JP2006123283A - Decorative sheet-laminated foam and top plate using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide decorative sheet-laminated foam using polyolefin hard foam of a reduced environmental load which is excellent in adhesion between the decorative sheet and a core material and can obtain a structure light in weight and high in rigidity and a top plate using the foam. <P>SOLUTION: In the decorative sheet-laminated foam, the decorative sheet is laminated/integrated on/with at least one side of a core material in which a surface material for suppressing foaming force in the inward direction generated when a rolled polyolefin resin expandable sheet is heated/expanded is laminated on both sides of a polyolefin resin foam sheet with individual bubbles oriented in the thickness direction. The decorative sheet is laminated/integrated on/with the surface material by an anchor effect. The top plate is formed by using the foam. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a decorative laminate laminated foam and a top board using the same, and more specifically, a decorative board using a polyolefin resin foam in which the major axis of bubbles constituting the foam is oriented in the thickness direction. The present invention relates to a laminated foam and a top plate using the same.

  Conventionally, a decorative panel is used for a top plate such as a table or a counter, and is mainly used for furniture, a housing equipment, an office appliance, or the like. These decorative panels, for example, as described in Patent Document 1, use a wood board material such as plywood, particle board or medium fiber board (MDF) as a core material as it is, a method of joining a decorative face material, Sandwich structure in which decorative face materials are bonded to each other via a board material such as plywood on a core material of a flash structure that combines a frame material and a paper honeycomb or resin foam of the same height (thickness) as the frame material Is used.

  As the decorative face material, melamine decorative board, decorative plywood, polyester decorative plywood, etc. are usually used. When the decorative face material is used only on one side, a phenol laminate (resin impregnated paper laminate) is used as the backing material. Body) is frequently used.

Japanese Utility Model Publication No. 6-17927

  However, when a paper honeycomb is used as the core material of the flash structure as described in Patent Document 1, the joint surface with the face material is in line contact when joining face materials such as a decorative face material and a backing material. Therefore, there is a problem that the bonding area is small compared to the actual face material area, and the bonding strength of the entire surface tends to be low.

  In addition, if a paper honeycomb or aluminum honeycomb, which has high compressive strength and is stable in quality, is used as the flash core material, it is possible to maintain the bending rigidity that functions as the top plate. In the top plate application, it is difficult to use an aluminum honeycomb in terms of cost. Furthermore, even in the case of using a paper honeycomb, it is common to use a paper material having a low compressive strength because of cost. The low adhesive strength of the joint surface between the decorative surface material and the core material does not necessarily maintain sufficient bending rigidity as a sandwich structure, and it is difficult to maintain sufficient rigidity that can be used as a top plate. There was a problem.

  In addition, in order to maintain sufficient rigidity, if a wood panel is used as the core material instead of the flash structure, the weight of the structure increases, so about assembly parts such as legs and mounting brackets that support the top plate, In addition to the problem that it is necessary to reinforce to support the load, and the problem that it is difficult to use for products with portable functions such as portable bulletin boards, shape change and corrosion due to water absorption of wooden materials are remarkable. There was a problem that it was easy to become. Further, depending on the material used, there is a problem that the recyclability is impaired and the environmental load is increased.

  An object of the present invention is a decorative laminate laminated foam using a polyolefin-based rigid foam that solves the above-mentioned problems and has a low environmental load, is excellent in adhesiveness between the decorative laminate and the core material, is lightweight and high in weight. An object of the present invention is to provide a decorative board laminated foam capable of obtaining a rigid structure and a top board using the same.

  The decorative board laminated foam according to claim 1 is a surface generated when the polyolefin resin foam sheet is heated and foamed on both surfaces of a polyolefin resin foam sheet in which individual cells are oriented in the thickness direction. A decorative foam laminated foam in which a decorative board is laminated and integrated on at least one side of a core material in which a face material for suppressing inward foaming force is laminated, and the decorative board has an anchor effect on the face material. It is characterized by being laminated and integrated.

  The decorative laminate laminated foam according to claim 2 is the decorative laminate laminated foam according to claim 1, wherein the decorative plate is a melamine decorative plate, and a phenol laminated plate is used as a backing material. To do.

  A decorative laminate laminated foam according to claim 3 is the decorative laminate laminated foam according to claim 1 or 2, wherein the decorative laminate has a flash structure in which a space surrounded by a frame member is filled with the core material. It is characterized by being laminated and integrated through a plywood between the core material and the core material.

  The top board according to claim 4 is characterized in that the decorative board laminated foam according to any one of claims 1 to 3 is used.

  Hereinafter, the present invention will be described in detail.

[Method for producing foam sheet]
The method for producing the foam of the decorative laminate laminated foam according to the present invention is not particularly limited, but is preferably a polyolefin resin and a dioxime compound, bismaleimide, divinylbenzene, an allyl polyfunctional monomer, (meth) acrylic polyfunctional 2 to 20 parts by weight of a pyrolytic chemical foaming agent such as azodicarbonamide is dispersed in 100 parts by weight of a modified polyolefin obtained by melt-mixing with at least one modification monomer selected from a monomer and a quinone compound Once this is formed into a sheet, a face material is fused to at least one side of the obtained foamable sheet original, and the original is heated above the decomposition temperature of the pyrolytic chemical foaming agent, This is foamed only in the thickness direction while suppressing the foaming force generated in the in-plane direction by the face material.

  By modifying the polyolefin resin as described above, it is possible to foam the foamed sheet at normal pressure and have anisotropy in the foaming direction even though the molded foam sheet has a low degree of crosslinking. Is possible.

  Here, the low degree of crosslinking means that the gel fraction is 25% or less. In general, the measurement of the gel fraction is expressed by a weight ratio between the initial weight of the sample and the sample obtained by dissolving the sample in hot xylene at 120 ° C. for 24 hours and drying the gel.

The polyolefin-based resin in the present invention is a (co) polymer of an olefinic monomer and is not particularly limited. For example, polyethylene such as low density polyethylene, high density polyethylene, and linear low density polyethylene, Homotype polypropylene, random type polypropylene, block type polypropylene and other polypropylene, polybutene, ethylene-propylene copolymer, ethylene-propylene-diene terpolymer, ethylene-butene copolymer, ethylene-vinyl acetate copolymer, It means one or more simple substances and mixtures selected from ethylene-based copolymers such as ethylene-acrylic acid ester copolymers. The “(co) polymer” mentioned here means “polymer” or “copolymer”.

  The polyolefin-based resin may be blended with other resins such as polystyrene and styrene-based elastomer within a range of less than 30% by weight. However, if it exceeds 30% by weight, not only the characteristics of the polyolefin (light weight, chemical resistance, flexibility, elasticity, etc.) cannot be exhibited, but it may be difficult to ensure the melt viscosity necessary for foaming. As the polyolefin-based resin in the present invention, one or more of polyethylene and polypropylene are particularly preferably used.

  The pyrolytic chemical foaming agent is not particularly limited as long as it generates a decomposition gas by heating, and the following are exemplified. Azodicarbonamide, benzenesulfonyl hydrazide, dinitrosopentamethylenetetramine, toluenesulfonyl hydrazide, 4,4-oxybis (benzenesulfonyl hydrazide). These may be used alone or in admixture of two or more. Of these, azodicarbonamide is preferably used.

  As a method for shaping the foamable sheet material, methods generally used in plastic molding, such as press molding, blow molding, calendering, injection molding, etc., can be applied in addition to extrusion molding. However, the method of directly shaping the foamable resin composition discharged from the screw extruder is preferred from the viewpoint of productivity. In this case, a continuous foam sheet having a constant width can be obtained.

  The method of laminating the face material on at least one surface of the foam sheet is not particularly limited. For example, (a) a method in which the face material is pasted on a foam sheet that has been cooled and solidified while heating; Examples thereof include a method in which the foamable sheet is heated until it is in a molten state and this is heat-sealed to the face material, and (c) a method in which the face material is bonded to the foamable sheet with an adhesive.

  In order to ensure the thickness accuracy of the foamable composite sheet, that is, the core material, the method (a) or (c) is most preferable. Examples of the method (b) of heat fusion include, for example, in a state where a face material is lightly laminated on at least one surface of a molten foam sheet immediately after being extruded from a T-die, and these are opposed cooling rolls. A method in which the two are passed through and integrated with the pressing force of the roll is preferable. In addition, when the original sheet and the face material are laminated and integrated as described above, when both the raw material and the face material are peeled at the interface between the two, both materials are broken to such a degree that material destruction occurs at a high rate. Means a state in which is fixed.

  The face material used to regulate the foaming direction of the polyolefin resin foam sheet is a sheet material having a thickness of less than 1 mm. Specific examples are as follows.

1) Glass cloth A typical example of a glass cloth is one produced by weaving a surface mat or glass roving obtained by making glass fibers. The surface mat may contain a binder for binding the short glass fibers. The binder is not particularly limited as long as the tensile strength of the face material satisfies the above range. For example, thermoplastic resins such as polyvinyl alcohol, saturated polyester, and acrylic resin, and heat such as epoxy resin and unsaturated polyester are used. A curable resin is mentioned.

2) Carbon mat 3) Woven fabric, non-woven fabric, cold water, needle punch Examples of organic fibers constituting these include polyester fiber, acrylic fiber, nylon fiber, carbon fiber, and aramid fiber. There are also natural fibers such as cotton and kenaf.

4) Papers Examples of papers include pulp (cellulose content of 90% or more).

5) Thin iron-based metal sheet Examples of the thin iron-based metal sheet include a molten galvanized steel sheet, a galvanized aluminum alloy steel sheet, and a stainless steel sheet.

6) Thin nonferrous metal sheet Examples of the thin nonferrous metal sheet include an aluminum plate, a titanium plate, and a copper plate.

  In the present invention, the decorative board is laminated and integrated with the face material by an anchor effect. Here, the anchor effect has a fine uneven shape on the surface of the face material, and adhesive, molten resin, etc. enter the uneven shape and get caught by the overhang shape (rib shape) or mesh shape of the uneven shape. This means the effect of being firmly integrated.

  Therefore, the face material in the present invention is not particularly limited as long as it provides the anchor effect, but among them, glass cloth, carbon mat, paper, nonwoven fabric, and the like are preferable in that they provide an excellent anchor effect.

  In addition, when the face material has an anchor effect as described above, when a solvent is used for the adhesive, the effect of volatilizing the solvent component at a high speed can be exerted by the function of the uneven shape of the surface. , Curing time can be shortened.

  The thickness of the face material is preferably 1 mm or less, more preferably 0.3 mm or less. If the thickness is 1 mm or more, the flexibility of the face material is impaired, and it becomes difficult to continuously apply the face material to the core material, and it becomes difficult to heat the foamable sheet through the face material, so the face material The foamable sheet does not fuse uniformly and the cell structure becomes non-uniform due to peeling or the like. Moreover, when the thickness is 0.3 mm or less, it may be difficult to obtain the unevenness that provides the anchor effect as described above.

  Foaming of the original foamable sheet is usually performed in a temperature range not lower than the decomposition temperature of the pyrolytic chemical foaming agent and not higher than the thermal decomposition temperature of the thermoplastic resin. In particular, as a continuous foaming device, in addition to a take-off foamer that foams while taking out the foam on the outlet side of the heating furnace, a belt-type foamer, a vertical or horizontal foaming furnace, a hot air thermostat, etc., or in a hot bath Foaming oil baths, metal baths, salt baths, etc. are used.

  The foam produced by the above-described method has the long axis of the cell diameter arranged in the thickness direction and exhibits physical properties excellent in compressive strength.

  The decorative laminated board foam of the present invention is obtained by using the above foam as a core material, and a decorative board is laminated and integrated on at least one surface of the core material. That is, the decorative board laminated foam may have a decorative board laminated on both sides of the core material, or a backing material laminated on one side.

  The decorative board is not particularly limited, and examples thereof include a melamine decorative board, a decorative plywood, and a polyester decorative plywood.

  The backing material is not particularly limited, and examples thereof include a phenol laminate, a melamine decorative board, a decorative plywood, a polyester decorative board, a plywood, and a metal board.

  In the above, when the decorative board is a melamine decorative board and a phenol laminate is used as the backing material, it is preferable in terms of excellent balance between lightness and rigidity, and excellent scratch resistance of the decorative board. A decorative laminate laminated foam can be obtained.

  A method for laminating and integrating the decorative board is not particularly limited, but a general method is to bond the core material and the decorative board via an adhesive (including a hot melt adhesive).

Although it does not specifically limit as an adhesion | attachment method, It is preferable to press-process using a cold press machine etc. The press pressure is usually about 1 to 10 kgf / cm ² and the pressurization time is about 2 hours. When the pressing pressure is 1 kgf / cm ² or less, it becomes difficult to press the entire surface on average, and uneven adhesion or warpage may easily occur. Further, if the press pressure is 10 kgf / cm ² or more, the core material itself may be crushed by a compressive load.

  Examples of the adhesive include, but are not limited to, vinyl acetate resin emulsion adhesive, acrylic emulsion adhesive, vinyl acetate copolymer emulsion adhesive, polyvinyl alcohol adhesive, vinyl acetate resin mastic adhesive, dope cement, monomer cement , Vinyl chloride resin adhesive, EVA hot melt adhesive, polyamide hot melt adhesive, polyester hot melt adhesive, thermoplastic rubber adhesive, synthetic rubber latex adhesive, urethane hot melt adhesive, synthetic rubber Examples thereof include a SIS hot melt adhesive, a chloroprene rubber adhesive, a natural rubber adhesive, a urea resin adhesive, a melamine resin adhesive, a phenol resin adhesive, an epoxy resin adhesive, and a polyurethane adhesive.

  The decorative laminate laminated foam of the present invention has a flash structure in which the core material is filled in a space surrounded by a frame material, and is laminated and integrated through a plywood between the decorative plate and the core material. In that case, it is preferable in that the rigidity of the resulting structure is further improved, and a decorative board laminated foam more suitable as a top board can be obtained.

  In the flash structure, when an increase in weight is permitted, a wood frame having a predetermined height may be inserted into a space surrounded by the frame material. In this case, the rigidity of the obtained structure is further improved.

  A face material for suppressing the foaming force in the in-plane direction generated when the polyolefin resin foam sheet is heated and foamed on both surfaces of a polyolefin resin foam sheet in which individual cells are oriented in the thickness direction. A decorative foam laminated foam in which a decorative board is laminated and integrated on at least one surface of a core material laminated with the decorative board, wherein the decorative board is laminated and integrated with the face material by an anchor effect. Therefore, it is a decorative laminate laminated foam using a polyolefin-based hard foam with a small environmental load, and has excellent adhesion between the decorative plate and the core material, and can obtain a lightweight and highly rigid structure. A laminated foam can be provided.

  When the decorative board is a melamine decorative board and a phenol laminate is used as the backing material, the balance of lightness and rigidity is excellent, and the scratch resistance of the decorative board is also excellent, and the above effect is more certain. It will be a thing.

  In addition, when the space surrounded by the frame material has a flash structure in which the core material is filled and is laminated and integrated via a plywood between the decorative board and the core material, the resulting structure The rigidity is further improved, and the above effect is further ensured.

  The top plate of the present invention is characterized in that the decorative plate laminated foam is used, so that a top plate exhibiting the same effects as described above can be obtained. For this reason, it is possible to simplify assembly parts, simplify the manufacturing process, and reduce costs by reducing the weight of the top plate itself.

  The present invention will be described more specifically with reference to examples.

Example 1
i) Production of Expandable Resin Composition (1) Preparation of Modified Polyolefin Resin BT40 (manufactured by Plastic Engineering Laboratories) Co-rotating twin screw extruder was used as a modification screw extruder. This is equipped with a self-wiping double thread, L / D is 35 and D is 39 mm. The cylinder barrel is composed of first to fourth barrels from the upstream side to the downstream side of the extruder, the die is a three-hole strand die, and a vacuum vent is installed in the fourth barrel to collect volatile components.

  The operating conditions are as follows.

・ Cylinder barrel set temperature: 1st barrel; 180 ℃
2nd barrel; 220 ° C
3rd barrel; 220 ° C
4th barrel; 220 ° C
Die: 220 ° C
・ Screw rotation speed: 150rpm

  First, a polyolefin resin and a dioxime compound were separately charged from the rear end hopper into the modification screw extruder having the above configuration, and both were melted and mixed to obtain a modified resin. At this time, the volatile matter generated in the extruder was evacuated by a vacuum vent.

The polyolefin resin was a polypropylene random copolymer (“EG8” manufactured by Mitsubishi Chemical Corporation, MI; 0.8 g / 10 min, density: 0.9 g / cm ³ ), and the supply amount was 10 kg / h.

  The modifying monomer was p-quinonedioxime (“Barunok GM-P” manufactured by Ouchi Shinsei Chemical Co., Ltd.), and the amount supplied was 0.75 parts by weight with respect to 100 parts by weight of the polyolefin resin.

  The modified resin obtained by melt-blending the polyolefin resin and the dioxime compound was discharged from a strand die, cooled with water, and cut with a pelletizer to obtain modified resin pellets.

(2) Preparation of foamable resin composition and preparation of composite sheet The screw extruder for kneading the foaming agent is a TEX-44 type (manufactured by Nippon Steel Co., Ltd.) co-rotating twin screw extruder, which is self-wiping 2 A strip screw is provided, and the L / D is 45.5 and D is 47 mm. The cylinder barrel is composed of first to twelfth barrels from the upstream side to the downstream side of the extruder, and the forming die is a T die having an outlet width of 500 mm and an outlet gap of 3.5 mm.

  The temperature setting categories are as follows.

The first barrel is always cooled
1st zone; 2-4 barrels
2nd zone; 5-8 barrels
3rd zone; 9th to 12th barrels
Zone 4; die and adapter section

  A side feeder is installed in the sixth barrel for supplying the foaming agent, and a vacuum vent is installed in the eleventh barrel for recovering volatile components.

  The operating conditions are as follows.

・ Cylinder barrel set temperature: 1st barrel; 150 ℃
Second barrel: 170 ° C
3rd barrel; 180 ° C
4th barrel; 160 ° C
-Screw rotation speed: 40rpm

  The modified resin obtained as described above was supplied from the reaction screw extruder to the blowing agent kneading screw extruder. The supply amount of the modified resin was 20 kg / h. Moreover, the foaming agent was supplied to the same extruder from the side feeder and dispersed. The blowing agent was azodicarbonamide (ADCA), and the supply amount was 1.2 kg / h.

When the foamable resin composition obtained by kneading the modified resin and the foaming agent is extruded from a T die and passed through three cooling rolls, an anchor effect is exerted on both the front and back surfaces of the foamable resin composition sheet. Non-woven fabric made of polyethylene terephthalate (Toyobo Co., Ltd., “Spunpond Ecule 6301A”, weighing 30 g / m ² , tensile strength: 1.6 kg / cm length, 1.2 kg / cm width) A polyolefin resin foamable composite sheet having a width of 460 mm and a thickness of 3.4 mm was obtained.

(3) Foaming The obtained polyolefin-based resin foam composite sheet was heated and foamed at 230 ° C. for about 8 minutes in a continuous foaming machine having a heating zone to obtain a composite foam.

The obtained composite foam (thickness 12 mm) is used as a core material, and an adhesive (“CH7WN” manufactured by Konishi Co., Ltd.) is applied to both sides of the core material using a roll coater, and then a decorative board is provided on the front surface and the back surface is lined. The materials were stacked and subjected to press treatment (press pressure 1 to 10 kgf / cm ² pressurization time: 2 hours) with a cold press.

  A melamine decorative board (thickness 1.2 mm) was used as the decorative board. Further, a phenol laminate (thickness 0.8 mm) was used as the backing material.

  Next, the laminated body is taken out from the press machine and cured for a predetermined time [summer (April to September): 2 hours, winter (October to March): 4 hours]. Created. The obtained decorative board laminated foam was cut into a predetermined shape to obtain a top board.

(Example 2)
A top plate was obtained in the same manner as in Example 1 except that the core material and the decorative plate and the MDF plate material having a thickness of 3.0 mm were laminated between the core material and the backing material.

(Comparative Example 1)
A paper honeycomb having a thickness of 21 mm is used as a core material, a melamine decorative board (thickness 0.8 mm) is used on the front surface, a phenol laminate is used on the back surface, and the thickness is between the core material and the decorative board and between the core material and the backing material. A sample was taken from the top table of the office table laminated and integrated through a 3.0 mm thick MDF plate.

(Comparative Example 2)
A paper honeycomb with a thickness of 15 mm is used as the core, a melamine decorative board (thickness 0.8 mm) is used on the front surface, and a phenol laminate is used on the back surface. Between the core material and the decorative board, and between the core material and the backing material A sample was taken from the top plate of the office table laminated and integrated with the MDF plate material having a thickness of 3.0 mm.

About the said Example and comparative example, based on JISK7221, the 3 point | piece bending test was done, while bending elastic modulus and bending strength were measured, the peeling condition of the adhesive interface was evaluated.
The evaluation results are shown in Table 1.

  As is clear from Table 1, it was found that the top plate of the present invention has a very high bending elastic modulus and bending strength, and there is no peeling of the adhesive interface.

Claims (4)

  A face material for suppressing the foaming force in the in-plane direction generated when the polyolefin resin foam sheet is heated and foamed on both surfaces of a polyolefin resin foam sheet in which individual cells are oriented in the thickness direction. A decorative foam laminated foam in which a decorative board is laminated and integrated on at least one surface of a core material laminated with the decorative board, wherein the decorative board is laminated and integrated with the face material by an anchor effect. A decorative foam laminated foam.   The decorative board laminated foam according to claim 1, wherein the decorative board is a melamine decorative board, and a phenol laminated board is used as a backing material.   3. A flash structure in which the core material is filled in a space surrounded by a frame material, and is laminated and integrated via a plywood between the decorative board and the core material. Decorative board laminated foam. A top board, wherein the decorative board laminate foam according to any one of claims 1 to 3 is used.