JPH11300840A - Production of deformed thermoplastic resin foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for simply producing a deformed thermoplastic resin foam having grooves of which the depth is 30% or more of the width thereof formed thereto in good productivity without requiring a large-sized expensive device. SOLUTION: A foamable thermoplastic resin sheet material obtained by supplying a compsn. containing high density polyethylene, polypropylene, crosslinkable silane modified polypropylene and azodicarbonamide to an extruder is foamed to obtain a thermoplastic resin foam 4 and a groove forming jig (made of aluminum, W=10 mm, h=15 mm, a depth of a cross-sectional parallel part is 10 mm and the cross section of the deepest part is a semicircular shape R of 10 ϕ) heated to 180 deg.C is pressed to the foam to obtain a deformed thermoplastic resin foam A having clear grooves of which the depth is 30% or more of the width thereof formed to the surface thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a deformed thermoplastic resin foam having a groove and suitable for use as a flooring material for heating.

[0002]

2. Description of the Related Art In recent years, due to an increase in demand for floor heating, a demand for a thermoplastic resin foam having a concave groove for laying a hot water pipe has been increasing. In general, as a method for producing a thermoplastic resin foam having a groove formed therein, a method of introducing a resin into a closed mold and subjecting the resin to heat molding and foaming, or a method of temporarily obtaining a foam having a predetermined shape, and then performing mechanical cutting to form the concave. A method of providing a groove and the like are known.

However, in the method using the above-mentioned closed mold typified by expanded polystyrene, for example, every time the desired shape is changed, a large-scale molding die corresponding to the shape must be prepared, and the molding die There is a problem that the cost is very high, and in addition, there is a problem that it is impossible to continuously produce a foam having a concave groove because a closed mold is used. In addition, the above cutting method has a problem in productivity.

Therefore, in order to improve the above problem,
As shown in FIG. 5, ridges 11a for providing a concave groove,
11b, a first endless belt 11 provided on the outer surface and a second endless belt 12 are conveyed in a state where they face each other with a predetermined gap D therebetween. A method for producing a foam having a concave groove, comprising supplying a foamable resin granule A containing a foaming agent and heating the foamed resin granules in the gap D in the heating device 15 to a temperature equal to or higher than the decomposition temperature of the pyrolytic foaming agent. Has been proposed (see JP-A-8-281680).

However, the above-described method for producing a foam also requires a large-scale apparatus, and the first endless belt 11 is provided with a ridge. There is a problem that the distribution in the vicinity of the ridges 11a and 11b is disturbed, and it is difficult to obtain a uniform foam.

[0006]

SUMMARY OF THE INVENTION In view of the above prior art, the present inventor has found that in order to find a simple method of producing a foam having a concave groove, the thermoplastic resin foam itself is heated, and then a cooling jig is mounted. A deep groove was not formed except when the groove was pressed to form the groove, and the foam itself warped and the like, so that practical use was difficult. SUMMARY OF THE INVENTION An object of the present invention is to provide a simple and convenient method for producing a deformed thermoplastic resin foam having a groove having a depth of 30% or more of its width without requiring a large-scale expensive apparatus. Is to do.

[0007]

According to the first aspect of the present invention, there is provided a method for producing a deformed thermoplastic resin foam, wherein the thermoplastic resin foam is heated to a temperature exceeding the melting point of the thermoplastic resin. A groove having a depth of 30% or more of the groove width is formed on the surface of the foam by pressing the heated groove forming jig. The manufacturing method according to the second aspect of the present invention (the invention according to the second aspect) is the same as the manufacturing method according to the first aspect, except that
The thermoplastic resin has a weight ratio of the non-crosslinked polyethylene resin to the non-crosslinked polypropylene resin of 2: 8 to 8: 2, the total amount of which is 100 parts by weight, and the crosslinkable silane-modified polypropylene-based resin is 1 to 50 parts by weight. And is characterized by containing.

According to a third aspect of the present invention, there is provided the method according to the first or second aspect, wherein the polyolefin resin is contained in the thermoplastic resin in an amount of 80% by weight or more, and The gel fraction is 3% to 45%.

Thermoplastic Resin In the method for producing a deformed thermoplastic resin foam of the present invention 1, the resin constituting the thermoplastic resin foam is not particularly limited as long as it is a foamable thermoplastic resin. . As such a thermoplastic resin, for example, low-density polyethylene, high-density polyethylene, linear low-density polyethylene (hereinafter, “polyethylene” refers to low-density polyethylene, high-density polyethylene, linear low-density polyethylene, or These may be referred to as a mixture thereof), random polypropylene, homopolypropylene, block polypropylene (hereinafter, "polypropylene" may refer to random polypropylene, homopolypropylene, block polypropylene, or a mixture thereof) and the like. Olefin-based resins, and olefin-based copolymers such as ethylene-vinyl acetate resin; ABS resins, polystyrene, and copolymers using these monomers as comonomers; and the like, even when used alone or in combination. You may.

The foam of the thermoplastic resin used in the present invention 1 is preferably crosslinked as described later. As a crosslinking method, for example, a crosslinkable silane-modified resin (silane-grafted polymer) may be used. After melting and kneading, a method of crosslinking by performing a water treatment, melting and kneading an organic peroxide to a thermoplastic resin at a temperature lower than the decomposition temperature of the peroxide, and then heating to a temperature equal to or higher than the decomposition temperature of the peroxide to crosslink. And a method of cross-linking by irradiating ionizing radiation such as α-ray, β-ray, γ-ray, electron beam, and the like.Since the cross-linking after mixing of each component is easy, the silane graft polymer is treated with water. The method of crosslinking is most preferred. The amount of the organic peroxide is usually 0.5 to 5 parts by weight based on 100 parts by weight of the resin, and the amount of the ionizing radiation is usually 1 to 10 Mrad.
It is. In this case, an appropriate crosslinking aid may be used in combination.

[0011] More specifically, it has a microstructure in which crosslinked polypropylene is dispersed in a partially non-crosslinked polyethylene portion, and the flow shapeability of the foam by the heated groove forming jig is improved. As in the second aspect of the present invention, the thermoplastic resin has a weight ratio of a non-crosslinked polyethylene resin to a non-crosslinked polypropylene resin of 2: 8 to 8: 2, and a total amount of 100 parts by weight and a crosslinkable silane-modified polypropylene. It is preferable that 1 to 50 parts by weight of the system resin is contained.

Further, the difference between the melt index (hereinafter referred to as MI) of the non-crosslinked polyethylene resin and the non-crosslinked polypropylene resin is preferably 5 in that a more microscopic and uniform sea-island structure can be formed. ~ 13g / 10min,
More preferably, the weight ratio is 7 to 11 g / 10 min, and the weight ratio of both is still more preferably 4: 6 to 6: 4. The difference in MI between the crosslinkable silane-modified polypropylene-based resin and the non-crosslinked polypropylene-based resin is 1 g / g. It is preferably 10 minutes or less.
If the MI difference between the crosslinkable silane-modified polypropylene resin and the non-crosslinkable polypropylene resin is greater than 1 g / 10 minutes, the crosslinkable silane-modified polypropylene resin is mixed with a non-crosslinked polyethylene resin and a non-crosslinked polypropylene resin. This is because it may not be possible to preferentially dissolve in the non-crosslinked polypropylene resin therein. In addition,
MI in the present specification is a value measured according to JIS K7210.

Further, in the present invention 1 or 2, as in the present invention 3, the thermoplastic resin contains at least 80% by weight of a polyolefin resin, and the gel fraction of the entire thermoplastic resin is 3%. It is preferably about 45%. When the polyolefin resin is less than 80% by weight, the shape of the groove formed in the thermoplastic resin foam becomes defective,
If the entire foam is warped, and if the gel fraction is less than 3%, the heat resistance and strength are too low, and if it exceeds 45%, the fluid shaping property of the foam during heating is insufficient. This is also not preferable for the formation of the concave groove according to the present invention. The gel fraction in this specification refers to the weight percentage of the weight of the residue after immersing the crosslinked resin component in xylene at 120 ° C. for 24 hours with respect to the weight of the crosslinked resin component before immersion in xylene. Is an index for estimating the crosslinking ratio of The silane-grafted polymer such as the crosslinkable silane-modified polypropylene resin can be obtained by, for example, graft-modifying the polymer with an unsaturated silane compound.

The unsaturated silane compound is represented by the general formula R1
Refers to a compound represented by SiR2mY3-m. Here, m is 0, 1, or 2. In the formula, R1 represents an alkenyl group such as a vinyl group, an allyl group, a propenyl group, a cyclohexenyl group; a glycidyl group; an amino group; a methacryl group;
Organic functional groups such as halogenated alkyl groups such as chloroethyl group and γ-bromoethyl group.

In the formula, R2 represents an aliphatic saturated hydrocarbon group or an aromatic hydrocarbon group, for example, a methyl group, an ethyl group,
Examples thereof include a propyl group, a decyl group, and a phenyl group. In the formula, Y represents a hydrolyzable organic functional group, for example, a methoxy group, an ethoxy group, a formyloxy group, an acetoxy group, a propionoxyarylamino group, and the like.
Is 0 or 1, Y may be the same or different.

In order to increase the rate of the crosslinking reaction, the unsaturated silane compound may be represented by the general formula CH 2 2CHSi (O
A) Those represented by 3 are preferred. In the formula, A is preferably an aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably 1 to 4 carbon atoms. CH2 = CHSi (OA) 3
Preferred unsaturated silane compounds represented by are, for example, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane and the like.

When the silane-crosslinkable polypropylene resin is produced, there is no particular limitation. For example, an unsaturated silane compound represented by R1SiR2Y3-m and an organic peroxide are reacted with the polypropylene resin to obtain a silane-crosslinkable polypropylene resin. A method of obtaining a modified polypropylene or the like can be given.

The silane graft polymer having a silyl group, for example, when Y is a methoxy group, is hydrolyzed to a hydroxyl group by contact with water when Y is a methoxy group.
Hydroxyl groups of different molecules react with each other to form a Si—O—Si bond, and the silane graft polymers are crosslinked.

The above-mentioned water treatment methods include a method of immersion in water and a method of exposure to water vapor.
When the treatment is performed at a temperature higher than 00 ° C., the treatment may be performed under pressure. If the temperature at this time is too high, a problem occurs in which the foamable thermoplastic resin melts and adheres. If the temperature is too low, the crosslinking reaction speed decreases.
0-120 degreeC is more preferable.

If the amount of the silane-grafted polymer such as silane-grafted polypropylene is too large, crosslinking is excessively performed, and the shapeability of the obtained foam is deteriorated. Since a suitable foam cell cannot be obtained, the blending amount of the silane graft polymer is usually 5 to 55% by weight, preferably 20 to 35% by weight based on the total thermoplastic resin. Also, the degree of crosslinking of the silane graft polymer itself such as silane graft polypropylene is the ultimate gel fraction,
It is preferably from 60 to 85%, and the gel fraction in the entire thermoplastic resin is preferably from 3 to 45%.

When silane crosslinking is performed using a silane graft polymer, the silane crosslinking catalyst used as necessary is not particularly limited as long as it promotes a crosslinking reaction between the silane graft polymers. For example, dibutyltin diacetate, dibutyltin dilaurate, dioctyltin dilaurate, tin octoate, tin oleate, lead octane, zinc 2-ethylhexanoate, cobalt octoate, lead naphthenate, zinc cabrate, zinc stearate And the like, and usually 0.01 to 1 part by weight based on 100 parts by weight of the resin.

The method of mixing the silane graft polymer is as follows:
There is no particular limitation on the method as long as it can be uniformly mixed. For example, a method in which a thermoplastic resin and a silane graft polymer are supplied to a single-screw or twin-screw extruder and melt-kneaded, a method of melt-kneading using a roll, a method of melt-kneading using a kneader, and the like are exemplified.

[0023] In the production method of the modified thermoplastic resin foam of the foam present invention the thermoplastic resin, for foam and its manufacturing method of the thermoplastic resin, but are not limited in any way, are described below When a foamable thermoplastic resin sheet is once formed and then heated and foamed, a deformed thermoplastic resin foam having high compressive strength and suitable for use as a flooring material for heating is obtained.

First, an example of a method for producing a foamable thermoplastic resin sheet will be described. A foamable thermoplastic resin composition obtained by adding a pyrolytic foaming agent represented by, for example, azodicarbonamide to the above thermoplastic resin is supplied to an extruder 5 shown in FIG. After melt-kneading at a temperature lower than the decomposition temperature of, the sheet-like foamable thermoplastic resin in a softened state is discharged from the T-die 6, and further has a clearance smaller than the thickness of the sheet-like foamable thermoplastic resin,
It is introduced into a pair of rolls including a shaping roll 7 in which a large number of recesses 7a are uniformly arranged on the outer circumferential surface and a shaping roll 8 whose outer circumferential surface rotates in a different direction from the shaping roll 7 and is softened into the recesses 7a. After press-fitting a part of the sheet-like foamable thermoplastic resin in the state, cooling and release are performed.

Suspended foamable thermoplastic resin sheet 1
The foamable thermoplastic resin granules 2 are arranged substantially uniformly in a plane, and the foamable thermoplastic resin granules are integrally connected via a foamable thermoplastic resin thin film 3. The shape of the foamable thermoplastic resin granules is not particularly limited, but when formed in a columnar shape and arranged in a staggered manner, foaming is performed uniformly, and individual foamable thermoplastic resin granules are formed. Since the foam part obtained by foaming becomes a hexagonal column shape and constitutes a pseudo honeycomb structure,
This is preferable in that a foam having improved compressive strength can be obtained.

When the expandable thermoplastic resin particles 2 are cylindrical, the diameter is preferably 1 mm to 30 mm, more preferably 2 mm to 20 mm, and the height is 1 mm.
mm to 30 mm is preferable, and more preferably 2 mm to 2 mm.
The range is 0 mm. The center-to-center distance between the foamable thermoplastic resin particles is preferably 2 mm to 50 mm, and 3 mm to 3 mm.
0 mm is particularly preferred.

The foamable thermoplastic resin sheet is heated to a temperature equal to or higher than the decomposition temperature of the foaming agent, foamed, and cooled appropriately to obtain a thermoplastic resin foam suitably used in the present invention.

Forming a Concave Groove The method for producing a deformed thermoplastic resin foam according to the first aspect of the present invention is characterized in that the above-mentioned thermoplastic resin foam is provided with a concave heated to a temperature exceeding the melting point of the thermoplastic resin constituting the foam. Although the groove forming jig is pressed, the melting point in the present specification means a value of an endothermic peak measured by a differential calorimeter (abbreviated as DSC), and is obtained by mixing a plurality of resins. When used, it refers to the temperature at which at least 70% by weight melts. For example, the groove forming jig 10 shown in FIG. 2 has a configuration in which a ridge 9 a corresponding to the groove to be formed is erected from the substrate 9. The material of the groove forming jig is preferably a metal or alloy such as aluminum, copper, iron, zinc, and stainless steel.

The jig for forming the groove is heated to a temperature exceeding the melting point of the thermoplastic resin, preferably to a temperature higher than the melting point by 10 ° C. or more.
To form a concave groove 9b for heating piping, for example, to obtain a deformed thermoplastic resin foam A. However, heating to an excessively high temperature causes deterioration and deterioration of the resin. Therefore, the temperature is usually set to 250 ° C. or lower, and preferably 220 ° C. or lower in terms of workability and thermal efficiency. The depth of the concave groove 9b is such that a deep groove having a depth of 30% or more of the concave groove width W is formed based on the depth h of the deepest portion. In the method for producing a deformed thermoplastic resin foam according to the second or third aspect of the present invention, the formation of the concave groove is the same as that of the present invention except that the type of resin used in the thermoplastic resin foam or the gel fraction is different. Same as 1.

[0030]

(Example 1) High-density polyethylene (manufactured by Mitsubishi Chemical Corporation, trade name "HY340", melting point 133 ° C, MI =
25 parts by weight of 1.5 g / 10 min, specific gravity 0.952), high-density polyethylene (manufactured by Mitsubishi Chemical Corporation, trade name "HJ381")
P ", MI = 9.0 g / 10 min, melting point 132 ° C., specific gravity 0.951) 25 parts by weight, polypropylene (manufactured by Mitsubishi Chemical Corporation, trade name“ MA3 ”, melting point 151 ° C., MI = 11 g /
29 minutes by weight, 10 minutes, specific gravity 0.900) crosslinkable silane-modified polypropylene (manufactured by Mitsubishi Chemical Corporation, trade name "XPM80")
0HM ", MI = 11 g / 10 min, gel fraction after crosslinking 8
0 parts by weight) 21 parts by weight, azodicarbonamide (manufactured by Otsuka Chemical Co., Ltd., product number "SO-20", decomposition temperature 201 ° C) 9 parts by weight, and dibutyltin dilaurate as a silane crosslinking catalyst (manufactured by Mitsubishi Chemical Corporation, trade name) A composition containing PZ-10S, 1 part by weight of a master batch) was supplied to the twin-screw extruder 5 shown in FIG. The twin screw extruder 5 has a diameter of 44 m.
m. In a twin-screw extruder 5, the composition is melt-kneaded at 180 ° C., and the lip length is 300 mm.
A sheet-shaped foamable thermoplastic resin in a softened state was extruded by a 5 mm T-die 6.

Further, a recess 7 having a height of 5 mm and a diameter of 4 mm
a is arranged in a staggered manner, with a diameter of 250 mm and a surface length of 300
The foamable thermoplastic resin sheet is cooled while shaping it between the rolls 7 and 8 mm, and the foamable thermoplastic sheet is immersed in water at 98 ° C. for 2 hours and then dried to form a foam. The thermoplastic resin sheet 1 was obtained. The gel fraction of the sheet 1 was 15% according to the above-described measurement method.

In the foamable thermoplastic resin sheet obtained as described above, the foamable thermoplastic resin granules 2 (a high-temperature film not including a thin film 3 described later) are formed at a portion corresponding to the concave portion 7a of the shaping roll 7. 5 mm), and the expandable thermoplastic resin granular material 2 has a thickness of 0.4 mm at its end.
Are connected by the expandable thermoplastic resin thin film 3 to form the expandable thermoplastic resin sheet 1 as a whole.

The obtained foamable thermoplastic resin sheet 1
Is placed on a polytetrafluoroethylene sheet and supplied to endless belts 11 and 12 made of a material having excellent releasability in the production apparatus shown in FIG. The foam was heated and foamed to obtain a foam 4.

In FIG. 4, an endless belt 11 and an endless belt 12 are conveyed in the direction indicated by arrow X, and the endless belt 11 is stretched between rollers 13a to 13d to form rollers 13a to 13d. Either of them is connected to a rotary drive source such as a motor (not shown), and the endless belt 11 is conveyed in the arrow X direction shown by rotating the rotary drive source. On the other hand, the endless belt 12
Is wound between the rollers 14a to 14d, and at least one of the rollers 14a to 14d is connected to a rotary drive source such as a motor. By driving the rotary drive source, the endless belt 12 is conveyed in the direction indicated by the arrow X in the figure.

The endless belts 11 and 12 are
b from the position where the roller 13b is provided to the position where the rollers 13c and 14c are provided with a predetermined gap D therebetween.
Heating and cooling are performed in a region between the positions c and 14c to form a foam.

The feed rate of the foamable thermoplastic resin sheet 1 is 0.5 mm / min, and the heating device 15 is 5 m long.
m, temperature 210 ° C., cooling device 16 is 5 mm long,
The temperature was 30 ° C. The resulting foam is 17mm thick,
FIG. 2 shows an expansion ratio of 20 times and heating to 180 ° C.
Jig (aluminum, W = 10m)
m, h = 15 mm, the depth of the cross-section parallel portion was 10 mm, the cross-section of the deepest portion was semicircular, and R was 10φ) 10 to press the groove.

The deformed thermoplastic resin foam thus obtained has a clearly defined groove corresponding to the jig dimensions.
No warpage or curvature of the foam itself was observed. Also,
When the foam having the grooves was subjected to a heat resistance test in which the foam was left in an oven at 100 ° C. for 24 hours, no deformation of the grooves was observed, and it was confirmed that the heat resistance was good.

Example 2 Each resin was mixed with high-density polyethylene (trade name “HY340”, manufactured by Mitsubishi Chemical Corporation) 20
Parts by weight, 15 parts by weight of high density polyethylene (manufactured by Mitsubishi Chemical Corporation, trade name "HJ381P"), 40 parts by weight of polypropylene (manufactured by Mitsubishi Chemical Corporation, trade name "MA3"), and crosslinkable silane-modified polypropylene (manufactured by Mitsubishi Chemical Corporation, Product name "XP
M800HM ”) A softened sheet-like foamable thermoplastic resin was extruded in the same manner as in Example 1 except that the composition was changed to 25 parts by weight, and a foamable thermoplastic resin sheet was obtained. 1 was obtained. The gel fraction of the sheet 1 was 20%. The sheet 1 was supplied to the foam manufacturing apparatus shown in FIG. 4 and heated and foamed in the same manner as in Example 1 to obtain a foam 4 having a thickness of 13 mm and an expansion ratio of 12 times.

A jig for forming a concave groove (aluminum, W = 10 mm, shown in FIG. 2) heated to 180 ° C. The depth of the parallel portion was changed to 5 mm, and the deepest portion was a semicircle. As a result, h = 10 m
m) 10 was pressed to form a concave groove.

The deformed thermoplastic resin foam thus obtained has clear grooves corresponding to the jig dimensions.
No warpage or curvature of the foam itself was observed. Also,
When the foam having the grooves was subjected to a heat resistance test in which the foam was left in an oven at 100 ° C. for 24 hours, no deformation of the grooves was observed, and it was confirmed that the heat resistance was good. (Comparative Example 1) Low-density polyethylene (manufactured by Mitsubishi Chemical Corporation, trade name "LE520H", melting point 115 ° C, specific gravity 0.923,
MI = 4.0 g / 10 min) 100 parts by weight, azodicarbonamide (manufactured by Otsuka Chemical Co., Ltd., product number “SO-20”, decomposition temperature 201 ° C.) 10 parts by weight, 2,6-di-t-butyl-p-
Cresol (antioxidant) 0.3 part by weight, dilauryl thiopropionate (antioxidant) 0.3 part by weight and methylbenzotriazole (metal harm inhibitor) 0.5 part by weight, the temperature was 190 ° C. The kneading was carried out in the same manner as in Example 1 except that the kneading was performed to obtain a continuous sheet having a thickness of 2.5 mm.

[0041] This sheet is provided with 1000 kV and 3 Mrad.
Was irradiated to obtain a crosslinked sheet. This crosslinked sheet was continuously foamed in a vertical hot-air foaming furnace. Foaming was performed in a foaming furnace maintained at 250 ° C. by hot air and an infrared heater. When the groove forming jig 10 used in Example 1 heated to 100 ° C. was pressed against the obtained foam (expansion ratio 25 times, gel fraction 38%) to form a groove,
The shape of the concave groove was poor (the cross-sectional semicircular portion had a depth of only 3 mm), and the foam was warped or curved.

(Comparative Example 2) As a foam, a polystyrene foam (manufactured by Dow Chemical Co., Ltd., trade name: Styrofoam R)
B-GK, using a resin melting point of about 240 ° C., an expansion ratio of 30 times, and a thickness of 12 mm) and pressing the groove forming jig 10 used in Example 1 heated to 100 ° C. to form a groove. , Groove shape is poor (semicircular section width is 13m
m and the depth was only 3 mm)
In addition, the foam was warped and curved.

[0043]

According to the method for producing a deformed thermoplastic resin foam of the present invention 1, a groove forming jig heated to a temperature exceeding the melting point of the thermoplastic resin is pressed against the thermoplastic resin foam. Thus, a groove having a depth of 30% or more of the groove width is formed on the surface of the foam. Therefore, according to the first aspect of the present invention, the production can be easily performed without using a large-scale expensive apparatus. It is possible to provide a deformed thermoplastic resin foam having a well-formed, deep concave groove. In the method for producing a deformed thermoplastic resin foam according to the second aspect of the present invention, the thermoplastic resin has a weight ratio of a non-crosslinked polyethylene resin to a non-crosslinked polypropylene resin of 2: 8 to 8: 2, and the total amount is 100. 1 part by weight and 1 to 50 parts by weight of a crosslinkable silane-modified polypropylene-based resin, so that the thermoplastic resin has a microstructure in which a crosslinked polypropylene is dispersed in a partially non-crosslinked polyethylene portion. Thus, the flow shapeability of the foam by the heated groove forming jig is improved, and a deformed thermoplastic resin foam in which a groove having a better shape is formed can be obtained.

The method for producing a deformed thermoplastic resin foam according to the third aspect of the present invention is characterized in that a polyolefin resin is contained in the thermoplastic resin.
At least 3% by weight
Since it is about 45%, the fluidity of the thermoplastic resin is appropriate, the shape of the concave groove does not become defective, and the entire foam does not warp or curve. Is obtained.

[Brief description of the drawings]

FIG. 1 is a partial schematic cross-sectional view for explaining a step of manufacturing a foamable thermoplastic resin sheet used in Example 1.

FIG. 2 is a sectional view of a main part showing an example of a groove forming jig used in the present invention.

FIGS. 3A and 3B show a thermoplastic resin foam having a groove formed according to the present invention, wherein FIG. 3A is a plan view, and FIG.
FIG.

FIG. 4 is a schematic perspective view showing a thermoplastic resin foam manufacturing apparatus used in Example 1 before forming a concave groove.

FIG. 5 is a schematic perspective view showing an example of a conventionally used apparatus for manufacturing a thermoplastic resin foam having concave grooves.

[Explanation of symbols]

 Reference Signs List A Amorphous thermoplastic resin foam 1 Foamable thermoplastic resin sheet 2 Foamable thermoplastic resin granule 3 Foamable thermoplastic resin thin film 4 Thermoplastic foam 9b Groove 10 Jig for groove formation 11 Endless Belt 12 Endless belt

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29K 105: 04 B29L 16:00

Claims (3)

[Claims] 1. A groove for forming a groove, which is heated to a temperature exceeding the melting point of the thermoplastic resin, is pressed against the foam of the thermoplastic resin by 30% or more of the width of the groove on the surface of the foam. A method for producing a deformed thermoplastic resin foam, comprising forming a concave groove having a depth of: 2. The thermoplastic resin according to claim 1, wherein the weight ratio of the non-crosslinked polyethylene resin to the non-crosslinked polypropylene resin is 2: 8 to
The method for producing an irregularly shaped thermoplastic resin foam according to claim 1, wherein the ratio is 8: 2 and the total amount is 100 parts by weight and 1 to 50 parts by weight of a crosslinkable silane-modified polypropylene resin is contained. . 3. The thermoplastic resin according to claim 1, wherein the thermoplastic resin contains at least 80% by weight of a polyolefin resin, and the total gel fraction is 3% to 45%. A method for producing a deformed thermoplastic resin foam.