JP2006225931A - Flame-proofing panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flame-proofing panel excellent in light weight and capable of achieving both a satisfactory flame-proofing property and a satisfactory property to be pinned up. <P>SOLUTION: In a core material 3, face materials for suppressing a foaming force in in-plane directions, which occurs when foaming sheet raw fabric of a polyolefin-based resin foam is heated and foamed, are layered on both surfaces of a polyolefin-based resin foam in which individual bubbles are oriented in thickness directions. Metal sheets 21 and 22 (preferably aluminum sheets) and/or flame-proofing face materials 1 are layered on at least one surface of the core material 3. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a flameproof panel, and more particularly, to a lightweight flameproof panel having both pinup and flameproof properties.

  2. Description of the Related Art Conventionally, partition panels and display panels used in exhibitions and the like have been used in many cases with flammable wood and flammable panels such as styrene foam as core materials. In recent years, due to fire prevention problems, those obtained by subjecting the core material itself to incombustibility and flame retardancy, and those obtained by laminating the surface layer decorative face material that has been subjected to the same incombustibility and flame retardancy treatment to the core material are being used.

  However, when a wood-based panel is used as a core material, the weight is large, and it becomes easy to cause an obstacle in construction. In the case of a foamed resin material, the so-called pin-up property is hindered, and it may be difficult to fix the exhibit to the panel with pins.

  As means for solving the above-mentioned problems, for example, Patent Document 1 discloses that both sides of a core material such as a honeycomb material and a synthetic resin foam are flammable, such as fiberboard, plywood and wood, and have excellent pinup properties. The base material is bonded to each other, and the surface of each base material is bonded with calcium silicate paper with an adhesive mixed with a flame retardant. A flameproof panel characterized by adhering a decorative material with an adhesive mixed with a flame retardant is disclosed.

  However, in the above case, the construction is such that the weight increases because the wood panel is laminated in order to maintain pinup properties on the core material with a low specific gravity such as honeycomb material or synthetic resin foam. In addition to this problem, there is a concern about an increase in manufacturing costs.

  Moreover, even if the flameproofing function as a whole structure can be provided by laminating sheets that can be subjected to a flameproofing treatment or expected to have a flameproofing effect using the resin foam as a core material, generally it is 5 times or less. In the case of the expansion ratio, the surface layer is hard, and it becomes easy to cause trouble when the pin is inserted. On the other hand, if the resin foam has a foaming ratio of 5 times or more, the pin can be stabbed, but pin fixing is likely to be unstable, and pin-up properties that are effective for fixing displays such as display panels. Tends to be inhibited.

JP-A-8-199705

  An object of the present invention is to solve the above problems and provide a flameproof panel that can exhibit good pinup properties and flameproofness while using a polyolefin-based rigid foam excellent in lightness.

  The flameproof panel according to claim 1 is a surface generated when the foamable sheet raw material of the polyolefin resin foam is heated and foamed on both surfaces of the polyolefin resin foam in which individual bubbles are oriented in the thickness direction. A metal sheet and / or a face material that has been subjected to a flameproof treatment are laminated on at least one surface of a core material that is laminated with a face material for suppressing the foaming force in the inward direction.

  The flameproof panel according to claim 2 is the flameproof panel according to claim 1, wherein the metal sheet is an aluminum sheet.

  Hereinafter, the present invention will be described in detail.

  The core material in the present invention is an in-plane direction generated when the foamable raw sheet of the polyolefin resin foam is heated and foamed on both surfaces of the polyolefin resin foam, in which individual bubbles are oriented in the thickness direction. The face material for suppressing the foaming force is laminated.

  The method for producing the core material is not particularly limited. For example, the core material is selected from polyolefin resins and dioxime compounds, bismaleimide, divinylbenzene, allyl polyfunctional monomers, (meth) acrylic polyfunctional monomers, and quinone compounds. 2 to 20 parts by weight of a thermal decomposable 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 type of modifying monomer. After forming the foamable sheet raw fabric by molding, the surface material is fused to both sides of the obtained foamable sheet raw fabric, and the raw fabric is heated to a temperature equal to or higher than the decomposition temperature of the thermal decomposition type chemical foaming agent. There is a method of foaming only in the thickness direction while suppressing foaming force generated in the in-plane direction by the 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 both surfaces of the original foam sheet is not particularly limited. For example, (a) a method of applying the face material to the foam sheet once cooled and solidified while heating, (b) Examples thereof include a method of heating the foamable sheet until it is in a molten state and thermally fusing it to the face material, and (c) a method of attaching the face material 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).

The basis weight of the face material is preferably 10 to 300 g / mm ² . If the weight per unit area is less than 10 g / mm ² , pinup properties may be difficult to obtain. If it exceeds 300 g / mm ² , the flexibility of the face material is impaired, and this is continuously pasted to the core material. In addition, since it becomes difficult to heat the foamable sheet through the face material, the face material and the foamable sheet are not fused uniformly, and the cell structure becomes non-uniform due to peeling or the like.

  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.

  Although it does not specifically limit as an expansion ratio of the said foam, It is preferable that it is 5 to 30 times from the point of the balance of lightweight property and pinup property.

  In this invention, it becomes what was excellent in pinup property by using the said core material. Here, the pinup property refers to a function of inserting and fixing a pin in a panel. Generally, the pinup property tends to be inferior in the foamed polystyrene or urethane-based high-magnification foam. Insulation boards, corks, balsa materials, and other materials that contain fibers usually have good pinup properties. This is due to the fact that the fiber layer is entangled with the pin that is pointed to cause a fixed holding function. Conceivable. Resin plates and inorganic boards are too hard to puncture normally.

  In the present invention, the above-mentioned air bubbles are oriented in the thickness direction, and the in-plane direction generated when the foamable sheet raw fabric of the polyolefin resin foam is heated and foamed on both surfaces of the polyolefin resin foam. By using a core material in which a face material for suppressing the foaming force of the material is laminated, the effect of improving pin fixing and holding performance by the face material laminated on the surface, and the face material of the polyolefin resin foam It is presumed that the effect of improving the pin fixing and retaining property is exhibited by forming a skin layer having a high density in a portion in contact with the pin.

  Therefore, even if the foaming ratio of the polyolefin resin foam is increased, good pinup properties can be obtained, so that the specific gravity of the core material can be 1/3 or less of the plywood.

  The flameproof panel of the present invention is formed by laminating a metal sheet and / or a flameproofed surface material on at least one surface of the core material.

Although it does not specifically limit as said metal sheet, An aluminum sheet is preferable at the point which is excellent in the balance of lightweight and flameproofness.
When the aluminum sheet is used alone, the thickness is preferably 5 to 80 μm.
This is because when the thickness is less than 5 μm, the flameproofness is insufficient, and when it exceeds 50 μm, the pin-up property and the lightness are impaired.

The face material subjected to the above flameproofing treatment is not particularly limited, and examples thereof include non-combustible paper containing an inorganic substance such as aluminum hydroxide and glass fiber. Among them, aluminum hydroxide and glass fiber are particularly preferable. Non-combustible paper containing an inorganic substance is preferred. This is because when the flame reaches the non-combustible paper and the combustion start temperature is reached, the compounded aluminum hydroxide reacts with oxygen to start an endothermic reaction. At this time, water is precipitated by the oxidation reaction and self-digestion occurs. . Therefore, the effect of suppressing the spread of the non-combustible paper itself is generated, and by suppressing the spread of the surface layer, it is expected to suppress the increase in the ambient temperature and minimize the spread of the core material due to moisture generated from the non-combustible paper. Because it is done.
Weight per unit area of the surface material is preferably 30 g / ^{m 2} or more, more preferably from 50 to 300 g / ^{m 2.} This is because if the weight per unit area is too small, the flameproofness becomes insufficient, and if it is too large, it is difficult to laminate the core material.

  In the above, when a metal sheet is interposed between the face material and the core material subjected to flameproofness, in addition to stopping the direct flame to the core material surface from contacting the core material, The effect of blocking the supply of oxygen that generates combustion is expected, and in this case, it is preferable in that the flameproofing effect is further improved.

  The laminated structure of the metal sheet and / or the face material subjected to the flameproofing treatment is not particularly limited, and may be a single layer or multiple layers, and each layer is alternately laminated. May be.

  The flameproof panel of the present invention has an in-plane generated when the foamed sheet raw fabric of the polyolefin resin foam is heated and foamed on both surfaces of the polyolefin resin foam in which individual bubbles are oriented in the thickness direction. Lightweight because it is characterized in that a metal sheet and / or a flameproofed surface material is laminated on at least one side of a core material in which a surface material for suppressing the foaming force in the direction is laminated In addition, it is possible to provide a flameproof panel having both pinup and flameproof properties.

  In the case where the metal sheet is an aluminum sheet, the balance between lightness and flameproofness is improved, and the above effect is further ensured.

  The present invention will be described more specifically with reference to examples. In addition, this invention is not limited only to the following Example.

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 thus obtained by kneading the modified resin and the foaming agent is extruded from a T-die and passed through three cooling rolls, it is used as a face material on both the front and back surfaces of the foamable resin composition sheet. , A non-woven fabric made of polyethylene terephthalate (manufactured by Toyobo Co., Ltd., “Spunpond Ecule 6301A”, basis weight 30 g / m ² , tensile strength: length 1.6 kg / cm, width 1.2 kg / cm), 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 using a continuous foaming machine having a heating zone to obtain a composite foam having a thickness of 7 mm. In the polyolefin resin foam constituting the obtained composite foam, the bubbles were oriented in the thickness direction, and the expansion ratio was 10 times.

The obtained composite foam is used as a core material, and as shown in FIG. 1, a face material (hereinafter also referred to as “non-combustible paper”) 1 subjected to a flameproof treatment, an aluminum sheet 21 (thickness 7 μm), and a core material 3 A flameproof panel 5 was prepared in which an aluminum sheet 22 (thickness 7 μm) and plain paper 4 (weight per unit area 60 g / m ² ) were laminated in this order. As the non-combustible paper 1, non-combustible paper (“Cerafoam W-135AF”, weight per unit area 135 g / m ² , manufactured by Lintec Co., Ltd.) containing inorganic substances such as aluminum hydroxide and glass fiber was used.

  As a laminating method, a non-flammable paper 1 and an aluminum sheet 21 are heat-laminated through a polyethylene film, a urethane coat type hot melt adhesive is applied using a roll coater, and then the upper surface of the core material 3 is applied. After laminating by heating and pressurizing, and applying a urethane-based reactive hot melt adhesive using a roll coater to a laminate of plain paper 4 and aluminum sheet 22 via a polyethylene film, a core material The lower surface of 3 was laminated by heating and pressing.

(Example 2)
Example 1 is the same as Example 1 except that non-combustible paper (Made by Lintec, “Cerafoam HC-180A”, weight per unit area 180 g / m ² ) containing inorganic substances such as aluminum hydroxide and glass fiber is used as non-combustible paper 1. A flameproof panel was made.

(Example 3)
Except that non-combustible paper 1 (non-combustible paper made by Miyoshi Paper Co., Ltd., “Sunwall”, weight per unit area 120 g / m ² ) was used as non-combustible paper 1 in the same manner as in Example 1. A fireproof panel was created.

Example 4
A flameproof panel was prepared in the same manner as in Example 1 except that the aluminum sheet was not used.

(Comparative Example 1)
A flameproof panel in which non-combustible paper 1 (manufactured by Lintec Corporation, “Cerafoam W-135AF”, basis weight 135 g / m ² ) was laminated on both surfaces of the core material 3 was prepared.

(Comparative Example 2)
A flameproof panel in which non-combustible paper (manufactured by Lintec, “Cerafoam W-135AF”, weight per unit area 135 g / m ² ) was laminated on both sides of polystyrene foam (thickness 7 mm, expansion ratio 30 times) was prepared.

(Comparative Example 3)
A flameproof panel was prepared in the same manner as in Example 2 except that foamed polystyrene (thickness 7 mm, foaming ratio 30 times) was used as the core material 3.

  About the said Example and comparative example, flameproof performance and pinup property were evaluated. The flameproof performance was evaluated by the 45 ° Meckel burner method (based on the flameproof test for display panels in the Flameproof Association). The evaluation results are shown in Table 1.

  As is clear from Table 1, the flameproof panel of the present invention was found to be lightweight and excellent in pinup properties while having high flameproof performance.

It is a schematic cross section which shows an example of the flameproof panel of this invention.

Explanation of symbols

1 Face material (incombustible paper) that has been subjected to flameproofing
21, 22 Metal sheet (aluminum sheet)
3 Core material 4 Plain paper 5 Flameproof panel

Claims (2)

  In order to suppress the foaming force in the in-plane direction generated when the foamed sheet raw fabric of the polyolefin resin foam is heated and foamed on both surfaces of the polyolefin resin foam in which individual bubbles are oriented in the thickness direction A flameproof panel comprising a metal sheet and / or a flameproofed face material laminated on at least one surface of a core material obtained by laminating face materials. The flameproof panel according to claim 1, wherein the metal sheet is an aluminum sheet.

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