JP2000071373A - Moistureproof sheet, decorative plate and flash panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily produce a moistureproof processed product excellent in stability with the elapse of time with good productivity without generating the dimensional change or warpage of a moisture absorbing and discharging base material caused by the moisture in the adhesive used in the adhesion of the base material. SOLUTION: A hot-melt adhesive layer 2 is provided on the single surface of a base material sheet 1, if necessary, through a moistureproof layer 4 to form a moistureproof sheet of which the whole moisture permeability is 40 g/24 hrs.m2 or less. As necessary, a pattern layer 5 or a surface protective layer 6 is provided to the base material sheet 1 and, as necessary, a formaldehyde absorbent is added thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moisture-absorbing and releasing property of wood-based or plaster-based materials constituting building interior materials such as wall materials, construction members, and fittings, and surface materials of furniture, furniture, and housing equipment. The present invention relates to a moisture-proof sheet to be adhered to a surface of a base material to prevent dimensional change or warpage due to moisture absorption / release, and to use a decorative plate to which the moisture-proof sheet is adhered and a decorative sheet using the same. Flash panel.

[0002]

2. Description of the Related Art Materials such as wood and gypsum, which are widely used for building interior materials such as wall materials and fittings of houses, generally have moisture absorption and desorption properties, such as changes in temperature and humidity due to climate, and changes in front and back surfaces. It has the property of causing dimensional changes and warpage due to temperature and humidity differences, etc.
It is known that there are problems such as aesthetic problems, deterioration promotion due to intrusion of water from gaps, and problems such as the possibility of opening and closing operations of fittings and storage doors. .

[0003] It is known that the above phenomenon can be prevented by coating both sides of the base material with a moisture-proof material to prevent the flow of moisture between the outside air and the base material. I have. For example, Japanese Unexamined Patent Publication No. Hei 6-272455 discloses a method of adsorbing and releasing water by using non-permeable and non-permeable sheets laminated on the front and back of a wooden board as a plate material to be attached to both sides of a frame center of a flash panel. A technique for preventing warpage due to moisture has been disclosed.

The above-mentioned non-water-permeable and non-moisture-permeable sheet (moisture-proof sheet) is specifically a film or sheet made of a synthetic resin having low moisture permeability, such as polyethylene or polyvinyl chloride, or an aluminum foil. Metal foil or the like is used. However, these materials have difficulty in selecting an adhesive for directly bonding to a base material such as a wood material, and in the case of a synthetic resin film or sheet, the plasticizer contained in the synthetic resin is transferred. There are also disadvantages such as adhesion inhibition. Therefore, in many cases, a laminated sheet obtained by laminating these moisture-proof materials with paper or nonwoven fabric, which is advantageous for adhesion to a base material such as a wooden material, is used as the moisture-proof sheet.

The adhesive used for bonding the moisture-proof sheet to the base material has excellent adhesiveness to any of a hydrophilic base material such as wood or gypsum and paper or nonwoven fabric, and is inexpensive. In many cases, a water-based adhesive in the form of an emulsion or a paste, which is easy to handle, is selected. In addition, the surface to which the adhesive is applied may be applied to the moisture-proof sheet side, but in general, there is also a purpose of obtaining a strong adhesive force by permeation of the adhesive into the essentially porous base material, Is often applied to the base material side or both are used in many cases.

However, in the above-mentioned step of applying the adhesive to the substrate, the substrate, which is essentially water-absorbing, absorbs the water contained in the aqueous adhesive, thereby causing dimensional changes and warpage. There is a problem. Since this product contains water exceeding the equilibrium amount in the environment at the time of manufacture, water is gradually released (dehumidified) over time, and as a result, a dimensional change occurs. In particular, in the case of a surface material or the like in a flash panel, warpage may occur due to a difference in progress of drying of the front and back surfaces.

As a means for solving this problem, a method of using an adhesive containing no moisture, a method of applying the adhesive to the moisture-proof sheet side, drying the sheet sufficiently, and then attaching the adhesive to the substrate are conceivable. However, the former has difficulty in selecting an adhesive having excellent adhesiveness, and has problems such as an increase in the cost of the adhesive and deterioration of the working environment due to evaporation of an organic solvent and the like. On the other hand, the latter has problems such that a strong adhesive force cannot be obtained due to the permeation of the adhesive into the essentially porous substrate, and the surface properties and durability are reduced.

[0008] In addition, in any of the above methods, the adhesive must be applied immediately before the adhesion of the moisture-proof sheet to the base material. It is necessary to dry the water (solvent component) to some extent, and it is necessary to cure the adhesive after application until the adhesive is sufficiently dried and solidified.
Therefore, the number of processes is large as a whole, quality control such as the amount of application and the dry state is troublesome, and there is also a problem that productivity cannot be improved because it cannot be put into the next process immediately after sticking.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems in the prior art, and is intended to solve the problem of water content in an adhesive used for bonding to a moisture absorbing / releasing substrate. Provided is a moisture-proof sheet capable of easily producing a moisture-proof processed product having excellent stability over time without producing dimensional change or warpage of a base material with good productivity, and a decorative board and a flash panel using the same. It is intended to do so.

[0010]

The first moisture-proof sheet of the present invention is a moisture-proof sheet which is used for applying moisture-proof treatment by sticking to the surface of a moisture-absorbing and releasing substrate. It has a hot-melt adhesive layer on one side, and the moisture permeability of the entire sheet is 40 g / 24 hrs · m ² or less.

The second moisture-proof sheet of the present invention is the first moisture-proof sheet of the present invention, wherein the base sheet is a fibrous sheet and the hot melt adhesive layer has a moisture permeability of 40 g.
/ 24 hrs · m ² or less

The third moisture-proof sheet of the present invention is the first moisture-proof sheet of the present invention, wherein the base sheet is a fibrous sheet, and the base sheet and the hot-melt adhesive layer have a moisture permeability. It is characterized by being laminated via a moisture-proof layer of 40 g / 24 hrs · m ² or less.

[0013] The fourth moisture-proof sheet of the present invention is the first moisture-proof sheet of the present invention, wherein the moisture permeability of the base sheet is:
40 g / 24 hrs · m ² or less.

A fifth moisture-proof sheet according to the present invention is the moisture-proof sheet according to any one of the first to fourth inventions, wherein at least one of the base sheet, the hot melt adhesive layer, or the moisture-proof layer is It is characterized by containing a formaldehyde absorbent.

A sixth moisture-proof sheet according to the present invention is the moisture-proof sheet according to any one of the first to fifth aspects of the present invention, characterized in that a picture layer is provided on one or both sides of the base sheet. is there.

A seventh moisture-proof sheet according to the present invention is the moisture-proof sheet according to any one of the first to sixth aspects of the present invention, wherein the base sheet is opposite to the side on which the hot melt adhesive layer is provided. Is characterized by having a surface protective layer on the surface.

According to an eighth moisture-proof sheet of the present invention, in the seventh moisture-proof sheet of the present invention, at least one of the picture layer and the surface protective layer contains a formaldehyde absorbent.

The decorative plate of the present invention is a decorative plate comprising a moisture-absorbent substrate and a moisture-proof sheet having a moisture permeability of 40 g / 24 hrs · m ² adhered to the front and back surfaces of the substrate. And at least one of the moisture-proof sheet bodies attached to the back surface is the moisture-proof sheet according to any one of the first to eighth aspects of the present invention.

The flash panel of the present invention is characterized in that the decorative panel of the present invention is attached to both sides of the frame center.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION As shown in FIG. 1, a moisture-proof sheet according to the present invention basically comprises a base sheet 1 provided with a hot-melt adhesive layer 2 on one side. ,
The moisture permeability of the entire sheet including the base sheet 1 and the hot melt adhesive layer 2 is 40 g / 24 hrs · m ^2.
The gist of the present invention is as follows.

The base sheet 1 has such a degree that it does not hinder the work of adhering to the surface of the moisture-absorbing / desorbing base material 7 and does not hinder the practicality as a building material or various surface decorative materials after being stuck. Any material may be used as long as it is a sheet-like material having appropriate flexibility, mechanical strength, durability, etc., for example, thin paper, titanium paper, resin-mixed paper, resin-impregnated paper, paper-reinforced paper, bleached paper. Or woven paper made of various papers such as unbleached kraft paper, high-quality paper, glassine paper, linter paper, coated paper, inorganic paper, flame retardant paper, Japanese paper, and natural fibers, semi-synthetic fibers, synthetic fibers, or inorganic fibers Cloth or non-woven fabric, synthetic resin film such as polyethylene, polypropylene, polyester, polyvinyl chloride, polyvinylidene chloride, metal foil such as aluminum foil, copper foil, stainless steel foil, aluminum evaporated film, glass evaporated film, silicon oxide It may be used metals such as wearing film or inorganic material deposited film and the like.

In particular, as the base sheet 1, the above-mentioned paper,
When a fibrous sheet such as a woven or non-woven fabric is used, for example, adhesion to the frame center when used on the back of a decorative panel for a flash panel, or when used on the back of a decorative panel for a wall material of a building Inexpensive and excellent adhesion to wood materials, etc. There is an advantage that adhesion with an adhesive is easy.

Although the thickness of the base sheet 1 is not particularly limited, suitability for processing and handling, such as suitability for application of the hot melt adhesive layer 2 and suitability for adhering to the moisture absorbing / releasing base material 7, weight, price, etc. Is appropriately determined in consideration of For example, in the case of papers, it is usually selected from a range of a basis weight of about 10 to 50 g / m ² . When the base sheet 1 is made of a moisture-proof material to ensure the moisture-proof property of the entire moisture-proof sheet, it is necessary to have at least a sufficient thickness to satisfy the required moisture-proof property, for example, polyethylene resin or the like. In this case, at least 10 μm or more is required. The upper limit is determined from the suitability for processing and handling, the price, etc., and is usually 100 μm or less.

The hot melt adhesive layer 2 is formed on the base sheet 1
Is provided for the purpose of adhering the entire moisture-proof sheet of the present invention to the surface of the moisture-absorbing / releasing substrate 7, which is melted by heating to exhibit adhesiveness or tackiness, and then solidified by cooling. It is composed of a hot-melt adhesive mainly composed of a thermoplastic resin having a property of firmly adhering, and being added with an appropriate additive such as a tackifier or a plasticizer as needed. However, if the temperature at which the thermal adhesiveness is exhibited (thermal adhesive temperature) is too high, the loss of thermal energy is large and the danger of work is increased, and the thermal degradation of the substrate sheet 1 and the moisture absorbing / desorbing substrate 7 is caused. On the other hand, if the temperature is too low, the product is inferior in heat resistance, heat and humidity resistance, durability and the like. Therefore, in general, those having a heat bonding temperature in the range of about 60 to 150 ° C. are preferably used.

There are no particular restrictions on the type of hot melt adhesive used for the hot melt adhesive layer 2, and examples thereof include polyethylene resin, polypropylene resin, ethylene-vinyl acetate copolymer resin, and ethylene-ethyl acrylate copolymer. Various commercially available hot melt adhesives such as a coalescing resin type, an ionomer resin type, a polyamide resin type, a polyester resin type, and a polyurethane resin type can be appropriately used. In addition, not only a normal reversible type but also a reaction-curable hot-melt adhesive such as a moisture-curable type can be used. In the case of the moisture-curing type, in order to prevent a curing reaction in an unused state, as shown in FIG. 2, the moisture-proof release paper 3 is circulated on the surface of the hot-melt adhesive layer 2,
Immediately before adhering to the moisture absorbing / releasing substrate 7, the moisture-proof release paper 3 is peeled off.

In the case where the moisture-proof property of the entire desired moisture-proof sheet is ensured by the hot-melt adhesive layer 2, a material having a low moisture permeability is selected as the hot-melt adhesive. Hot melt adhesives of resin type, ethylene-vinyl acetate copolymer resin type, polyester resin type and the like are preferably used.
The thickness is, of course, at least a sufficient thickness to obtain the required moisture-proof property, at the time of sticking to an essentially porous moisture-absorbing / desorbing substrate, it was heated and melted. Since a part of the hot-melt adhesive layer 2 penetrates and impregnates the holes of the base material, the thickness of the hot-melt adhesive layer 2 after application is substantially reduced. It is necessary to design, and it is preferable that the thickness is at least 5 μm or more than the thickness required for achieving the target moisture-proof property. Specifically, although it depends on the type of the hot melt adhesive, a range of about 20 to 50 μm is generally preferable.

In place of providing the hot melt adhesive layer 2 with moisture proof property, the base sheet 1 may be made of a moisture proof material, or as shown in FIG. When the moisture-proof layer 4 made of a material having low moisture permeability is interposed between the melt adhesive layer 2 and the moisture-proof layer 4, the thickness of the hot-melt adhesive can be reduced to the minimum required for developing the necessary adhesive strength. In addition, there is an advantage that it is possible to prevent a variation in moisture-proof performance due to a difference in the state of penetration into the moisture-absorbing and releasing substrate due to the thermal bonding condition, and to easily produce a moisture-proof processed product with stable quality.

Examples of the moisture-proof layer 4 include synthetic resin films such as polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, and polytetrafluoroethylene, aluminum foil, copper foil, and stainless steel foil. And metal or inorganic vapor-deposited films such as a metal foil, an aluminum-deposited film, a glass-deposited film, and a silicon oxide-deposited film. However, a synthetic resin film is most preferable in terms of workability, durability, economy, and the like, and its thickness is generally preferably in the range of about 10 to 50 μm, though it depends on the type of the resin.

The moisture-proof sheet of the present invention is adhered to the surface of a moisture-absorbing and desorbing substrate to impart practically sufficient moisture-proof performance such as dimensional stability and warpage prevention property. Is 4
0 g / 24 hrs · m ² or less (however, measurement conditions are AST
ME 96). In a laminate made of a combination of materials having significantly different moisture permeability,
Since the moisture permeability of the entire laminate is approximately approximated by the moisture permeability of the constituent layer having the lowest moisture permeability, in the moisture-proof sheet having the above-described various structures, the base sheet, the hot melt adhesive layer or the moisture-proof layer Of which at least one layer has a moisture permeability of 40
g / 24 hrs · m ² or less.

By the way, as a typical moisture-absorbing and releasing base material for building materials, for example, a wood-based base material such as plywood, laminated wood, particle board, medium-density fiberboard, etc., an adhesive used in the production thereof is used. Because it contains formaldehyde, the free formaldehyde that is contained even after production is gradually released into the air from the surface of the base material. It can cause damage and is considered a problem in some. In order to solve this problem, in the moisture-proof sheet of the present invention, the base sheet 1, the hot-melt adhesive layer 2 or the moisture-proof layer 3 contains a formaldehyde absorbent to absorb formaldehyde emitted from the wood-based substrate. Can be removed.

The formaldehyde absorbent may be any substance capable of deodorizing and detoxifying it by reacting physically or chemically with formaldehyde. Specific examples include amino acids such as dicyandiamide and melamine. Compositions containing at least nitrogen compounds such as compounds, amides such as urea, barbituric acid and semicarbazide hydrochloride, amino acids such as glutamate, glycine and alanine, and hydrazine derivatives such as carbohydrazide and adipic dihydrazide. Can be suitably used. There is no particular limitation on the amount of formaldehyde absorbent used,
Generally, it is about 1 to ²⁰ g / m ² .

The formaldehyde absorbent may be contained in any of the constituent layers. However, when the formaldehyde absorbent is contained in the base sheet 1 which is in direct contact with the environmental air, the formaldehyde absorbent is radiated into the environmental air from the mouth of the decorative board. This is most preferable because the formaldehyde that has been absorbed can also be efficiently absorbed and removed.
In particular, when a fibrous sheet such as paper is used as the base sheet 1, the fibrous sheet is essentially porous, so that the substantial contact area with the environmental air is extremely large. This is extremely preferable because the efficiency of absorbing and removing formaldehyde in the air is enhanced.

The method of including a formaldehyde absorbent in each constituent layer is optional. For example, in the case of paper, a method of adding a formaldehyde absorbent to a pulp slurry at the time of papermaking, a method of applying or impregnating a paper containing the formaldehyde absorbent with paper after papermaking, or the like may be used.
In the case of a synthetic resin film, a method in which formaldehyde is kneaded with synthetic resin in a molten state to form a film, or a formaldehyde absorbent is added to a solution in which the synthetic resin is dissolved in an appropriate solvent, and a suitable support is provided. A method in which a solvent is volatilized by coating the film on the body and a method in which a formaldehyde absorbent is applied or impregnated on the formed film can be used.

In order to make the hot melt adhesive layer 2 contain a formaldehyde absorbent, a hot melt adhesive to which a formaldehyde absorbent is added in advance is prepared, or the hot melt adhesive is heated and melted at the time of hot melt coating. It depends on the method of adding a formaldehyde absorbent. However, the addition of a formaldehyde absorbent to the hot melt adhesive impairs the suitability for hot melt coating and the adhesiveness, and in particular, reduces the moisture resistance when the hot melt adhesive layer 2 is to be kept moisture resistant. In some cases, the addition of a formaldehyde absorbent to the hot melt adhesive layer 2 should be avoided.

As shown in FIG. 4, a design property can be imparted to the moisture-proof sheet of the present invention by applying a picture layer 5 having a desired pattern to the base sheet 1 as necessary. . When the base sheet 1 is opaque, the picture layer 5 is provided on the front side of the base sheet 1, that is, on the side opposite to the side on which the hot melt adhesive layer 2 is provided. When it is transparent or translucent, it may be provided on the back side of the base sheet 1, that is, between the base sheet 1 and the hot melt adhesive layer 2, or both may be used in combination.

The means for forming the picture layer 5 is not particularly limited.
For example, any conventionally known printing method such as a gravure printing method, an offset printing method, a flexographic printing method, a screen printing method, a letterpress printing method, an electrostatic printing method, and an ink jet printing method may be used. In addition to the printing method, any image forming means such as a hand-drawing method, a transfer method, a photographic method, an electrophotographic method, and a laser drawing method can be applied.

Further, by forming a surface protective layer 6 as necessary on the picture layer 5, surface properties such as abrasion resistance, water resistance and solvent resistance can be imparted, and the surface can have a desired gloss. It can also be adjusted to a state. The surface protective layer 6 is generally made of a transparent or translucent synthetic resin.
The laminate is formed by a film lamination method or a molten resin extrusion lamination method. In the case of the coating method, for example, a urethane resin, an alkyd resin, an acrylic resin, a polyester resin, a melamine resin, an epoxy resin, a fluorine resin, or the like is used. A curable resin such as a reaction curable type or an ionizing radiation curable type is often used. In the case of using a film lamination method or a molten resin extrusion lamination method, for example, a thermoplastic resin such as a polyolefin resin, an acrylic resin, a polyester resin, or a fluorine resin is used. The surface protective layer 6 may include a colorant, an extender, a filler,
Additives such as a gloss adjusting agent, a lubricant, a lubricant, and an antistatic agent are appropriately added.

A formaldehyde absorbent is added to the picture layer 5 and the surface protective layer 6 as needed. In particular, when the surface protective layer 6 contains a formaldehyde absorbent,
There is an advantage that formaldehyde can be efficiently absorbed and removed even from the environmental air which is in direct contact. In particular, when the surface protective layer 6 having a thickness of 5 μm or more is provided, even if the base sheet 1 contains a formaldehyde absorbent, the surface protective layer 6 inhibits the transmission of formaldehyde.
Since the effect of absorbing and removing formaldehyde from the ambient air is significantly reduced, it is preferable that the surface protective layer 6 contains a formaldehyde absorbent. When the surface protective layer 6 contains a formaldehyde absorbent, the surface protective layer 6
As a formaldehyde absorbent, it is preferable to use a hydrazine derivative having a property of reacting with a functional group in the resin and stabilizing the resin in order to prevent white turbidity, lower gloss, lower water resistance and the like.

In particular, when a hydrazine derivative having a plurality of hydrazino groups, such as carbohydrazide or adipic dihydrazide, is used, it acts as a cross-linking agent in the resin, and the surface protective layer 6 which is strong and has excellent physical properties is formed. There are benefits to be gained. In this case, the surface protective layer 6 is preferably made of an aqueous resin having excellent compatibility with the hydrazine derivative and containing a functional group capable of being crosslinked by the hydrazine derivative. It is preferable to use an aqueous emulsion resin composed of a resin, an acryl-styrene resin, a polyester resin, an alkyd resin, a urethane resin, a modified polyolefin resin, or the like.

The above-described moisture-proof sheet of the present invention is heat-pressed and bonded with the hot-melt adhesive layer 2 surface facing the moisture-absorbing / releasing substrate 7 surface, thereby providing the moisture-proof sheet of the present invention. A decorative board can be obtained. Heat and pressure bonding
Generally, a flat-pressure hot press method or a circular-pressure hot press method is used, but a method of applying a flat-pressure cold press or a circular-pressure cold press immediately after sufficiently heating a sheet with a hot roll or a hot plate or the like can also be used. .

Depending on the use of the decorative board, the moisture-proof sheet may be
When moisture absorption and desorption of the moisture absorbing and releasing substrate 7 occurs only on one side, for example, the moisture absorbing and releasing substrate 7 may be adhered to only one side of the moisture absorbing and releasing substrate 7, but this is a special example. In general, it is preferable that the decorative plate is attached to both surfaces of the moisture-absorbing / desorbing substrate 7 as shown in FIG. 5 in consideration of the possibility of moisture absorption and desorption during storage or transportation of the decorative board. In general, as shown in FIG. 5, a moisture-proof sheet provided with a picture layer 5 is provided on one side constituting an outer surface in a use state, and is attached to a frame core, a base core material, or the like. In many cases, a moisture-proof sheet not having the picture layer 5 is stuck to each other. However, for example, it is hard to be seen by a user such as a back panel of a flash panel for a storage door, or a makeup is separately applied on the moisture-proof sheet. In some applications and the like, a moisture-proof sheet having no picture layer 5 on both sides may be attached.

Incidentally, the decorative board of the present invention has a moisture absorbing and releasing base material 7
It is not essential that the moisture-proof sheet of the present invention be adhered to both the front and back surfaces. The moisture-proof sheet of the present invention is adhered to only one surface of the moisture-absorbing and releasing substrate 7, and the other surface has any moisture-proof property. It can also be configured by sticking a non-conductive sheet body. The moisture-proof sheet body has a moisture permeability of 40 g / cm 2 in order to achieve the purpose of preventing the moisture-absorbing and releasing substrate 7 from warping due to moisture absorption and release.
Any sheet may be used as long as the sheet is 24 hrs · m ² or less. Specifically, for example, a plastic film such as an olefin-based resin film or a polyester-based resin film, a metal foil such as a copper foil or an aluminum foil, a metal or inorganic vapor-deposited film, or the like.
Alternatively, a laminate including at least one of them may be used. In addition, the moisture-proof sheet may be provided with a decoration such as a pattern or embossed as necessary, and may be in any form as desired depending on the use of the decorative board. it can.

The flash panel of the present invention is completed by attaching the decorative plates 8 and 8 'described above to both sides of the frame core 9 in which square members are vertically and horizontally assembled as shown in FIG. In general, a moisture-proof sheet provided with a picture layer 5 is attached to at least one outer surface of the two decorative plates 8, 8 '. As the moisture-proof sheet provided with the picture layer 5, a general moisture-proof decorative sheet can be used, and any of the sixth to eighth moisture-proof sheets of the present invention can be used. It is also possible.

[0044]

<Example 1> A formaldehyde absorbent containing melamine as a main component was applied to a paper-to-paper reinforced paper having a basis weight of 30 g / m ² at a coating amount of 3 g / m ² after drying, and after drying, ethylene- A vinyl acetate copolymer resin-based hot melt adhesive was applied to a thickness of 30 μm to prepare a moisture-proof sheet of the present invention.
The moisture permeability of this moisture-proof sheet (ASTM E96) is 25
g / 24 hrs · m ² .

The above moisture-proof sheet was hot-press bonded to both sides of a 3 mm thick MDF substrate at a hot plate temperature of 100 ° C. This plate is adhered to both sides of a frame made of a 25 mm-thick particleboard square material vertically and horizontally via a vinyl acetate adhesive to produce an indoor door size flash panel. % RH, and the other side was subjected to a one-week warpage test under environmental conditions of 20 ° C. and 30% RH. The warpage was 1 mm or less per m.

The above moisture-proof sheet was adhered to only one side of the same 3 mm thick MDF base material by heat and pressure, and the amount of formaldehyde emission measured by the JIS desiccator method was 2.0 mg / l. .

[0047] in <Example 2> basis weight of 30 g / m ² paper between reinforced paper, dried and impregnated with formaldehyde absorbent consisting mainly of dicyandiamide impregnation amount 3 g / m ² after drying,
The surface is subjected to concealed solid printing and wood grain pattern printing by a gravure printing method using a nitrifying cotton-based ink, and further coated with a two-component curable urethane-based top coating agent after application in an amount of 4 g / m ^2.
After the surface protective layer was provided, an ethylene-vinyl acetate copolymer resin-based hot melt adhesive was applied on the back surface to a thickness of 30 μm to produce a moisture-proof sheet with a pattern of the present invention.

The moisture-proof sheet with the above-mentioned pattern was adhered to the surface of a 3 mm-thick MDF substrate, and the moisture-proof sheet without the pattern of Example 1 by hot-press bonding at a hot platen temperature of 100 ° C. A decorative plate of the present invention was produced. On the other hand, the non-patterned moisture-proof sheet of Example 1 was bonded to both surfaces of the same MDF substrate by hot-pressing to produce a non-patterned decorative board for the back surface.

On one side of the frame center made of a 25 mm-thick particleboard square bar, the face of the decorative board with the above-mentioned pattern on which the pattern is not provided is provided, and on the other face, the decorative board without the above-mentioned pattern is made of a vinyl acetate resin. The flash panel of the present invention was produced by bonding with an aqueous emulsion adhesive.

<Example 3> A formaldehyde absorbent containing melamine as a main component was applied to a paper-to-paper reinforced paper having a basis weight of 30 g / m ² to a coating amount of 3 g / m ² after drying, and after drying, a water-based surface was applied. An acrylic resin-based aqueous emulsion-type topcoat agent (with an epoxy-based curing agent) containing 10% solids content of carbohydrazide as a formaldehyde absorbent is printed with an abstract pattern by gravure printing using an acrylic ink. A coating amount of 7 g / m ² after drying was applied and dried and cured to form a surface protective layer. Thereafter, a polyethylene resin layer as a moisture-proof layer was melt-extruded and laminated to a thickness of 25 μm on the back surface, and an ethylene-vinyl acetate copolymer resin-based hot melt adhesive was applied to the polyethylene resin surface with a thickness of 15 μm.
m to prepare the moisture-proof sheet of the present invention. On the other hand, in the above-mentioned moisture-proof sheet, a moisture-proof sheet having a configuration in which printing of a pattern and formation of a surface protective layer were omitted was separately manufactured.

A 3 mm-thick MDF base material was hot-pressed on one surface with the above-mentioned moisture-proof sheet with a pattern and the other surface with the above-mentioned moisture-proof sheet without a pattern, thereby producing a decorative board of the present invention. The obtained decorative board is adhered to both sides of a 25 mm thick particle board frame core with a vinyl acetate resin-based aqueous emulsion adhesive, with the non-patterned moisture-proof sheet side facing the frame center side. The flash panel of the present invention was manufactured.

Example 4 The surface of a colored polyolefin-based resin film having a thickness of 50 μm was subjected to corona discharge treatment, and thereafter, a wood grain pattern excluding a conduit portion was printed by a gravure printing method using a urethane-based ink. Was melt-extruded to a thickness of 50 μm and laminated, and at the same time, embossing of a conduit pattern was performed, and a concave portion of the conduit was wiped and filled with a coloring agent, and then a urethane-based top coat was applied to the entire surface. Thereafter, an ethylene-vinyl acetate resin-based hot melt adhesive layer was formed on the back surface to a thickness of 20 μm to prepare a moisture-proof sheet of the present invention.

The above-mentioned moisture-proof sheet is stuck on one side of a 3 mm-thick MDF base material and the picture-free moisture-proof sheet described in the above Example 3 on the other side, thereby producing a decorative board of the present invention. did. The obtained decorative board is adhered to both sides of a 25 mm thick particle board frame core with a vinyl acetate resin-based aqueous emulsion adhesive, with the non-patterned moisture-proof sheet side facing the frame center side. The flash panel of the present invention was manufactured.

[0054]

Since the moisture-proof sheet of the present invention has a hot-melt adhesive layer on one side of the base sheet, there is no need to apply an adhesive when attaching the base sheet to the moisture-absorbing and releasing substrate. There is no dimensional change or warpage caused by the absorption of moisture by the substrate. Moreover, when attaching to the substrate, the surface of the moisture-proof sheet on the side of the hot-melt adhesive layer can be adhered to the surface of the substrate only by polymerization and heating, and then can be quickly fixed by cooling. Agent application process and drying process,
A curing step or the like is not required, and there is no need to control the amount of application and the dry state, and the adhesive can be immediately put into the next step after bonding. Therefore, an excellent effect that a moisture-proof processed product excellent in dimensional accuracy and without warpage can be stably and efficiently manufactured.

In particular, when the base sheet is formed of a fibrous sheet such as paper, the surface to which the moisture-proof sheet is adhered can be inexpensively bonded to another wood material or the like at a low cost. It can be easily bonded with a general-purpose adhesive such as a vinyl acetate emulsion adhesive which is excellent in adhesiveness. Also, for example, 2
Compared with a conventional moisture-proof sheet having a configuration in which a moisture-proof resin layer is sandwiched between sheets of paper, it is economical because there is no need to use two sheets of paper, and is advantageous in terms of strength.

In particular, when the base sheet is made of a moisture-proof material, or when the base sheet is made of paper, a moisture-proof layer is provided between the base sheet and the hot-melt adhesive. When the configuration is sandwiched, the type of hot-melt adhesive is not limited to the moisture-proof adhesive, the range of choice of the hot-melt adhesive is expanded, and the hot-melt adhesive is absorbed into the moisture-absorbing and releasing substrate. There is no need to worry about deterioration in moisture resistance.

Further, by providing a picture layer or a surface protective layer on the base sheet, or by including a formaldehyde absorbent in any one of the constituent layers, it is possible to simultaneously impart moisture-proof properties to the base sheet. , The design and abrasion resistance of the desired pattern,
Surface physical properties such as water resistance and formaldehyde absorption / removal function can be imparted.

A decorative board having such a moisture-proof sheet adhered to the front and / or back surface of the moisture-absorbing / desorbing substrate, and a flash panel using the decorative board, have a structure in which the moisture-absorbing / desorbing substrate is contained in the adhesive during the manufacturing process. , And not only does not cause dimensional change or warpage at the time of completion, but also a product that is stable over time can be obtained. Moreover, it has a multifaceted functionality to which any design property or surface physical property, formaldehyde absorption / removal function or the like is added as desired, and has an excellent advantage of being extremely useful as a building interior material and various surface decorative materials. Things.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing an embodiment of a moisture-proof sheet of the present invention.

FIG. 2 is a side sectional view showing an embodiment of the moisture-proof sheet of the present invention.

FIG. 3 is a side sectional view showing an embodiment of the moisture-proof sheet of the present invention.

FIG. 4 is a side sectional view showing an embodiment of the moisture-proof sheet of the present invention.

FIG. 5 is a side sectional view showing an embodiment of the decorative board of the present invention.

FIG. 6 is a side sectional view showing an embodiment of a flash panel of the present invention.

[Explanation of symbols]

 1 Base material sheet 2 Hot melt adhesive layer 3 Moisture-proof release paper 4 Moisture-proof layer 5 Picture pattern 6 Surface protective layer 7 Moisture-absorbing and releasing base material 8 Decorative board 9 ‥‥ frame center

 ────────────────────────────────────────────────── ─── Continued on the front page F term (reference) 2E109 AA07 AB04 CA02 CA07 CB03 EA05 2E162 CB22 CB24 CB25 CB30 CC03 CC05 CC06 CC08 CD11 CD12 CD13 CD14 CD15 CD16 CE08 4F100 AH07 AK22G AK68G AP03 AR00C AR00E AT00A AT00BA00 AT00BA00 AT02 BA07 BA10A BA10B BA10C BA10E CA30A CA30B CA30C CA30E CB03 DG01A DG01E GB08 HB00A HB00E JD04 JD04A JD04B JD04E JD15A JD15D JD15E JD16A JD16D JD16E JL00C JL00EJL04

Claims (10)

[Claims] Claims: 1. A moisture-proof sheet used for applying moisture-proof treatment by adhering to the surface of a moisture-absorbing and releasing substrate, comprising a hot-melt adhesive layer on one side of the substrate sheet, and A moisture-proof sheet having a moisture permeability of 40 g / 24 hrs · m ² or less. 2. The substrate sheet is a fibrous sheet, and the hot melt adhesive layer has a moisture permeability of 40 g / 24 hrs.
· M ² moistureproof sheet according to claim 1, characterized in that less. 3. The base sheet is a fibrous sheet, and the base sheet and the hot melt adhesive layer have a moisture permeability of 4.
^2. The moisture-proof sheet according to claim 1, wherein the moisture-proof sheet is laminated via a moisture-proof layer of 0 g / 24 hrs · m ² or less. 4. The substrate sheet has a moisture permeability of 40 g / 24.
The moisture-proof sheet according to claim 1, wherein the moisture-proof sheet is equal to or less than hrs · m ² . 5. The method according to claim 1, wherein at least one of said base sheet, said hot melt adhesive layer and said moisture-proof layer contains a formaldehyde absorbent.
The moisture-proof sheet according to any one of the above. 6. The moisture-proof sheet according to claim 1, wherein a picture layer is provided on one or both sides of the base sheet. 7. The moisture-proof sheet according to claim 6, wherein a surface protective layer is provided on a surface of the base sheet opposite to a side on which the hot melt adhesive layer is provided. 8. The moisture-proof sheet according to claim 7, wherein at least one of the picture layer and the surface protective layer contains a formaldehyde absorbent. 9. The moisture-absorbing and desorbing substrate has a moisture permeability of 4 on its front and back surfaces.
A decorative plate comprising a moisture-proof sheet having a thickness of 0 g / 24 hrs · m ² adhered thereto, wherein at least one of the moisture-proof sheets adhered to the front surface and the back surface is provided.
A decorative plate, characterized by being the moisture-proof sheet according to any one of the above. 10. A flash panel comprising the decorative panel according to claim 9 attached to both sides of a frame center.