JP2010095564A - Foam, laminated foam and interior part for automobile obtained by using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a foam and a laminated foam that are excellent in light resistance and heat resistance and enhanced in touch and feeling and are suitably employable for automobile interior decoration, and an interior part for an automobile obtained by using the same. <P>SOLUTION: The foam 1 is obtained by expanding a thermoplastic elastomer having a shore A hardness of at least 60 and contains a plurality of micropores (a second micropore) 3 having a circumferential length of the micropore of at least 400 μm. Preferably, the foam 1 contains a first micropore 2 having a circumferential length of the micropore of less than 400 μm and the second micropore 3 having a circumferential length of the micropore of at least 400 μm, and the ratio of the porosity of the first micropore 2 to the porosity of the second micropore 3 is 1:0.7 to 1:1.5. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a foam obtained by foaming a thermoplastic elastomer having a specific hardness, and more particularly, a foam including a pore having a specific peripheral length, a laminated foam, and an automobile interior part using the same. About.

  Conventionally, automotive interior parts such as steering, seats, doors, instrumental panels, assist grips, and grips have been required to have good tactile sensation, and application of soft materials has been studied.

As interior parts for automobiles, for example, a skin material made of a thermoplastic elastomer having a relatively high hardness and a laminate in which polyurethane foam or the like is laminated on one surface of the skin material have been proposed (Patent Document 1). ).
Further, as interior materials for automobiles and the like, a skin layer (I) made of a thermoplastic elastomer having a Shore A hardness of 55 to 96, a foamed layer (II), and a base material layer (III) made of a wood-based phenol resin A multilayer laminate comprising at least three layers is also proposed (Patent Document 2).
JP-A-2005-247756 JP-A-9-11384

As in the above Patent Documents 1 and 2, automotive interior parts are generally laminated on the back surface of a skin material made of a high-hardness thermoplastic elastomer with a foam or the like in order to provide softness. The present condition is that the soft feel and texture of the skin material itself cannot be produced.
In order to give a soft touch, it is conceivable to use a low-hardness thermoplastic elastomer as the skin material. However, a low-hardness thermoplastic elastomer becomes soft due to large changes in gloss when exposed to light or heat. It may be too much or sticky.

  The present invention has been made in view of such problems of the prior art, and the object thereof is excellent as light and heat resistance, and is suitable as an automobile interior material with improved tactile feel and texture. An object of the present invention is to provide a foam that can be used, a laminated foam, and an automobile interior part using the same.

  As a result of intensive studies to achieve the above object, the present inventors can achieve the above object by foaming a relatively high hardness thermoplastic elastomer and containing pores of a predetermined size. As a result, the present invention has been completed.

  That is, the foam of the present invention is formed by foaming a thermoplastic elastomer having a Shore A hardness of 60 or more, and includes a plurality of pores having a pore perimeter of 400 μm or more.

  According to the present invention, a thermoplastic elastomer having a Shore A hardness of 60 or more is foamed to contain a plurality of pores of a predetermined size, thereby improving light resistance and heat resistance, and improving touch and texture. Further, it is possible to provide a foam, a laminated foam, and an automobile interior part using the same, which can be suitably used as an automobile interior material.

Hereinafter, the foam of this invention, a laminated foam, and the interior component for motor vehicles using the same are demonstrated.
The foam of the present invention is obtained by foaming a thermoplastic elastomer having a Shore A hardness of 60 or more and containing a plurality of pores having a pore perimeter of 400 μm or more.
In the foam of the present invention, since the thermoplastic elastomer constituting the foam has a Shore A hardness of 60 or more, preferably a Shore A hardness of 60 to 90, the foam becomes too soft even when exposed to light or heat. The light resistance, heat resistance and tactile sensation are excellent without causing stickiness or stickiness.
Shore A hardness refers to a value measured in accordance with JIS K6253, and indicates a value when a thermoplastic elastomer containing no pores (not foamed) is measured.

The foam of the present invention contains a plurality of pores having a pore perimeter of 400 μm or more, preferably 400 to 1000 μm.
Since the foam contains a plurality of pores having a pore perimeter of 400 μm or more, even if a relatively high hardness thermoplastic elastomer is used, a moderately soft touch and softness can be obtained. Can give a texture.
If the perimeter of the pores contained in the foam exceeds 1000 μm, the pores become too large and the tactile sensation may change partially, which is not preferable.

The pore perimeter of the pores of the foam can be measured by the following method and apparatus.
[Hole perimeter measurement method A]
(1) The foam is cut with a razor to obtain a cross-sectional sample.
(2) Take a photograph of a cross-sectional sample with a system stereomicroscope SZX7 (50x, manufactured by Olympus).
(3) The image of the photographed image is analyzed using image analysis measurement software Win ROOF (manufactured by Mitani Shoji Co., Ltd.), and the perimeter of the pores and the number of pores in a section of a certain size are measured. Confirm the distribution of the hole circumference.

FIG. 1 is a sectional view conceptually showing an example of a preferred embodiment of the foam of the present invention.
As shown in FIG. 1, the foam 1 contains pores of both the first pore 2 having a pore circumference of less than 400 μm and the second pore 3 having a pore circumference of 400 μm or more. It is preferable that
The foam 1 contains two kinds of pores having different sizes of the first pore 2 having a pore circumference length of less than 400 μm and the second pore 3 having a pore circumference length of 400 μm or more. It is possible to improve the texture and touch feeling.
The ratio between the porosity of the first pores 2 having a pore circumference of less than 400 μm and the porosity of the second pores 3 having a pore circumference of 400 μm or more is preferably 1: 0.7 to 1. : 1.5.
When the porosity of the second pore is 0.7 to 1.5 with respect to the porosity 1 of the first pore, the foam 1 is soft and comfortable without impairing the appearance and touch. Tactile feel and texture can be produced.

In the case where the foam contains the first pores having a pore circumference of less than 400 μm and the second pores having a pore circumference of 400 μm or more, the portion containing the second pore is foamed. When the total thickness T _X of the body 1 is 100%, it is preferably in the range of 20% or more, more preferably in the range of 20 to 25% or more from the surface of the foam.
As shown in FIG. 1, when the total thickness T _X of the foam 1 is 100%, the portion (T ₁ ) where the first pores having a pore circumference length of less than 400 μm are present is preferably from the surface. Within a range of less than 20%, more preferably within a range of less than 20-25% from the surface. Also, sites hole perimeter exists second pores than 400 [mu] m _{(T 2)} is preferably in the range from the surface of 20% or more, a range of more than 20-25% from the more preferably the surface.
For example, when the total thickness of the foam is 2 mm, it is preferable that the first pores having a pore circumference length of less than 400 μm are present in a thickness range of less than 0.4 mm from the surface of the foam, It is preferable that the second pores having a pore circumference length of 400 μm or more exist in a thickness range of 0.4 mm or more and 1.6 mm or less.

In the foam 1, there is no large hole having a hole peripheral length of 400 μm or more in a region T ₁ (thickness range of less than 20% from the surface) near the surface, and a relatively small first with a hole peripheral length of less than 400 μm. Due to the presence of one pore 2, the surface of the foam 1 does not look like a crater, and the appearance is not impaired.
In addition, the foam 1 has a relatively large pore 3 having a pore circumference length of 400 μm or more in the range T ₂ (intermediate portion in the thickness direction of the foam) of 20% or more from the surface, A soft touch and a soft texture can be produced.

The foaming ratio of the thermoplastic elastomer constituting the foam of the present invention is preferably 1.7 or more, more preferably 1.7 to 3.0.
The expansion ratio refers to a value obtained by dividing the specific gravity of the unfoamed molded product by the specific gravity obtained from the volume and weight of the foamed molded product (that is, expansion ratio = specific gravity of the unfoamed molded product / specific gravity of the foamed molded product × 100). ).
When the expansion ratio of the thermoplastic elastomer is less than 1.7, it is not preferable because pores having a suitable size in which a soft tactile sensation and a soft texture are felt are not formed, and the tactile sensation and texture may be lowered. Moreover, when the expansion ratio of the thermoplastic elastomer exceeds 3.0, large pores that look like craters are formed on the surface of the foam, which is not preferable.

Further, the foam of the present invention comprises contacting a thickness of the portion contacting the indenter spherical diameter 10mm in 0.5gf / cm ² (T0) the indenter 0.04 mm / sec, at 200 gf / cm ² The amount (T0-TM) of wrinkles represented by a value obtained by subtracting the thickness (TM) of the portion is preferably 0.5 or more, more preferably the amount of wrinkles (T0-TM) is 0.5 to 3.0. Preferably there is.
It is not preferable that the amount of deflection of the foam measured by the above measurement method is less than 0.5, because the feel becomes hard. On the other hand, if the amount of wrinkles exceeds 3.0, for example, the tactile sensation of parts such as an automobile steering, a seat, and an instrumental panel may become too soft, which is not preferable.

Next, the material which comprises the foam of this invention is demonstrated.
As the thermoplastic elastomer constituting the foam of the present invention, a styrene elastomer, an olefin elastomer, a urethane elastomer, an ester elastomer and the like can be used.
Specifically, as a styrene elastomer, a copolymer of polybutadiene and polystyrene or a copolymer of polyisoprene and polystyrene, and as an olefin elastomer, a copolymer of ethylene / propylene / methylene and polypropylene, Examples of urethane elastomers include copolymers of diisocyanates to which short chain glycols are bonded and diisoanates to which long chain polyols are bonded. Examples of ester elastomers include copolymers of polyethylene terephthalate and high molecular weight polyethylene ether glycols. Can be used.

The foaming agent is not particularly limited as long as it is normally used for foam molding of thermoplastic elastomers. For example, foaming composed of general raw materials such as pyrolytic or volatile organic foaming agents and inorganic foaming agents. Agents.
Examples of the pyrolytic organic foaming agent include Cellmic (registered trademark) MB1023 and Cellmic (registered trademark) 1062 manufactured by Sankyo Trio.
Examples of the inorganic foaming agent include Cellmic (registered trademark) 306 and Cellmic (registered trademark) 496 manufactured by Sankyo Trio.
The addition amount of the foaming agent is not particularly limited because it varies depending on the type of the thermoplastic elastomer, but the addition amount of the foaming agent is preferably 1 to 10 weights with respect to 100 parts by weight of the thermoplastic elastomer. Parts, more preferably 3 to 5 parts by weight.

When forming a foam containing a first pore having a pore circumference of less than 400 μm and a second pore having a pore circumference of 400 μm or more, a thermoplastic elastomer is used by using two or more foaming agents. Is preferably foamed.
Two or more kinds of foaming agents may be foaming agents made of the same material and containing two or more kinds of particles having different diameters, and are foaming agents in which particles made of two kinds of materials having different expansion rates are mixed. There may be.

  For the composition containing the thermoplastic elastomer and the foaming agent constituting the foam, various additives, for example, a lubricant, an anti-aging agent, a heat stabilizer, an ultraviolet absorber, a light stabilizer, and copper damage prevention, are necessary. Stabilizers such as agents, antibacterial agents, antifungal agents, dispersants, plasticizers, flame retardants and the like can be included.

A laminated foam obtained by further laminating a layer made of an olefin resin on the foam (foamed layer) of the present invention may be used.
FIG. 2 is a cross-sectional view conceptually showing an example of a preferred embodiment of the laminated foam of the present invention.
As shown in FIG. 2, the laminated foam 10 includes at least second pores 3 having a pore circumference of 400 μm or more, and preferably further includes a first pore 2 having a pore circumference of less than 400 μm. 4 and a resin layer 5 made of an olefin-based resin are laminated.
Examples of the resin layer include polypropylene resin, PC / ABS resin, ABS resin, and nylon resin.
A laminated foam obtained by laminating a foam (foam layer) and a resin layer is obtained by laminating an olefin resin while maintaining excellent tactile sensation with a foam (foam layer) having an appropriate hardness and softness. Maintains the rigidity of the parts.

The ratio of the thickness of the foamed layer 4 and the resin layer 5 of the laminated foam 10 is not particularly limited, but the thickness of the resin layer 5 with respect to the thickness of the foamed layer 4 is 1: 0.5 to 1: It is preferably 3.0.
By making the ratio of the thickness of the foamed layer and the resin layer of the laminated foam within the above range, the rigidity of the component can be more effectively ensured.

Next, the manufacturing method of a foam is demonstrated.
The foam can be manufactured using, for example, a core back type injection molding machine.
When a core back type injection molding machine is used, a thermoplastic elastomer composition containing a foaming agent is injected into the cavity space formed in the mold of the injection molding machine, held for a predetermined time, and then the movable core is The foam can be manufactured by retreating to a predetermined position (distance) at a speed of, and expanding and foaming the cavity space.

  When obtaining a laminated foam obtained by further laminating a layer made of a polyolefin resin on the foam, for example, by using a core back type injection molding machine provided with two injection units by the double injection method, After injecting the olefin-based resin to form the resin layer, the movable core is retracted (primary retract) to inject the thermoplastic elastomer composition containing the foaming agent. Thereafter, the movable core is further retreated (secondary retreat), the cavity space is expanded, and the thermoplastic elastomer composition containing the foaming agent is foamed to produce a laminated foam in which a foam layer is formed on the surface of the resin layer. can do.

The foam and laminated foam of the present invention are excellent in light resistance and heat resistance, have a soft touch that is comfortable to touch, and an excellent appearance, and are interior materials for automobiles, vehicles, ships, buildings, etc. Can be suitably used.
Since the foam and laminated foam of the present invention have moderate hardness and soft touch, interior parts for automobiles such as automobile steering, seats, doors, instrumental panels, assist grips and grips in particular. Can be suitably used.

  EXAMPLES Next, although an Example demonstrates this invention still in detail, this invention is not limited to these Examples.

Example 1
As a thermoplastic elastomer, a foaming agent (foamed styrene # 8331 (trade name)) containing particles having two types of particle sizes with respect to 100 parts by weight of a styrene elastomer (NW241 (trade name), manufactured by Mitsubishi Chemical Corporation). 5 parts by weight) was added to obtain a thermoplastic elastomer composition.
Using this thermoplastic elastomer, a sheet was formed by a core back type injection molding machine (model “MD350S”, manufactured by Ube Industries Co., Ltd.) injecting by a double injection method, and Shore A hardness was measured by JIS K6253. The Shore A hardness was 79.
Polypropylene resin (PM975X (trade name), manufactured by Nippon Polypropylene Co., Ltd.) was used as the olefin resin to be laminated on the sheet (foam).
This polypropylene resin is molded on a thermoplastic elastomer (sheet) under the following molding conditions using a core back type injection molding machine (model "MD350S" manufactured by Ube Industries Co., Ltd.) that injects by the double injection method. A laminated foam composed of a polypropylene resin layer (thickness 2.5 mm) and a foam layer (thickness 4.5 to 6 mm) was produced. The laminated foam of this example is used as automotive parts such as door trims and instrument panels.
The pore perimeter of the pores in the foamed layer obtained by foaming the thermoplastic elastomer, the porosity of the first pores having a pore perimeter of less than 400 μm existing in the foam layer, and the pore perimeter of 400 μm or more The porosity of the second pore was measured by the above-described method and apparatus (pore circumference measurement method A).
Further, the portion where pores having a pore circumference length of 400 μm or more exist in the foam layer has a thickness of 20 to 80% from the surface (100% (6.0 mm) of the total thickness of the foam layer ( The depth was 1.2 to 4.8 mm from the surface.

[Molding conditions]
Gas foaming: ECO
Molding temperature (thermoplastic elastomer (resin) temperature): 210 ° C
Mold temperature: 30 ℃
Holding time: 2 seconds Gas pressure: 0.9 MPa
Core back amount (primary retraction): 1.6 mm
Core back amount (secondary retraction): 2.2 mm

(Example 2)
A laminated foam was produced in the same manner as in Example 1 except that a styrene-based elastomer (NW250 (trade name), manufactured by Mitsubishi Chemical Corporation) was used as the thermoplastic elastomer. The laminated foam of this example is used as automotive parts such as door trims and instrument panels.
The Shore A hardness of the thermoplastic elastomer measured in the same manner as in Example 1 was 66.
Further, the portion where pores having a pore circumference length of 400 μm or more exist in the foam layer has a thickness of 20 to 80% from the surface (100% (6.0 mm) of the total thickness of the foam layer ( The depth was 1.2 to 4.8 mm from the surface.

(Example 3)
A laminated foam was produced in the same manner as in Example 2. The laminated foam of this example is used as automotive parts such as door trims and instrument panels.
Further, the portion where pores having a pore circumference length of 400 μm or more exist in the foam layer has a thickness of 20 to 80% from the surface (100% (6.0 mm) of the total thickness of the foam layer ( The depth was 1.2 to 4.8 mm from the surface.

Example 4
A laminated foam was produced in the same manner as in Example 2 except that a foaming agent composed of particles having one type of particle size (EE405F (trade name), manufactured by Eiwa Kasei Co., Ltd.) was used as the foaming agent. The laminated foam of this example is used as automotive parts such as door trims and instrument panels.
Moreover, the site | part in which the circumference | surroundings length of the hole in a foamed layer has a 400 micrometer or more hole exists 20-80% from the surface with respect to 100% (6.0 mm) of the total thickness of a foamed layer. It was the range of thickness (depth 1.2-4.8mm from the surface).

(Example 5)
A laminated foam was produced in the same manner as in Example 4. The laminated foam of this example is used as an automotive part such as a door thorium or an instrument panel.
Further, the portion where pores having a pore circumference length of 400 μm or more exist in the foam layer has a thickness of 20 to 80% from the surface (100% (6.0 mm) of the total thickness of the foam layer ( The depth was 1.2 to 4.8 mm from the surface.

(Example 6)
A laminated foam was produced in the same manner as in Example 2, except that the secondary back core back amount was 1.6 mm and the foaming ratio of the foamed layer was 1.6. The laminated foam of this example is used as automotive parts such as door trims and instrument panels.
Further, the portion where pores having a pore circumference length of 400 μm or more exist in the foam layer has a thickness of 20 to 80% from the surface (100% (6.0 mm) of the total thickness of the foam layer ( The depth was 1.2 to 4.8 mm from the surface.

(Comparative Example 1)
As a thermoplastic elastomer, it consists of particles having one type of particle size per 100 parts by weight of a styrene elastomer (NW241 (trade name), manufactured by Mitsubishi Chemical Corporation), but a foaming agent (EE405F (trade name) Product) A laminated foam was produced in the same manner as in Example 1 except that 5 parts by weight was added to obtain a thermoplastic elastomer composition.
When the circumference of the pores in the foamed layer obtained by foaming the thermoplastic elastomer was measured in the same manner as in Example 1, no pores with a pore circumference of 400 μm or more were present. Therefore, the ratio of the porosity of the first pores having a pore circumference of less than 400 μm and the porosity of the second pores having a pore circumference of 400 μm or more present in the foamed layer is 1: 0. Met.
In addition, the site | part in which the 1st pore whose hole perimeter length is less than 400 micrometers exists in a foaming layer is 20-90% of thickness from the surface with respect to the total thickness 100 (6.0 mm) of a foaming layer. It was the range (depth 0.6-5.4mm from the surface).

(Comparative Example 2)
A laminated foam was produced in the same manner as in Example 1 except that a styrene elastomer (NW270 (trade name), manufactured by Mitsubishi Chemical Corporation) was used as the thermoplastic elastomer. The Shore A hardness of the thermoplastic elastomer measured in the same manner as in Example 1 was 50.
Further, the portion where pores having a pore circumference length of 400 μm or more exist in the foam layer has a thickness of 20 to 80% from the surface (100% (6.0 mm) of the total thickness of the foam layer ( The depth was 1.2 to 4.8 mm from the surface.

  About the laminated foam of Examples 1-6 and Comparative Examples 1-2, the tactile sensation, light resistance, and heat resistance test were done by the method shown below.

[Tactile measurement method]
<Evaluation sample>
From the laminated foams of Examples 1 to 6 and Comparative Examples 1 and 2, an evaluation sample of 50 mm × 50 mm was produced. This sample was allowed to stand at room temperature (about 23 ° C.) for 48 hours before measurement.
<Measurement device>
The following measuring device was used.
-Equipment: Handy compression tester KES-G5 (manufactured by Kato Tech)
・ Indenter: Spherical jig (diameter 10mm)
<Measurement conditions>
In accordance with JIS Z 8703 (standard state of test place), measurement was performed under the conditions shown in Table 1 below at a standard temperature of 23 ° C. (temperature ± 1 ° C., relative humidity 65 ± 5%) in this standard state.
<Measurement method of amount of wrinkles>
The point where the indenter was brought into contact with the skin of the evaluation sample (the skin on the foam side) at 0.5 gf / cm ² (foam thickness: T0) and the point where the indenter was brought into contact under the conditions shown in Table 1 below (foaming) Body thickness: TM) was measured, and a value obtained by subtracting TM from T0 (T0-TM) was calculated as the amount of wrinkles (tactile sensation). It shows that it is so soft that the amount (T0-TM) of wrinkles is large.

[Method for evaluating light resistance]
<Evaluation sample>
From the laminated foams of Examples 1 to 6 and Comparative Examples 1 and 2, an evaluation sample of 50 mm × 50 mm was produced.
<Measurement device>
The following measuring device was used.
・ Device: Xenon weather meter (manufactured by Suga Test Instruments Co., Ltd.)
-Light source: Xenon arc lamp. As the xenon arc lamp, a water-cooled xenon lamp ranging from a wavelength of 270 nm or less to an ultraviolet, visible and infrared spectrum was used, and the number of lamps was one.
Irradiance meter: An irradiance thermometer conforming to 5.2 of JIS K 7350-1 was used.
The visual double-sided light intensity was 300 to 400 nm.
Black standard thermometer / black panel thermometer: A thermometer conforming to JIS K 7350-1 5.1.5 was used.
<Measurement conditions>
Measurement was performed under the following conditions.
Sample surface light intensity: 162 W / m ²
・ Temperature control: Black panel temperature 89 ± 3 ℃ during irradiation
-Humidity in the tank: 50 ± 5% RH during irradiation
・ Wind speed: about 1m / sec ・ Operation cycle: Continuous irradiation

<Measuring method of difference (ΔE) between after light resistance deterioration and initial stage>
Using the above apparatus, the evaluation sample was allowed to stand for 240 hours under the above conditions, then the evaluation sample was taken out and left at room temperature for 24 hours. Thereafter, the a ₁ value and b ₁ value of the surface of the evaluation sample after light resistance deterioration were measured using the following apparatus.
The a ₀ value and b ₀ value of the surface of the initial (no load) evaluation sample not exposed to the above apparatus and conditions are measured in the same manner, and the numerical values (a ₁ , b ₁ ) of the evaluation sample after light resistance deterioration and the initial values are measured. The difference ΔE (color difference) from the numerical value (a ₀ , b ₀ ) of the evaluation sample was calculated from the following formula (1).
-Colorimeter: SP64 (manufactured by X-Rite)
・ Measurement conditions: D65 / 10 °

<Measuring method of gross change rate after light resistance and initial stage>
An evaluation sample after light resistance deterioration and an initial evaluation sample are prepared using the above-described apparatus and conditions, and the gloss values (a ₁ , b ₁ ) of the evaluation sample after light resistance deterioration and the gloss value of the initial evaluation sample are measured using the following apparatuses. (A ₀ , b ₀ ) was measured, and the gross change rate was calculated from the above equation (1).
・ Gross meter: uni-Gloss 60 (manufactured by Konica Minolta)
・ Measurement conditions: 60 °

[Evaluation method of heat resistance]
The same evaluation sample as the light resistance evaluation method was used as the evaluation sample. This evaluation sample was left in an oven tank (atmosphere temperature; 110 ° C.) for 230 hours, and then the evaluation sample was taken out and left at room temperature for 24 hours. Thereafter, the a ₂ value and b ₂ value of the surface of the evaluation sample after heat deterioration were measured using the following apparatus and conditions.
The a ₀ value and b ₀ value of the surface of the initial (no load) evaluation sample not exposed to the above conditions are measured in the same manner, and the numerical value (a ₂ , b ₂ ) of the evaluation sample after heat resistance deterioration and the initial evaluation sample The difference ΔE (color difference) from the numerical values (a ₀ , b ₀ ) was calculated from the following formula (2).
・ Colorimeter: SP64 (manufactured by X-Rite)
・ Measurement conditions: D65 / 10 °

<Measurement method of gross change rate after heat deterioration and initial stage>
An evaluation sample after heat resistance deterioration and an initial evaluation sample are prepared under the above conditions, and the gloss value (a ₂ , b ₂ ) of the evaluation sample after light resistance deterioration and the gloss value of the initial evaluation sample are prepared according to the following apparatus and conditions. (A ₀ , b ₀ ) was measured, and the gloss change rate was calculated from the above equation (2).
・ Gross meter: uni-Gloss 60 (manufactured by Konica Minolta)
・ Measurement conditions: 60 °

  Conditions such as materials (thermoplastic elastomer, foaming agent), hardness, addition amount of foaming agent, porosity ratio, foaming ratio, and tactile sensation (tawami) Table 2 shows the results of the above measurements on the amount), heat resistance, and light resistance.

As shown in Table 2, the foamed layers of the laminated foams of Examples 1 to 6 have pores with a Shore A hardness of 60 or more and a pore circumference length of 400 μm or more. Excellent with light resistance.
In particular, the foamed layers of the laminated foams of Examples 1 to 3 have the porosity of the first pores having a pore circumference of less than 400 μm and the porosity of the second pores having a pore circumference of 400 μm or more. Is in the range of 1: 0.7 to 1: 1.5, the tactile sensation (T0-TM) is as soft as 0.5 or more, the heat resistance (gloss change rate) is 1.2 or less, and the light resistance ( (Gloss change rate) was excellent at 1.2 or less.
In the foamed layers of the laminated foams of Examples 4 and 5, the ratio between the porosity of the first pores having a pore circumference of less than 400 μm and the porosity of the second pore having a pore circumference of 400 μm or more Was 1: 0.7 or less, specifically 1: 0.4, 1: 0.6, and the tactile sensation (T0-TM) was less than 0.5, which was slightly hard. The heat resistance (gloss change rate) and weather resistance (gloss change rate) of Examples 4 and 5 were slightly higher than those of Examples 1 to 3.
Moreover, since the foaming layer of the laminated foam of Example 6 had a low expansion ratio of 1.6, the tactile sensation (T0-TM) was a hard tactile sensation.
On the other hand, since the foamed layer of the laminated foam of Comparative Example 1 did not contain pores having a pore perimeter of 400 μm or more, the feel (T0-TM) was hard.
Moreover, since the foamed layer of the laminated foam of Comparative Example 2 is foamed with a thermoplastic elastomer having a Shore A hardness of less than 60, the tactile sensation (T0-TM) is as soft as 0.5 or more, but the heat resistance and light resistance It was inferior.
In Examples and Comparative Examples, there was no significant change in the color difference (ΔE) after the initial value and heat resistance deterioration, and after the initial value and light resistance deterioration.

It is explanatory drawing which shows an example of embodiment of the foam of this invention notionally. It is explanatory drawing which shows notionally an example of embodiment of the laminated foam of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Foam 2 1st pore with a hole circumference length of less than 400 μm 3 2nd pore with a pore circumference length of 400 μm or more 4 Foam layer 5 Resin layer 10 Laminated foam T _x Total thickness of foam (foam layer) T sites first pores less than ₁ hole perimeter 400μm exists (thickness or depth)
Site (thickness or depth) where a second pore having a T ₂ pore circumference length of 400 μm or more exists

Claims (8)

  A foam comprising a foamed thermoplastic elastomer having a Shore A hardness of 60 or more, and comprising a plurality of pores having a pore perimeter of 400 μm or more.   A first pore having a pore circumference of less than 400 μm and a second pore having a pore circumference of 400 μm or more, and the porosity of the first pore and the porosity of the second pore; The foam according to claim 1, wherein the ratio is from 1: 0.7 to 1: 1.5.   The foam according to claim 2, wherein the second pores are present in a thickness range of 20% or more from the surface with respect to a total thickness of 100%.   The foam according to any one of claims 1 to 3, wherein the thermoplastic elastomer has a foaming ratio of 1.7 or more. Minus the thickness of the portion contacting the indenter diameter 10mm in 0.5gf / cm ² (T0) from the site in contact the indenter 0.04 mm / sec, at 200 gf / cm ² thick a (TM) The foam according to any one of claims 1 to 4, wherein an amount of warp (T0-TM) represented by a numerical value is 0.5 or more.   Two or more foaming agents are used, The foam according to any one of claims 2 to 5.   A laminated foam comprising a layer made of the foam according to any one of claims 1 to 6 and a layer made of an olefin resin.   An automotive interior part, wherein the foam and / or laminated foam according to any one of claims 1 to 7 is used.

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