JP4858420B2 - Interior material, foam manufacturing method and interior molded product for vehicle - Google Patents

Description

  The present invention relates to an interior material that suppresses generation of crystals in a fogging test, a method for producing a foam, and an interior molded product for a vehicle.

  Conventional interior materials have a fogging problem. Conventionally, there has been no effective means for solving the fogging problem.

  An object of the present invention is to provide an interior material that overcomes the aforementioned problems and suppresses the generation of crystals in a fogging test.

  In order to achieve the above object, the present invention basically comprises the following configuration.

That is, the following (1) and (2).
(1) “A foam that can be obtained by adding 0.1 to 40 parts by weight of a foaming agent and 0.1 to 20 parts by weight of a sulfate with respect to 100 parts by weight of a polyolefin-based resin. The polyolefin resin foam, wherein the sulfate is baked alum and the foaming agent is azodicarbonamide and / or azodicarboxylic acid metal salt.
(2) “Interior material comprising at least a skin material and the polyolefin resin foam according to (1)”.

  According to the present invention, an interior material that suppresses the generation of crystals in a fogging test is produced by containing a fogging inhibitor in at least one of an aggregate material, foam, and interior material foam composed of a skin material, and a skin material. can do.

  Details of the present invention will be described below.

  In the present invention, the fogging inhibitor is added to at least one portion of the interior material having the skin material and / or the foam, and the substance causing the crystal generated from the foam is trapped by the fogging inhibitor. It reduces the crystals generated in the test.

  The fogging inhibitor in the present invention has an ability to trap a substance causing a crystal in a fogging test by chemical reaction or physical adsorption. For example, when the generated crystal is urea, the causative substance is ammonia. In this case, a fogging inhibitor having an ability to trap ammonia can be a fogging inhibitor.

  The fogging inhibitor used in the present invention is preferably a sulfate, more preferably alum, and more preferably baked alum. In addition, porous materials, oxides of transition metal elements such as zinc oxide, and the like are also effective.

  The content is preferably 0.1 to 20 parts by weight, more preferably 1 to 10 parts by weight with respect to 100 parts by weight of the resin, with respect to at least one component of the interior material.

  The method for adding the fogging inhibitor used in the present invention is not particularly limited, but it is preferable to add the fogging inhibitor in pellets containing the fogging inhibitor.

  The interior material in the present invention is an interior material composed of a foam and / or a skin material, or an interior material in which these materials are laminated, or an interior material further having an aggregate, and further, such a laminated interior material is a molded product. What has been done.

  Examples of the foam used in the present invention include polyolefin resin foam.

  Examples of the olefin resin used in the present invention include low density, medium to high density, linear low density polyethylene resins, copolymers of ethylene and vinyl acetate, alkyl acrylate, propylene, and the like. Or a copolymerization polypropylene, a chlorinated polyethylene, etc. are illustrated individually or in mixture.

  The polyolefin resin constituting the foam is particularly preferably a polypropylene resin, containing 1 to 30% by weight of a propylene homopolymer or an α-olefin such as ethylene and butene-1, in a random, random-block or block form. A copolymerized polypropylene resin is preferred. Other resins may be further mixed with these resins as long as the foam is not adversely affected. For example, low density, medium density or high density polyethylene, a polyethylene copolymer copolymerized with α-olefin, or a copolymer with vinyl acetate or acrylate ester containing ethylene as a main component may be mixed.

  The foaming agent is a compound that is liquid or solid at room temperature, and is a compound that decomposes or vaporizes when heated above the melting point of the polypropylene resin, and does not substantially interfere with sheeting or crosslinking reaction. It is preferable that the decomposition temperature is 180 to 240 ° C. Examples of such a pyrolytic foaming agent include azodicarbonamide, azodicarboxylic acid metal salt, dinitrosopentamethylenetetramine and the like. Among these foaming agents, azodicarbonamide is particularly preferable, and is used in the range of 0.1 to 40 parts by weight, more preferably 2 to 25 parts by weight with respect to 100 parts by weight of the resin. The mixing amount can be arbitrarily changed depending on the density.

  As a crosslinking method, a known radiation crosslinking method or a chemical crosslinking method using an organic peroxide can be applied. In order to promote this crosslinking, a polyfunctional monomer such as divinylbenzene or diallyl phthalate can be added.

  Examples of the mixing of the polypropylene resin with the foaming agent and the crosslinking accelerator include a mixing method using a Henschel mixer, a Banbury mixer, a mixing roll, or a mixing method using a kneading extruder. In particular, when the resin is in powder form, powder mixing with a Henschel mixer is convenient. The powder mixing is usually performed between room temperature and the softening temperature of the resin, and the melt mixing is usually performed in the range from the melting temperature of the resin to 195 ° C. In the case of producing a continuous sheet-like foam, it may be formed into a sheet by extrusion molding at a temperature lower than the decomposition temperature of the foaming agent.

  The apparent density of the polypropylene resin foam used in the present invention is preferably 0.025 to 0.200 g / cc. This can be calculated by the apparent density of the foam = {weight of 10 cm × 10 cm × 10 cm} / {volume of 10 cm × 10 cm × 10 cm}. When the apparent density exceeds 0.200 g / cc, the flexibility and feel become poor. When the apparent density is less than 0.025 g / cc, the material strength is weak and air bubble breakage tends to occur.

  The gel fraction of the polypropylene resin foam used in the present invention is preferably 20% or more, more preferably 45 to 60%. If the gel fraction is less than 20%, it is not desirable because the strength of the material is weak at the time of bonding with the foamed sheet and bubble destruction occurs. On the other hand, if the gel fraction exceeds 70%, sufficient foaming cannot be achieved, resulting in poor flexibility and touch.

  In addition, the gel fraction of a polypropylene resin foam is measured as follows.

  First, the foam is cut into about 1 mm square, and about 0.1 g is sampled and precisely weighed as a sample, and its weight is defined as A (g).

  The sample is heated in tetralin for 3 hours at a temperature of 130 ° C., then cooled, further washed with acetone, washed with water to remove the eluate, and then dried. The dried sample is precisely weighed and its weight is defined as B (g).

  The gel fraction (%) is calculated by the following formula.

Gel fraction (%) = (B / A) × 100
The content of the fogging inhibitor is preferably 0.1 to 20 parts by weight and more preferably 1 to 10 parts by weight with respect to 100 parts by weight of the resin with respect to the foam. Although the addition method is not particularly limited, a resin pellet obtained by kneading 10 to 50% by weight (more preferably 20 to 40% by weight) of a fogging inhibitor into a resin is mixed with a foaming resin and a foaming agent or the like. It can be added in the same manner as sometimes.

  Although it does not specifically limit as the skin material of this invention, The fabric-like thing using a natural and artificial fiber, the sheet | seat consisting of a polyvinyl chloride resin, a thermoplastic elastomer sheet, leather, a polyvinyl chloride resin, and ABS resin A known material such as a mixed sheet can be used. Particularly preferable examples include vinyl chloride and thermoplastic elastomer.

  For the skin material, the fogging inhibitor content is preferably 0.1 to 20 parts by weight with respect to 100 parts by weight of the resin, more preferably 1 to 10 parts by weight for the interior skin material, a flame retardant, Coloring agents, antioxidants, fillers, lubricants and the like can be added in appropriate amounts as necessary.

  The aggregate is not particularly limited, but a thermoplastic resin is suitable for application to stamping molding, and a polyolefin resin is preferable. Among them, in consideration of heat resistance and mechanical strength, it is preferable to use polypropylene resin, polypropylene resin in which propylene and α-olefin are copolymerized in random, random-block, block shape, polyethylene resin, or ethylene and α-olefin. And a copolymer resin with vinyl acetate or acrylate, and a resin in which these are arbitrarily mixed can be applied. Furthermore, an inorganic compound such as talc, oxalic acid, calcium carbonate, or the like may be mixed with these resins as a filler as long as the properties as an aggregate resin are not impaired. Moreover, you may add a well-known heat stabilizer, antioxidant, a nucleating agent, a coloring agent, etc. with respect to resin for aggregates as needed. Moreover, you may add resin other than olefins, such as an ABS resin, a polystyrene resin, and a petroleum resin, in the range which does not impair a moldability. A so-called hot stamping mold method that can set the molding pressure smaller than the injection molding is preferable.

In the following examples, alum was added using 30 wt% alum / low density linear polyethylene resin pellets. Further, the salt foaming method was used for all foaming methods.
(Examples 1-5)
80 parts by weight of propylene resin (melt index 2.0), 20 parts by weight of low density polyethylene (density 0.915, melt index 8.0), 15 parts by weight of azodicarbonamide as a foaming agent, and divinylbenzene 4 as a crosslinking aid Part by weight, 0.2 parts by weight of Irgnox 1010 as a stabilizer, and baked alum as a fogging inhibitor are adjusted to 0.1, 0.5, 1.0, 3.0, and 5.0 parts by weight, respectively. -, And the mixture was put into a 90 mmφ single screw extruder (L / D = 25), the average resin temperature was adjusted to 180 ° C., kneaded and extruded, and extruded from a T-die. Five types of crosslinked resin composition foam sheets having a width of 410 mm were molded.

  Next, each foamed resin composition sheet was crosslinked by irradiating with 5 Mrad electron beam using an electron beam irradiator (800 kv) to obtain a crosslinked sheet.

  Next, each crosslinked sheet was heated to about 240 ° C. in a foaming apparatus to produce five types of crosslinked foams.

On one side of the above five types of foam, 100 parts by weight of polyvinyl chloride resin having a polymerization degree of 800 as a skin material, 40 parts by weight of dioctyl phthalate as a plasticizer, and 3 parts by weight of dibutyltin dimaleate as a stabilizer are adjusted. After mixing evenly with a Banbury mixer, a vinyl chloride sheet having a sheet thickness of 0.4 mm is formed by a calender roll method, laminated with a polyester adhesive, and on the other side, a polypropylene resin (melt) melted at 220 ° C. as much as possible. The index = 50) was placed and integrally molded by a hot stamping mold method to obtain five types of molded articles of skin material / foam / aggregate.
(Comparative Example 1)
A composite was molded in exactly the same manner as in Example except that the foam did not contain a fogging inhibitor.

  An interior material composed of an aggregate, a foam, and a skin material was made using the above six types of foams, and the amount of crystals generated was examined by the following fogging test.

(Foging test)
Using a HAAKE fogging apparatus, after heating at 100 ° C. for 3 hours and cooling at room temperature for 1 hour, the presence or absence of crystals was examined. The test was conducted with the vinyl chloride sheet side up. In addition, the fogging inhibitor is not added to the vinyl chloride sheet and the aggregate resin. The presence or absence of crystals was observed with a 50 × optical microscope.

(Examples 6 to 10)
The foam was produced in the same manner as in Comparative Example 1. The skin material bonded to the foam was adjusted to 0.1, 0.5, 1.0, 3.0 and 5.0 parts by weight of baked alum as a fogging inhibitor to 100 parts by weight of polyvinyl chloride resin. Was produced in the same manner as in Comparative Example 1. A composite was formed in the same manner as in Comparative Example 1 using a vinyl chloride sheet containing the five types of fogging inhibitors.

(Comparative Example 2)
A composite was molded in exactly the same manner as in Example except that the skin material did not contain a fogging inhibitor.
(Foging test)
Using a HAAKE fogging apparatus, after heating at 100 ° C. for 3 hours and cooling at room temperature for 1 hour, the presence or absence of crystals was examined. The test was conducted with the vinyl chloride sheet side up. In addition, the fogging inhibitor is not added to the foam and the aggregate resin. The presence or absence of crystals was observed with a 50 × optical microscope.

( Reference Example 1, Examples 12 to 15 )
80 parts by weight of propylene resin (melt index 2.0) obtained by random copolymerization of 4% by weight of ethylene with propylene and 20 parts by weight of low-density polyethylene (density 0.915, melt index 8.0) as azodicarbonamide as a blowing agent 10 parts by weight, 4 parts by weight of divinylbenzene as a crosslinking aid, 0.2 parts by weight of Irgnox 1010 as a heat stabilizer, and 0.1, 0.5, 1.0, 3.0 of baked alum as a fogging inhibitor, respectively. , 5.0 parts by weight, premixed with a Henschel mixer, and the mixture is put into a 90 mmφ single screw extruder (L / D = 25), and the average resin temperature is kept at 180 ° C. or less so as not to decompose the blowing agent. 5 types of foamable resin composition sheets having a thickness of 1.75 mm and a width of 410 mm, respectively, adjusted and kneaded and extruded and extruded from a T-die. Molded.

  Next, each foamable resin composition sheet was crosslinked by irradiating with an electron dose of 5 Mrad using an electron beam irradiator (800 kV) to obtain a foamable resin composition crosslinked sheet.

Next, each foamable resin composition sheet was heated to about 230 to 240 ° C. above the decomposition temperature of the foaming agent in a foaming apparatus to produce a crosslinked foam.
(Comparative Example 3)
A foam was produced in exactly the same manner as in Reference Example 1 except that no fogging inhibitor was contained.

  With respect to the above six types of foams, the amount of crystals generated was examined by the following fogging test.

(Foging test)
Using a HAAKE fogging apparatus, the mixture was heated at 100 ° C. for 3 hours and then cooled at room temperature for 1 hour. The sample was tested by adhering a 0.6 mm vinyl chloride sheet on one side and placing the vinyl chloride sheet side up. The presence or absence of crystals was observed with a 50 × microscope.

(Examples 16 to 18)
80 parts by weight of propylene resin (melt index 2.0) obtained by random copolymerization of 4% by weight of ethylene with propylene and 20 parts by weight of low-density polyethylene (density 0.915, melt index 8.0) as azodicarbonamide as a blowing agent 5 parts, 10 parts and 15 parts by weight, 4 parts by weight of divinylbenzene as a crosslinking aid, 0.2 parts by weight of Irgnox 1010 as a heat stabilizer, and 5.0 parts by weight of baked alum as a fogging inhibitor, Premixed with a mixer, put the mixture into a 90 mmφ single screw extruder (L / D = 25), kneaded and extruded by adjusting the average resin temperature to 180 ° C. or less so as not to decompose the foaming agent, and extruded from a T-die. Three types of foamable resin composition sheets each having a thickness of 1.75 mm and a width of 410 mm were molded.

  Next, each foamable resin composition sheet was crosslinked by irradiating an electron beam irradiator (800 kV with an electron dose of 5 Mrad) to obtain a foamable resin composition crosslinked sheet.

Next, each foamable resin composition sheet was heated to about 230 to 240 ° C. above the decomposition temperature of the foaming agent in a foaming apparatus to produce a crosslinked foam.
(Comparative Examples 4-6)
Foams were produced in exactly the same manner as in Examples 16 to 18 except that no fogging inhibitor was contained.

  The above 6 types of foams were examined for the presence of crystals by the above method.

(Examples 19 to 21)
80 parts by weight of propylene resin (melt index 2.0) obtained by random copolymerization of 4% by weight of ethylene with propylene and 20 parts by weight of low-density polyethylene (density 0.915, melt index 8.0) as azodicarbonamide as a blowing agent 10 parts by weight of each, 4 parts by weight of divinylbenzene as a crosslinking aid, 0.2 parts by weight of Irgnox 1010 as a heat stabilizer, and 5.0 parts by weight of baked alum as a fogging inhibitor, and preliminarily prepared with a Henschel mixer After mixing, the mixture is put into a 90 mmφ single screw extruder (L / D = 25), the average resin temperature is adjusted to 180 ° C. or less so as not to decompose the foaming agent, and the mixture is extruded through a T die, and the thickness is respectively set. A foamable resin composition sheet having a width of 1.75 mm and a width of 410 mm was molded.

  Next, each foamable resin composition sheet was crosslinked by irradiating with an electron beam irradiator (3, 5, 7 Mrad using 800 kV, respectively) to obtain a foamable resin composition crosslinked sheet. .

Next, each foamable resin composition sheet was heated to about 230 to 240 ° C. above the decomposition temperature of the foaming agent in a foaming apparatus to produce a crosslinked foam.
(Comparative Examples 7-9)
Foams were produced in exactly the same manner as in Examples 19 to 21 except that no fogging inhibitor was contained.

  The above six types of foams were examined for the presence of crystals by the above method.

(Examples 22 to 26)
100 parts by weight of a polyvinyl chloride resin having a polymerization degree of 800, 40 parts by weight of dioctyl phthalate as a plasticizer, 3 parts by weight of dibutyltin dimaleate as a stabilizer, 0.1, 0.5, baked alum as a fogging inhibitor After adjusting to 1.0, 3.0, and 5.0 parts by weight and uniformly mixing with a Banbury mixer, five types of sheets having a sheet thickness of 0.4 mm were formed by a calendar roll method.
(Comparative Example 10)
A vinyl chloride sheet was produced in exactly the same manner as in Example 22 except that no fogging inhibitor was contained.

The above six types of sheets were bonded to a polypropylene resin foam having an apparent density of 0.067 g / cm ³ and a heat tetralin extraction residue ratio of 130 ° C. of 57% by using a polyester adhesive to obtain a composite sheet.
(Foging test)
Using a HAAKE fogging apparatus, after heating at 100 ° C. for 3 hours and cooling at room temperature for 1 hour, the presence or absence of crystals was examined. The sample was tested with the vinyl chloride sheet side up. The presence or absence of crystals was observed with a 50 × microscope.

(Examples 27 to 29)
80 parts by weight of propylene resin (melt index 2.0) obtained by random copolymerization of 4% by weight of ethylene with propylene, 20 parts by weight of low density polyethylene (density 0.915, melt index 8.0), and azodicarboxylic as a blowing agent 10 parts by weight of amide, 4 parts by weight of divinylbenzene as a crosslinking aid, 0.2 part by weight of Irgnox 1010 as a stabilizer, and zinc oxide as a fogging inhibitor are 0.1, 0.5, 1.0 and 3.0, respectively. , 5.0 parts by weight, premixed with a Henschel mixer, the mixture is put into a 90 mmφ single screw extruder (L / D = 25), the average resin temperature is adjusted to 180 ° C., kneaded and extruded. Three types of foamed resin composition crosslinked sheets having a thickness of 1.75 mm and a width of 410 mm were formed by extrusion from a die.

  Next, each foamed resin composition sheet was crosslinked by irradiating with 5 Mrad electron beam using an electron beam irradiator (800 kv) to obtain a crosslinked sheet.

Next, each crosslinked sheet was heated to about 230-240 ° C. in a foaming apparatus to produce a crosslinked foam.
(Comparative Example 11)
A composite was molded in exactly the same manner as in Example except that the foam did not contain a fogging inhibitor.

  An interior material composed of an aggregate, a foam, and a skin material was made using the above six types of foams, and the amount of crystals generated was examined by the following fogging test.

(Foging test)
Using a HAAKE fogging apparatus, the mixture was heated at 100 ° C. for 3 hours and then at room temperature. In addition, the fogging inhibitor is not added to the vinyl chloride sheet and the aggregate resin. The presence or absence of crystals was observed with a 50 × optical microscope.

  The present invention relates to an interior material that suppresses generation of crystals in a fogging test, a method for producing a foam, and an interior molded product for a vehicle.

Claims (6)

A foam that can be obtained by containing 0.1 part by weight or more and 40 parts by weight or less of a foaming agent and 0.1 part by weight or more and 20 parts by weight or less of a sulfate with respect to 100 parts by weight of a polyolefin-based resin,
The sulfate is baked alum,
The polyolefin resin foam, wherein the foaming agent is azodicarbonamide and / or a metal salt of azodicarboxylic acid.   The polyolefin resin foam according to claim 1, wherein the polyolefin resin foam is added as a pellet containing baked alum.   The polyolefin resin foam according to claim 1 or 2, wherein the sulfate is 0.5 parts by weight or more and 5 parts by weight or less with respect to 100 parts by weight of the polyolefin resin. Relative to 100 parts by weight of polyolefin resin, wherein the foaming agent is less than 15 parts by weight 5 parts by weight or more, polyolefin resin foam according to any one of claims 1 to 3. The polyolefin resin foam according to claim 1, wherein the polyolefin resin is a polypropylene resin.   An interior material comprising at least a skin material and the polyolefin resin foam according to any one of claims 1 to 5.