JP2001269907A - Wooden floor material and method of manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wooden floor material with high dimensional stability of which foundation board is a medium density ligneous fiberboard (MDF). SOLUTION: On either obverse or reverse of the MDF, a number of grooves are formed to have a depth deeper than one half of thickness of the above MDF. The heart and the other side of the MDF are hardened under the condition that is penetrated polyurethane synthetic resin by coating polyurethane synthetic resin on the grooved side. The wooden floor material is constituted of the MDF foundation board that has the penetrated harden layer of synthetic resin on the both sides and has high dimensional stability, and a decorated surface board or veneer and a decollated sheet attached to both faces.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wooden flooring material having excellent dimensional stability and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, a medium-density wood fiber board (MDF) is provided on a surface or both front and back surfaces of a substrate made of a wood material such as plywood.
To form a composite board, and a decorative sheet such as a veneer, a synthetic resin decorative sheet, or printing paper is attached to the surface of the wood fiber board of the composite board, or a surface decorative layer is formed by painting or the like. It has been practiced to use a decorative board made of such a material as a flooring material. However, in such a flooring material, when a dynamic load is applied by a wagon or the like with casters, delamination occurs in the medium-density wood fiberboard. There is a possibility that the strength is reduced and the appearance of the surface is impaired.

[0003] For this reason, the present applicant has disclosed in
As described in Japanese Patent No. 279821, the substrate of the floor material is formed of a medium-density wood fiber board, and a permeation hardened layer of a polyurethane synthetic resin is provided on the surface layer portion of the medium-density wood fiber board. We have developed a wooden flooring with a wooden veneer attached.

[0004]

According to the above wooden flooring material, the surface layer of the medium-density wooden fiberboard forming the floorboard substrate is reinforced by the penetration hardened layer of polyurethane synthetic resin. Although delamination hardly occurs and impact resistance is improved, dimensional stability cannot be expected.

[0005] That is, medium-density wood fiber board has a large thickness expansion coefficient and a linear expansion coefficient in a water absorption test as compared with plywood widely used as a substrate for flooring, and therefore has a drawback in dimensional stability. Therefore, even if the surface layer of the medium-density wood fiberboard is reinforced with a permeation hardened layer of a polyurethane synthetic resin as described above and a wooden veneer veneer is adhered to the surface, The difference in shrinkage between the surface layer side of the material and the core layer portion or the back layer portion of the medium-density wood fiberboard becomes large, which causes a problem in dimensional stability such as warpage or swelling of the floor material. In addition, there is a problem in that moisture infiltrates from the back side of the medium-density wood fiber board, and the dimensional stability is further impaired.

[0006] The present invention has been made in view of such problems, and an object thereof is to achieve excellent dimensional stability despite the fact that a medium-density wood fiberboard is used as a substrate for flooring. It is an object of the present invention to provide a wooden flooring material capable of exhibiting water resistance and water resistance, and a method for producing the wooden flooring material.

[0007]

According to a first aspect of the present invention, there is provided a wooden flooring material comprising a medium specific gravity wooden fiberboard as a flooring substrate as a decorative sheet on the surface of the substrate. A medium-density wood fiber board forming the floor material substrate, on one of its front and back surfaces, １ ／ of the thickness of the medium-weight wood fiber board. Grooves having a depth reaching the above and penetrating over the entire width of the medium-density wood fiber board are provided at small intervals in the length direction, and these grooves and the surface on which the grooves are provided are provided. It has a structure in which a penetration hardened layer of a polyurethane synthetic resin is formed, and this penetration hardened layer is penetrated from the bottom of the groove to the other surface of the medium-density wood fiber board on the opposite side to the surface where the groove is provided. .

In the above wooden flooring material, the invention according to claim 2 is characterized in that the flooring material substrate is formed from the medium specific gravity wooden fiberboard and a plywood having a constant thickness adhered to the back surface of the medium specific gravity wooden fiberboard. It is characterized by having.

According to a third aspect of the present invention, there is provided the above-mentioned method for producing a wooden flooring material, wherein one half of the thickness of the medium specific gravity wood fiberboard is provided on one of the front and back surfaces of the medium specific gravity wood fiberboard having a constant thickness.
After forming grooves having a depth reaching the above and penetrating over the entire width of the medium-density wood fiberboard at small intervals in the length direction, a polyurethane-based synthetic resin is provided on the surface side on which the grooves are provided. By applying the liquid, the applied polyurethane-based synthetic resin liquid permeates into the medium-density wood fiber board from the surface and all the grooves, and a part of the surface is cured by curing the permeated polyurethane-based synthetic resin liquid. And a decorative sheet is adhered to the surface of a flooring substrate made of a medium-density wood fiber board on which the osmotic hardened layer is formed.

[0010]

The medium specific gravity wood fiber board forming the floor substrate is provided with a groove penetrating in the width direction of the medium specific gravity wood fiber board on the front or back surface at small intervals in the length direction. Since these grooves are formed to a depth reaching half or more of the thickness of the medium-density wood fiberboard, the penetration and curing of the polyurethane-based synthetic resin formed by permeating and curing from inside the grooves. The layer reaches not only the core layer of the medium-density wood fiber board but also the surface on the side opposite to the surface on which the grooves are provided. In addition, the expansion and contraction ratio between the front side and the back side becomes extremely small, and the difference in shrinkage ratio is almost eliminated, so that excellent dimensional stability in which warpage or swelling is hardly generated is exhibited.

Further, since the penetration hardened layer of the polyurethane synthetic resin is formed on both surfaces of the medium-density wood fiber board as described above, one of the surfaces is used as a surface and a decorative sheet is attached to the surface. By doing so, even if the decorative sheet is subjected to a dynamic load from a wagon with casters, there is no risk of delamination of the medium-density wood fiber board, and it has excellent impact resistance. In addition, the permeation hardened layer on the back side prevents moisture from infiltrating from the back side, and can constitute a floor material excellent in water resistance.

Further, since a polyurethane-based synthetic resin solution is applied to the surface of the medium-density wood fiberboard on which the large number of grooves are formed to form a permeation-hardened layer, it is different from forming means by immersion. Since the amount of the polyurethane-based synthetic resin solution used is small and economical, the above grooves are formed to have a depth that reaches 1/2 or more of the thickness of the medium-density wood fiber board. The synthetic resin liquid applied in these grooves can easily penetrate not only into the core layer of the medium-density wood fiber board, but also into the surface on the opposite side to the surface on which the grooves are provided. By simply applying the synthetic resin liquid to the surface, the penetration hardened layer of the synthetic resin liquid can be efficiently and reliably formed on both surfaces.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an example of a wooden flooring material. Medium specific gravity wood fiber board 1 having a thickness (about 8 mm), veneer attached to the surface of this medium specific gravity wood fiber board 1, and decorative sheet 2 having a thickness of 0.2 mm to 2 mm; Wood veneer 3 having a thickness of 0.2 mm to 2 mm and this wood veneer 3
The medium specific gravity wood fiber board 1 has a depth of at least の of the thickness of the medium specific gravity wood fiber board 1 from the front surface to the back surface. Grooves 5 are formed at small intervals in the longitudinal direction, and the hardening layers 6A and 6B of a polyurethane synthetic resin liquid are provided on the surface of the medium specific gravity wood fiber board 1 and all the grooves 5 described above. Further, on the back side of the medium specific gravity wood fiber board 1, a permeation hardened layer is formed by the permeation of the synthetic resin liquid from the groove 5.
6C is provided.

All of the grooves 5 formed in the medium-density wood fiber board 1 extend through the entire width of the medium-density wood fiber board 1 with its length direction directed in the width direction of the medium-weight wood fiber board 1. It is provided in the state where it was done. Further, in order to exhibit the necessary strength as a substrate of the wooden flooring material A, the groove width is formed to be a small width of 1 mm or less, and the pitch between the grooves is set to be 1 to 2 times the thickness of the medium specific gravity wood fiber board 1. Is formed. When the pitch between the grooves is twice or more the thickness of the medium-density wood fiber board 1, the synthetic resin liquid that penetrates in the groove 5 in a direction perpendicular to the thickness of the medium-density wood fiber board 1 is applied between the grooves 5, 5. It is not preferable because it is impossible to reach the middle portion and a weak portion is formed in the core layer portion of the medium-density wood fiber board 1.

Further, the above-mentioned synthetic resin liquid applied to the entire surface of the medium-density wood fiber board 1 forms the permeation hardened layer 6A over the entire surface layer portion of the medium-density wood fiber board 1,
The medium-density wood fiber board 1 is penetrated by the synthetic resin liquid penetrating in the direction parallel to the front and back surfaces of the medium-weight wood fiber board 1 through the groove 5.
The permeation hardened layer 6B is formed over the entire core layer. Further, the permeation hardened layer 6C is formed by the synthetic resin liquid that has permeated and diffused from the bottom of each groove 5 toward the back side of the medium-density wood fiber board 1. If the thickness of the medium-density wood fiberboard 1 remaining between the backside of the medium-density woodfiberboard 1 and the backside of the medium-weight woodfiberboard 1 is too thin, there is a risk that the medium-specific gravity woody fiberboard 1 for forming the flooring substrate may break.
If the thickness is too large, the synthetic resin liquid cannot penetrate from the bottom surface of the groove 5 to the back surface of the medium-density wood fiber board 1. The thickness of the medium-density wood fiber board 1 remaining between
mm.

The decorative sheet 2 to be adhered to the surface of the medium-density wood fiber board 1 is not limited to a veneer,
It may be a PC veneer, a printing paper, or a vinyl chloride sheet. It may be a coating layer of a paint.

In the wooden flooring material A thus configured,
The medium-density wood fiber board 1 forming the flooring substrate is provided with grooves 5
Is facing upwards, that is, the decorative sheet 2 made of a wooden decorative board or the like is stuck to the surface toward the front side, but as shown in FIG. While the back side is the back side, and the wood veneer 3 is attached to the back side,
The surface where the groove 5 is not opened may be used as a surface, and the decorative sheet 2 may be adhered to this surface. Further, as shown in FIGS. 3 and 4, a structure may be employed in which the cushion material 4 is directly adhered to the rear surface of the medium-density wood fiber board 1 without attaching the veneer veneer 3.

FIG. 5 shows another embodiment of the wooden flooring material according to the present invention. The medium specific gravity wood fiberboard provided with the multiple grooves 5 and the permeation hardened layers 6A to 6C as the flooring substrate as described above. 1A and a plywood 7 of constant thickness attached to the back of the medium-density wood fiber board 1A
It is formed from In this case, the medium specific gravity wood fiber board 1A and the plywood 7 are formed so that the sum of the thicknesses thereof is equal to the thickness of the medium specific gravity wood fiber board 1 in the above embodiment. The surface of this flooring substrate, that is, medium specific gravity wood fiber board 1A
The decorative sheet 2 is adhered to the surface of the plywood 6 in the same manner as in the above embodiment, and the cushioning material 4 is adhered to the back surface of the plywood 6 to constitute the wooden flooring material A.

In this wooden flooring material A, the direction of the multiple grooves 5 provided in the medium specific gravity wooden fiberboard 1A may be directed to the front side as shown in FIG. It may be directed to the back side as shown.

Next, an example of a method for manufacturing the wooden flooring material A will be described. First, a flooring material substrate is formed from a medium-density wooden fiberboard 1. At this time, when the floor material substrate is formed only by the medium specific gravity wood fiber board, the medium specific gravity wood fiber board having a thickness of about 8 mm is used, but when the floor material substrate is formed from the medium specific gravity wood fiber board and the plywood. A thin medium-density wood fiberboard is used for this.
As shown in FIG. 7, a plurality of grooves 5 having a depth reaching half or more of the thickness of the medium specific gravity wood fiber board 1 are formed on either of the front and back surfaces of the medium specific gravity wood fiber board 1. The wood fiber board 1 is formed at small intervals in the length direction.

The groove 5 can be formed by using a slitter in which thin circular blades 11 are fixed to the rotating shaft 10 at small intervals, and feeding the medium-density wood fiberboard 1 to the slitter. That is, when the medium-density wood fiberboard 1 is fed into the slitter, each circular blade 11 cuts a groove 5 having a groove width equal to the thickness of the circular blade 11 and a depth equal to the cutting depth of the circular blade 11. When the medium specific gravity wood fiber board 1 passes through the slitter, all the grooves 5 are in a state of penetrating over the entire width of the medium specific gravity wood fiber board 1.

After forming a large number of grooves 5 in the medium-density wood fiber board 1 in this manner, a polyurethane-based synthetic resin liquid is applied to the upper surface of the medium-weight wood fiber board 1 with the opening end of the groove 5 facing upward. The synthetic resin liquid is applied and penetrated into the inside of the medium-density wood fiber board 1 through the upper surface and the inside of the groove 5. As a means for applying the synthetic resin liquid to the upper surface of the medium-density wood fiber board 1, a brush, a spray, a roll coater or the like may be used.

The amount of the polyurethane-based synthetic resin liquid applied to the medium-density wood fiberboard 1 is required to form the above-mentioned permeation hardened layers 6A to 6C on both the front and back surfaces of the medium-density wood fiberboard 1 and the core layer. It is sufficient if the amount is too large, and if it is too large, the coating workability deteriorates and the cost increases, so that 10 to 15 g / 30.3 cm ² is desirable. Further, if the viscosity of the synthetic resin liquid is 1 poise or more, the permeability to the medium-density wood fiber board 1 deteriorates, so the viscosity is set to 1 poise or less, preferably 0.5 poise or less.

When the above synthetic resin liquid is applied to the upper surface of the medium-density wood fiberboard 1, the synthetic resin liquid enters each groove 5 from the opening end of the groove 5 while the grooves 5 The synthetic resin liquid applied to the flat upper surface other than the open end of the above-mentioned resin penetrates into the upper layer portion of the medium-density wood fiber board 1 from the upper surface to form a permeable layer over the entire surface layer portion. Further, the synthetic resin liquid that has penetrated into the grooves 5 penetrates from the vertical facing wall surfaces of these grooves 5 in a direction parallel to the front and back surfaces of the medium-density wood fiber board 1 and penetrates from the adjacent grooves 5, 5. The resin liquids are continuous with each other, and a permeation layer of the synthetic resin liquid is entirely formed on the intermediate layer (core layer) of the medium-density wood fiber board 1. Also, the synthetic resin liquid that has permeated and diffused from the bottom of each groove 5 toward the lower surface side of the medium specific gravity wood fiber board 1 reaches the lower surface of the medium specific gravity wood fiber board 1 and forms a continuous permeation layer on the entire lower surface. .

After the medium-density wood fiber board 1 is infiltrated with the polyurethane-based synthetic resin liquid, the medium-density wood fiber board 1 is heated to harden the permeable layer, as shown in FIG. The above-mentioned permeation hardened layers 6A to 6C are formed on the specific gravity wood fiber board 1. Next, the composite board is formed by laminating the decorative sheet 2 and the veneer veneer 3 on the front and back surfaces of the medium-density wood fiber board 1 with adhesives on the front and back surfaces of the floor board, respectively. Medium-density wood fiberboard 1 by pressure treatment
To obtain a wooden flooring material in which the decorative sheet 2 and the veneer veneer 3 are integrally adhered to the front and back surfaces with an adhesive.

The permeation layer of the synthetic resin liquid that has permeated the medium-density wood fiber board 1 may be cured at the time of heating by the hot press without performing a curing treatment in advance. In the case where the floor material substrate is formed of a medium-density wood fiber board and a plywood, the plywood is superimposed and the front surface (lower face) of the middle-specific wood fiber board treated as described above is bonded via the back surface (lower surface) adhesive. The decorative sheet 2 may be overlaid on the upper surface) and hot-pressed by a hot press to obtain a wooden floor material. Further, in any case, the cushion material 4 may be provided on the back surface.

Next, specific examples of the present invention and comparative examples will be described. [Example] After forming grooves having a depth of 5.4 mm at intervals of 10 mm with a slitter on one surface of a medium specific gravity wood fiberboard having a thickness of 7.9 mm, using a sponge roll coater, a polyurethane-based surface was formed. A synthetic resin solution (TC-23M, manufactured by Sink Kagaku Kogyo Co., Ltd.) is applied at a ratio of 15 g / 30.3 cm ² , and then, with the groove facing the back side, the medium specific gravity wood fiber board A veneer was laminated on the front surface and a veneer of the same tree type was laminated on the back surface with an adhesive, and hot-pressed by hot pressing to bond the veneer and veneer to the front and back surfaces of the medium-density wood fiber board. Further, while the surface of the veneer was painted, a cushioning material was attached to the back of the veneer to obtain a wooden flooring.

[Comparative Example] In the above embodiment, a 7.9 mm thick medium-density wood fiber board not subjected to groove processing and not coated with or impregnated with a synthetic resin solution was used. Then, the same veneer and veneer as in the above example were adhered to the veneer, the surface of the veneer was painted, and a cushion material was adhered to the back of the veneer to obtain a wooden floor material.

The wooden flooring material obtained in the above example and the wooden flooring material obtained in the comparative example were allowed to stand in a dryer room maintained at 80 ° C. for 3 hours, and the shrinkage in the length direction was measured every hour. . Table 1 shows the measurement results.

[0030]

[Table 1]

As is clear from the above table, the shrinkage rate of the wood flooring material of the example of the present invention is 1/3 as compared with the comparative example, and is excellent in dimensional stability.

[0032]

As described above, according to the wooden flooring material of the present invention, one of the thicknesses of the medium specific gravity wooden fiberboard is provided on one of the front and back surfaces of the medium specific gravity wooden fiberboard forming the flooring substrate. / 2 and a groove having a depth reaching at least / 2 and penetrating over the entire width of the medium-density wood fiber board is provided at small intervals in the length direction. Since a permeation hardened layer of polyurethane synthetic resin is formed in all the grooves, the permeation hardened layer is formed on the surface side of the medium-density wood fiber board where the grooves are provided, as well as the synthetic resin permeated from the grooves. The structure is also provided on the inside and on the opposite side of the medium specific gravity wood fiber board.Therefore, the entire medium specific gravity wood fiber board is reinforced by the permeation hardened layer of the polyurethane synthetic resin, and the overall shrinkage is extremely high. Small and almost no difference in expansion and contraction ratio between front and back sides Ri, in which warping or bulging has excellent dimensional stability hardly occurs.

Further, since the penetration hardened layer of the polyurethane-based synthetic resin is formed on both surfaces of the medium-density wood fiberboard as described above, one of the surfaces is used as a surface and a decorative sheet is attached to the surface. By doing so, even if the decorative sheet is subjected to a dynamic load from a wagon with casters, there is no risk of delamination of the medium-density wood fiber board, and it has excellent impact resistance. In addition, the permeation hardened layer on the back side prevents moisture from infiltrating from the back side, and can constitute a floor material excellent in water resistance.

According to the method for producing a wooden flooring material of the present invention, after forming a plurality of grooves on one of the front and back surfaces of a medium-density wood fiberboard having a constant thickness, a polyurethane-based synthetic fiber is formed on this surface side. Since the resin liquid is applied to form the permeation hardened layer, unlike the forming means by immersion, the amount of the polyurethane synthetic resin liquid used is small, and it is economical. The synthetic resin liquid that has penetrated into these grooves is applied to the inside of the core layer of the medium specific gravity wood fiber board (the inside ), Of course, can easily penetrate into the surface opposite to the surface on which the groove is provided, and a permeation hardened layer can also be formed on the surface. Just apply the synthetic resin liquid on one side of the board and combine it on both sides Since capable of forming a penetration cured layer of fat liquid, it is capable of producing a superior wood flooring dimensional stability efficiently and reliably.

[Brief description of the drawings]

1 is a longitudinal side view of a wooden flooring,

FIG. 2 is a longitudinal sectional side view showing a modified example thereof;

FIG. 3 is a longitudinal side view of a wooden flooring material in which a cushioning material is directly adhered to a back surface,

FIG. 4 is a longitudinal sectional side view showing a modified example thereof.

FIG. 5 is a vertical sectional side view of a wooden flooring using a flooring substrate composed of a medium-density wood fiberboard and plywood;

FIG. 6 is a longitudinal sectional side view showing a modified example thereof.

FIG. 7 is a simplified longitudinal side view of a state in which a groove is formed in a medium-density wood fiberboard,

FIG. 8 is a simplified vertical sectional side view of a medium-density wood fiber board on which a synthetic resin permeation hardened layer is formed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Medium specific gravity fiberboard 2 Decorative sheet 3 Wood veneer 4 Cushion material 5 Groove 6A-6C Penetration hardened layer 7 Plywood

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B32B 27/40 B32B 27/40 33/00 33/00 E04F 15/04 E04F 15/04 C 601 601E (72 ) Inventor Akihiro Takehara 1-Family, Inami-cho, Inami-cho, Higashi-Tonami-gun, Toyama Prefecture F-term (reference) 2B230 AA08 AA15 BA01 CB25 DA02 EA20 EB01 EB05 EB13 EB28 EB29 2B250 AA05 BA04 BA05 BA06 CA11 DA04 EA02 EA09 FA FA21 FA28 FA31 FA33 FA37 FA41 GA03 HA01 4F100 AK51B AP01A AP02C AP03B AR00A BA03 BA07 BA10A BA10C BA13 DC13B EA061 EC182 EH461 EJ08B EJ081 EJ301 EJ82B EJ821 GB08 HB31A JL04

Claims (3)

[Claims] 1. A wood flooring material obtained by sticking a decorative sheet on the surface of a flooring substrate made of a medium-density wood fiber board, wherein the medium-density wood fiber board forming the floor material board includes: Either half of the thickness of the medium specific gravity wood fiber board
Grooves having a depth reaching the above and penetrating over the entire width of the medium-density wood fiber board are provided at small intervals in the length direction, and the surface on the side where the grooves are provided and the surface A wooden flooring material characterized in that a polyurethane synthetic resin osmotic hardened layer is formed in all grooves. 2. The wood substrate according to claim 1, wherein the flooring material substrate is formed of a medium-density wood fiber board and a plywood having a constant thickness adhered to the back surface of the medium-density wood fiber board. Flooring. 3. A half-thickness of the medium-density wood fiberboard having a constant thickness on either one of the front and back surfaces thereof.
After forming grooves having a depth reaching the above and penetrating over the entire width of the medium-density wood fiberboard at small intervals in the length direction, a polyurethane-based synthetic resin is provided on the surface side on which the grooves are provided. By applying the liquid, the applied polyurethane-based synthetic resin liquid is permeated into the medium-density wood fiber board from its surface and all the grooves, and the permeated polyurethane-based synthetic resin liquid is cured to thereby obtain a medium-density wood fiber board. A method for producing a wooden flooring, comprising: forming a flooring substrate made of: and bonding a decorative sheet to a surface of the flooring substrate.