JP5745289B2 - Styrene resin extruded foam laminate and method for producing the same - Google Patents

Description

  The present invention relates to a styrene-based resin foam laminate that is excellent in lightness, strength, and recyclability.

  Conventionally, a styrene resin is heated and melted with an extruder, etc., and then a foaming agent is added and melt-kneaded resin composition or a thermally decomposable foaming agent is added to a styrene resin and heated and melted and kneaded with an extruder. A method for continuously producing a foam by extruding the obtained resin composition through a mold into a low pressure region is already known (see Patent Documents 1 and 2).

  Styrenic resin foams are used in various applications such as heat insulating materials and core materials. However, there was no high-strength material that could replace the wood-based material used as a structural member.

  On the other hand, in recent years, various foam products used as substitutes for wooden members have been put on the market.

However, in order to obtain physical properties such as the strength required for the materials in which wood-based materials are used, the magnification of the foam is reduced to 1.5-2 times, or wood-based powders and fillers are added. Measures are being taken. Therefore, since it becomes a density comparable as compared with a wood type member, the characteristic of lightweight property cannot be provided. In addition, when wood-based powder is added, the recyclability is low, and the end materials discharged in the manufacturing process and the used members can only be used for thermal recycling.
In addition, in foams with a low foaming ratio of 1.5 to 2 times, cracking and chipping are likely to occur in the process of fixing with wood screws and the like, and an impact resistance improver is added to solve the drawbacks. May be. For this reason, cost increases and recyclability may be impaired.

On the other hand, a foam with a foaming ratio of 3 times or more is a cell structure, so that it can be used as a substitute for a wood-based member, such as physical defects such as soft nails and brittleness, and fine irregularities on the surface. There are appearance defects.
For this reason, when foaming with a foaming ratio of 3 times or more is applied, such as hitting with a nail or fastening with a wood screw, or if it hits the object, it may crack, crack, or be greatly dented. is there.

In order to compensate for these defects, measures have been taken to obtain a foam laminate obtained by laminating a non-foam layer on the surface of the foam layer.
However, even when a non-foamed layer is formed on the surface of the foamed layer, when a local load is applied, the desired strength may not be obtained due to the damage of the foamed layer immediately below the non-foamed layer. In order to improve, measures such as increasing the thickness of the non-foamed layer may be taken. However, in that case, the problem of being inferior in lightness occurs.
Moreover, although the method of making thin using resin with high hardness as a non-foamed layer is also mentioned, the problem which cannot ensure recyclability arises in that case.

  Under the circumstances as described above, there is a demand for a member that changes to a wood-based material that is made of a synthetic resin that is lightweight, excellent in strength, workability, and recyclability.

Japanese Patent Publication No.31-5393 Japanese Patent Publication No.42-19195

  The present invention was made to solve the above-mentioned problems of the styrene resin extruded laminate foam, and provides a styrene resin extruded foam laminate that is excellent in lightness, strength, and workability. With the goal.

  As a result of diligent research to solve the above-mentioned problems, the inventor made the thickness of the non-foamed layer formed on the surface of the foamed laminate a specific range, the expansion ratio directly below the non-foamed layer, and the entire laminate. It has been found that by setting the expansion ratio of the foam to a specific range, a foam having lightness, excellent compressive strength, and excellent workability with nails, wood screws and the like can be obtained.

That is, this invention consists of the following structures.
[1] A non-foamed layer having a thickness of 0.015 to 0.7 mm is formed on at least one surface of a styrenic resin foamed layer obtained by heating and melting a styrenic resin, adding a foaming agent, and extruding and foaming the foaming agent. A styrene foam laminate,
The expansion ratio at 1 mm immediately below the non-foamed layer is 1.5 to 4 times,
The present invention relates to a styrene-based foam laminate, characterized in that the expansion ratio of the entire foam laminate including a non-foam layer is 3 to 10 times.
[2] The styrene-based resin extruded foam laminate according to [1] above, wherein the surface hardness is 400N to 1000N.
[3] The styrene-based resin extruded foam laminate according to [1] or [2], wherein the foamed layer has a closed cell ratio of 75% or more.
[4] A method for producing a foam laminate including a styrene resin foam layer obtained by heating and melting a styrene resin, adding a foaming agent, and extruding and foaming the foaming agent. A non-foamed layer of 015 to 0.7 mm is formed, the foaming magnification in the 1 mm immediately below the non-foamed layer of the foamed layer is 1.5 to 4 times, and the magnification of the entire foamed laminate is 3 to 10 times The present invention relates to a method for producing a styrenic foam.

  The styrenic foam laminate of the present invention can be produced with a styrene resin extruded foam laminate having lightness, excellent compressive strength, and excellent workability with nails, wood screws and the like. The styrene resin foam laminate of the present invention is useful for various applications such as automobile members, building members, housing equipment members, packaging members, and the like due to its excellent performance.

FIG. 1 is an enlarged photograph of a cross section in the thickness direction of the styrene-based foam laminate of the present invention, and is an enlarged photograph when the non-foamed layer includes a fine foamed layer. FIG. 2 is a schematic view of a molding die used for producing the styrene-based foam laminate of the present invention. FIG. 3 is a schematic view of a molding process by a roll method used for producing a conventional styrene foam laminate. A foamable styrenic resin composition adjusted to a resin temperature suitable for foaming in an extruder is extruded into the atmosphere from an extrusion die 7 (for example, a T-die), and the surface is rubbed with a molding fixing roll 8 to obtain a surface layer. The bubbles are then crushed and then cooled and solidified by the cooling free roll 9, and then taken by the take-up drive roll 6 at a constant speed and then cut to obtain the styrene-based resin foam laminate 10.

  The styrene foam laminate of the present invention has a thickness of 0.015 to 0.00 on at least one side of a styrene resin foam layer obtained by heating and melting a styrene resin, adding a foaming agent, and extruding the styrene resin. A styrene-based foam laminate having a 7 mm non-foamed layer formed, the foaming ratio at 1 mm immediately below the non-foamed layer being 1.5 to 4 times, and foaming of the entire foamed laminate including the non-foamed layer The present invention relates to a styrene-based foam laminate, wherein the magnification is 3 to 10 times.

  In the styrenic foam laminate of the present invention, by controlling the thickness of the non-foamed layer, it is possible to prevent cracks and cracks caused by biting of the head of the nail when the nail is struck.

The thickness of the non-foamed layer in the present invention is preferably 0.015 to 0.7 mm, more preferably 0.02 to 0.6 mm, and particularly preferably 0.1 to 0.6 mm.
When the thickness of the non-foamed layer is smaller than 0.015 mm, a crack may occur in the biting portion of the head of the nail of the non-foamed layer when the nail is driven. When the thickness of the non-foamed layer is larger than 0.7 mm, the non-foamed layer may be cracked or inferior in weight when the nail is struck.

The non-foamed layer in the present invention represents a non-foamed layer and a fine foamed layer. The fine foam layer represents a layer having a foaming ratio of 1.0 to 1.3 times.
Here, the thickness of the non-foamed layer is a value determined as follows.
From the obtained foamed laminate, the vertical direction was cut along a line connecting the midpoints in the width direction with respect to each sample obtained by cutting five samples of length 30 mm × width 30 mm at equal intervals in the width direction. An enlarged photograph of the cut surface (thickness direction) is taken with a microscope. As shown in FIG. 1, in the obtained photograph (magnification: 200 times), a region where no bubbles exist or a region where the number of bubbles is remarkably reduced is determined as a non-foamed layer, and the thickness of the non-foamed layer is measured. And an arithmetic average value.

  In the styrene-based foam laminate of the present invention, it is sufficient that it is formed on at least one side with respect to the foam layer, but it is formed on both sides in terms of securing a fastening force when fastening to other members with wood screws. Is more preferable.

  In the styrene-based foam laminate of the present invention, by controlling the foaming ratio at 1 mm immediately below the non-foamed layer, the strength when receiving a local force on the surface of the non-foamed layer can be increased and the thickness of the non-foamed layer Can be made thin, and both strength and light weight can be achieved.

The expansion ratio at 1 mm immediately below the non-foamed layer in the present invention is preferably 1.5 to 4.0 times, more preferably 2.0 to 3.5 times, and particularly preferably 2.0 to 3.0 times.
When the expansion ratio at 1 mm directly below the non-foamed layer is less than 1.5 times, the lightness tends to be inferior, and when it is more than 4 times, it is sufficiently fastened to other members with wood screws or the like. There may not be.

Here, the expansion ratio at 1 mm immediately below the non-foamed layer is a value measured by the following method.
A sample having a width of 150 mm and a length of 1820 mm is cut out from the center in the width direction from the obtained foamed laminate. Next, the cut sample weight A (g) was measured, and using a woodworking machine, the melting of the resin was not visually observed on the surface after cutting at the position of the thickness of the non-foamed layer + 1 mm from the surface. After cutting, the weight B (g) is measured.
From the obtained measured value, the density (g / cm ³ ) = {(A−B) − (182 × 15 × non-foamed layer thickness × 1.05)} / (182 × 15 × 0) immediately below the non-foamed layer. Calculate the density of 1 mm directly under the non-foamed layer based on the equation of .1).
A value obtained by dividing the polystyrene resin density of 1.05 g / cc by the density of 1 mm immediately below the obtained non-foamed layer was adopted as the foaming magnification of 1 mm immediately below the non-foamed layer.

  In the styrene foam laminate of the present invention, a foam laminate excellent in light weight can be obtained by controlling the expansion ratio of the entire foam laminate.

In the present invention, the expansion ratio of the entire foam laminate is preferably 3.0 to 10 times, more preferably 4.0 to 8.0 times, and particularly preferably 4.5 to 7.0 times.
When the foam ratio of the entire foamed laminate is less than 3.0 times, the lightness tends to be inferior, and when it is more than 10 times, it may be cracked when nailing, or may have inferior compressive strength. .

In the styrene-based foam laminate of the present invention, the surface hardness is preferably 400 to 1000N, more preferably 450 to 800N, and particularly preferably 500 to 700N.
If the surface hardness is less than 400N, it may be easy to loosen when fastened to other members using wood screws. When the surface hardness is larger than 1000 N, the thickness of the non-foamed layer may be thick, or the magnification of 1 mm immediately below the non-foamed layer may be low, resulting in poor lightness.

  Here, the surface hardness is a value obtained by the following method. That is, using a compression tester (manufactured by Shimadzu Corp., Autograph AG-X / R) for a test sample of length 30 mm × width 30 mm cut out from the foam laminate, the center of the non-foamed layer surface of the test sample When the steel ball having a diameter of 5 mm is left in place, the load at the yield point of the obtained stress-strain diagram when the test ball is pushed in at 5 mm in the vertical direction at a test speed of 1000 mm / min is determined as the hardness of the foam laminate. did.

In the styrene-based foam laminate of the present invention, the closed cell ratio of the foam laminate is preferably 75% to 100%, more preferably 80 to 100%, and 85 to 95%. Particularly preferred. The closed cell rate is a numerical value indicating the content rate of bubbles that do not have a hole, a deficiency, or the like in the bubble film in the bubbles constituting the foam.
When the closed cell ratio is lower than 75%, the compression strength may be inferior.

  In the styrenic foam laminate of the present invention, the total thickness of the foam laminate is preferably 6 to 30 mm, more preferably 8 to 28 mm, and particularly preferably 10 to 25 mm.

  The styrenic resin used in the present invention is not particularly limited, and is obtained from a styrene homopolymer obtained only from a styrene monomer; a monomer copolymerizable with styrene monomer and styrene, or a derivative thereof. Random, block or graft copolymers; post-brominated polystyrene, modified polystyrene such as rubber reinforced polystyrene, and the like. These can be used alone or in admixture of two or more.

  Examples of monomers copolymerizable with styrene include styrene derivatives such as 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, butyl acrylate, and acrylonitrile; Diene compounds or derivatives thereof; unsaturated carboxylic acid anhydrides such as maleic anhydride and itaconic anhydride. These can be used alone or in admixture of two or more.

  Among the styrene resins, styrene homopolymers, styrene acrylonitrile copolymers, (meth) acrylic acid copolymer polystyrene, maleic anhydride-modified polystyrene, impact-resistant polystyrene, and the like are preferable from the viewpoint of extrusion foam moldability and the like. Styrene homopolymer is more preferable from the viewpoint of cost.

  Further, the styrene resin used in the present invention is not limited to virgin resin, and recycled styrene resin can also be used. Examples include fish box EPS, home appliance cushioning materials, styrene resin foams such as food foam polystyrene trays, or polystyrene trays as refrigerator interior materials. Separately from this, a styrenic resin obtained by recycling cutting waste generated in the finish cutting process of the product can also be used. These styrenic resins may be fed as they are into the extruder, or may be reduced in volume and pelletized so as to be easily fed into the extruder.

Although it does not specifically limit as a foaming agent used by this invention, The outstanding environmental compatibility can be provided by using a C3-C5 saturated hydrocarbon.
Examples of the saturated hydrocarbon having 3 to 5 carbon atoms used in the present invention include propane, n-butane, i-butane, n-pentane, i-pentane, neopentane and the like. Among these saturated hydrocarbons having 3 to 5 carbon atoms, propane, n-butane, i-butane, or a mixture thereof is preferable from the viewpoint of foamability. In addition, n-butane, i-butane, or a mixture thereof is preferable because it is easily available.

  In the present invention, by using another foaming agent, a plasticizing effect and an auxiliary foaming effect at the time of foam production can be obtained, the extrusion pressure can be reduced, and the foam can be stably produced. However, depending on various properties of the foam having the desired expansion ratio, the amount of use may be limited, and the extrusion foam moldability may not be sufficient.

Other foaming agents include, for example, ethers such as dimethyl ether, diethyl ether, methyl ethyl ether, isopropyl ether, n-butyl ether, diisopropyl ether, furan, furfural, 2-methyl furan, tetrahydrofuran, tetrahydropyran; dimethyl ketone, methyl ethyl ketone , Diethyl ketone, methyl n-propyl ketone, methyl-n-butyl ketone, methyl-i-butyl ketone, methyl-n-amyl ketone, methyl-n-hexyl ketone, ethyl-n-propyl ketone, ethyl-n-butyl ketone, etc. A saturated alcohol having 1 to 4 carbon atoms such as methanol, ethanol, propyl alcohol, i-propyl alcohol, butyl alcohol, i-butyl alcohol, t-butyl alcohol; Organic esters such as acid methyl ester, formic acid ethyl ester, formic acid propyl ester, formic acid butyl ester, formic acid amyl ester, propionic acid methyl ester, propionic acid ethyl ester; alkyl halides such as methyl chloride and ethyl chloride A foaming agent, an inorganic foaming agent such as water or carbon dioxide, a chemical foaming agent such as an azo compound or tetrazole, or the like can be used. These other blowing agents may be used alone or in combination of two or more.
Among other foaming agents, C1-C4 saturated alcohol, dimethyl ether, diethyl ether, methyl ethyl ether, methyl chloride, ethyl chloride, etc. are mentioned from points, such as foamability and foam moldability.

  1-6 weight part is preferable with respect to 100 weight part of styrene resin, and, as for the usage-amount of the foaming agent in this invention, 1.5-4 weight part is more preferable. When the amount of the foaming agent used is less than 1 part by weight, the foaming ratio is low, and the lightness as a resin foam may be difficult to be exhibited. When the amount exceeds 6 parts by weight, the ratio is high, and as a result, the strength is not acceptable. There is a case.

In the present invention, if necessary, processing aids such as bubble regulators, fatty acid metal salts, fatty acid amides, fatty acid esters, liquid paraffin, olefinic wax, flame retardants, electrification, and the like within the range not inhibiting the effects of the present invention. Additives such as colorants such as inhibitors and pigments can be included.
Furthermore, in the present invention, if necessary, a stabilizer such as a phenol-based antioxidant, a nitrogen-based stabilizer, a sulfur-based stabilizer, a lactone-based stabilizer, a benzotriazole or a hindered amine-based agent is further contained. be able to.

  As a method for producing a foam layer in the styrene resin extruded foam laminate of the present invention, a styrene resin composition comprising a styrene resin and various additives is supplied to a heating and melting means such as an extruder, and high pressure is applied at an arbitrary stage. Under conditions, a foaming agent is added to the styrene resin, melt-kneaded, cooled to a temperature suitable for extrusion foaming, and then the styrene resin composition is extruded and foamed into a low pressure region through a mold to form a foam. It is manufactured by doing.

There are no particular restrictions on the heating temperature, melt kneading time, and melt kneading means when heating and kneading the styrene resin and additives such as a foaming agent.
Although heating temperature should just be more than the temperature which the styrene resin to use melt | dissolves, the temperature which suppresses the molecular degradation of resin as much as possible, for example, about 150-250 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 determined unconditionally. However, the time required for uniformly dispersing and mixing the styrene 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 degradation of the resin as much as possible, it is preferable to use a low shear type screw for the screw shape.

  Although the foam molding method is not particularly limited, for example, using a molding die having a certain gap in which a foam obtained by releasing pressure from the slit die is placed in close contact with or in contact with the slit die and / or a molding roll. A general method for molding a plate-like foam having a large cross-sectional area can be used.

As a method for forming the non-foamed layer in the present invention,
(A) a heat laminating method in which a non-foamed film or sheet is thermally fused to the surface of a separately obtained foam layer,
(B) A binder method in which the melted resin composition is extruded into a film on the surface of the obtained foamed layer, and immediately after that, pressure bonding and fusion are simultaneously performed with a cooling roll or the like,
(C) a hot melt bonding method in which a non-foamed film or sheet is bonded to the surface of the obtained foam layer via a film-like hot melt adhesive;
(D) When the foamed layer is extruded, the resin composition for forming the non-foamed layer is supplied to the flow path in the mold of the resin composition for forming the foamed layer by another extruder or the like, and the foamed layer resin composition A coextrusion method in which a foamed laminate having a non-foamed layer is formed by extruding from a mold after unifying the non-foamed layer resin composition,
(E) Immediately after extruding the foam, the surface of the foam is rubbed against a roll or the like to crush bubbles on the surface, and then cooled and solidified with a cooling roll or the like to form a non-foamed layer,
(F) An air cooling method for forming a non-foamed layer by cooling the foam surface with air immediately after the foam is extruded from the mold and suppressing foaming only on the foam surface;
(F) When the foam is extruded from the mold and shaped into a plate shape by the mold, the surface is cooled by the temperature-controlled mold to suppress foaming only on the foam surface. A cooling molding method for forming a non-foamed layer,
Etc.

  Among these, the cooling molding method is preferably used because the foamed layer and the non-foamed layer can be extruded at one time and the structure of the extrusion equipment is not complicated.

  The non-foamed layer in the present invention is not particularly limited, but a styrene resin is preferable from the viewpoint of recyclability.

The adjustment method of the expansion ratio in 1 mm directly under the non-foamed layer is
(1) Supply the resin composition adjusted to 1.5 to 4 times to the flow path in the mold of the resin composition that forms the foam layer when the foam layer is extruded by another extruder or the like. Then, after the resin composition adjusted so as to be 1.5 to 4 times the foam layer resin composition is united, it is extruded from a mold and has a foam layer having a foam layer of 1.5 to 4 times on the surface layer. Co-extrusion foaming method to obtain the body,
(2) In the cooling molding method described above, the foam layer is formed by a method of obtaining a foam by removing the foam surface layer portion extruded from the extrusion mold to the molding mold to 1.5 to 3 times. A method of forming a non-foamed layer by a heat laminating method, a binder method, or a hot-melt bonding method after obtaining a foam to constitute (3) In the above cooling molding method, immediately after being extruded from an extrusion die to a molding die The foam surface layer was removed by cooling with a molding die whose temperature was adjusted to 1.5 to 3 times, and immediately thereafter, the surface of the foam was cooled with a molding die with temperature control, and the surface was non-coated. A two-stage cooling method for forming a foam layer can be mentioned.
Among these, the two-stage cooling molding method is preferably used because the foamed layer and the non-foamed layer can be extruded at one time and the structure of the extrusion equipment is not complicated.

The two-stage cooling molding method will be briefly described with reference to FIG. 2, but is not limited thereto.
In the extruder, a styrenic resin composition adjusted to a resin temperature suitable for foaming is extruded into the atmosphere from the extrusion die 1, and then the fixed gap height set in close contact with the extrusion die 1 is set. Introduce into the mold 2 you have.
In the molding die 2, the upstream side and the downstream side of the molding die 2 are passed through a heat medium (upstream side heat medium 3, downstream side heat medium 4) adjusted in temperature upstream and downstream with respect to the extrusion direction. Adjust the temperature separately.
Here, the temperature of the heat medium in the molding die 2 varies depending on the discharge amount, the take-off speed, the resin temperature, and the amount of the foaming agent, and cannot be generally determined. It is preferable to adjust the temperature within the range of the glass transition temperature of the resin to the resin temperature, and the temperature of the downstream heat medium 4 is controlled within the range of the glass transition temperature of the styrene resin to (glass transition temperature −40 ° C.). It is preferable to do.
By setting the upstream portion of the molding die 2 as the decooling temperature region, the foaming ratio immediately below the non-foamed layer 1 mm in the laminated foam obtained can be adjusted, and by obtaining the downstream side as the cooling temperature region, it is obtained. The thickness of the non-foamed layer in the resulting laminated foam can be adjusted.
The foamed laminate formed by the molding die 2 is then taken up at a constant speed by the take-up drive roll 6 and then cut to obtain the styrene-based resin foamed laminate 5.

  The styrene resin foam laminate of the present invention is useful for various applications such as automobile members, building members, housing equipment members, packaging members, and the like due to its excellent performance.

  The form of use of the styrene resin foam laminate of the present invention is not particularly limited, but a film, sheet, or plate may be laminated and used by a method such as adhesion or heat fusion. . As another form of use, it may be used by being fixed to a steel material, a wood-based member or the like by a method such as adhesion or screwing.

  Next, the manufacturing method of the thermoplastic resin extrusion foam of this invention is demonstrated in detail based on an Example. However, the present invention is not limited to such an example.

  The evaluation methods implemented in the examples and comparative examples are as follows.

(1) Foaming magnification foam density of the entire foamed laminate (g / cm ³ ) = foam weight (g) / foam volume (cm ³ ) to obtain the foam density, and the obtained foam density The value obtained by removing the polystyrene resin density of 1.05 g / cc was taken as the foam magnification.

(2) Thickness of non-foamed layer Five samples of length 30 mm × width 30 mm were cut out at equal intervals in the width direction from the obtained foamed laminate.
For each of the obtained samples, an enlarged photograph (magnification: 200 times) of a cut surface in the vertical direction (thickness direction) cut along a line connecting the midpoints in the width direction is used with a microscope [manufactured by Sonic Corporation, Digital Photographed using a microscope BS-D8000]. From the photograph obtained, a region where no bubbles exist or the number of bubbles was remarkably reduced was judged as a non-foamed layer, and the thickness of the non-foamed layer was measured.
After performing the above measurement, the arithmetic average value of the obtained numerical values was adopted as the thickness of the non-foamed layer.

(3) Foaming magnification at 1 mm immediately below the non-foamed layer From the obtained foamed laminate, a sample having a width of 150 mm and a length of 1820 mm is cut out from the center in the width direction. Next, the cut sample weight A (g) was measured, and using a woodworking machine [manufactured by Amitech, vertical milling machine PV-70CA], the surface after cutting at the position of the non-foamed layer thickness + 1 mm from the surface After cutting so that the resin was not visually melted, the weight B (g) was measured.
From the obtained measured value, the density (g / cm ³ ) = {(A−B) − (182 × 15 × non-foamed layer thickness × 1.05)} / (182 × 15 × 0) immediately below the non-foamed layer. The density of 1 mm directly under the non-foamed layer was calculated based on the equation of .1).
The value obtained by dividing the polystyrene resin density of 1.05 g / cc by the density of 1 mm directly under the non-foamed layer was adopted as the magnification of 1 mm directly under the non-foamed layer.

(4) Hardness Five samples having a length of 30 mm and a width of 30 mm were cut out at equal intervals in the width direction of the obtained foamed laminate, and used as measurement samples. After the following test, the arithmetic average value of the obtained numerical values was adopted as the hardness.
Using a compression tester [manufactured by Shimadzu Corp., Autograph AG-X / R], a steel ball having a diameter of 5 mm was left at the center of the non-foamed layer surface of the foamed laminate, and then the test speed was 1000 mm / min. Then, the load at the yield point of the obtained stress-strain diagram when 5 mm was pushed in the vertical direction was defined as the hardness of the foamed laminate.

(5) Closed cell ratio A width of 150 mm × length of 600 mm was cut out from the obtained foamed laminate, and a non-foamed layer thickness +0.5 mm from the surface using a woodworking machine [manufactured by Amitech, vertical milling machine PV-70CA]. The thickness is cut so that melting of the resin is not visually recognized on the surface after cutting, and the opposite surface is also cut by the same method to remove the non-foamed layer. Next, 5 samples of 20 mm × 20 mm were cut out at equal intervals in the width direction of the foam layer.
For each of the obtained samples, the closed space volume Vc (cc) of the sample was measured using a pycnometer [manufactured by Tokyo Science Co., Ltd.]. Then, after measuring the volume Vo (cc) occupied by the outer shape of the sample, calculation was performed based on the formula of closed cell ratio = Vc / Vo × 100, and the arithmetic average value of the obtained numerical values was set as the closed cell ratio. Adopted.

(6) Compressive strength Five samples having a length of 30 mm and a width of 30 mm were cut out at equal intervals in the width direction from the obtained foamed laminate. For each sample, the compressive strength was measured according to JIS A 9511. The arithmetic average value of the obtained numerical values was adopted as the compressive strength.
And evaluation was performed based on the following evaluation criteria.
A: The compressive strength is 150 N / cm ² or more.
Δ: The compressive strength is 100 N / cm ² or more and less than 150 N / cm ² .
X: The compressive strength is less than 100 N / cm ² .

(7) Screw drawability Five samples of length 30 mm × width 30 mm were cut out at equal intervals in the width direction from the obtained foamed laminate, and wood screws (thickness 3) were vertically formed on the non-foamed layer surface. .8 mm × length 32 mm) was obtained by screwing in 8 mm.
For each measurement sample, using a tensile tester [manufactured by Shimadzu Corp., Autograph AG-X / R], grab the head of the wood screw and the foamed laminate, and pull it out at a test speed of 2.0 mm / min. The maximum load was obtained. The arithmetic average value of the obtained numerical values was adopted as the screw drawing strength.
Based on the following evaluation criteria, the screw pullability was evaluated.
○: Screw pullout strength is 150 N or more.
Δ: Screw drawing strength is 100N or more and less than 150N.
X: Screw drawing strength is less than 100N.

(8) Nailing property 20 samples having a length of 30 mm and a width of 30 mm were cut out from the obtained foamed laminate.
With respect to the obtained sample, an iron round nail (outer diameter: 3 mm) was struck in the center of the non-foamed layer surface using a hammer until the nail head subducted vertically, and the nailability was evaluated based on the following evaluation criteria. Went.
○: No cracks are observed in the non-foamed layer of all samples.
Δ: Cracks were observed in the non-foamed layers of 1 to 5 samples.
X: Cracks were observed in the non-foamed layer in 6 or more samples.

(9) Nail cracking property 20 samples 30 mm long by 30 mm wide were cut out from the obtained foamed laminate.
An iron round nail (outer diameter: 3 mm) was struck vertically with a hammer to the non-foamed layer at a position 8 mm inside from the cut end of the foamed laminate, and the nail cracking was evaluated based on the following evaluation criteria. went.
○: No chipping or cracking is observed in all foam laminates.
Δ: Chipping / cracking was observed in 1 to 5 samples.
X: Chipping / cracking was observed in 6 or more samples.

Example 1
3 parts by weight of talc [manufactured by Hayashi Kasei Co., Ltd., Talcan Powder PK-Z] was added to 100 parts of polystyrene resin [PS Japan Co., Ltd., 680] and dry blended. The obtained resin mixture is transferred to a tandem type two-stage extruder in which a single-screw extruder having a diameter of 65 mm (first extruder) and a single-screw extruder having a diameter of 90 mm (second extruder) are connected in series at 20 kg / hr. Was supplied at a rate of
The resin mixture supplied to the first extruder is heated to a resin temperature of 200 ° C. to be melted or plasticized and kneaded, and normal butane [manufactured by Iwatani Corporation] is used as a foaming agent near the tip of the first extruder. After press-fitting into the resin at a rate of 0.4 kg / hr, the resin temperature was cooled to 135 ° C. in the second extruder connected to the first extruder.
As shown in FIG. 2, the cooled foamable resin composition is extruded and foamed into the atmosphere from an extrusion mold having a rectangular cross section with a thickness of 2 mm × width of 180 mm provided at the tip of the second extruder, and then extruded. It was formed into a plate shape with a molding die having a gap height of 12.5 mm, a width of 300 mm, and a length of 100 mm, which was placed in close contact with the die. In the molding die, as shown in FIG. 2, a heat medium is passed in the width direction through 20 mm (upstream side of the molding die) and 80 mm (downstream side of the molding die) from the installation surface with the extrusion die. The temperature was adjusted. At that time, the temperature on the upstream side of the molding die was adjusted to 115 ° C., and the temperature on the downstream side was adjusted to 64 ° C.
Next, it took up with the take-up roll installed in the downstream, and obtained the foaming laminated body by which the non-foaming layer was formed in both surfaces of the cross-sectional shape which is thickness 12.7mm x width 242mm.
Table 1 shows the properties and physical properties of the obtained foamed laminate.

(Examples 2-6, Comparative Examples 1-5)
As shown in Table 1, in the same manner as in Example 1, except for changing the resin temperature, the foaming agent press-fitting amount, the molding die upstream side temperature control temperature, and the molding die downstream temperature control temperature, the foam laminate was obtained. Got.
Table 1 shows the properties and physical properties of the obtained foamed laminate.

(Example 7)
The foamed laminate obtained in Comparative Example 3 was fed out at a speed of 0.8 m / min, and on the surface of the non-foamed layer, a melted film-like polystyrene resin obtained under the following conditions [PS Japan Co., Ltd. ), 680] was extruded to a thickness of 0.2 mm, and immediately after pressing and solidifying with a cooling roll, a polystyrene-based resin foam laminate having a non-foamed layer formed on the foam surface was obtained.
The film-like polystyrene resin in the melted state is supplied to a twin screw extruder having a diameter of 30 mm at a rate of 5 kg / hr, and after being made into a molten state at a resin temperature of 200 ° C., at the tip of the twin screw extruder. The film was extruded from a connected T-die having a width of 650 mm. The non-foamed layer film protruding in the width direction of the obtained foamed laminate was removed to obtain a foamed laminate.
Table 1 shows the properties and physical properties of the obtained foamed laminate.

(Comparative Example 6)
3 parts by weight of talc [manufactured by Hayashi Kasei Co., Ltd., Talcan Powder PK-Z] was added to 100 parts of polystyrene resin [PS Japan Co., Ltd., 680] and dry blended. The obtained resin mixture is transferred to a tandem type two-stage extruder in which a single-screw extruder having a diameter of 65 mm (first extruder) and a single-screw extruder having a diameter of 90 mm (second extruder) are connected in series at 20 kg / hr. Was supplied at a rate of
The resin mixture supplied to the first extruder is heated to a resin temperature of 200 ° C. to be melted or plasticized and kneaded, and normal butane [manufactured by Iwatani Corporation] is used as a foaming agent near the tip of the first extruder. After press-fitting into the resin at a rate of 0.37 kg / hr, the resin temperature was cooled to 135 ° C. in the second extruder connected to the first extruder.
The cooled foamable resin composition was extruded and foamed into the atmosphere from a T-die having an opening with a thickness of 1.5 mm and a width of 250 mm provided at the tip of the second extruder as shown in FIG. . Next, the surface of the extruded foam is rubbed using a molding fixed roll temperature-controlled at 70 ° C., and immediately after cooling and solidified using a cooling free roll temperature-controlled at 30 ° C., a take-up drive It took up with the roll and obtained the foaming laminated body.
Table 1 shows the properties and physical properties of the obtained foamed laminate.

  As shown in Examples 1 to 7 and Comparative Examples 1 to 6, in the polystyrene-based resin foam laminate, the non-foam layer thickness, the foam magnification of 1 mm immediately below the non-foam layer, and the total magnification of the foam laminate are within a specific range. Thus, it can be seen that a foam laminate having excellent lightness and strength can be obtained.

DESCRIPTION OF SYMBOLS 1 Extrusion die 2 Molding die 3 Molding mold upstream temperature control heat medium pipe 4 Molding mold downstream temperature control heat medium pipe 5 Foamed laminate 6 Take-up drive roll 7 Extrusion mold (T die)
8 Molding fixed roll 9 Cooling free roll 10 Foam laminate

Claims (10)

A non-foamed layer having a thickness of 0.015 to 0.7 mm is formed on at least one surface in the thickness direction of a styrenic resin foam layer obtained by heating and melting a styrene resin, adding a foaming agent, and extruding and foaming the foaming agent. A formed styrene foam laminate,
The expansion ratio at 1 mm immediately below the non-foamed layer is 1.5 to 4 times ,
The expansion ratio of the total foam laminate comprising a non-foamed layer is Ri 3-10 Baidea and
The styrene-based foam laminate , wherein the foaming ratio at 1 mm immediately below the non-foamed layer is smaller than the foaming ratio of the whole foamed laminate. A non-foamed layer having a thickness of 0.015 to 0.7 mm is formed on at least one surface in the thickness direction of a styrenic resin foam layer obtained by heating and melting a styrene resin, adding a foaming agent, and extruding and foaming the foaming agent. A formed styrene foam laminate,
The expansion ratio at 1 mm immediately below the non-foamed layer is 1.5 to 3.8 times, and
A styrene-based foam laminate, characterized in that the expansion ratio of the entire foam laminate including a non-foam layer is 3.8 to 10 times. The expansion ratio at 1 mm immediately below the non-foamed layer is 1.5 to 3.5 times,
The styrene foam laminate according to claim 2, wherein the expansion ratio of the entire foam laminate is 3.8 to 10 times. The expansion ratio at 1 mm immediately below the non-foamed layer is 1.5 to 3.8 times,
The styrene-based foam laminate according to claim 2, wherein the foaming magnification of the whole foam laminate is 4.0 to 10 times. The surface hardness of the non-foamed layer is 400N to 1000N, and the styrene resin extruded foam laminate according to any one of claims 1 to 4 . The styrene resin extruded foam laminate according to any one of claims 1 to 5, wherein the closed cell ratio of the foam layer is 75% or more. A method for producing a foam laminate including a styrene resin foam layer obtained by heating and melting a styrene resin, adding a foaming agent, and extruding and foaming the foaming agent,
A non-foamed layer having a thickness of 0.015 to 0.7 mm is formed on at least one surface of the foamed layer, and the foaming ratio at 1 mm immediately below the non-foamed layer is 1.5 to 4 times. magnification Ri 3-10 Baidea, and said non-foaming expansion ratio immediately below 1mm of layer, characterized in that said foam laminate overall expansion ratio smaller, the manufacturing method of the styrenic foam. A method for producing a foam laminate including a styrene resin foam layer obtained by heating and melting a styrene resin, adding a foaming agent, and extruding and foaming the foaming agent,
A non-foamed layer having a thickness of 0.015 to 0.7 mm is formed on at least one surface of the foamed layer, and the foaming ratio at 1 mm immediately below the non-foamed layer is 1.5 to 3.8 times. A method for producing a styrene-based foam, wherein the overall magnification is 3.8 to 10 times. The expansion ratio at 1 mm immediately below the non-foamed layer is 1.5 to 3.5 times,
The method for producing a styrene-based foam according to claim 8, wherein the expansion ratio of the entire foam laminate is 3.8 to 10 times. The expansion ratio at 1 mm immediately below the non-foamed layer is 1.5 to 3.8 times,
The method for producing a styrenic foam according to claim 8, wherein the expansion ratio of the entire foam laminate is 4.0 to 10 times.

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