JPS62294538A - Manufacture of polyurethane foam monolithic molded form - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention [Field of Industrial Application] The polyurethane foam integrally molded product of the present invention is mainly composed of a soft vinyl chloride resin skin and a soft or semi-rigid polyurethane foam, and is used as a crash pad. It is used in automobile interior parts such as instrument panels, armrests, and sun visors.

[Prior art and problems] Polyurethane foam integrally molded products are produced by molding a soft vinyl chloride resin skin obtained by, for example, a powder slush molding method into two metal lower molds, and then molding a foamable mixture consisting of a polyol component and an isocyanate component. It is obtained by a method such as injecting it into the epidermis, tightening the upper mold, and removing the mold after the foaming reaction and urethanization reaction are completed.

Polyurethane foam integrally molded products are mainly used as automobile interior parts. If a car is left in the hot sun for a long time with the windows closed, the surface of crash bats etc. can reach 100 degrees Celsius.
In such cases, the skin material and the urethane foam inside may gradually turn blackish brown.

This tendency is particularly noticeable when the molded article is exposed to temperatures of 110° C. or higher.

In order to solve this problem, there is a method of blending a phosphorus compound into the polyurethane raw material ↑4, which is disclosed in JP-A-60-20
2114, etc.

Although such improvements were effective for a certain amount of time, they were not effective for a long time.

[Constitution of the Invention] The present invention comprises a polyol, a crosslinking agent, a urethanization reaction catalyst,
This is a method for producing an integrally molded polyurethane foam product by injecting a foamable mixture consisting of additives, epoxidized vegetable oil, and an isocyanate component into a skin molded from a chlorine-containing resin.

The polyol component used in the present invention consists of a urethane reaction catalyst, a crosslinking agent, additives, etc. in addition to the polyol. The polyol has a molecular weight of 800 to 12,000.
Polyether polyols such as polyether polyols, polymerizable vinyl monomers such as styrene and acrylonitrile are combined with such polyether polyols, or polymers of these polymerizable monomers or polymer polyols in which organic substances such as polyurea compounds are dispersed are used. .

As the urethanization reaction catalyst, tertiary amine compounds, organic tin compounds, etc. are used.

As the crosslinking agent, diols and triols having a molecular weight of 62 to 500, as well as polyfunctional polyols, diamines, polyamines, etc. are used.

Water, a blowing agent such as trichloromonofluoromethane and methylene chloride, and a flame retardant such as a phosphorus compound are used as the legalizing agent.

As the isocyanate component, tolylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenylisocyanate, chemically modified versions of these polyisocyanates, reactants of these isocyanate compounds with polyols, etc., or these polyisocyanates A mixture of is used.

Polyvinyl chloride as a chlorine-containing resin as a skin material,
Vinyl chloride copolymer, polyvinylidene chloride, chlorinated polyethylene, chlorinated polypropylene, etc. are used.

The epoxidized vegetable oils used in the present invention include epoxidized soybean oil, epoxidized linseed oil, epoxidized cottonseed oil, epoxidized castor oil, and epoxidized rapeseed oil.
Particularly preferred are epoxidized soybean oil, epoxidized linseed oil, and epoxidized rapeseed oil.

These epoxidized vegetable oils are either dissolved in advance in the polyol component or isocyanate component, or added to the reaction system simultaneously with the urethanization reaction.

The amount of epoxidized vegetable oil added is 10% polyurethane foam.
The amount is 1 to 65 parts by weight, preferably 3 to 60 parts by weight relative to 0 parts by weight, and if it is less than 1 part by weight, the effect on heat discoloration of the skin material is insufficient, while if it is 65 parts by weight or more, the effect on preventing heat discoloration of the skin material is insufficient. Although effective, the resulting polyurethane foam tends to shrink.

[Examples and Comparative Examples] Trimethylolpropane added with ethylene oxide and propylene oxide, molecular weight approximately 6000.08, valence 28
mgKOH/3 trifunctional polyether polyol 10
0 parts, 1 part of triethanolamine, ethylene oxide adduct of ethylenediamine (08 value 480 mg KOII
/3) 2 parts, 2.5 parts of water, 0 triethylenediamine
．． Add 5.20.40 parts of epoxidized soybean oil (hereinafter referred to as additive A) to a mixture consisting of 3 parts (equivalent to 3.13.26 parts by weight per 100 parts by weight of polyurethane foam) or The added amount of flaxseed oil (hereinafter referred to as additive B) was changed to 40.70 parts (equivalent to 26.49 parts by weight per 100 parts by weight of polyurethane foam). Screw type stirrer (approx. 200°rpm)
) to form a polyol component.

A PVC skin material molded into the shape of an instrument panel using the powder slush molding method is placed on an aluminum lower mold, and an ABS resin plate is attached to an aluminum upper mold.
Heated to 40-50°C.

Mix polymethylene polyphenylisocyanate and polyol components using a screw type stirrer (approximately 2000 rpm)
After stirring for about IO seconds, the foam was poured into the skin material so that the overall density of the foam was about 0.15 g/d.

After 10 minutes, the mold was removed to obtain a three-layer integral molded product consisting of a polyvinyl chloride skin/polyurethane foam/ABS resin plate. From this integrally molded product, 5cm long, 5cm wide,
A sample containing a 2 cm thick polyvinyl chloride skin and polyurethane foam was cut out and heated in a gear oven at 120°C. After 100 and 200 hours, the sample was taken out of the gear oven and heated using a 5M color computer (manufactured by Suga Test V1). The color difference value (ΔE) of the polyvinyl chloride skin after heating was measured using the color tone before heating as a reference. The results are shown in Table 1.

Comparative examples include a case without adding epoxidized vegetable oil and a case in which a phenol novolac type trifunctional epoxy resin (
20 parts of Sumiepoxy ELM-120 manufactured by Sumitomo Chemical Co., Ltd. (hereinafter referred to as additive C) (10 parts of polyurethane foam)
Add 5 parts (corresponding to 13 parts by weight to 0 parts by weight) or triphenyl phosphite (hereinafter referred to as additive) (corresponding to 3 parts by weight to 100 parts by weight of polyurethane foam), and proceed in the same manner as in the example. An integrally molded product was obtained.

A heating test was conducted on the sample in the same manner as in the example, and the results are shown in Table 2.
Shown below.

Table 1 Table 2 [Effects of the present invention] As is clear from the Examples and Comparative Examples, the integrally molded product made of the polyurethane foam to which epoxidized vegetable oil has been added and the resin containing salt exhibits very little discoloration of the surface upon heating.

that's all.

Claims (1)

[Claims] A method for producing an integrally molded polyurethane foam product by injecting a foamable mixture comprising a polyol, a crosslinking agent, a urethanization reaction catalyst, an additive, an epoxidized vegetable oil, and an isocyanate component into a skin molded from a chlorine-containing resin.