JP2012025815A - Extrusion foam-molded product exhibiting excellent heat insulating performance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an extrusion foam-molded product for a heat insulating material exhibiting remarkably improved insulating performance without using chlorofluorocarbons as a foaming agent.SOLUTION: The extrusion foam-molded product is obtained by combining at least one molten resin containing a foaming agent with at least one molten resin containing no foaming agent pressurized by a gear pump under a high pressure in the thickness direction, namely vertically, to form a laminated molten resin, then releasing the laminated molten resin under atmospheric pressure while extruding it in the flow direction, and continuously molding it while imparting thereto a shape having a given cross section in a mold, where the extrusion foam-molded product has a structure comprising foamed layers laminated via a non-foamed layer in the thickness direction and the foamed layer is composed of cells having an average cell size of 0.10-0.25 mm.

Description

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

  Conventionally, the multilayer extrusion foaming composed of a foamed layer / non-foamed layer has been studied mainly in the form of a film and a sheet using a polypropylene resin (for example, Patent Documents 1 to 4).

  In addition, there is a study example of multilayer extrusion foaming composed of a foamed layer / non-foamed layer focusing on a polystyrene-based extruded foam board (Patent Documents 5 and 6).

  Patent Document 5 is a technique for obtaining a foamed molded article by integrating a molten resin containing a water-containing foaming agent and a molten resin including a brominated aliphatic flame retardant, and then extruding the composite flow from a die to a low-pressure zone. When it comes into contact with water in a high temperature region, it is possible to use a brominated aliphatic flame retardant that generates an acidic decomposition product and causes corrosion of equipment by acidification of the resin, and a water-containing foaming agent.

  This technology focuses on fire resistance, and there is no suggestion about heat insulation and heat insulation performance, which are general uses of polystyrene-based extruded foam boards. In fact, the improvement in fire resistance in the description of the examples is that of bromine. In addition to the increase in the total content, a tendency to be caused by an increase in the density of the composite structure, which is disadvantageous to the heat insulation performance, is recognized, and thus it is estimated that the technique is not focused on the heat insulation performance improvement.

  Patent Document 6 is a coextruded foamed composite, which is a technique for adding an additive such as carbon black to a non-foamed layer to reduce thermal conductivity. However, the blowing agents used are chlorofluorocarbons, which are required to be completely abolished from the viewpoint of protecting the global environment, and in order to achieve heat insulation performance without using chlorofluorocarbons as the blowing agent. Need to be improved.

  As a technique for improving the heat insulation property of polystyrene-based extruded foam board without using chlorofluorocarbon as a foaming agent, it is known to have a cell structure composed of small cells and large cells (for example, Patent Documents 7 to 9). ).

However, in recent years, with increasing demand for comfort and energy saving in living spaces, there has been a demand for further improvement of heat insulation performance of conventional heat insulating materials obtained using the techniques of Patent Documents 7 to 9, and chlorofluorocarbon as a blowing agent. At present, there is a demand for the development of an extruded foam board having high heat insulation performance without using any kind.
Japanese Patent Laid-Open No. 10-748 JP-T-4-505594 Japanese Examined Patent Publication No. 7-98349 WO2008 / 008875 publication Japanese Patent No. 3474568 Japanese National Patent Publication No. 6-510247 JP 2007-321068 A JP 2005-514506 A JP 2004-277673 A

  This invention solves the said subject, and it aims at providing the extrusion foaming molding for heat insulating materials which has a remarkable improvement effect of heat insulation performance, without using chlorofluorocarbons 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.
(1) When a molten resin containing a blowing agent and a molten resin not containing a blowing agent are merged in the thickness direction (vertical direction) under high pressure to produce a laminated molten resin, the molten resin not containing the blowing agent is removed by a gear pump. Adjustment of the cell diameter of the foam layer constituting the multilayer extrusion foam molded article obtained by increasing the pressure and adjusting the resin pressure of the molten resin not containing the foaming agent to release the laminated molten resin under atmospheric pressure Is possible.
(2) The heat insulation performance is improved by suppressing the average cell diameter in the thickness direction of the foamed layer to 0.25 mm or less.

That is, the present invention
[1] at least one molten resin containing a blowing agent; and
At least one molten resin containing no foaming agent that has been pressurized by a gear pump;
Obtained by continuously forming the laminated molten resin obtained by merging in the vertical direction, which is the thickness direction under high pressure, by releasing it under atmospheric pressure while extruding it in the flow direction, and shaping it into a constant cross section with a mold. An extruded foam molded article,
The extruded foam molding has a structure in which a foam layer is laminated via a non-foam layer in the thickness direction, and the foam layer is composed of bubbles having an average cell diameter in the thickness direction of 0.25 mm or less. Extruded foam molded product, characterized by
[2] The extruded foam molded article according to [1], wherein the density of the extruded foam molded article is 20 to 65 kg / m ³ .
[3] The extruded foam molded article according to [1] or [2], wherein the density of the extruded foam molded article is 20 to 40 kg / m ³ .
[4] The extruded foam molded article according to any one of [1] to [3], wherein an average cell diameter in the thickness direction of the foamed layer is 0.10 to 0.25 mm,
[5] Any one of [1] to [4], wherein the extruded foam-molded product has a plurality of the structures in which a foam layer is laminated via a non-foam layer in the thickness direction. Extruded foam molded product according to
[6] The resin constituting the foamed layer is one or more resins selected from the group consisting of polystyrene, styrene-acrylonitrile copolymers, styrene-acrylic acid copolymers, and modified polyphenylene ether resins. An extruded foam molded article according to any one of [1] to [5],
[7] The extruded foam molded article according to [6], wherein the resin constituting the foamed layer is polystyrene, and
[8] Any one of [1] to [7], wherein one or more hydrocarbons selected from propane, normal butane, isobutane and cyclopentane are contained in the bubbles constituting the foam layer. Extruded foam molded product according to any one of the above,
About.

  The effects of the foamed laminated structure of the present invention are as follows.

  When a molten resin containing a blowing agent and a molten resin not containing a blowing agent are joined together in the thickness direction (vertical direction) under high pressure to produce a laminated molten resin, the molten resin containing no blowing agent is pressurized by a gear pump, By adjusting the resin pressure of the molten resin containing no foaming agent, it becomes possible to adjust the cell diameter of the foam layer constituting the multilayer extrusion foamed molded article obtained by releasing the laminated molten resin under atmospheric pressure, The average cell diameter in the thickness direction of the foamed layer can be controlled in the range of 0.10 to 0.25 mm, thereby improving the heat insulation performance of the multilayer extrusion foamed molded product.

  Since the above effect can be combined with other conventional techniques aimed at improving the heat insulating properties of the foam molded article, it is expected to provide an extruded foam molded article having an unprecedented excellent heat insulation performance.

FIG. 1 is a schematic view showing a configuration of an apparatus for producing an extruded foam molded body according to an embodiment of the present invention. FIG. 2 is a schematic diagram relating to a laminated structure of an extruded foam molded body according to an embodiment of the present invention. FIG. 3 is a schematic diagram showing the measurement position of the thickness of the extruded foam molded body according to the embodiment of the present invention. FIG. 4 is a schematic diagram showing the measurement position of the width of the extruded foam molded body according to the embodiment of the present invention.

  As shown in FIG. 1, the apparatus for producing an extruded foam molded body according to an embodiment of the present invention has a fixed cross section with a mold while extruding a heat-plasticized molten resin in a flow direction (see arrow in the figure). The shape is adjusted and continuously formed.

The manufacturing apparatus is an apparatus including a foaming extruder 1, a non-foaming extruder 2, a gear pump 3, a laminating apparatus 4, a laminating / doubling apparatus 5, a molding die 6, and a molding machine 7.
Here, the foaming extruder 1 is an extruder that kneads a thermoplastic resin (added with an additive if necessary), pressurizes and supplies a molten resin containing a foaming agent having a foaming agent press-fitting and cooling mechanism. It is.
The non-foaming extruder 2 is an extruder that pressurizes and supplies a molten resin that has a kneading mechanism and does not contain a foaming agent.
The gear pump 3 is a gear pump that adjusts the resin pressure of the molten resin that does not contain the blowing agent supplied from the non-foaming extruder 2 and supplies it quantitatively.
The laminating apparatus 4 has at least one molten resin containing a blowing agent supplied from the foaming extruder 1 and at least one molten resin not containing a blowing agent supplied from the gear pump 3 in the vertical direction which is the thickness direction. It is a laminating apparatus that joins to form a laminated molten resin, and examples thereof include a feed block.
The doubling apparatus 5 divides the laminated molten resin at the center in the left-right direction, which is the width direction, to form two divided laminated resins, and merges these divided laminated molten resins so as to overlap each other. It is an apparatus for making a laminated molten resin (hereinafter, the lamination apparatus 4 and the lamination doubling apparatus 5 may be collectively referred to as “multilayer lamination apparatus 8”).
The molding die 6 is a molding die that is doubled by releasing the laminated molten resin or the doubled laminated molten resin under atmospheric pressure to vaporize the foaming agent.
The molding machine 7 is a molding machine that takes a foam molded body and cools it while constraining it in the vertical direction to obtain a final shape.
Note that the lamination doubling device 5 is not necessarily an essential device in the present invention, and can increase the number of layers efficiently. Therefore, the lamination doubling device 5 should be used when producing an extruded foam molded body having a large number of layers. Is a preferred device.

  When producing an extrusion foamed molded article using the production apparatus shown in FIG. 1, when the foaming agent in the molten resin containing the foaming agent foams in the flow path through which it is released under atmospheric pressure, In the foamed layer, cell enlargement and low closed cell ratio occur, and the obtained extruded foamed product tends not to exhibit the effect of reducing the thermal conductivity expected by multilayering.

  Therefore, the laminating apparatus 4 without a pressing mechanism such as an extruder, the laminating doubler 5 and the molding die 6 (hereinafter, the laminating apparatus 4 and the laminating doubler 5 are collectively referred to as the molding die 6, It may be referred to as “multilayer foaming device 9”.) It is necessary to keep the inside at a resin pressure that does not foam in the flow path.

  However, the multi-layer foaming apparatus 9 has a complicated flow path shape and a long flow path length, so that the pressure loss is large, and the multi-layer foaming apparatus 9 can be obtained only by pressurization by the foaming extruder 1 and the non-foaming extruder 2. 9 tends to be difficult to maintain the pressure. Operations such as increasing the discharge rate to maintain the pressure in the multilayer foaming device 9, decreasing the resin temperature in the multilayer foaming device 9 and increasing the resin melt viscosity, and narrowing the resin flow path of the molding die 6 When the resin pressure of the foaming extruder 1 and the non-foaming extruder 2 is increased, the foaming agent is unstablely press-fitted, the resin supply is unstable, the extruder is damaged due to overload, and the like. there is a possibility.

  The gear pump used in the present invention is classified as a constant displacement pump capable of obtaining a constant flow rate, and is a two-row gear type comprising one drive gear and one free gear; one drive gear and two There are three types of gears composed of a single free gear; a planetary gear type composed of one drive gear and a plurality of free gears;

As its principle, a certain amount of discharge is secured by the actions (1) to (3).
(1) When the meshing of the gear is released by rotation at the inlet of the gear pump, the gear tooth gap is filled with molten resin.
(2) The molten resin collected in the tooth gap is confined by the casing and the side plate, and moves in the direction of the outlet along the inside of the casing according to the rotation.
(3) When the gear teeth mesh with each other at the outlet, the molten resin is pushed out and discharged by a certain amount.
Therefore, even if there is a slight fluctuation in the resin pressure at the tip portion of the extruder, the fluctuation of the downstream resin pressure is very small because the gear pump absorbs the fluctuation by using the gear pump.

  In order to improve the quantitative supply performance by the gear pump, a method of controlling the pressure before the gear pump to be constant by changing the rotation speed of the screw of the extruder is preferable.

The gear pump 3 used in the present invention has a function of supplying a molten resin not containing a foaming agent quantitatively to the laminating device 4 and a melt containing no foaming agent in order to maintain the resin pressure in the multilayer foaming device 9. It plays a role of increasing the resin pressure of the resin and supplying it to the laminating apparatus 4 in a state where pressure fluctuation is suppressed.
In addition, the molten resin not containing the foaming agent is added to the laminating apparatus 4 by using the gear pump and adjusting the viscosity of the molten resin not containing the foaming agent, adjusting the plasticizer amount, adjusting the resin temperature, etc., or adjusting the discharge amount. It is possible to adjust the resin pressure at the time of being supplied to the.

  As a result, the resin pressure in the laminated foaming device 9 can be adjusted, and the cell diameter of the foamed layer constituting the extruded foamed article can be controlled.

  The meaning of obtaining an extrusion foamed molded article by the coextrusion method in which a molten resin containing a foaming agent and a molten resin not containing a foaming agent are merged in the thickness direction and released under atmospheric pressure is economical. In addition to such advantages, the non-foamed layer suppresses the intrusion of air into the foamed layer cell, which is caused by the reduced internal pressure of the cells constituting the foamed layer, as the temperature of the molded body decreases immediately after production. This is because high heat insulation is expected.

  Furthermore, by adopting a structure in which both sides of the foam layer are covered with the non-foam layer in the thickness direction, the infiltration of air from the outside air into the foam layer cell is suppressed, and the heat insulation performance of the resulting foam is further improved. be able to.

  Moreover, the meaning of making it merge in the thickness direction is because the structure which is easy to express the reduction effect of the heat conductivity expected by multilayering can be obtained. This is because the heat conductivity of the heat insulating material is measured in the thickness direction of the heat insulating material as defined in JIS A9511. Therefore, the presence of a plurality of non-foamed layers in the thickness direction results in radiation heat transfer between the foam layers. This is because an effect of suppressing gas is expected, and an effective gas barrier effect is expected by increasing the area of the non-foamed layer covering the foamed layer.

  For this reason, the extrusion foaming molding obtained by making the molten resin containing a foaming agent and the molten resin which does not contain a foaming agent merge in a thickness direction becomes a thing with favorable heat insulation with low heat conductivity.

  On the other hand, when they are merged in the left-right direction, the resulting extruded foamed molded product transfers heat in the non-foamed layer, which has a higher thermal conductivity than the foamed layer (acts as a thermal bridge), so the thermal conductivity is low. It tends to be high and inferior in heat insulation performance.

  The method for joining and laminating each molten resin in a multilayer form in the multilayer laminating apparatus 8 is not particularly limited, and a method using the laminating apparatus 4, for example, a feed block method generally used in a co-extruded film, Multi-manifold method: A laminating device 4 described in Japanese Patent Publication No. Sho 54-23025, Japanese Patent Laid-Open No. 4-278323, etc. is used to create a laminar flow consisting of a plurality of layers, The method of repeating lamination | stacking; after making the some division | segmentation flow as described in Japanese translations of PCT publication No. 2005-523831, Unexamined-Japanese-Patent No. 2004-249520, etc., the method of laminating sequentially is mentioned.

  The temperature of the multi-layer laminating apparatus 8 when manufacturing the extruded foam molded body is preferably equal to or less than ± 10 ° C. even if it is equal to or different from the resin temperature of the foaming agent-containing molten resin supplied to the multi-layer laminating apparatus 8. When the temperature difference is ± 10 ° C. or less, molding processing in an appropriate foaming temperature region is possible, and an extruded foam molded article having a foam layer having a high magnification and a high closed cell ratio can be obtained.

  The pressure in the multi-layer laminating apparatus 8 when manufacturing the extruded foam molded body is set to a pressure at which the foaming agent-containing molten resin supplied to the multi-layer laminating apparatus 8 does not cause foaming in the multi-layer laminating apparatus 8 and is adjusted by the gear pump 3. Is done. However, the pressure at which foaming does not occur in the multilayer laminating apparatus 8 depends on the type of foaming agent, the amount of foaming agent, and the temperature of the foaming agent-containing molten resin, and thus cannot be set unconditionally.

  In the present invention, the foam molding method using the molding die 5 is not particularly limited. For example, 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 forming a plate-like foam having a large cross-sectional area can be used.

Regarding the melt-kneading of the constituent resin of the foam layer using the foaming extruder 1,
(I) The thermoplastic resin is mixed with a foaming agent and, if necessary, the additive, and then heated and melted.
(Ii) After mixing one or more selected from the above-mentioned additives as necessary with a thermoplastic resin, the mixture is heated and melted, and the remaining additive is liquefied or melted as it is or as necessary. Add and mix by heating.
(Iii) A thermoplastic resin is mixed with one or more additives selected from the above-mentioned additives as necessary, and then a heat-melted composition is prepared, and then the composition and the remaining additives If necessary, the thermoplastic resin is mixed again, supplied to the extruder 1 and melted by heating.
Etc., thermoplastic resin, if necessary, supply the additive to a hot melt extruder,
Thereafter, a foaming agent is added to the thermoplastic resin under high pressure conditions at an arbitrary stage to form a fluid gel. Thereafter, the fluid gel is cooled to a temperature suitable for extrusion foaming and then supplied to the laminating apparatus 4.

There are no particular limitations on the heating temperature, melt kneading time, and melt kneading means when heating and kneading the thermoplastic resin and an additive such as a foaming agent.
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 amount of extrusion per unit time, the melt-kneading means, etc., and thus cannot be generally determined, but 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.

Further, regarding the melt-kneading of the constituent resin of the non-foamed layer using the non-foaming extruder 2, 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 above-mentioned additives as necessary, and then a heat-melted composition is prepared, and then the composition and the remaining additives , If necessary, mix the thermoplastic resin again, supply to the extruder and melt by heating,
For example, a thermoplastic resin, and if necessary, the additive is supplied to an extruder and heated and melt-kneaded. Thereafter, the melt-kneaded product is supplied to the multilayer laminating apparatus 8.

There are no particular limitations on the heating temperature, melt kneading time, and melt kneading means when the thermoplastic resin and additive are heat melt kneaded.
The heating temperature may be equal to or higher than the temperature at which the thermoplastic resin to be used melts, but the temperature difference is within ± 10 ° C. even if it is equal to or different from the set temperature of the multilayer laminating apparatus 8 to which the molten resin is supplied. It is preferable. When the temperature difference is ± 10 ° C. or less, it is possible to obtain a good extruded foamed article having no bubble breakage at the interface portion between the foamed layer and the non-foamed layer and no adhesion failure.
The melt-kneading time varies depending on the amount of extrusion per unit time, the melt-kneading means, etc., and thus cannot be generally determined, but the time required for uniformly dispersing and mixing the thermoplastic resin and the additive 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 resin extrusion. 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.

  The extruded foam molded body of the present invention has a structure in which a foam layer is laminated in the thickness direction via a non-foam layer, and the average cell diameter in the thickness direction is controlled in the range of 0.10 to 0.25 mm. By doing, the foaming molding excellent in the heat insulation performance can be obtained.

  As the structure of the extrusion foamed molded article of the present invention, a foamed layer is laminated through a non-foamed layer in the thickness direction of the extruded foamed molded article as shown in FIG. 2 (a): foamed layer / non-foamed layer / foamed layer. It is preferable to have a structure of This is because in the structure in which the foam layer is laminated on both sides of the non-foam layer, the non-foam layer has a larger thickness than the cell thickness of the cell constituting the foam layer. This is because the conductivity reduction effect works effectively. In addition, in a structure in which a foam layer is laminated only on one side of the non-foam layer, such as a non-foam layer / foam layer / non-foam layer, the effect of reducing thermal conductivity due to suppression of radiant heat transfer by the non-foam layer is sufficient. There is a tendency not to develop.

  As the structure of the extruded foam molded body of the present invention, it is more preferable that there are a plurality of non-foamed layers such as foamed layer / non-foamed layer / foamed layer / non-foamed layer / foamed layer shown in FIG. . This is because by providing a plurality of non-foamed layers in the thickness direction of the extruded foam molded article, an excellent thermal conductivity reduction effect that cannot be obtained with a single non-foamed layer is exhibited.

The foam layer constituting the extruded foam molded body of the present invention refers to a layer having a cell structure in which a plurality of cells are bonded by cell walls and cell wall joints (struts). 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 can be obtained because it easily exhibits heat insulation performance and can impart lightness to an extruded foam molded body. Shape is preferred.
The density of the foamed layer is preferably 500 kg / m ³ or less, although it depends on the density of the target extruded foam molded article.

The foamed layer constituting the extruded foamed article of the present invention needs to have a cell structure having an average cell diameter in the thickness direction of 0.25 mm or less, and an average cell diameter in the thickness direction of 0.10 to 0.00. It preferably has a 25 mm cell structure, and more preferably has a cell structure having an average cell diameter in the thickness direction of 0.10 to 0.20 mm.
A molded body having a cell structure in which the foam layer has a cell structure having an average cell diameter in the thickness direction of 0.25 mm or less is excellent in heat insulation. In addition, when it becomes a bubble structure whose average cell diameter of the thickness direction is 0.10 mm or less, the thickness of the bubble wall and the bubble wall bonding part becomes thin, and the radiation suppression effect by the heat ray passing through the cell wall and the bubble wall bonding part May be reduced and heat insulation may be deteriorated.

Here, the average cell diameter (A1) in the thickness direction is obtained as follows.
(1) A cross-sectional photograph of the foam layer located in the central portion is taken at a magnification of 20 to 200 times using a microscope, such as a micro high scope or a scanning electron microscope. At this time, the thickness direction is taken in the vertical direction and the extrusion direction is taken in the horizontal direction. The magnification is appropriately selected depending on the bubble diameter.
(2) Three arbitrary 2000 μm straight lines are drawn in the longitudinal direction of the cross-sectional photograph, and the number (X1) of bubbles in contact with the straight lines is measured. The average bubble diameter (A1) in the thickness direction of the bubbles is obtained by the following formula.
A1 [unit: μm] = 2000 × 3 ÷ number of bubbles (X1)

In the present invention, as a method of controlling the average cell diameter in the thickness direction in the foamed layer in the extruded foamed molded product, while using a gear pump, the resin selection of the molten resin not containing the foaming agent, the plasticizer amount adjustment, It is preferable to adjust by adjusting the resin pressure when the molten resin not containing the foaming agent is supplied to the laminating apparatus 4 by adjusting the viscosity by adjusting the resin temperature or the like, or adjusting the discharge amount.
As another method for controlling the average cell diameter in the thickness direction of the foam layer, (a) silica, talc, calcium silicate, wollastonite, kaolin, clay, mica, zinc oxide, titanium oxide, calcium carbonate, sodium bicarbonate Nucleating agents represented by inorganic compounds such as, and a method of adding layered silicate to styrene-based resins and adjusting them by the amount added,
(B) a method of adjusting according to the type, composition and addition amount of the foaming agent,
Furthermore, (c) depending on the screw shape of the extruder as the melt kneading means, the heating temperature, the pressure, the amount of the melt-kneaded styrene resin composition discharged from the die lip, the die shape, the resin temperature at the time of discharge, etc. The method of adjusting is also mentioned.
However, these methods tend to greatly affect the expansion ratio, closed cell ratio, cell flatness (cell diameter in the flow direction / cell diameter in the thickness direction) and the like. There is a tendency to be less convenient.

  On the other hand, the cell diameter control method by resin pressure control when supplying to the laminating apparatus 4 using a gear pump has an effect on the expansion ratio, closed cell ratio, cell flatness ratio, etc. compared to the cell diameter control method described above. It is an excellent method that can easily make fine adjustment of the cell diameter.

As described above, the density of the foamed layer in the present invention is not particularly limited as long as it is 500 kg / m ³ or less. However, in order to impart lightweight heat resistance, bending strength, and compressive strength, 20 it is preferably ~65kg / ^{m 3,} more preferably from 20 to 50 kg / ^{m 3,} more preferably 20~40kg / ^{m 3.} When the density of the foamed layer is in the range of 20 to 60 kg / m ³ , a foamed molded article excellent in mechanical properties such as light weight and compressive strength and heat insulation can be obtained.

The resin constituting the foamed layer of the extruded foamed molding of the present invention (hereinafter sometimes referred to as “foamed layer constituting resin”) is arbitrarily selected from thermoplastic resins that can be extruded and foamed.
Examples of the thermoplastic resin include polystyrene, styrene-acrylonitrile copolymer, styrene- (meth) acrylic acid copolymer, styrene- (meth) acrylic acid ester copolymer and other styrene resins, polymethyl methacrylate, poly Vinyl resins such as acrylonitrile resin and polyvinyl chloride resin; Polyolefin resins such as polypropylene, polyethylene, ethylene-propylene copolymer, ethylene-propylene-butene terpolymer, and cycloolefin (co) polymer Polyolefin resins whose rheology is controlled by introducing a branched structure or a crosslinked structure into them; Polyamide resins such as nylon 6, nylon 66, nylon 11, nylon 12, MXD nylon; polyethylene terephthalate, polybutylene terf Polyester resins such as rate and polyarylate; polycarbonate resins, polyphenylene ether resins, modified polyphenylene ether resins, polyoxymethylene resins, polyphenylene sulfide resins, polyphenylene sulfide resins, aromatic polyether resins, polyethers Examples include engineering plastics such as ether ketone resins and liquid crystal resins; aliphatic polyester resins such as polylactic acid, and these can be used alone or in admixture of two or more.

  When a styrene-based resin is used as the resin constituting the foamed layer of the extruded foam molded body of the present invention, it is not particularly limited. For example, a styrene homopolymer obtained from only a styrene monomer, a styrene monomer and styrene Examples thereof include random, block or graft copolymers obtained from copolymerizable monomers or derivatives thereof, post-brominated polystyrene, modified polystyrene such as rubber-reinforced polystyrene, ABS resin, and the like. These can be used alone or in admixture of two or more.

  Examples of the monomer copolymerizable with styrene include styrene such as methylstyrene, dimethylstyrene, ethylstyrene, diethylstyrene, isopropylstyrene, bromostyrene, dibromostyrene, tribromostyrene, chlorostyrene, dichlorostyrene, and trichlorostyrene. Derivatives; polyfunctional vinyl compounds such as divinylbenzene; (meth) acrylic such as acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, methacrylonitrile, α-chloroacrylonitrile, acrylonitrile Compounds; diene compounds such as budadiene or derivatives thereof; unsaturated carboxylic acid anhydrides such as maleic anhydride, itaconic anhydride, citraconic anhydride; N-methylmaleimide, N-butylmer N-alkyl substituted maleimide compounds such as imide, N-cyclohexylmaleimide, N-phenylmaleimide, N-4-diphenylmaleimide, N-2-chlorophenylmaleimide, N-4-bromophenylmaleimide, N-1-naphthylmaleimide; Can be given. These can be used alone or in admixture of two or more.

  Among these, as the resin constituting the foam layer of the extruded foam molded body of the present invention, polystyrene, styrene-acrylonitrile can be obtained because an extruded foam molded body that is easy to extrusion foam molding, lightweight, and excellent in heat insulation can be obtained. Copolymer, styrene- (meth) acrylic acid copolymer, styrene- (meth) acrylic ester copolymer, maleic anhydride modified polystyrene, styrene-unsaturated dicarboxylic anhydride-N-alkyl substituted maleimide copolymer Styrene resins such as coalesced and impact-resistant polystyrene, or vinyl resins such as polymethyl methacrylate and polyvinyl chloride resins; modified polyphenylene ether resins that are mixed resins of polystyrene resins and polyphenylene ether resins are preferred. Most preferred is a polystyrene homopolymer.

  The foamed layer of the extrusion foamed molded article of the present invention is obtained by press-fitting a physical foaming agent into a foamed layer-constituting resin in a molten state under high pressure and opening it to a low pressure region.

  The physical blowing agent to be injected in the present invention is not particularly limited, and examples thereof include saturated hydrocarbons having 3 to 5 carbon atoms such as propane, n-butane, i-butane, n-pentane, i-pentane, and neopentane; 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, methyl ethyl ketone, diethyl ketone, methyl n-propyl ketone, Ketones such as methyl n-butyl ketone, methyl i-butyl ketone, methyl n-amyl ketone, methyl n-hexyl ketone, ethyl n-propyl ketone, ethyl n-butyl ketone; methanol, ethanol, propyl alcohol 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, propyl acetate, acetic acid Examples thereof include esters such as butyl, amyl acetate, methyl propionate, and ethyl propionate; alkyl halides such as methyl chloride and ethyl chloride; inorganic blowing agents such as nitrogen, air, and carbon dioxide. These foaming agents can be used alone or in admixture of two or more.

  Among the foaming agents, hydrocarbons such as propane, n-butane, i-butane, n-pentane, i-pentane, neopentane, and cyclopentane are preferable because they can achieve both extrusion foam moldability and high heat insulation. Moreover, ethers such as dimethyl ether, diethyl ether and methyl ethyl ether; methanol, ethanol, propyl alcohol, i-propyl alcohol, butyl alcohol, i-butyl alcohol, t -Alcohols such as butyl alcohol; alkyl halides such as methyl chloride and ethyl chloride are preferred. Furthermore, inorganic foaming agents such as nitrogen, air, carbon dioxide and the like are preferable from the viewpoint of nonflammability and excellent environmental compatibility.

  The amount of the physical type foaming agent that is press-fitted into the melted foam layer-constituting resin (thermoplastic resin) is appropriately selected according to the setting value of the foaming ratio, etc. It is preferable to set it as 1-20 weight part with respect to 100 weight part of plastic resins, and it is more preferable to set it as 3-8 weight part. When the total amount of the physical foaming agent is 1 to 20 parts by weight, there is no void in the foamed molded product, and a foamed layer having an appropriate foaming ratio that can control flame retardancy is obtained. As a result, characteristics such as light weight and heat insulation are exhibited.

  The pressure when the foaming agent is press-fitted is not particularly limited as long as it is higher than the internal pressure of an extruder or the like.

  In the production of the foamed layer constituting the extruded foam molded body of the present invention, as 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, colorants such as antistatic agents and 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 thickness of the foamed layer constituting the extruded foamed molded product of the present invention is equal to the thickness of the extruded foamed molded product and the number of foamed layers in the extruded foamed molded product (number of units composed of foamed layer / non-foamed layer / foamed layer). It is selected as appropriate.

The non-foamed layer constituting the extruded foamed molded article of the present invention refers to a layer having a thickness 1.1 times or more larger than the thicker portion of the bubble wall or bubble wall bonding portion constituting the foam layer. . The density of the non-foamed layer depends on the density of the resin and additives used, but is preferably more than 500 kg / m ³ . The non-foamed layer may contain fewer bubbles than the foamed layer.

  The resin or resin composition constituting the non-foamed layer in the present invention (hereinafter sometimes referred to as “non-foamed layer-constituting resin”) was obtained in order to obtain the desired highly heat-insulated extruded foam molded product. Since it is preferable that the foamed layer and the non-foamed layer of the extruded foamed article are bonded well, it is preferable to select a resin that is compatible with the resin constituting the foamed layer.

  The thermoplastic resin having compatibility with the resin constituting the foamed layer is not particularly limited, and examples thereof include styrene resins such as polystyrene; polyolefin resins such as polypropylene, polyethylene, and ethylene propylene random copolymer; nylon 6 Polyamide resins such as nylon 66 and nylon 12; polyester resins such as polyethylene terephthalate and polybutylene terephthalate; polycarbonate resins; polyphenylene ether resins, modified polyphenylene ether resins; polyoxymethylene resins, polyarylate resins, polyphenylenes Examples include sulfide resins, polyacrylonitrile, polyvinyl alcohol, ethylene-vinyl acetic acid copolymers, polyacrylic acid, polymethyl methacrylate, and thermoplastic phenol resins. These may be used alone or in combination. Among these, polystyrene resins, polyolefin resins, polyphenylene ether resins, and modified polyphenylene ether resins are preferred because they are excellent in compatibility with the resin constituting the foam layer and are easy to mold. A resin is more preferable.

  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 alone or in admixture of two or more.

  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 alone or in admixture of two or more.

  In particular, when a styrene resin is used as the non-foamed layer constituting the extruded foam molded body of the present invention, styrene homopolymer, styrene acrylonitrile copolymer, (meth) acrylic acid from the viewpoint of compatibility with the foamed layer. It is more preferable to use a copolymerized polystyrene, a maleic anhydride-modified polystyrene, a styrene-unsaturated dicarboxylic anhydride-N-alkyl-substituted maleimide copolymer, and an impact-resistant polystyrene, and most preferably a styrene homopolymer.

  Examples of 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 copolymers. Resins, natural rubber resins, chloroprene resins, and resins obtained by blending the above resins with rosins, rosin derivatives, petroleum resins, terpene resins, phenol resins, rosin phenol resins, ketone resins, etc. Examples thereof include compositions.

  The non-foamed constituent resin is a thermoplastic resin type, molecular weight, copolymerization component so as to obtain a desired melt viscosity for the purpose of adjusting the resin pressure when being supplied to the laminating apparatus 4 in a molten state by a gear pump. It is preferable to select a copolymerization ratio and the like.

The structure of the non-foamed layer constituting the extruded foam molded body of the present invention is not particularly limited, and any structure of a single layer or multiple layers can be adopted.
The thickness of the non-foamed layer constituting the extruded foamed molded product of the present invention is the thickness of the extruded foamed molded product and the number of foamed layers in the extruded foamed molded product (number of units comprising foamed layer / non-foamed layer / foamed layer). Is suitably selected according to the range, preferably 10 to 500 μm, more preferably 20 to 300 μm, particularly preferably 30 to 200 μm, and most preferably 40 to 100 μm. When the thickness of the non-foamed layer is in the range of 10 to 500 μm, an extruded foam molded product having lightness and heat insulation can be obtained.

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

  Among these additives, the plasticizer does not disturb the flow at the resin joining interface during the production of the extruded foamed molding of the present invention, and the melt viscosity of the non-foamed layer-constituting resin contains a foaming agent. It works effectively when making adjustments close to the melt viscosity of the resin. Further, it works to effectively control the resin pressure when the resin is supplied to the laminating apparatus 4 using a gear pump by adjusting the melt viscosity of the resin by the addition amount. It is preferable.

The plasticizer added to the non-foamed layer constituting resin is not particularly limited, and any compound generally used as a plasticizer can be used. For example, dimethyl phthalate (DMP), diethyl phthalate (DEP) ), Dibutyl phthalate (DBP), di-2-ethylhexyl phthalate (DOP), dinormaloctyl phthalate (DNOP), diisononyl phthalate (DINP), dinonyl phthalate (DNP), diisodecyl phthalate (DIDP), butyl benzyl phthalate (BBP), phthalic acid esters such as phthalic acid混基ester _(C 6 _{~C 11);} dioctyl adipate (DOA), diisononyl adipate (DINA), dialkyl adipate (C6,8,10 ) (610A), dialkyl adipate _{(C 7, C 9) (} 79A) Azerai Dioctyl acid (DOZ) dibutyl sebacate (DBS), dioctyl sebacate (DOS), tricresyl phosphate (TCP), tributyl acetylcitrate (ATBC), epoxidized soybean oil (ESBO), trioctyl trimellitic acid (TOTM), Non-phthalic acid esters such as chlorinated paraffin, and the like.

  The amount of plasticizer added to the non-foamed layer constituting resin is appropriately selected depending on the target melt viscosity, but is preferably 1 to 20 parts by weight, and 2 to 15 parts by weight with respect to 100 parts by weight of the non-foamed layer constituting resin. More preferred is 3 to 12 parts by weight, and most preferred is 4 to 10 parts by weight. When the addition amount of the plasticizer is in the range of 1 to 20 parts by weight with respect to 100 parts by weight of the non-foamed layer constituting resin, a non-foamed layer with no discharge fluctuation during extrusion and no surface bleed-out after extrusion is obtained. .

  The thickness of the extruded foam molded body 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 equivalent thermal conductivity at 20 ° C. of the extruded foam molded body of the present invention is preferably 0.034 W / m · K (0.0292 kcal / m · hr · ° C.) or less, and 0.032 W / m · K (0. 0275 kcal / m · hr · ° C.) or less, more preferably 0.030 W / m · K (0.0258 kcal / m · hr · ° C.) or less.

  The foamed molded product having an equivalent thermal conductivity of 0.034 W / m · K or less is suitably used as a building material application, and contributes to providing a comfortable living space.

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

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

  Evaluation methods for Examples and Comparative Examples are as follows.

(1) Extruded foam molding dimensions [unit: mm]
Thickness: For three foamed molded products sampled at different times, as shown in FIG. 3, the thickness at the central portion (midpoint in the width direction) in the width direction (horizontal direction orthogonal to the extrusion direction) was measured, The average value was calculated.
Width: For three foamed molded products sampled at different times, as shown in FIG. 4, the width at the center in the thickness direction (the middle point in the thickness direction) was measured, and the average value was calculated.
Identification of the central portion in the thickness direction: A portion located at a value of 1/2 of the thickness from the upper surface and a value of 1/2 of the width from the left side was defined as the central portion.

(2) Density of extruded foam molding [unit: kg / m ³ ]
For three extruded foam moldings sampled at different times, the foam density was measured according to the method described in JIS K7222-1999 "Foamed plastics and rubber-Apparent density measurement", and the average value was calculated. did.

(3) Thermal conductivity [unit: W / m · K]
The thermal conductivity of the extruded foamed product was measured using a thermal conductivity measuring device (Eihiro Seiki, HC-074-300). The thermal conductivity when the partial pressure of air in the foam of the extruded foam body is 51 kPa is shown in the examples.

(4) Partial pressure of air in the foam of the extruded foam molded body After the extruded foam molded body was cut out and 10 mm from the surface was removed, the width direction was 25 mm, the length direction was 25 mm, and the thickness direction was from the center in the width direction. It cuts out with the thickness as it is, analyzed and measured the amount of air in an extrusion foaming molding using a gas chromatograph (Shimadzu GC-14A), and calculating an average value. The partial pressure of air was determined.

(5) Average cell diameter in the thickness direction (A)
The central part in the thickness direction was observed at a magnification of 50 times using a microscope [Digital microscope VHX-900 manufactured by Keyence Corporation], and the average cell diameter in the thickness direction ( A) was determined.

Example 1
[Method for producing molten resin containing foaming agent]
Polystyrene [manufactured by PS Japan Co., Ltd., trade name: G9401, MFR = 2.0 g / 10 min] 100 parts by weight, talc [manufactured by Hayashi Kasei Co., Ltd., trade name: TALCAN PAWDER PK-Z] 0.5 weight Parts, calcium stearate [manufactured by Sakai Chemical Industry Co., Ltd., trade name: SC-P] 0.3 parts by weight, liquid paraffin [manufactured by Nippon Oil Corporation, trade name: polybutene LV-50] 0.1 parts by weight. The mixture was dry blended to obtain a styrene resin composition. The styrenic resin composition was supplied at 39.8 kg / hr 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 230 ° C., and a styrenic resin is used as a foaming agent near the tip of the first extruder (the side connected to the second extruder). Styrenic resin composition in which 4.0% by weight of i-butane [manufactured by Mitsui Chemicals Co., Ltd.] and 4.0% by weight of dimethyl ether [manufactured by Taiyo Liquefied Gas Co., Ltd.] are melted with respect to 100% by weight of the resin composition. Press fit into. At this time, the resin pressure at the tip of the first extruder was 10.5 MPa, while the press-fitting pressure of the foaming agent was 12.5 MPa.
In the second extruder connected to the first extruder, the resin temperature is cooled to 127 ° C. and then divided into four, and two types of molten resin containing a foaming agent are provided at the tip of the second extruder. The resin block was supplied to a 7-layer multi-layer feed block [manufactured by Pla Giken Co., Ltd.] at a resin pressure of 8.0 MPa.
[Method for producing molten resin containing no foaming agent]
3. Polystyrene [PS Japan Co., Ltd., trade name: SC004, MFR = 6.5 g / 10 min] 100 parts by weight of dimethyl phthalate [Daihachi Chemical Industry Co., Ltd., trade name: DMP] as a plasticizer 0 parts by weight was added, and extrusion was performed at a resin temperature of 190 ° C. and a discharge amount of 36.2 Kg / hr by a twin screw extruder (manufactured by OE Machinery Co., Ltd .: TEK, 45 mm diameter twin screw extruder), and a master batch was prepared in advance.
The obtained resin was melt-kneaded by heating to 180 ° C. with an extruder having a diameter of 50 mm [manufactured by Pla Giken Co., Ltd.], and a gear pump adjusted to 180 ° C. [manufactured by Kyowa Finetech Co., Ltd .: HDSM-45G- 20 × 1, discharge capacity of 20 cc per rotation], while adjusting the screw speed of the extruder so that the resin pressure becomes 10 MPa. The rotation speed of the gear pump was set to 8 rpm, the flow was divided into three, and the resin pressure was 19.1 MPa and the discharge amount was 10.1 kg / hr to the two-type seven-layer multi-layer feed block.
[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 feed block for the two types of 7-layer multi-layers, the temperature of which is adjusted to 127 ° C., the molten resin (3 layers) containing no foaming agent is divided into four in the thickness direction under a pressure of 6.5 MPa. The molten resin containing the foaming agent thus formed was joined at a thickness of 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm, respectively. .
Multilayer flow doubling device that has the same function as the multi-layer flow described in Japanese Patent Publication No. Sho 54-23025, and is temperature-controlled at 127 ° C. (manufactured by Pla Giken Co., Ltd.) ), Then the combined multi-layer flow is pushed out into the atmosphere from a die lip having a rectangular cross section of 3.0 mm in thickness and 80 mm in width, and temperature-controlled at 100 ° C. It is sandwiched between devices placed and taken up, and has a rectangular parallelepiped shape with a thickness of 24.2 mm and a width of 221 mm, foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam An extruded foam molded article having a 13-layer structure of layer / non-foamed layer / foamed layer / non-foamed layer / foamed layer was obtained.
The density of the extruded foamed product obtained was 42.0 kg / m ³ , the average cell diameter in the thickness direction of the foamed layer was 0.18 mm, and the thermal conductivity at an air partial pressure of 51 kPa was 0.0278 W / m · K. The evaluation results are shown in Table 1.

(Example 2)
[Method for producing molten resin containing foaming agent]
Polystyrene [manufactured by PS Japan Co., Ltd., trade name: G9401, MFR = 2.0 g / 10 min] 100 parts by weight, talc [manufactured by Hayashi Kasei Co., Ltd., trade name: TALCAN PAWDER PK-Z] 0.5 weight Parts, calcium stearate [manufactured by Sakai Chemical Industry Co., Ltd., trade name: SC-P] 0.3 parts by weight, liquid paraffin [manufactured by Nippon Oil Corporation, trade name: polybutene LV-50] 0.1 parts by weight. The mixture was dry blended to obtain a styrene resin composition. The styrenic resin composition was supplied at 39.8 kg / hr 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 230 ° C., and a styrenic resin is used as a foaming agent near the tip of the first extruder (the side connected to the second extruder). Styrenic resin composition in which 4.0% by weight of i-butane [manufactured by Mitsui Chemicals Co., Ltd.] and 4.0% by weight of dimethyl ether [manufactured by Taiyo Liquefied Gas Co., Ltd.] are melted with respect to 100% by weight of the resin composition. Press fit into. At this time, the resin pressure at the tip of the first extruder was 11.0 MPa, while the press-fitting pressure of the foaming agent was 12.7 MPa.
In the second extruder connected to the first extruder, the resin temperature is cooled to 127 ° C. and then divided into four, and two types of molten resin containing a foaming agent are provided at the tip of the second extruder. The resin block was supplied to a 7-layer multi-layer feed block [manufactured by Pla Giken Co., Ltd.] at a resin pressure of 7.8 MPa.
[Method for producing molten resin containing no foaming agent]
3. Polystyrene [PS Japan Co., Ltd., trade name: SC004, MFR = 6.5 g / 10 min] 100 parts by weight of dimethyl phthalate [Daihachi Chemical Industry Co., Ltd., trade name: DMP] as a plasticizer 0 parts by weight was added, and extrusion was performed at a resin temperature of 190 ° C. and a discharge amount of 36.2 Kg / hr by a twin screw extruder (manufactured by OE Machinery Co., Ltd .: TEK, 45 mm diameter twin screw extruder), and a master batch was prepared in advance.
The obtained resin was heated to 165 ° C. with an extruder having a diameter of 50 mm [manufactured by Pla Giken Co., Ltd.], melt kneaded, and the temperature was adjusted to 165 ° C. [manufactured by Kyowa Finetech Co., Ltd .: HDSM-45G-20 X1, discharge capacity of 20 cc per rotation] was supplied while adjusting the screw speed so that the resin pressure was 10 MPa. The number of rotations of the gear pump was 8 rpm, the flow was divided into three, and the resin pressure was 20.7 MPa and the discharge amount was 10.1 kg / hr.
[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 feed block for the two types of 7-layer multi-layer laminated at 127 ° C., the molten resin (3 layers) containing no foaming agent is divided into four in the thickness direction under a pressure of 6.7 MPa. The molten resin containing the foaming agent thus formed was joined at a thickness of 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm, respectively. .
Multilayer flow doubling device that has the same function as the multi-layer flow described in Japanese Patent Publication No. Sho 54-23025, and is temperature-controlled at 127 ° C. (manufactured by Pla Giken Co., Ltd.) ), Then the combined multi-layer flow is pushed out into the atmosphere from a die lip having a rectangular cross section of 3.0 mm in thickness and 80 mm in width, and temperature-controlled at 100 ° C. It is sandwiched between devices placed and taken up, and has a rectangular parallelepiped shape with a thickness of 24.8 mm and a width of 237 mm, foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam An extruded foam molded article having a 13-layer structure of layer / non-foamed layer / foamed layer / non-foamed layer / foamed layer was obtained.
The density of the extruded foamed product obtained was 40.7 kg / m ³ , the average cell diameter in the thickness direction of the foamed layer was 0.17 mm, and the thermal conductivity at an air partial pressure of 51 kPa was 0.0275 W / m · K. The evaluation results are shown in Table 1.

(Example 3)
[Method for producing molten resin containing foaming agent]
Polystyrene [manufactured by PS Japan Co., Ltd., trade name: G9401, MFR = 2.0 g / 10 min] 100 parts by weight, talc [manufactured by Hayashi Kasei Co., Ltd., trade name: TALCAN PAWDER PK-Z] 0.5 weight Parts, calcium stearate [manufactured by Sakai Chemical Industry Co., Ltd., trade name: SC-P] 0.3 parts by weight, liquid paraffin [manufactured by Nippon Oil Corporation, trade name: polybutene LV-50] 0.1 parts by weight. The mixture was dry blended to obtain a styrene resin composition. The styrenic resin composition was supplied at 39.8 kg / hr 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 230 ° C., and a styrenic resin is used as a foaming agent near the tip of the first extruder (the side connected to the second extruder). Styrenic resin composition in which 4.0% by weight of i-butane [manufactured by Mitsui Chemicals Co., Ltd.] and 4.0% by weight of dimethyl ether [manufactured by Taiyo Liquefied Gas Co., Ltd.] are melted with respect to 100% by weight of the resin composition. Press fit into. At this time, the resin pressure at the tip of the first extruder was 11.7 MPa, while the press-fitting pressure of the foaming agent was 13.1 MPa.
In the second extruder connected to the first extruder, the resin temperature is cooled to 127 ° C. and then divided into four, and two types of molten resin containing a foaming agent are provided at the tip of the second extruder. The resin block was supplied to a 7-layer multi-layer feed block [manufactured by Pla Giken Co., Ltd.] at a resin pressure of 8.0 MPa.
[Method for producing molten resin containing no foaming agent]
3. Polystyrene [PS Japan Co., Ltd., trade name: SC004, MFR = 6.5 g / 10 min] 100 parts by weight of dimethyl phthalate [Daihachi Chemical Industry Co., Ltd., trade name: DMP] as a plasticizer 0 parts by weight was added, and extrusion was performed at a resin temperature of 190 ° C. and a discharge amount of 36.2 Kg / hr by a twin screw extruder (manufactured by OE Machinery Co., Ltd .: TEK, 45 mm diameter twin screw extruder), and a master batch was prepared in advance.
The obtained resin was melted and kneaded by heating to 150 ° C. with a 50 mm diameter extruder (Pura Giken Co., Ltd.) and the temperature was adjusted to 150 ° C. [manufactured by Kyowa Finetech Co., Ltd .: HDSM-45G-20 X1, discharge capacity of 20 cc per rotation] was supplied while adjusting the screw speed so that the resin pressure was 10 MPa. The rotation speed of the gear pump was set to 8 rpm, the flow was divided into three, and the resin pressure was 24.2 MPa and the discharge amount was 10.1 kg / hr to the feed block for the two kinds of 7-layer multilayer lamination.
[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 feed block for the two types of 7-layer multi-layers, the temperature of which is adjusted to 127 ° C., the molten resin (3 layers) containing no foaming agent is flowed in four directions in the thickness direction under a pressure of 7.3 MPa. The molten resin containing the foaming agent was joined to each other at a thickness of 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm.
Multilayer flow doubling device that has the same function as the multi-layer flow described in Japanese Patent Publication No. Sho 54-23025, and is temperature-controlled at 127 ° C. (manufactured by Pla Giken Co., Ltd.) ), Then the combined multi-layer flow is pushed out into the atmosphere from a die lip having a rectangular cross section of 3.0 mm in thickness and 80 mm in width, and temperature-controlled at 100 ° C. It is sandwiched between devices placed and taken up, and has a rectangular parallelepiped shape with a thickness of 24.7 mm and a width of 222 mm, foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam An extruded foam molded article having a 13-layer structure of layer / non-foamed layer / foamed layer / non-foamed layer / foamed layer was obtained.
The density of the extruded foamed product obtained was 43.0 kg / m ³ , the average cell diameter in the thickness direction of the foamed layer was 0.13 mm, and the thermal conductivity at an air partial pressure of 51 kPa was 0.0269 W / m · K. The evaluation results are shown in Table 1.

Example 4
[Method for producing molten resin containing foaming agent]
Polystyrene [manufactured by PS Japan Co., Ltd., trade name: G9401, MFR = 2.0 g / 10 min] 100 parts by weight, talc [manufactured by Hayashi Kasei Co., Ltd., trade name: TALCAN PAWDER PK-Z] 0.5 weight Parts, calcium stearate [manufactured by Sakai Chemical Industry Co., Ltd., trade name: SC-P] 0.3 parts by weight, liquid paraffin [manufactured by Nippon Oil Corporation, trade name: polybutene LV-50] 0.1 parts by weight. The mixture was dry blended to obtain a styrene resin composition. The styrenic resin composition was supplied at 39.8 kg / hr 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 230 ° C., and a styrenic resin is used as a foaming agent near the tip of the first extruder (the side connected to the second extruder). Styrenic resin composition in which 4.0% by weight of i-butane [manufactured by Mitsui Chemicals Co., Ltd.] and 4.0% by weight of dimethyl ether [manufactured by Taiyo Liquefied Gas Co., Ltd.] are melted with respect to 100% by weight of the resin composition. Press fit into. At this time, the resin pressure at the tip of the first extruder was 11.5 MPa, while the press-fitting pressure of the foaming agent was 12.7 MPa.
In the second extruder connected to the first extruder, the resin temperature is cooled to 127 ° C. and then divided into four, and two types of molten resin containing a foaming agent are provided at the tip of the second extruder. The resin block was supplied to a 7-layer multi-layer feed block [manufactured by Pla Giken Co., Ltd.] at a resin pressure of 7.8 MPa.
[Method for producing molten resin containing no foaming agent]
3. Polystyrene [PS Japan Co., Ltd., trade name: SC004, MFR = 6.5 g / 10 min] 100 parts by weight of dimethyl phthalate [Daihachi Chemical Industry Co., Ltd., trade name: DMP] as a plasticizer 0 parts by weight was added, and extrusion was performed at a resin temperature of 190 ° C. and a discharge amount of 36.2 Kg / hr by a twin screw extruder (manufactured by OE Machinery Co., Ltd .: TEK, 45 mm diameter twin screw extruder), and a master batch was prepared in advance.
The obtained resin was heated to 150 ° C. with an extruder having a diameter of 50 mm [manufactured by Pla Giken Co., Ltd.], melt kneaded, and temperature-controlled at 150 ° C. [manufactured by Kyowa Finetech Co., Ltd .: HDSM-45G-20] X1, discharge capacity of 20 cc per rotation] was supplied while adjusting the screw speed so that the resin pressure was 10 MPa. The rotation speed of the gear pump was 4 rpm, the flow was divided into three, and the resin pressure was 21.4 MPa and the discharge amount was 5.0 kg / hr.
[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 feed block for the two types of 7-layer multi-layers, the temperature of which is adjusted to 127 ° C., the molten resin (3 layers) containing no foaming agent is flowed in four directions in the thickness direction under a pressure of 7.0 MPa. The molten resin containing the foaming agent was joined to each other at a thickness of 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm.
Multilayer flow doubling device that has the same function as the multi-layer flow described in Japanese Patent Publication No. Sho 54-23025, and is temperature-controlled at 127 ° C. [manufactured by Pla Giken Co., Ltd.] , And a belt conveyer up and down by extruding the merged multilayer flow into the atmosphere from a die lip having a rectangular cross section of 3.0 mm in thickness and 80 mm in width and temperature-controlled at 100 ° C. It is sandwiched between devices placed and taken up, and has a rectangular parallelepiped shape with a thickness of 24.7 mm and a width of 216 mm, foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam An extruded foam molded article having a 13-layer structure of layer / non-foamed layer / foamed layer / non-foamed layer / foamed layer was obtained.
The density of the extruded foamed product obtained was 39.3 kg / m ³ , the average cell diameter in the thickness direction of the foamed layer was 0.15 mm, and the thermal conductivity at an air partial pressure of 51 kPa was 0.0277 W / m · K. The evaluation results are shown in Table 1.

(Example 5)
[Method for producing molten resin containing foaming agent]
Polystyrene [manufactured by PS Japan Co., Ltd., trade name: G9401, MFR = 2.0 g / 10 min] 100 parts by weight, talc [manufactured by Hayashi Kasei Co., Ltd., trade name: TALCAN PAWDER PK-Z] 0.5 weight Parts, calcium stearate [manufactured by Sakai Chemical Industry Co., Ltd., trade name: SC-P] 0.3 parts by weight, liquid paraffin [manufactured by Nippon Oil Corporation, trade name: polybutene LV-50] 0.1 parts by weight. The mixture was dry blended to obtain a styrene resin composition. The styrenic resin composition was supplied at 39.8 kg / hr 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 230 ° C., and a styrenic resin is used as a foaming agent near the tip of the first extruder (the side connected to the second extruder). Styrenic resin composition in which 4.0% by weight of i-butane [manufactured by Mitsui Chemicals Co., Ltd.] and 4.0% by weight of dimethyl ether [manufactured by Taiyo Liquefied Gas Co., Ltd.] are melted with respect to 100% by weight of the resin composition. Press fit into. At this time, the resin pressure at the tip of the first extruder was 11.8 MPa, while the press-fitting pressure of the foaming agent was 13.2 MPa.
In the second extruder connected to the first extruder, the resin temperature is cooled to 127 ° C. and then divided into four, and two types of molten resin containing a foaming agent are provided at the tip of the second extruder. The resin block was supplied to a 7-layer multi-layer feed block [manufactured by Pla Giken Co., Ltd.] at a resin pressure of 8.5 MPa.
[Method for producing molten resin containing no foaming agent]
3. Polystyrene [PS Japan Co., Ltd., trade name: SC004, MFR = 6.5 g / 10 min] 100 parts by weight of dimethyl phthalate [Daihachi Chemical Industry Co., Ltd., trade name: DMP] as a plasticizer 0 parts by weight was added, and extrusion was performed at a resin temperature of 190 ° C. and a discharge amount of 36.2 Kg / hr by a twin screw extruder (manufactured by OE Machinery Co., Ltd .: TEK, 45 mm diameter twin screw extruder), and a master batch was prepared in advance.
The obtained resin was melt-kneaded by heating to 150 ° C. with an extruder having a diameter of 50 mm [manufactured by Pla Giken Co., Ltd.], and a gear pump adjusted to 150 ° C. [manufactured by Kyowa Finetech Co., Ltd .: HDSM-45G- 20 × 1, discharge capacity of 20 cc per rotation], and the resin pressure was supplied while adjusting the screw rotation speed so as to be 10 MPa. The rotation speed of the gear pump was set to 12 rpm, the flow was divided into three, and the two types of 7-layer multi-layer feed blocks were supplied at a resin pressure of 25.1 MPa and a discharge amount of 15.1 Kg / hr.
[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 feed block for the two types of 7-layer multi-layers, the temperature of which is adjusted to 127 ° C., four molten resins (three layers) containing no blowing agent are flown in the thickness direction under a pressure of 7.5 MPa. The molten resin containing the foaming agent was joined to each other at a thickness of 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm.
Multilayer flow doubling device that has the same function as the multi-layer flow described in Japanese Patent Publication No. Sho 54-23025, and is temperature-controlled at 127 ° C. (manufactured by Pla Giken Co., Ltd.) ), Then the combined multi-layer flow is pushed out into the atmosphere from a die lip having a rectangular cross section of 3.0 mm in thickness and 80 mm in width, and temperature-controlled at 100 ° C. It is sandwiched between devices placed and taken up, and is a rectangular parallelepiped with a thickness of 24.5 mm and a width of 230 mm, foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam An extruded foam molded article having a 13-layer structure of layer / non-foamed layer / foamed layer / non-foamed layer / foamed layer was obtained.
The density of the extruded foamed product obtained was 47.0 kg / m ³ , the average cell diameter in the thickness direction of the foamed layer was 0.13 mm, and the thermal conductivity at an air partial pressure of 51 kPa was 0.0273 W / m · K. The evaluation results are shown in Table 1.

(Example 6)
[Method for producing molten resin containing foaming agent]
Polystyrene [manufactured by PS Japan Co., Ltd., trade name: 680, MFR = 7.0 g / 10 min] 100 parts by weight, talc [manufactured by Hayashi Kasei Co., Ltd., trade name: TALCAN PAWDER PK-Z] 0.5 weight Parts, calcium stearate [manufactured by Sakai Chemical Industry Co., Ltd., trade name: SC-P] 0.3 parts by weight, liquid paraffin [manufactured by Nippon Oil Corporation, trade name: polybutene LV-50] 0.1 parts by weight. The mixture was dry blended to obtain a styrene resin composition. The styrenic resin composition was supplied at 41.1 kg / hr 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 230 ° C., and a styrenic resin is used as a foaming agent near the tip of the first extruder (the side connected to the second extruder). A molten styrene-based resin composition containing 6.0% by weight of i-butane [manufactured by Mitsui Chemicals Co., Ltd.] and 2.0% by weight of dimethyl ether [manufactured by Taiyo Liquefaction Gas Co., Ltd.] with respect to 100% by weight of the resin composition. Press fit into. At this time, the resin pressure at the tip of the first extruder was 11.0 MPa, while the press-fitting pressure of the foaming agent was 12.3 MPa.
In the second extruder connected to the first extruder, the resin temperature is cooled to 115 ° C., and then divided into four, and two types of molten resin containing a foaming agent are provided at the tip of the second extruder. The resin block was supplied to a 7-layer multilayer feed block [manufactured by Pla Giken Co., Ltd.] at a resin pressure of 6.8 MPa.
[Method for producing molten resin containing no foaming agent]
5. Polystyrene [manufactured by PS Japan Co., Ltd., trade name: 679, MFR = 18.0 g / 10 min], 100 parts by weight of dimethyl phthalate [manufactured by Daihachi Chemical Industry Co., Ltd., trade name: DMP] 0 parts by weight was added, and extrusion was performed at a resin temperature of 190 ° C. and a discharge amount of 27.9 Kg / hr by a twin screw extruder (manufactured by OE Machinery Co., Ltd .: TEK, 45 mm diameter twin screw extruder), and a master batch was prepared in advance.
The obtained resin was heated to 150 ° C. with an extruder having a diameter of 50 mm [manufactured by Pla Giken Co., Ltd.], melt kneaded, and temperature-controlled at 150 ° C. [manufactured by Kyowa Finetech Co., Ltd .: HDSM-45G-20] X1, discharge capacity of 20 cc per rotation] was supplied while adjusting the screw speed so that the resin pressure was 10 MPa. The rotation speed of the gear pump was set to 8 rpm, the flow was divided into three, and the resin pressure was 19.1 MPa and the discharge amount was 10.1 kg / hr to the two-type seven-layer multi-layer feed block.
[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 feed block for the two types of 7-layer multi-layers, the temperature of which is adjusted to 115 ° C., the molten resin (3 layers) containing no foaming agent is flowed in four directions in the thickness direction under a pressure of 6.0 MPa. The molten resin containing the foaming agent was joined to each other at a thickness of 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm.
Multilayer flow doubling device that has the same function as the multi-layer flow described in Japanese Patent Publication No. Sho 54-23025, and is temperature-controlled at 127 ° C. (manufactured by Pla Giken Co., Ltd.) ), A multilayered flow having a rectangular cross section of 2.6 mm in thickness direction and 80 mm in width direction is extruded into the atmosphere from a die lip temperature-controlled at 90 ° C. It is sandwiched between devices placed and taken up, and has a rectangular parallelepiped shape with a thickness of 22.6 mm and a width of 225 mm, foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam An extruded foam molded article having a 13-layer structure of layer / non-foamed layer / foamed layer / non-foamed layer / foamed layer was obtained.
The density of the extruded foamed product obtained was 46.1 kg / m ³ , the average cell diameter in the thickness direction of the foamed layer was 0.20 mm, and the thermal conductivity at an air partial pressure of 51 kPa was 0.0281 W / m · K. The evaluation results are shown in Table 1.

(Example 7)
[Method for producing molten resin containing foaming agent]
Polystyrene [manufactured by PS Japan Co., Ltd., trade name: 680, MFR = 7.0 g / 10 min] 100 parts by weight, talc [manufactured by Hayashi Kasei Co., Ltd., trade name: TALCAN PAWDER PK-Z] 0.5 weight Parts, calcium stearate [manufactured by Sakai Chemical Industry Co., Ltd., trade name: SC-P] 0.3 parts by weight, liquid paraffin [manufactured by Nippon Oil Corporation, trade name: polybutene LV-50] 0.1 parts by weight. The mixture was dry blended to obtain a styrene resin composition. The styrenic resin composition was supplied at 41.1 kg / hr 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 230 ° C., and a styrenic resin is used as a foaming agent near the tip of the first extruder (the side connected to the second extruder). A molten styrene-based resin composition containing 6.0% by weight of i-butane [manufactured by Mitsui Chemicals Co., Ltd.] and 2.0% by weight of dimethyl ether [manufactured by Taiyo Liquefaction Gas Co., Ltd.] with respect to 100% by weight of the resin composition. Press fit into. At this time, the resin pressure at the tip of the first extruder was 11.5 MPa, while the press-fitting pressure of the foaming agent was 13.0 MPa.
In the second extruder connected to the first extruder, the resin temperature is cooled to 115 ° C., and then divided into four, and two types of molten resin containing a foaming agent are provided at the tip of the second extruder. The resin block was supplied to a 7-layer multi-layer feed block [manufactured by Pla Giken Co., Ltd.] at a resin pressure of 7.6 MPa.
[Method for producing molten resin containing no foaming agent]
3. Polystyrene [manufactured by PS Japan Co., Ltd., trade name: 679, MFR = 18.0 g / 10 min], 100 parts by weight of dimethyl phthalate as plasticizer [manufactured by Daihachi Chemical Industry Co., Ltd., trade name: DMP] 0 parts by weight was added, and extrusion was performed at a resin temperature of 190 ° C. and a discharge amount of 36.2 Kg / hr by a twin screw extruder (manufactured by OE Machinery Co., Ltd .: TEK, 45 mm diameter twin screw extruder), and a master batch was prepared in advance.
The obtained resin was melt-kneaded by heating to 150 ° C. with an extruder having a diameter of 50 mm [manufactured by Pla Giken Co., Ltd.], and a gear pump adjusted to 150 ° C. [manufactured by Kyowa Finetech Co., Ltd .: HDSM-45G- 20 × 1, discharge capacity of 20 cc per rotation], and the resin pressure was supplied while adjusting the screw rotation speed so as to be 10 MPa. The rotation speed of the gear pump was set to 8 rpm, the flow was divided into three, and the resin pressure was 26.3 MPa and the discharge amount was 10.1 kg / hr to the above-mentioned feed block for the two kinds of 7-layer multilayer.
[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 feed block for the two kinds of 7-layer multi-layers, the temperature of which is adjusted to 115 ° C., four molten resins (three layers) containing no blowing agent are flowed in the thickness direction under a pressure of 7.0 MPa. The molten resin containing the foaming agent was joined to each other at a thickness of 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm.
Multilayer flow doubling device that has the same function as the multi-layer flow described in Japanese Patent Publication No. Sho 54-23025, and is temperature-controlled at 127 ° C. [manufactured by Pla Giken Co., Ltd.] , And a belt conveyer up and down by extruding the merged multilayer flow into the atmosphere from a die lip having a rectangular cross section of 2.6 mm in thickness and 80 mm in width and temperature-controlled at 90 ° C. Is sandwiched between and placed in a device having a thickness of 21.9 mm and a width of 220 mm, foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam An extruded foam molded article having a 13-layer structure of layer / non-foamed layer / foamed layer / non-foamed layer / foamed layer was obtained.
The density of the extruded foamed product obtained was 46.3 kg / m ³ , the average cell diameter in the thickness direction of the foamed layer was 0.11 mm, and the thermal conductivity at an air partial pressure of 51 kPa was 0.0263 W / m · K. The evaluation results are shown in Table 1.

(Comparative Example 1)
[Method for producing molten resin containing foaming agent]
Polystyrene [manufactured by PS Japan Co., Ltd., trade name: G9401, MFR = 2.0 g / 10 min] 100 parts by weight, talc [manufactured by Hayashi Kasei Co., Ltd., trade name: TALCAN PAWDER PK-Z] 0.5 weight Parts, calcium stearate [manufactured by Sakai Chemical Industry Co., Ltd., trade name: SC-P] 0.3 parts by weight, liquid paraffin [manufactured by Nippon Oil Corporation, trade name: polybutene LV-50] 0.1 parts by weight. The mixture was dry blended to obtain a styrene resin composition. The styrenic resin composition was supplied at 39.8 kg / hr 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 230 ° C., and a styrenic resin is used as a foaming agent near the tip of the first extruder (the side connected to the second extruder). Styrenic resin composition in which 4.0% by weight of i-butane [manufactured by Mitsui Chemicals Co., Ltd.] and 4.0% by weight of dimethyl ether [manufactured by Taiyo Liquefied Gas Co., Ltd.] are melted with respect to 100% by weight of the resin composition. Press fit into. At this time, the resin pressure at the tip of the first extruder was 9.8 MPa, while the press-fitting pressure of the foaming agent was 11.6 MPa.
In the second extruder connected to the first extruder, the resin temperature is cooled to 127 ° C. and then divided into four, and two types of molten resin containing a foaming agent are provided at the tip of the second extruder. The resin block was supplied to a 7-layer multilayer feed block [manufactured by Pla Giken Co., Ltd.] at a resin pressure of 6.8 MPa.
[Method for Producing Extrusion Foam Molded Product from Molten Resin Containing Foaming Agent]
In the feed block for the two kinds of 7-layer multi-layers, the temperature of which is adjusted to 127 ° C., the molten resin containing the foaming agent under the pressure of 6.0 MPa is respectively 5.2 mm / 5.2 mm / 5. They were merged at a thickness of 2 mm / 5.2 mm.
Stacking doubling device having a function similar to that of splitting and stacking the multi-layered flow described in Japanese Patent Publication No. Sho 54-23025 and temperature-controlled at 127 ° C. [Pura Giken Co., Ltd. , And a belt conveyer up and down by extruding the merged multilayer flow into the atmosphere from a die lip having a rectangular cross section of 3.0 mm in thickness and 80 mm in width and temperature-controlled at 100 ° C. Was sandwiched and taken up, and a rectangular parallelepiped extruded foam molded body having a thickness of 24.2 mm and a width of 222 mm was obtained.
The density of the obtained extrusion foamed molded product was 35.5 kg / m ³ , the average cell diameter in the thickness direction of the foamed layer was 0.28 mm, and the thermal conductivity at an air partial pressure of 51 kPa was 0.0290 W / m · K. The evaluation results are shown in Table 1.

(Comparative Example 2)
[Method for producing molten resin containing foaming agent]
Polystyrene [manufactured by PS Japan Co., Ltd., trade name: G9401, MFR = 2.0 g / 10 min] 100 parts by weight, talc [manufactured by Hayashi Kasei Co., Ltd., trade name: TALCAN PAWDER PK-Z] 0.5 weight Parts, calcium stearate [manufactured by Sakai Chemical Industry Co., Ltd., trade name: SC-P] 0.3 parts by weight, liquid paraffin [manufactured by Nippon Oil Corporation, trade name: polybutene LV-50] 0.1 parts by weight. The mixture was dry blended to obtain a styrene resin composition. The styrenic resin composition was supplied at 39.8 kg / hr 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 230 ° C., and a styrenic resin is used as a foaming agent near the tip of the first extruder (the side connected to the second extruder). Styrenic resin composition in which 4.0% by weight of i-butane [manufactured by Mitsui Chemicals Co., Ltd.] and 4.0% by weight of dimethyl ether [manufactured by Taiyo Liquefied Gas Co., Ltd.] are melted with respect to 100% by weight of the resin composition. Press fit into. At this time, the resin pressure at the tip of the first extruder was 10.7 MPa, while the press-fitting pressure of the foaming agent was 12.1 MPa.
In the second extruder connected to the first extruder, the resin temperature is cooled to 127 ° C. and then divided into four, and two types of molten resin containing a foaming agent are provided at the tip of the second extruder. A 7-layer multi-layer feed block [manufactured by Pla Giken Co., Ltd.] was supplied at a resin pressure of 7.5 MPa.
[Method for producing molten resin containing no foaming agent]
3. Polystyrene [PS Japan Co., Ltd., trade name: SC004, MFR = 6.5 g / 10 min] 100 parts by weight of dimethyl phthalate [Daihachi Chemical Industry Co., Ltd., trade name: DMP] as a plasticizer 0 parts by weight was added, and extrusion was performed at a resin temperature of 190 ° C. and a discharge amount of 36.2 Kg / hr by a twin screw extruder (manufactured by OE Machinery Co., Ltd .: TEK, 45 mm diameter twin screw extruder), and a master batch was prepared in advance.
The obtained resin was heated to 150 ° C. with an extruder having a diameter of 50 mm (manufactured by Pla Giken Co., Ltd.), melt kneaded, and the screw rotation speed was adjusted to 20.0 rpm so that the discharge amount was 10.0 kg / hr. It was divided into two and supplied to the feed block for the two types 7-layer multilayer lamination at a resin pressure of 17.8 MPa.
[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 feed block for the two types of 7-layer multi-layers, the temperature of which is adjusted to 127 ° C., four layers of molten resin (three layers) containing no blowing agent are flown in the thickness direction under a pressure of 6.5 MPa. The molten resin containing the foaming agent was joined to each other at a thickness of 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm / 1.4 mm / 5.2 mm.
Multilayer flow doubling device that has the same function as the multi-layer flow described in Japanese Patent Publication No. Sho 54-23025, and is temperature-controlled at 127 ° C. (manufactured by Pla Giken Co., Ltd.) ), Then the combined multi-layer flow is pushed out into the atmosphere from a die lip having a rectangular cross section of 3.0 mm in thickness and 80 mm in width, and temperature-controlled at 100 ° C. It is sandwiched between devices placed and taken up, and has a rectangular parallelepiped shape with a thickness of 24.2 mm and a width of 212 mm, foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam layer / non-foam layer / foam An extruded foam molded article having a 13-layer structure of layer / non-foamed layer / foamed layer / non-foamed layer / foamed layer was obtained.
The density of the extruded foamed product obtained was 42.0 kg / m ³ , the average cell diameter in the thickness direction of the foamed layer was 0.26 mm, and the thermal conductivity at an air partial pressure of 51 kPa was 0.0285 W / m · K. The evaluation results are shown in Table 1.

(Comparative Example 3)
[Method for producing molten resin containing foaming agent]
Polystyrene [manufactured by PS Japan Co., Ltd., trade name: 680, MFR = 7.0 g / 10 min] 100 parts by weight, talc [manufactured by Hayashi Kasei Co., Ltd., trade name: TALCAN PAWDER PK-Z] 0.5 weight Parts, calcium stearate [manufactured by Sakai Chemical Industry Co., Ltd., trade name: SC-P] 0.3 parts by weight, liquid paraffin [manufactured by Nippon Oil Corporation, trade name: polybutene LV-50] 0.1 parts by weight. The mixture was dry blended to obtain a styrene resin composition. The styrenic resin composition was supplied at 41.1 kg / hr 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 230 ° C., and a styrenic resin is used as a foaming agent near the tip of the first extruder (the side connected to the second extruder). A molten styrene-based resin composition containing 6.0% by weight of i-butane [manufactured by Mitsui Chemicals Co., Ltd.] and 2.0% by weight of dimethyl ether [manufactured by Taiyo Liquefaction Gas Co., Ltd.] with respect to 100% by weight of the resin composition. Press fit into. At this time, the resin pressure at the tip of the first extruder was 10.0 MPa, while the press-fitting pressure of the foaming agent was 11.4 MPa.
In the second extruder connected to the first extruder, the resin temperature is cooled to 115 ° C., and then divided into four, and two types of molten resin containing a foaming agent are provided at the tip of the second extruder. The resin block was supplied to a feed block for 7-layer multilayer lamination [manufactured by Pla Giken Co., Ltd.] at a resin pressure of 5.5 MPa.
[Method for Producing Extrusion Foam Molded Product from Molten Resin Containing Foaming Agent]
In the feed block for the two types 7-layer multi-layer laminated at 115 ° C., the melted resin containing the foaming agent in the thickness direction under a pressure of 4.9 MPa was 5.2 mm / 5. It merged with the thickness of 2 mm / 5.2 mm / 5.2 mm.
Multilayer flow doubling device that has the same function as the multi-layer flow described in Japanese Patent Publication No. Sho 54-23025, and is temperature-controlled at 127 ° C. (manufactured by Pla Giken Co., Ltd.) ), A multilayered flow having a rectangular cross section of 2.6 mm in thickness direction and 80 mm in width direction is extruded into the atmosphere from a die lip temperature-controlled at 90 ° C. Was sandwiched and taken up, and a rectangular parallelepiped extruded foam molded body having a thickness of 24.3 mm and a width of 290 mm was obtained.
The density of the obtained extruded foam molded body was 41.9 kg / m ³ , the average cell diameter in the thickness direction of the foamed layer was 0.30 mm, and the thermal conductivity at an air partial pressure of 51 kPa was 0.0293 W / m · K. The evaluation results are shown in Table 1.

表１の実施例１〜５と比較例１、２との対比、実施例６〜７と比較例３との対比により、厚み方向に発泡層が非発泡層を介して積層されてなる構造を有すると共に、ギヤポンプから供給される発泡剤を含有しない溶融樹脂の樹脂圧力を調整することで発泡層の厚み方向平均気泡径を０．１０〜０．２５ｍｍとした発泡体（実施例）は、発泡層１層の成形体（比較例１、３）やギヤポンプを介さずに発泡剤を含有しない溶融樹脂を多層積層装置に供給して得られる成形体(比較例２）に対して、断熱性に優れた発泡成形体が得られることが確認された。

According to the comparison between Examples 1 to 5 and Comparative Examples 1 and 2 in Table 1 and the comparison between Examples 6 to 7 and Comparative Example 3, a structure in which a foam layer is laminated via a non-foam layer in the thickness direction. A foam (Example) having an average cell diameter in the thickness direction of the foam layer of 0.10 to 0.25 mm by adjusting the resin pressure of the molten resin that does not contain the foaming agent supplied from the gear pump. Compared to the molded body (Comparative Example 2) obtained by supplying a multilayered laminating apparatus with a molten resin not containing a foaming agent without using a gear pump (Comparative Examples 1 and 3) and a gear pump. It was confirmed that an excellent foamed molded product was obtained.

1. 1. Foaming extruder 2. Non-foaming extruder 3. Gear pump 4. Laminating apparatus Stacking doubler 6. 6. Molding die Molding machine 8. Multi-layer laminating apparatus9. Multilayer foaming device 10. Foam layer 11. Non-foamed layer 12. 12. Thickness measurement position of extruded foam molding Width measurement position multilayer of extruded foam

Claims (8)

At least one molten resin containing a blowing agent; and
A laminated molten resin obtained by joining at least one molten resin containing no foaming agent, which has been pressurized by a gear pump, in a vertical direction that is a thickness direction under high pressure,
It is an extrusion foam molded article obtained by opening it under atmospheric pressure while extruding it in the flow direction, adjusting it to a fixed cross-sectional shape with a mold and continuously molding it,
The extruded foam molding has a structure in which a foam layer is laminated via a non-foam layer in the thickness direction, and the foam layer is composed of bubbles having an average cell diameter in the thickness direction of 0.25 mm or less. Extruded foamed product characterized by the above. The extruded foam molded article according to claim 1, wherein the density of the extruded foam molded article is 20 to 65 kg / m ³ . The extrusion foamed molded product according to claim 1 or 2, wherein the density of the extruded foamed molded product is 20 to 40 kg / m ³ .   The extruded foam molded article according to any one of claims 1 to 3, wherein an average cell diameter in the thickness direction of the foamed layer is 0.10 to 0.25 mm.   5. The extruded foam according to claim 1, wherein the extruded foamed molded article has a plurality of the structures in which a foamed layer is laminated via a non-foamed layer in the thickness direction. Molded body.   The resin constituting the foam layer is one or more resins selected from the group consisting of polystyrene, styrene-acrylonitrile copolymer, styrene-acrylic acid copolymer, and modified polyphenylene ether resin. The extruded foam molded article according to any one of claims 1 to 5.   The extruded foam molded article according to claim 6, wherein the resin constituting the foamed layer is polystyrene. The one or more types of hydrocarbons chosen from propane, normal butane, isobutane, and cyclopentane are contained in the bubble which comprises the said foaming layer, The any one of Claims 1-7 characterized by the above-mentioned. Extruded foamed body.

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