JP2013103467A - Polystyrene resin extrusion foaming laminate having superior thermal insulation performance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polystyrene resin extrusion foaming laminate for heat insulating material that has the improvement effect of a remarkable thermal insulation performance.SOLUTION: The foam laminate that has the improvement effect of the thermal insulation performance can be obtained by assuming the foam laminate that has at least one structure from which the foam layer is accumulated to the thickness direction through the non-foamed layer. A remarkable thermal insulating performance can be imparted by containing the heat ray radiation inhibitor of the white color in the foam layer and the heat ray radiation inhibitor of the black color in the non-foamed layer lying between the foam layers, and the identification and processing control of the state of the laminate of the non-foamed layer of the thin film becomes easy by different colors of the heat ray radiation inhibitor. In addition, temperature-rise of the foam laminate by sunlight etc. can be controlled by distributing the foam layer that contains the heat ray radiation inhibitor of the white color in the thickness direction outermost layer of the foam laminated structure, and the deformation of the member can be prevented. Since the colors of the radiation inhibitors are different, the identification and the processing control in the state of the laminate of the non-foamed layer of the thin film become easy.

Description

  The present invention relates to an extruded foam laminate suitably used as a heat insulating material for buildings, automobiles, civil engineering and the like.

  In the field of building materials, automotive interior materials, etc., phenolic resin foam boards, polyurethane resin foam boards, and polystyrene resin foam boards are widely used as heat insulating materials.

  In recent years, as the demand for comfort and energy saving in living spaces has increased, there has been a demand for improvement in the heat insulation performance of heat insulation materials that have been used in the past. Various studies have been made, such as a study of resins constituting the resin, a study of foaming agent types, a study of additives, and a study of cell structure (see Patent Documents 1 to 6).

  As a result of these studies, the thermal insulation performance of the foam board has been dramatically improved. On the extension line of the prior art, there is a view that a further improvement of the thermal insulation performance cannot be easily expected.

  On the other hand, chlorofluorocarbons, which are one type of foaming agent that gives good insulation performance to foamed boards, are considered to be the causative substances that destroy the ozone layer. It ’s been a long time since the abolition was screamed.

  Under such circumstances, in order to further improve the heat insulation performance of the foam board, an approach different from the viewpoint of the above-described investigation that has been conventionally performed is necessary.

  As a new attempt for improving the heat insulation performance of the foam board, there is a technique disclosed in Patent Document 7. This is made by laminating and integrating two or more types of polystyrene resin foam layers having different average cell diameters, including carbon black or graphite as a radiation inhibitor, and the upper and lower surface layers in the thickness direction of the laminated foam contain a radiation inhibitor. By comprising a foam layer that does not, it has good heat resistance and dimensional stability that can improve the thermal conductivity by adding a radiation inhibitor and suppress the temperature rise due to solar radiation.

  As a new attempt for further improving the heat insulation performance of the foam board, there is a technique disclosed in Patent Document 8. This is an invention in which an aluminum foil is sandwiched between two polypropylene resin foams, and the thermal insulation performance is remarkably improved by sandwiching the aluminum foil. However, the technique disclosed in Patent Document 8 is limited to a polypropylene resin foam having low heat insulation performance.

  This technology has been applied to polystyrene resin foam boards, polyurethane resin foam boards, and polyphenol resin foam boards with high heat insulation performance, and there is a technique disclosed in Patent Document 9, where the foam layer suppresses heat radiation in the thickness direction. By making a foamed laminate having at least one structure laminated via a non-foamed layer containing an agent, it is considered to have a remarkable effect of improving heat insulation performance.

  However, only the addition of the heat ray radiation inhibitor to the non-foamed layer which is a thin film has a small effect of improving the heat insulation performance, and the appearance of a material having higher heat insulation performance is desired.

JP 2008-13659 A JP 2007-154006 A JP 2001-114922 A JP 2002-309030 A JP-A-8-231667 JP 2007-332203 A Japanese Patent No. 3916460 JP 2001-179866 A JP 2009-234261 A

  This invention solves the said subject, and it aims at providing the extrusion foaming laminated body for heat insulating materials which has the improvement effect of a remarkable heat insulation performance, without using Freon as a foaming agent.

As a result of intensive studies to solve the above-mentioned problems, the present inventor found the following matters and completed the present invention.
● The thermal insulation performance of a foamed laminate having a plurality of foamed layer / non-foamed layer / foamed layer structures in the thickness direction of the polystyrene-based resin foamed laminate is improved as compared with a foamed laminate having only one structure.
● By blending titanium oxide, which is a white heat ray radiation inhibitor, as a heat ray radiation inhibitor in the foam layer constituting the polystyrene resin foam laminate, the heat insulation performance is improved by scattering and attenuating the heat rays. Furthermore, by arranging the foam layer on the outermost layer surface layer of the foam laminate, a heat ray absorbent such as carbon black, a heat ray reflective agent such as carbon graphite, etc. was blended in the outermost layer. An increase in the surface temperature of the foam laminate due to direct sunlight is suppressed with respect to the laminate, warpage can be suppressed, and dimensional stability can be ensured.
● High heat insulation performance by absorbing and attenuating heat rays by blending carbon graphite with carbon black as a heat ray radiation inhibitor in the resin constituting the non-foamed layer and by absorbing and attenuating the heat rays. Is expressed. The non-foamed layer containing carbon black and carbon graphite as a heat ray radiation inhibitor is interposed between the foam layers and is not exposed on the surface in the thickness direction of the laminate, so it can also be used for blending black heat ray radiation inhibitors. Regardless, temperature rise of the foamed laminate due to direct sunlight does not occur, dimensional stability can be secured, and suitable heat insulation performance can be obtained.
● By changing the color of the white heat ray radiation inhibitor mixed in the foam layer and the black heat ray radiation inhibitor compounded in the non-foam layer, the laminated state of the thin non-foam layer in the thickness direction cross section Can be easily visually identified, improving processing accuracy and facilitating processing management.
● By blending a heat ray radiation inhibitor into the resin constituting the foamed layer and non-foamed layer by an industrially advantageous coextrusion method, the effect of suppressing heat ray radiation can be easily obtained. / A foam laminate having a higher heat insulation performance having a structure composed of a foam layer is obtained.

That is, the present invention
[1] A foam laminate having at least one structure in which a foam layer is laminated via a non-foam layer in the thickness direction,
The foamed layer contains a white heat ray radiation inhibitor, the non-foamed layer contains a black heat ray radiation inhibitor, the foam layer is disposed in the outermost layer in the thickness direction, and the density of the laminated structure is 45 kg / m ³ or less, and having a thermal conductivity at 20 ° C. of 1 week after production of 0.028 W / m · K or less, a polystyrene resin extruded foam laminate,
[2] The polystyrene according to [1], wherein the white heat ray radiation inhibitor is titanium oxide and / or alumina oxide, and the black heat ray radiation inhibitor is carbon black and / or graphite. The polystyrene resin extruded foam laminate according to [1] or [2], wherein the extruded resin foam laminate and [3] the extruded laminate foam are produced by a coextrusion method .

The effects of the present invention are as follows.
A foam laminate having at least one structure in which a foam layer is laminated via a non-foam layer in the thickness direction, and a white heat ray radiation inhibitor such as titanium oxide or alumina is added to the foam layer. The heat insulation performance is greatly improved by the foamed laminate structure containing the black heat ray radiation inhibitor such as carbon black and carbon graphite in the foamed layer.
● The heat insulation performance is further improved by repeating the structure comprising a foam layer / non-foam layer / foam layer containing a heat ray radiation suppressor at least once.
● By disposing a foam layer containing a white heat ray radiation suppressor such as titanium oxide or alumina in the outermost layer in the thickness direction of the component, heat storage due to direct sunlight can be prevented, and dimensional stability such as deformation suppression can be maintained.
● By changing the color of the heat ray radiation inhibitor to be blended between the foamed layer and the non-foamed layer, the lamination state of the thin non-foamed layer in the cross section in the thickness direction can be easily identified visually, improving processing accuracy and processing Management can be facilitated.
Since the above effect can be combined with the prior art for improving the heat insulating property of the foam board, it can be expected to provide a foam board having an excellent heat insulation performance that has not been obtained conventionally.

FIG. 1 is a schematic view of a cross section in the thickness direction of a polystyrene resin extruded foam laminate showing an example of the present invention.

  The extruded foam laminate of the present invention has at least one structure in which a foam layer is laminated via a non-foam layer in the thickness direction, and a white heat ray radiation inhibitor is contained in the foam layer. It is necessary to contain a black heat ray radiation inhibitor in the inside. Furthermore, it is necessary that a foam layer containing a white-based thermal warpage radiation inhibitor is disposed on the outermost layer in the thickness direction.

  The foam layer constituting the extruded foam laminate of the present invention refers to one having a plurality of honeycomb-like cell structures, and includes a white heat ray radiation inhibitor as a constituent material. The shape is not particularly limited, and examples thereof include a film shape, a sheet shape, and a board shape. Among these, a sheet shape and a board shape are easy to express heat insulation performance and can give lightweight to the foamed laminate. Is preferred.

The non-foamed layer constituting the extruded foam laminate of the present invention refers to a layer having a density exceeding 500 kg / m ³ and contains a black heat ray radiation inhibitor as a constituent material. The shape of the non-foamed layer is preferably a film shape or a sheet shape because it can impart lightness to the foamed laminate. The configuration of the non-foamed layer is not particularly limited, and may be a single layer or multiple layers. For example, the non-foamed layer may be composed of a single heat ray radiation inhibitor, a heat ray radiation inhibitor, a heat ray radiation inhibitor, and a heat ray radiation. Examples include a composite of materials that do not have an inhibitory effect.

The heat ray radiation inhibitor contained in the foamed layer constituting the extruded foam laminate of the present invention reflects, scatters and absorbs light in the near infrared or infrared region (for example, a wavelength region of about 800 to 3000 nm). A material having characteristics.
Examples of the heat ray radiation suppressor include a heat ray reflective agent and a heat ray absorbent.

  Specific examples of the white heat ray radiation inhibitor contained in the foamed layer of the present invention include lead white, zinc oxide, titanium oxide, zinc sulfide, lithopone (mixture of zinc sulfide and barium sulfide), antimony white. , Mica, aluminum oxide, alumina white, white carbon, hydrotalcite, shirasu balloon, ceramic balloon, microballoon, pearl mica and the like. These may be used alone or in combination of two or more.

  The white heat ray radiation inhibitor contained in the foamed layer of the present invention has a large thermal conductivity reducing effect, the foam laminate can be stored outdoors, and the temperature rise due to direct sunlight can be suppressed during construction, cost In particular, titanium oxide and alumina oxide are preferable because of their favorable advantages, good handling properties including environmental compatibility and safety.

The average particle diameter of the white heat ray radiation inhibitor contained in the foamed layer of the present invention is not particularly limited, but a small particle diameter is preferable from the viewpoint of dispersibility in the resin and color developability. 0.1 to 0.5 μm is preferable, and 0.15 to 0.3 μm is more preferable. When the average particle size of the white heat ray radiation inhibitor is in the range of 0.1 to 0.5 μm, the dispersibility and color developability are good, and the degree of color development in the visible light region of 400 to 800 nm can be improved.
On the other hand, when it is desired to suppress infrared absorption into the resin in the near infrared to far infrared region, the average particle size of the white heat ray radiation inhibitor is preferably a large particle size, that is, 0.8 to 1.5 μm. Preferably, 0.8 to 1.0 μm is more preferable.

  By mixing the white heat ray radiation inhibitor having different average particle diameters with the white heat ray radiation inhibitor having a small particle diameter within the range of 10 to 90% by weight, the reflection in the infrared region and the visible light region can be achieved. A mixed titanium oxide with improved whiteness can be obtained.

The amount of white heat ray radiation inhibitor contained in the foam layer of the present invention is appropriately set depending on the type of heat ray radiation inhibitor, the thickness of the foam layer containing the heat ray radiation inhibitor,
As the index, setting the addition amount so that there is almost no change in absorbance at 800 to 3000 nm of the spectrum measured with an infrared spectrophotometer (IR) is effective in reducing the thermal conductivity of the foam laminate and the cost. Is preferable, preferably 0.1 to 10 parts by weight, more preferably 1 to 8 parts by weight, and still more preferably 2 to 4 parts by weight with respect to 100 parts by weight of the styrenic resin.

The heat ray radiation inhibitor contained in the non-foamed layer constituting the extruded foamed laminate of the present invention is the same as that contained in the foamed layer, as in the near infrared or infrared region (for example, a wavelength of about 800 to 3000 nm). It is a material that has the property of reflecting, scattering, and absorbing the light in the region.
Examples of the heat ray radiation suppressor include a heat ray reflective agent and a heat ray absorbent.

  Specific examples of the black heat ray radiation inhibitor contained in the non-foamed layer of the present invention include graphite, carbon black, chromium black, and copper chromate. These may be used alone or in combination of two or more.

Among these, carbon black and graphite are preferable because they have a large effect of reducing thermal conductivity, are advantageous in cost, and have good handling properties including environmental compatibility and safety.
The graphite may be natural graphite such as flake graphite, block graphite, earth graphite, artificial graphite, or pyrolytic graphite. The graphite preferably has a fixed carbon number of 80% or more, and more preferably 90% or more.

  The average particle size of the black heat ray radiation inhibitor contained in the non-foamed layer of the present invention is not particularly limited, but for example, the average particle size of carbon black is 0.01 to 0.3 μm. Is preferable, and 0.2 to 0.25 μm is more preferable. Further, the average particle diameter of graphite is preferably 1 to 30 μm, and like titanium oxide, it affects the color developability and the degree of far-infrared absorption / reflection in the infrared region, and is more preferably 5 to 15 μm.

The addition amount of the black heat ray radiation inhibitor contained in the non-foamed layer of the present invention is appropriately set depending on the type of heat ray radiation inhibitor, the thickness of the non-foamed layer containing the heat ray radiation inhibitor,
As the index, setting the addition amount so that there is almost no change in absorbance at 800 to 3000 nm of the spectrum measured by an infrared spectrophotometer (IR) is effective in reducing the thermal conductivity of the foam laminate and the cost. The balance is good and preferably 0.1 to 20 parts by weight, more preferably 0.3 to 10 parts by weight, and still more preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the styrene resin.

  By making the heat ray radiation inhibitor contained in the foamed layer of the present invention white, and by making the heat ray radiation inhibitor contained in the non-foamed layer black, the state of lamination between both layers is visually observed. It can be easily identified, and it is possible to improve the management accuracy of the laminating process and thereby improve the processing accuracy.

  It is preferable to repeat the structure composed of a foamed layer / non-foamed layer / foamed layer containing a heat ray radiation suppressor at least once. The reason for this is that by taking a structure in which the foam layer is laminated on both sides of the non-foam layer, absorption attenuation by the heat radiation inhibitor contained in the non-foam layer and scattering by the heat radiation inhibitor contained in the foam layer are considered. This is because the thermal conductivity reduction effect due to both attenuations due to attenuation can work more effectively. In addition, the presence of a plurality of non-foamed layers such as foamed layer / non-foamed layer / foamed layer / non-foamed layer / foamed layer has an excellent thermal conductivity reduction effect that cannot be obtained with a single non-foamed layer. To express.

In the extruded foam laminate of the present invention, it is preferable to dispose a foam layer containing a white heat ray radiation inhibitor such as titanium oxide or alumina oxide in the outermost layer in the thickness direction of the structure.
When the foam layer is configured to include a black heat ray radiation suppressor in the outermost layer in the thickness direction of the foam laminate, the surface temperature of the foam laminate due to solar radiation may remarkably increase and deformation may occur.
Similarly, when a non-foamed layer containing a black heat ray radiation suppressor is disposed in the outermost layer in the thickness direction of the constituent body, similarly, there is a risk of deformation due to a rise in the temperature of the foamed laminate surface due to solar radiation.
For these reasons, by disposing a foam layer containing a white heat ray radiation suppressor in the outermost layer in the thickness direction of the constituent body, an increase in the surface temperature of the foam laminate due to solar radiation can be suppressed, and dimensional stability can be maintained.

  Furthermore, by changing the color of the white heat ray radiation inhibitor blended in the foam layer and the black heat ray radiation inhibitor blended in the non-foam layer, the thin non-foam layer is laminated in the thickness direction cross section. The state can be easily identified visually, improving machining accuracy and facilitating machining management.

  As the constituent resin of the foamed layer constituting the extruded foam laminate of the present invention, styrene-based resins such as polystyrene; polyphenylene ether-based resins, modified polyphenylene ether-based resins and the like are excellent in heat insulation performance and easy moldability. Can be mentioned. Among these, styrenic resins are preferable from the viewpoint of processability and economy.

  The styrenic resin is not particularly limited, and for example, a styrene homopolymer obtained only from a styrene monomer, a random, block or graft obtained from a monomer copolymerizable with a styrene monomer and styrene or a derivative thereof. Examples thereof include copolymers, post-brominated polystyrene, modified polystyrene such as rubber-reinforced polystyrene, and ABS resin. These can be used individually or in mixture of 2 or more types.

  Examples of monomers copolymerizable with styrene include methylstyrene, dimethylstyrene, ethylstyrene, diethylstyrene, isopropylstyrene, bromostyrene, dibromostyrene, tribromostyrene, chlorostyrene, dichlorostyrene, and trichlorostyrene. Polyfunctional vinyl compounds such as divinylbenzene, (meth) acrylic compounds such as acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, methacrylonitrile, α-chloroacrylonitrile, acrylonitrile Diene compounds such as budadiene or derivatives thereof, unsaturated carboxylic acid anhydrides such as maleic anhydride, itaconic anhydride, citraconic anhydride, N-methylmaleimide, N-butylmaleimide N-alkyl-substituted maleimide compounds such as N-cyclohexylmaleimide, N-phenylmaleimide, N-4-diphenylmaleimide, N-2-chlorophenylmaleimide, N-4-bromophenylmaleimide, N-1-naphthylmaleimide; It is done. These can be used individually or in mixture of 2 or more types.

  It does not specifically limit as a foaming agent used when obtaining the foaming layer which comprises the extrusion foaming laminated body of this invention, For example, propane, n-butane, i-butane, n-pentane, i-pentane, neopentane, etc. A saturated hydrocarbon having 3 to 5 carbon atoms; ethers such as dimethyl ether, diethyl ether, methyl ethyl ether, isopropyl ether, n-butyl ether, diisopropyl ether, furan, furfural, 2-methyl furan, tetrahydrofuran, tetrahydropyran; acetone, Ketones such as methyl ethyl ketone, diethyl ketone, methyl n-propyl ketone, methyl n-butyl ketone, methyl i-butyl ketone, methyl n-amyl ketone, methyl n-hexyl ketone, ethyl n-propyl ketone, ethyl n-butyl ketone; Alcohol, ethanol, propyl alcohol, i-propyl alcohol, butyl alcohol, i-butyl alcohol, t-butyl alcohol; methyl formate, ethyl formate, propyl formate, butyl formate, amyl formate, methyl acetate, ethyl acetate, Esters such as propyl acetate, butyl acetate, amyl acetate, methyl propionate and ethyl propionate; alkyl halides such as methyl chloride and ethyl chloride; inorganic foaming agents such as water and carbon dioxide; azo compounds and tetrazoles Chemical foaming agents such as These foaming agents may be used independently and may use 2 or more types together.

  Among these foaming agents, n-butane, i-butane, propane, dimethyl ether, diethyl ether, methyl ethyl ether, methyl chloride, ethyl chloride, and the like are preferable from the viewpoint of foamability and foam moldability. Water and carbon dioxide are preferable from the viewpoints of flammability, flame retardancy or heat insulation of the foam, and more preferably n-butane, i-butane, propane, dimethyl ether, water, Carbon dioxide.

When the foamed layer made of the thermoplastic resin constituting the extruded foam laminate of the present invention is produced, the amount of the foaming agent added or injected into the thermoplastic resin is appropriately determined according to the setting value of the foaming ratio, etc. In general, the total amount of the foaming agent is preferably 1 to 20 parts by weight and more preferably 3 to 8 parts by weight with respect to 100 parts by weight of the thermoplastic resin.
When the total addition amount of the foaming agent is 1 to 20 parts by weight, there is no void in the foam, and a foam layer with an appropriate foaming ratio that can control flame retardancy is obtained. The characteristics are expressed.

  The pressure at the time of adding or injecting the foaming agent is not particularly limited as long as it is higher than the internal pressure of an extruder or the like.

  The average cell diameter in the foamed layer made of the thermoplastic resin constituting the extruded foam laminate of the present invention is preferably 0.05 to 1 mm, more preferably 0.06 to 0.5 mm, and 0.08 to 0.3 mm. Particularly preferred. When the average cell diameter in the foamed layer is in the range of 0.05 to 1 mm, the heat ray shielding effect can be effectively expressed, and a foamed layer having heat insulation can be obtained.

The density of the foamed layer made of the thermoplastic resin constituting the extruded foam laminate of the present invention is preferably 40 kg / m ³ or less, and in order to give lighter weight and excellent heat insulation, 20 to 35 kg / m ^3. Is more preferable, and it is further more preferable that it is 25-30 kg / m < ³ >. When the density of the foam layer is in the range of 20 to 40 kg / m ³ , a foam layer having light weight and heat insulation can be obtained.

  In the production of the foamed layer constituting the extruded foam laminate of the present invention, if necessary, flame retardant, flame retardant aid, silica, talc, calcium silicate, wollastonite, kaolin, clay, mica, zinc oxide , Inorganic compounds such as titanium oxide and calcium carbonate; processing aids such as sodium stearate, magnesium stearate, barium stearate, liquid paraffin, olefin wax, stearyl amide compound; phenolic antioxidant, phosphorus stabilizer It is preferable to add additives such as nitrogen-based stabilizers, sulfur-based stabilizers, light-resistant stabilizers such as benzotriazoles and hindered amines; antistatic agents; and colorants such as pigments.

  For more stable extrusion foaming, triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis {3 -(3,5-di-t-butyl-4-hydroxyphenyl) propionate}, 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino)- 1,3,5-triazine, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-t-butyl-4- Hydroxyphenyl) propionate, 3,5-di-t-butyl-4-hydroxy-benzyl phosphate-diethyl ester, 1,3,5-trimethyl-2,4,6- Hindered phenolic antioxidants such as ris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate; Phenylphosphite, tris (2,4-di-t-butylphenyl) phosphite, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, bisstearyl pentaerythritol diphosphite, bis (2 , 4-Di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, tetrakis (2,4-di-t-butylphenyl) [1,1-biphenyl] -4,4′-diylbisphosphonite Phosphorus stabilizers such as 2,2,4-trimethyl-1,2-dihydroquinoline polymer, alkylated diph Amine stabilizers such as nilamine, octylated diphenylamine, 4,4′-bis (α, α-dimethylbenzyl) diphenylamine, 3,3-thiobispropionic acid didecyl ester, 3,3′-thiobispropionic acid diester It is preferable to add a sulfur-based stabilizer such as octadecyl ester.

The foam layer made of the thermoplastic resin constituting the foam laminate of the present invention is preferably produced by extrusion foam molding by a coextrusion method.
As a molding method of extrusion foam molding, for example,
(I) The thermoplastic resin is mixed with the additive as necessary, and then melted by heating.
(Ii) One or more selected from the above-mentioned additives as necessary are mixed into the thermoplastic resin, and then heated and melted, and the remaining additive is added to the thermoplastic resin as it is, or liquefied or melted as necessary. Then heat and mix,
(Iii) A thermoplastic resin is mixed with one or more additives selected from the additives as necessary, and then a heat-melted composition is prepared, and then the composition and the remaining additive are added. If necessary, mix the thermoplastic resin again, supply to the extruder and melt by heating.
The thermoplastic resin, and if necessary, the additive is supplied to the heat-melting extruder, and then the foaming agent is added to the thermoplastic resin under high-pressure conditions at any stage, resulting in a fluid gel and extrusion foaming. By cooling to an appropriate temperature, supplying the fluidized gel to a multi-layer laminating apparatus such as a feed block, joining with a molten resin not containing a foaming agent, and then extrusion-foaming into a low-pressure region through a die to form a foamed layer. Can be manufactured.

In the present invention, the heating temperature, the melt-kneading time, and the melt-kneading means when heating and kneading the thermoplastic resin and additives such as a foaming agent are not particularly limited.
Although the heating temperature should just be more than the temperature which the thermoplastic resin to be used melt | dissolves, the temperature which suppresses the molecular degradation of resin by the influence of a flame retardant etc. as much as possible, for example, about 150-280 degreeC is preferable.
The melt-kneading time varies depending on the extrusion amount per unit time, the melt-kneading means, and the like, and thus cannot be determined unconditionally. However, the time required for uniformly dispersing and mixing the thermoplastic resin and the foaming agent is appropriately selected.
Examples of the melt-kneading means include a screw type extruder, but there is no particular limitation as long as it is used for ordinary extrusion foaming. However, in order to suppress the molecular deterioration of the resin as much as possible, it is preferable to use a low shear type screw shape for the screw shape.

  In the present invention, the foam molding method is not particularly limited, but for example, using a molding die and a molding roll in which a foam obtained by releasing pressure from a slit die is placed in close contact with or in contact with the slit die, A general method for molding a plate-like foam having a large size can be used.

  The thickness of the foam layer constituting the extruded foam laminate of the present invention depends on the thickness of the foam laminate and the number of non-foam layers in the foam laminate (number of units comprising foam layer / non-foam layer / foam layer). Are appropriately selected.

  As a resin constituting the non-foamed layer constituting the extruded foam laminate of the present invention (hereinafter sometimes referred to as “non-foamed layer constituting resin”), in order to ensure good adhesion with the foamed layer, foaming is performed. It is preferable to select a thermoplastic resin having compatibility with the layer constituent resin. In addition, even if it does not have compatibility with foamed-layer-constituting resin, it is possible to select a resin having adhesiveness and adhesiveness that exhibits an anchor effect with the foamed layer.

  Examples of the thermoplastic resin having compatibility with the resin constituting the foam layer include styrene resins such as polystyrene; polyphenylene ether resins and modified polyphenylene ether resins. Among these, styrenic resins are preferable from the viewpoint of processability and economy.

  The styrenic resin used as the non-foamed layer-constituting resin of the present invention is not particularly limited. For example, a styrene homopolymer obtained only from a styrene monomer, a monomer copolymerizable with styrene monomer and styrene Alternatively, random, block or graft copolymers obtained from derivatives thereof, modified polystyrene such as brominated polystyrene and rubber-reinforced polystyrene, ABS resin and the like can be mentioned. These may be used alone or in combination of two or more.

  As monomers copolymerizable with styrene, styrene derivatives such as methylstyrene, dimethylstyrene, ethylstyrene, diethylstyrene, isopropylstyrene, bromostyrene, dibromostyrene, tribromostyrene, chlorostyrene, dichlorostyrene, trichlorostyrene, Polyfunctional vinyl compounds such as divinylbenzene, (meth) acrylic compounds such as acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, methacrylonitrile, α-chloroacrylonitrile, acrylonitrile , Diene compounds such as budadiene or derivatives thereof, unsaturated carboxylic acid anhydrides such as maleic anhydride, itaconic anhydride, citraconic anhydride, N-methylmaleimide, N-butylmaleimide N-alkyl-substituted maleimide compounds such as N-cyclohexylmaleimide, N-phenylmaleimide, N-4-diphenylmaleimide, N-2-chlorophenylmaleimide, N-4-bromophenylmaleimide, N-1-naphthylmaleimide; It is done. These can be used alone or in admixture of two or more.

  Examples of the adhesive and adhesive resins include polyolefin resins, vinyl chloride resins, vinylidene chloride resins, vinyl alcohol resins, ethylene-vinyl alcohol copolymer resins, acrylic resins, and styrene-butadiene copolymer resins. , Natural rubber resins, chloroprene resins, and resins obtained by blending the above resins with tackifier resins such as rosins, rosin derivatives, petroleum resins, terpene resins, phenol resins, rosin phenol resins, ketone resins, etc. Examples thereof include a composition. These may be used alone or in combination of two or more.

  The structure of the non-foamed layer constituting the extruded foam laminate of the present invention is not particularly limited as long as the non-foamed layer contains a heat radiation inhibitor, and any structure of a single layer or multiple layers can be adopted.

The thickness of the non-foamed layer constituting the extruded foam laminate of the present invention is equal to the thickness of the foam laminate and the number of non-foamed layers in the foamed laminate (number of units comprising foamed layer / non-foamed layer / foamed layer). Although it is suitably selected according to this, 1 to 500 μm is preferable, 20 to 300 μm is more preferable, and 30 to 200 μm is particularly preferable.
When the thickness of the non-foamed layer is in the range of 1 to 500 μm, a foamed laminate having light weight and heat insulation can be obtained.

About the manufacturing method of the extrusion foaming laminated body of this invention, especially the lamination | stacking method of a foaming layer and a non-foaming layer, since it is excellent in productivity, it melt | dissolves the resin of a non-foaming layer and a foaming layer using a respectively different extruder. Kneading and laminating each molten resin in multiple layers, for example,
A method of repeating division and lamination after making a laminated flow composed of a plurality of layers described in JP-A-4-278323, etc.
Examples include a method in which a plurality of divided flows described in JP-T-2005-523831, JP-A-2004-249520, etc. are formed and then sequentially laminated.

As the structure of the extruded foam laminate of the present invention, it is necessary to have at least one structure comprising a foam layer / non-foam layer / foam layer in the thickness direction of the foam laminate, and foam layer / non-foam layer / foam As in layer / non-foamed layer / foamed layer, it is preferable to have a plurality of structures comprising foamed layer / non-foamed layer / foamed layer, more preferably 3 or more, and more preferably 5 or more.
By providing a plurality of non-foamed layers containing a heat ray radiation inhibitor in a foamed layer containing a heat ray radiation inhibitor in the thickness direction of the foamed laminate, a single foam layer containing the heat ray radiation inhibitor and one non-foamed layer An excellent thermal conductivity reduction effect that cannot be obtained with a foam laminate in which (heat radiation inhibitor) is laminated can be exhibited.

The thickness of the extruded foam laminate of the present invention is not particularly limited and is appropriately selected depending on the application.
For example, in the case of a heat insulating material used for a building material or the like, in order to impart a preferable heat insulating property, bending strength and compressive strength, the thickness of a normal plate-like material is less than a thin material such as a sheet. Some are preferred, usually 10 to 150 mm, preferably 20 to 100 mm.

The density of the extruded foam laminate of the present invention is preferably 45 Kg / ^{m 3} or less, more preferably 25~40Kg / ^{m 3} or less, more preferably 30~35Kg / ^{m 3} or less.
When the density of the extruded foam laminate is larger than 45 kg / m ³ , the lightness is inferior.

  The equivalent thermal conductivity at an average temperature of 20 ° C. after one week after the production of the extruded foam laminate of the present invention is preferably 0.028 W / m · K or less, more preferably 0.026 W / m · K or less, 0.024 W / m · K or less is particularly preferable.

  When the equivalent thermal conductivity is 0.028 W / m · K or less, the extruded foam laminate is suitably used as a building material application, and can contribute to providing a comfortable living space.

  The extruded foam laminate of the present invention has various uses from the viewpoint of excellent light weight and heat insulation properties, for example, building materials such as floor materials, wall materials, and roof materials, heat insulation materials for cold cars, vehicle bumpers, and automobiles. It can be suitably used for automobile interior members such as ceiling materials and civil engineering members such as antifreezing agents for the ground.

  Next, the present invention will be described in detail based on examples, but the present invention is not limited only to such examples. Unless otherwise specified, “%” represents wt%.

  Evaluation methods for Examples and Comparative Examples are as follows.

(1) Equivalent thermal conductivity of extruded foam laminate at an average temperature of 20 ° C. (unit: W / m · K)
The equivalent thermal conductivity of the obtained extruded foam laminate at an average temperature of 20 ° C. was measured according to JIS A9511 (2003).
For measurement, a thermal conductivity measuring device [HC-074 manufactured by Eihiro Seiki Co., Ltd.] was used, and three rectangular parallelepipeds of about 300 mm × 100 mm × 25 mm were cut out from the extruded foamed laminate, and these were arranged side by side to form 300 mm × 300 mm × 25 mm. It was set at −074 and measured.
In addition, the measurement was performed on the extruded foam laminate after one week after the 10 mm portion was deleted from the surface after production.

(2) Density of extruded foam laminate (unit: kg / m ³ )
The obtained extruded foam laminate is cut out of a rectangular parallelepiped having a length of about 200 mm × 100 mm width × 25 mm, and the weight is measured, and the length, width and thickness are measured using a caliper, and the density of the foam is measured. Was calculated by the following equation.
Density of extruded foam laminate (g / cm ³ ) = weight of foam laminate (g) / volume of foam laminate (cm ³ )
The calculated value was converted into a unit (Kg / m ³ ).

(3) Average cell diameter of the foam layer Using a digital microscope [manufactured by Sonic, BS-8000], an image obtained by enlarging the foam layer of the foam layer in the cross section in the thickness direction of the extruded foam laminate to 200 times is taken into a personal computer. After printing the image on paper, draw a straight line equivalent to 1 mm in actual dimensions in any thickness direction, count the number of bubbles crossing each straight line, and then calculate the bubble diameter in the thickness direction at each location. It calculated according to the formula of
Bubble diameter in the thickness direction = straight line length 1 mm / number of bubbles crossing the straight line Then, in another two places, the bubble diameter in the thickness direction is obtained by the same operation, and these values are arithmetically averaged. The average cell diameter in the vertical direction was used.

(4) Surface temperature and deformation evaluation of extruded laminate by infrared irradiation A rectangular parallelepiped sample having a width of 100 mm, a length of 100 mm and a thickness of 25 mm was cut out from the obtained extruded laminate and used as an infrared irradiation sample.
The sample surface was irradiated for 1 hour using an infrared lamp [Iwasaki Electric Co., Ltd., Eye R infrared bulb, 250 W] installed at a position of 200 mm to the sample for infrared irradiation, and then the surface temperature of the sample was measured Measurement was performed using an infrared radiation thermometer [ASONE, ISK-8700II].
The sample after infrared irradiation was placed on a plane, the height from the plane of the four corners of the sample was measured with a straight scale, and the largest value of the obtained four corners was taken as the amount of warpage. The warpage amount was evaluated according to the following criteria.
○: Warpage amount is 1 mm or less.
(Triangle | delta): The curvature amount is larger than 1 mm and 5 mm or less.
X: The amount of warpage is larger than 5 mm.

Example 1
[Method for producing molten resin containing foaming agent]
Polystyrene [manufactured by PS Japan Co., Ltd., trade name: G9401, MFR = 2.2 g / 10 min] 100 parts by weight, talc [manufactured by Hayashi Kasei Co., Ltd., trade name: TALCAN PAWDER PK-Z] 0.1 weight Parts, calcium stearate [manufactured by Sakai Chemical Industry Co., Ltd., trade name: calcium stearate] 0.3 parts by weight, liquid paraffin [manufactured by Shin Nippon Oil Co., Ltd., trade name: polybutene LV-50] 0.2 parts by weight, silicon oxide [Nippon Aerosil Co., Ltd., AEROSIL] 0.1 parts by weight Bentonite [Hojoen Co., Ltd., trade name: Bengel Bright 11] In a mixture of 1.0 parts by weight, titanium oxide-containing polystyrene resin [Ishihara Sangyo Co., Ltd. Company-made, trade name: Taipei R-780-2, titanium oxide content 88 wt%, average particle size 0.24 μm] And trends, titanium oxide-containing styrenic resin composition (content ratio of titanium oxide 4.0 wt%) was prepared.
The styrenic resin composition was supplied at 45.0 kg / hour to a two-stage extruder in which a first extruder having a diameter of 65 mm and a second extruder having a diameter of 90 mm were connected in series.
The styrenic resin composition supplied to the first extruder is heated to a resin temperature of 180 ° C. and kneaded. In the vicinity of the tip of the first extruder (side connected to the second extruder), as a foaming agent, A styrene resin obtained by melting 6.0% by weight of isobutane [manufactured by Mitsui Chemicals, Inc.] and 2.0% by weight of dimethyl ether [manufactured by Taiyo Liquefied Gas Co., Ltd.] with respect to 100% by weight of the styrene resin composition. Press fit into the composition. At this time, the resin pressure at the tip of the first extruder was 10.8 MPa, while the press-fitting pressure of the foaming agent was 13.1 MPa.
In the second extruder connected to the first extruder, after the resin temperature is cooled to 121 ° C., it is divided into three, and two types of molten resin containing a foaming agent are provided at the tip of the second extruder It supplied to the feed block for 5-layer multilayer lamination (made by Pla Giken Co., Ltd.).
[Method for producing molten resin containing no foaming agent]
Addition of 6 parts by weight of plasticizer dimethyl phthalate [manufactured by Daihachi Chemical Industry Co., Ltd., trade name: DMP] to 100 parts by weight of polystyrene [manufactured by PS Japan, trade name: 679, MFR = 18 g / 10 min] Thus, a dimethyl phthalate master batch was prepared in advance.
Dry blend of 80 parts by weight of the obtained dimethyl phthalate masterbatch and 20 parts by weight of carbon black masterbatch [manufactured by Sumika Color Co., Ltd., trade name: SPAB-851, carbon black content 40% by weight] And a carbon black-containing styrene resin composition (carbon black content ratio 8 wt%).
The carbon black-containing styrenic resin composition was supplied to an extruder having a diameter of 50 mm at 5.0 kg / hour. The supplied resin was heated to 140 ° C., melted and kneaded, divided into two, and supplied to the feed block for the two-type five-layer multilayer stack.
[Method for Producing Extruded Foamed Molded Body by Melting Melted Resin Containing Foaming Agent and Molten Resin Not Containing Foaming Agent in Thickness Direction]
A molten resin (two layers) that does not contain a blowing agent that is divided into two in the thickness direction under a pressure of 3.0 MPa in the feed block for the two types of five layers multilayer laminated at 135 ° C. Were merged at a thickness of 5 mm / 1 mm / 12 mm / 1 mm / 5 mm, respectively, so as to be sandwiched between molten resins (three layers) containing a blowing agent divided into three.
After that, it has a rectangular cross-section of 2.8 mm in thickness direction and 50 mm in width direction, and a merged multilayer flow is extruded into the atmosphere from a die lip temperature-controlled at 80 ° C., and a rectangular parallelepiped shape with a thickness of 24 mm and a width of 210 mm. Extrusion consisting of a 5-layer structure of foamed layer / non-foamed layer / foamed layer / non-foamed layer / foamed layer (each thickness is 5.5 mm / 0.2 mm / 12.6 mm / 0.2 mm / 5.5 mm) A foam laminate was obtained.
Table 1 shows the measurement results of the obtained samples.

(Example 2)
In [Method for producing molten resin containing no foaming agent]
3 parts by weight of carbon graphite [product name: X-10, scale-like, particle size 10 μm] and 100 parts by weight of dimethyl phthalate as a plasticizer are added to 100 parts by weight of polystyrene, Extruded foam laminates were obtained in the same manner as in Example 1 except that the carbon graphite-containing styrene resin composition (carbon graphite content ratio: 2.8% by weight) was used.
Table 1 shows the measurement results of the obtained samples.

(Example 3)
In [Production of molten resin containing foaming agent]
Alumina oxide paste [made by Showa Aluminum Powder Co., Ltd., trade name: SAP CS420] was used as a heat radiation suppressant, except that the alumina oxide-containing styrene resin composition having an alumina oxide content ratio of 5.0% by weight was used. Obtained an extruded foam laminate by the same operation as in Example 1.
Table 1 shows the measurement results of the obtained samples.

(Comparative Example 1)
[Method for producing molten resin containing foaming agent]
A styrene resin composition was prepared in the same manner as in Example 1 except that no radiation inhibitor was added.
The styrenic resin composition was supplied at 45.0 kg / hour to a two-stage extruder in which a first extruder having a diameter of 65 mm and a second extruder having a diameter of 90 mm were connected in series.
The styrenic resin composition supplied to the first extruder is heated to a resin temperature of 180 ° C. and kneaded. In the vicinity of the tip of the first extruder (side connected to the second extruder), as a foaming agent, With respect to 100% by weight of the styrene resin composition, 6.0% by weight of iso-butane and 2.0% by weight of dimethyl ether were press-fitted into the melted styrene resin composition. At this time, the resin pressure at the tip of the first extruder was 10.8 MPa, while the press-fitting pressure of the foaming agent was 13.1 MPa.
In the second extruder connected to the first extruder, after the resin temperature is cooled to 121 ° C., it is divided into two, and the molten resin containing the foaming agent is provided at the tip of the second extruder. It supplied to the feed block for 5 layer multilayer lamination.
[Method for producing molten resin containing no foaming agent]
A styrene resin composition was obtained in the same manner as in Example 1 except that the radiation inhibitor was not added.
The styrenic resin was supplied to an extruder having a diameter of 50 mm at 5.0 kg / hour. The supplied resin was heated to 140 ° C., melted and kneaded, and supplied to the feed block for the two-kind five-layer multi-layer stack without diversion.
[Method for Producing Extruded Foamed Molded Body by Melting Melted Resin Containing Foaming Agent and Molten Resin Not Containing Foaming Agent in Thickness Direction]
In the same manner as in Example 1, a molten resin containing a foaming agent and a molten resin not containing a foaming agent are merged in the thickness direction to form a foam layer / non-foam layer / foam layer in a rectangular parallelepiped shape having a thickness of 24 mm and a width of 210 mm. An extruded foam laminate having a five-layer structure consisting of / non-foamed layer / foamed layer was obtained.
Table 1 shows the measurement results of the obtained samples.

(Comparative Example 2)
[Method for producing molten resin containing foaming agent]
The same operation as in Example 1 was performed except that the styrene resin composition was prepared so that the carbon black content ratio was 4% by weight.
[Method for producing molten resin containing no foaming agent]
The same operation as in Example 1 was carried out except that the styrene resin composition was prepared so that the carbon black content ratio was 8% by weight.
[Method for Producing Extruded Foamed Molded Body by Melting Melted Resin Containing Foaming Agent and Molten Resin Not Containing Foaming Agent in Thickness Direction]
The same operation as in Example 1 was performed in a feed block for two types and five layers, and an extruded foam laminate was obtained.
Table 1 shows the measurement results of the obtained samples.

(Comparative Example 3)
In [Method for producing molten resin containing no foaming agent]
Except not having added the radiation inhibitor, operation similar to the comparative example 2 was performed and the extrusion foaming laminated body was obtained.
Table 1 shows the measurement results of the obtained samples.

(Comparative Example 4)
In [Method for producing molten resin containing no foaming agent]
The same operation as in Example 1 except that titanium oxide [manufactured by Ishihara Sangyo Co., Ltd., trade name: Taipei R-780-2] was added as a radiation inhibitor so that the content ratio of titanium oxide was 4.0% by weight. To obtain an extruded foam laminate.
Table 1 shows the measurement results of the obtained samples.

(Comparative Example 5)
[Method for producing an extruded foamed molded article by joining a molten resin containing a foaming agent and a molten resin not containing a foaming agent in the thickness direction]
A molten resin (two layers) containing a blowing agent divided into two in the thickness direction under a pressure of 3.0 MPa in the feed block for the two-type five-layer multi-layer laminated at a temperature of 135 ° C. A five-layer structure of non-foamed layer / foamed layer / non-foamed layer / foamed layer / non-foamed layer (each thickness is determined to be sandwiched between three molten resin containing no foaming agent (three layers). , 0.2 mm / 11.7 mm / 0.2 mm / 11.7 mm / 0.2 mm).
Table 1 shows the measurement results of the obtained samples.

(Comparative Example 6)
[Method for producing molten resin containing foaming agent]
A styrene resin composition was prepared in the same manner as in Example 1 except that titanium oxide was not added.
The styrenic resin composition was supplied at a rate of 50.0 kg / hour to a two-stage extruder in which a first extruder having a diameter of 65 mm and a second extruder having a diameter of 90 mm were connected in series.
The styrenic resin composition supplied to the first extruder is kneaded by heating to 180 ° C., and as a foaming agent near the tip of the first extruder (the side connected to the second extruder) With respect to 100% by weight of the resin composition, 6.0% by weight of iso-butane and 2.0% by weight of dimethyl ether were pressed into the melted styrene resin composition. At this time, the resin pressure at the tip of the first extruder was 11.1 MPa, while the press-fitting pressure of the foaming agent was 13.3 MPa.
In the second extruder connected to the first extruder, after the resin temperature is cooled to 121 ° C., it is divided into two, and the molten resin containing the foaming agent is provided at the tip of the second extruder. It supplied to the feed block for 5 layer multilayer lamination.
On the other hand, the molten resin containing no foaming agent was not supplied to the feed block for the two-kind five-layer multilayer lamination.
[Method for Producing Extrusion Foam Molded Body Only from Molten Resin Containing Foaming Agent]
In the feed block for the two-type five-layer multi-layer laminate, the temperature of which is adjusted to 135 ° C., only the molten resin containing the foaming agent is allowed to flow, and has a rectangular cross-section with a thickness direction of 2.8 mm and a width direction of 50 mm. From the die lip temperature-controlled at 80 ° C., it was extruded into the atmosphere to obtain an extruded foam having a rectangular parallelepiped shape having a thickness of 24 mm and a width of 210 mm and consisting only of a foam layer.
Table 1 shows the measurement results of the obtained samples.

From the results of Table 1, it can be seen that the thermal conductivity is reduced and the heat insulation performance is improved by including the white radiation inhibitor in the foam layer and including the black radiation inhibitor in the non-foam layer. Furthermore, since the foamed layer which comprises the thickness direction outermost layer of an extrusion foaming laminated body is white, it turns out that the temperature rise by solar radiation is suppressed and a deformation | transformation does not generate | occur | produce.

1 Foam layer 2 Non-foam layer

Claims (3)

A foam laminate having at least one structure in which a foam layer is laminated via a non-foam layer in the thickness direction,
The foam layer contains a white heat ray radiation inhibitor, the non-foam layer contains a black heat ray radiation inhibitor, and the foam layer is disposed on the outermost layer in the thickness direction.
The density of the laminated structure is 45 Kg / m ³ or less, and the equivalent thermal conductivity at an average temperature of 20 ° C. after one week has elapsed after production is 0.028 W / m · K or less, Polystyrene resin extruded foam laminate.   2. The polystyrene-based resin according to claim 1, wherein the white heat ray radiation inhibitor is titanium oxide and / or alumina oxide, and the black heat ray radiation inhibitor is carbon black and / or graphite. Extruded foam laminate. The polystyrene-based resin extruded foam laminate according to claim 1 or 2, wherein the extruded laminate foam is produced by a coextrusion method.

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