoothness, surface hardness, and the like.

Conventionally, floor coverings that have been directly bonded to the surface of plywood with surface decorative materials such as veneer and decorative paper have been used, but in recent years, wheel load on chairs, tables, bed legs, wheelchairs, or falling objects It is desired to provide a flooring in which unevenness due to local concentrated load is prevented. In order to achieve such a problem, it is necessary to increase the surface hardness of the base plate used for the flooring. For example, a hard wood veneer or particle board or medium density fiber board ( It has been proposed to use a laminate of MDF) or high-density fiberboard (HDF) as a floor base plate.
However, since the thickness of the particle board, MDF, and HDF is 2.0 mm or more, the half-cut ones are usually bonded in the thickness direction, which causes an increase in cost. Furthermore, particle board and MDF have a problem that they cannot be used around water because they absorb water and easily swell.

On the other hand, in Patent Document 1, a curable composition mainly composed of an oligoesterified cellulose material having a polymerizable double bond and an oligomer having a polymerizable double bond is sprayed on the surface of the wood board, and then this is hot-pressed. A method for producing a decorative board in which the curable composition and the wood board are bonded and integrated by plasticizing the cellulose material and crosslinking by polymerization of double bonds has been proposed. It is described that it has excellent surface hardness.
However, the oligoesterified cellulose material used in Patent Document 1 provides thermoplasticity and polymerizability by reacting a cellulose material such as wood flour with a dibasic acid anhydride and a monoepoxy compound having a polymerizable double bond. The wood powder used was not applicable to untreated wood flour.

Japanese Patent Laid-Open No. 2-145339

  The present invention provides a method for producing a floor base plate that is excellent in surface density, smoothness, and surface hardness, and that can maintain an excellent surface state due to temperature change, water absorption and moisture absorption when used as a flooring material. With the goal. Furthermore, it aims at providing the manufacturing method of the base plate for floors which was excellent in dimensional stability, when used for the flooring for floor heating.

That is, the present invention
(1) A method for producing a floor base plate, in which an isocyanate-based adhesive is applied to wood powder, and then sprayed on the surface of the plywood and provided with a molding layer by hot pressing, wherein 90 wt% or more of the wood powder is less than 100 mesh And the manufacturing method of the base plate for floors characterized by apply | coating 30-70 weight part of isocyanate adhesives in conversion of solid content with respect to 100 weight part of wood flour.
(2) A method for producing a floor plate for applying a water-based adhesive to wood flour, then spraying it on the surface of the plywood and providing a molding layer by hot pressing, wherein 90 wt% or more of the wood flour is less than 100 mesh A floor base comprising 35 to 70 parts by weight of a water-based adhesive selected from melamine resin, urea resin, urea / melamine resin, and phenol resin based on 100 parts by weight of wood powder. A manufacturing method of a board.
(3) The method for producing a floor plate according to (1) or (2), wherein hot pressing is performed at 110 to 180 ° C.
(4) The production of a floor plate according to (1) or (3), wherein the isocyanate-based adhesive is a monomer, dimer, trimer or a combination of diphenylmethane diisocyanate Method.
(5) The method for producing a floor plate according to any one of (1) to (4), wherein the molding layer has a thickness of 0.5 to 2.0 mm.
(6) The method for producing a floor plate according to any one of (1) to (5), wherein the surface of the molding layer is sanded.

In the production method of the present invention, since wood powder having 90 wt% or more and less than 100 mesh is used, there is no occurrence of crumbs or cracks on the surface due to temperature change, water absorption or moisture absorption, and surface fineness In addition, it is possible to provide a floor plate excellent in smoothness and surface hardness. Moreover, it is possible to easily provide a thin molding layer mainly composed of wood flour directly on the plywood in one step, even though wood flour having a very small surface area of less than 100 mesh is used. . Therefore, a flooring that does not cause unevenness or cracks on the surface of the surface decorative material even when a local concentrated load is applied or there is a fallen object without sticking particleboard or MDF to the plywood surface. It became possible to provide. Further, when an isocyanate-based adhesive is used as the adhesive, the temperature change and the dimensional change due to water absorption / moisture absorption are extremely small, so that a flooring suitable for floor heating can be provided.
Furthermore, even when using plywood with inferior surface smoothness, such as softwood plywood, which has been rapidly spreading recently due to the problems of depletion of south seawood used in plywood and price increases, There is also an advantage that a dense and smooth floor plate can be obtained.

The best mode for carrying out the present invention will be described below.
The floor base plate of the present invention is manufactured by applying an adhesive to wood powder, then spraying it on the surface of the plywood and hot pressing, but there is no particular limitation on the plywood used at this time, Hardwood plywood, softwood plywood, LVL, or the like can be used. There is no particular limitation on the number of plywood prices. The plywood in the present invention includes not only the above-described plywood but also a plywood that is partially combined with resin-impregnated paper, a reinforcing sheet, and the like.

  The wood flour used in the present invention is made of wood in chips and powders and is 90 wt% or more, preferably all less than 100 mesh. When using wood powder containing more than 10 wt% of 100 mesh or more, the wood powder swells due to water absorption from the surface of the molding layer, and the floor material surface may be crushed or cracked. It is not preferable. In addition, such a problem is considered to be because large wood flour swells more greatly than small wood flour even if the swelling rate is the same when the particle size of wood flour present on the surface of the molding layer is large. It is done. The wood powder used in the present invention is not a wood powder imparted with thermoplasticity or polymerizability by chemical modification as in Patent Document 1, but has a feature in that ordinary wood powder is used as it is. However, it is of course within the scope of the present invention to use wood flour imparted with properties other than thermoplasticity, such as fire resistance and dimensional stability.

The adhesive used in the present invention is an isocyanate-based adhesive or a water-based adhesive selected from melamine resins, urea resins, urea / melamine resins, and phenol resins. Among these, the use of an isocyanate-based adhesive is particularly preferable because there is little dimensional change due to temperature change of the floor base plate and water absorption / moisture absorption and no warpage occurs.
As the usage-amount of an adhesive agent, when using an isocyanate type adhesive agent, it is 30-70 weight part in conversion of resin solid content with respect to 100 weight part of wood flour, Preferably it is 40-60 weight part. On the other hand, when an aqueous adhesive selected from melamine resin, urea resin, urea / melamine resin, and phenol resin is used, it is 35 to 70 parts by weight, preferably 45 to 70 parts by weight in terms of resin solid content with respect to 100 parts by weight of wood flour. Parts by weight.
In the present invention, the amount of wood powder used is extremely small, and therefore it is necessary to use a considerably larger amount of adhesive than that used when producing a normal particle board. If the amount of adhesive used is less than the specified amount, the moldability is reduced and it is difficult to form a molding layer to be described later on the surface of the plywood. In addition, when hot pressing is performed, not only is it difficult to mold by flowing out from the side surface, but it is not preferable because it increases the cost. Furthermore, if the amount of the adhesive used is too large, the surface of the wood powder is completely covered with the adhesive, which causes a problem that it becomes impossible to bond the surface decorative material. In addition, when an aqueous adhesive is used, if the amount of the adhesive used is excessively increased, problems such as puncture due to the influence of moisture in the adhesive may occur.

  The isocyanate-based adhesive used in the present invention is not particularly limited as long as it has two or more isocyanate groups in the molecule. For example, diphenylmethane diisocyanate (MDI), tolylene diisocyanate (TDI) ), Xylene diisocyanate (XDI), hexamethylene diisocyanate (HDI), naphthalene diisocyanate (NDI), isophorone diisocyanate (IPDI), hydrogenated xylene diisocyanate, dicyclohexylmethane diisocyanate, tetramethylxylene diisocyanate, tetramethylene xylene diisocyanate, dimer acid diisocyanate, Norbornene diisocyanate, phenylene diisocyanate, etc., and these monomers, dimers, trimers and the like It can be used a combination of. In particular, diphenylmethane diisocyanate (MDI) monomers, dimers, trimers or combinations thereof are more preferred.

Now, the base plate for floors of this invention is manufactured in the following procedures using the above-mentioned plywood, wood flour, and adhesive.
First, an adhesive is applied to wood powder in which 90 wt% or more is less than 100 mesh to obtain wood powder coated with the adhesive. The method of applying the adhesive is not particularly limited, and examples thereof include a method of spraying the adhesive while rotating wood flour in the drum using an apparatus such as a drum blender.
Next, the applied wood flour obtained by the above method is sprayed on a plywood prepared in advance. Although there is no restriction | limiting in particular in the application quantity, What is necessary is just to select the quantity required in order to make the thickness of a shaping | molding layer into 0.5-2.0 mm suitably.

Thereafter, the molded layer is formed on the plywood by hot pressing. The hot pressing can be performed using a multi-stage press, a continuous press or the like. The conditions are preferably a temperature of 110 to 180 ° C., a pressure of 20 to 30 kg / cm ² , and a pressing time of 1 to 5 minutes. In the present invention, it is not preferable to apply pressure exceeding 30 kg / cm ² because the plywood itself is compressed rather than the molded layer because the wood powder coated with the adhesive is sprayed on the plywood and heat-pressed.
Thus, the floor plate of the present invention can be obtained, but it is preferable to sand the surface of the molding layer as necessary. By sanding the surface of the layer, the surface smoothness and the adhesion with the surface decorative material can be improved by exposing the wood flour to the surface.

  Moreover, it is preferable to make the thickness of the molding layer in the floor base plate of this invention into the range of 0.5-2.0 mm. By setting the thickness of the molding layer in the above range, it is possible to obtain a floor plate excellent in surface denseness, smoothness and surface hardness. On the other hand, if the thickness is too thin, the effect of providing the molding layer becomes insufficient, and conversely, even if it is too thick, an effect commensurate with it cannot be expected. Furthermore, when the molding layer is made too thick, it is necessary to increase the hot pressing temperature or to increase the hot pressing time for forming the molding layer. As a result, the plywood expands and the plywood shrinks after hot pressing. Therefore, there is a problem that warpage occurs.

  The floor board manufactured by the above-described method is used as a flooring material by pasting a conventionally known surface decorative material such as a decorative veneer (a veneer), a decorative paper, a synthetic resin decorative sheet, etc. Can do.

EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited to these. The following materials were used as raw materials.
<Wood flour>
W1 thunder flour (wood flour generated in the particle board manufacturing process, all of which is less than 100 mesh wood flour)
・ W2 wood chip (91.8 mesh wood powder is 81.8 wt%, less than 100 mesh wood powder is 18.2 wt%)
<Isocyanate adhesive>
A1 Diphenylmethane diisocyanate (MDI) (manufactured by Nippon Polyurethane Industry Co., Ltd., “Wood Cure 300”, resin solid content: 100 wt%)
<Melamine resin adhesive>
A2 Melamine resin adhesive (manufactured by Sunbake, “XL-01”, resin solid content: 63.4 wt%)
<Thermoplastic adhesive>
A3 acrylic / urethane mixed emulsion adhesive (Chuo Rika Kogyo Co., Ltd., “CR-500”, resin solid content: 57.3 wt%)

The measurement of performance evaluation shown in the following examples and comparative examples was performed by applying an adhesive (ethylene vinyl acetate emulsion) with a roll coater to the surface of a test piece obtained by cutting the obtained floor base plate into 120 mm × 270 mm, and then measuring the thickness. Was made by laminating a 0.15 mm polyolefin decorative sheet to make a flooring material by the following method.
<Impact resistance>
Based on JIS K5600 weight drop resistance (Du Pont type), a weight of 500 g was dropped onto a test piece from a height of 30 cm, and the surface hardness was evaluated by the depth of the dent.
<Type 2 immersion peel test>
In accordance with the JAS 2 immersion peeling test, after the test piece was immersed in warm water of 70 ± 3 ° C. for 2 hours and then dried at 60 ± 3 ° C. five times, the surface of the test piece was warped and warped. The state was evaluated visually. In addition, the result of this test evaluated the change of the surface state and dimensional change by water absorption and moisture absorption.
<Cryogenic repetition test>
In accordance with the JAS Cold Repeat B test, the test piece was left in an incubator at 80 ± 3 ° C. for 2 hours and then left in an incubator at −20 ± 3 ° C. for 2 hours to repeat the test at room temperature. After leaving it to reach, the surface of the test piece and the state of warping were visually evaluated. In addition, the result of this test evaluated the change of the surface state and dimensional change accompanying a temperature change.

Example 1
124 g / scale ² is applied to the surface of 12 mm thick hardwood plywood (5 ply) with 100 parts by weight of melamine resin adhesive (63.4 parts by weight in terms of solid content) applied to 100 parts by weight of sander powder. Then, hot pressing was performed at 130 ° C. and 25 kg / cm ² for 2 minutes. Thereafter, the surface was sanded with a sander to obtain a floor plate having a dense and smooth molding layer with a thickness of 0.67 mm. The floor material obtained by laminating a decorative sheet on the floor base plate thus obtained had an impact resistance of 0.25 mm, and showed an excellent surface state even after the second immersion test and the cold heat test. The results are shown in Table 1.

Comparative Examples 1 and 2
In the case of Comparative Example 1, 31.5 parts by weight (20 parts by weight in terms of solid content) of melamine resin adhesive on 100 parts by weight of wood chips on the surface of 12 mm thick hardwood plywood (5 plies), Comparative Example 2 In this case, the wood chips coated with 63 parts by weight (40 parts by weight in terms of solid content) are sprayed with 124 g / scale ² and hot-pressed at 150 ° C. and 25 kg / cm ² for 5 minutes, and then the surface is sanded with a sander machine. A floor base plate having a dense and smooth surface with a molding layer thickness of 0.70 mm was obtained. The flooring material obtained by pasting the decorative sheet on the floor base plate showed excellent properties of 0.26 mm. However, when two types of immersion test and cold repetition test were performed, the wood chip part Swelled and duck was generated on the entire surface. The results are shown in Table 1.

Examples 2, 3 and Comparative Examples 3-5
124 g / sq. ^{2 of} the sander powder having the adhesive shown in Table 1 applied to 100 parts by weight of the sander powder on the surface of a 12 mm thick hardwood plywood (5 ply) is sprayed and heated at 130 ° C. and 25 kg / cm ² for 2 minutes. Pressed. Thereafter, the surface was sanded with a sander to produce a floor plate. Table 1 shows the results of impact resistance, type 2 immersion dipping test, and cold heat repetition test of the flooring material obtained by laminating a decorative sheet on the floor plate obtained, together with the moldability.

As apparent from Table 1, according to the production method of the present invention according to Examples 1 to 3, the molded layer was easily formed on the plywood with a thickness of about 0.5 to 1.0 mm and the surface was dense. A smooth floor plate could be obtained, and excellent surface hardness (determined by impact resistance) was exhibited. Further, in the case of the two-type immersion test and the cold heat repetition test, some warping was observed, but a good surface state was maintained without occurrence of duck on the surface. On the other hand, the floor base plate according to Comparative Examples 1 and 2 uses a wood chip having a size exceeding the provisions of the present invention, so that a floor base plate having a smooth surface without any problem in formability is manufactured. Although the surface hardness was sufficient, when the type II immersion test or the cold heat repeated test was performed, not only did the warp occur, but the surface was greatly swollen and could not be used. When the usage-amount of the melamine adhesive concerning the comparative example 3 was below a regulation value, even if it hot-pressed, the surface became powdery and the molding layer could not be formed. On the contrary, in the case of the method using a large amount of the adhesive according to Comparative Example 4, the wood powder coated with the adhesive cannot be uniformly dispersed on the surface of the plywood because it is in a dumpling form. Thus, the molding layer could not be formed by flowing out from the side surface.
Furthermore, when a thermoplastic adhesive was used as the adhesive according to Comparative Example 5, a molding layer could not be formed even though the amount of the adhesive used was the same as in the other examples.

Examples 4-7, Comparative Example 6
Example 1 except that an isocyanate adhesive (diphenylmethane diisocyanate (MDI)) was used on the surface of a 12 mm thick hardwood plywood (5 ply) with respect to 100 parts by weight of sander powder and applied in the amount shown in Table 1. In the same manner, a floor plate was manufactured. Table 2 shows whether the formability is good and the performance of the flooring using the obtained floor plate.

  As is apparent from Table 2, 30 to 60 parts by weight (in terms of solid content) of diphenylmethane diisocyanate (MDI), which is the isocyanate adhesive of Examples 4 to 7, is used with respect to 100 parts by weight of the sander powder. Can easily produce a floor plate with a fine and smooth surface without any problems in formability, and the floor material produced using the obtained floor plate has excellent surface hardness and two-class immersion. Even after the test and the repeated heat and cold test, the surface was not crushed or warped, and could be used for floor heating. On the other hand, in the case of Comparative Example 6 in which the amount of adhesive used was small, a molding layer could not be formed.

Examples 8-10
With the formulation of Example 4, the amount of spraying was changed as shown in Table 3 to produce a floor plate. The results are also shown in Table 3.
As is clear from Table 3, in Example 8 where the amount applied was small and the molding layer was 0.5 mm or less, some duck was observed on the surface after the two-class immersion test and the cold repeated test. There was no warping of the object, and excellent dimensional stability was exhibited. Further, the surface hardness was low compared to some examples, but it was excellent in moldability and sufficiently practical.
On the other hand, in Examples 9 and 10 in which the thickness of the molding layer was 0.5 to 2.0 mm, the surface hardness, the two-class immersion test, and the cold heat repeat test showed excellent performance.

  According to the present invention, a high-performance floor base plate that is excellent in surface density, smoothness, and surface hardness, and that can maintain an excellent surface state even by temperature change, water absorption and moisture absorption, is one-stage and inexpensive. It became possible to provide to. Further, the method of the present invention has an advantage that it can be applied to softwood plywood. Furthermore, when an isocyanate adhesive is used as the adhesive, it has become possible to produce a flooring that can be suitably used for floor heating.

It is a schematic side view which shows the structure of the flooring using the base plate for floors of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Plywood 2 Molding layer 3 Base plate for floor 4 Surface decorative material 5 Floor material

Claims (6)

  After applying an isocyanate-based adhesive to wood powder, it is spread on the surface of the plywood and is a method for producing a floor base plate that is hot-pressed to provide a molding layer, wherein 90 wt% or more of the wood powder is less than 100 mesh, And the manufacturing method of the base plate for floors characterized by apply | coating 30-70 weight part of isocyanate adhesives in conversion of solid content with respect to 100 weight part of wood flour.   A method for producing a floor plate for applying a water-based adhesive to wood powder, then spraying it on the surface of the plywood, and providing a molding layer by hot pressing, wherein 90 wt% or more of the wood powder is less than 100 mesh, and Manufacture of a floor base plate characterized by applying an aqueous adhesive selected from melamine resin, urea resin, urea / melamine resin, and phenol resin to 35 to 70 parts by weight in terms of solid content with respect to 100 parts by weight of wood flour. Method.   The method for producing a floor plate according to claim 1 or 2, wherein hot pressing is performed at 110 to 180 ° C.   The method for producing a floor base plate according to claim 1 or 3, wherein the isocyanate adhesive is a monomer, dimer, trimer or a combination of diphenylmethane diisocyanate.   The method for producing a floor plate according to any one of claims 1 to 4, wherein the molding layer has a thickness of 0.5 to 2.0 mm. The method for producing a floor base plate according to any one of claims 1 to 5, wherein the surface of the molding layer is sanded.

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