JPS58208337A - Composition material for resin molding - Google Patents

Abstract

PURPOSE:To provide a composition material capable of forming resin moldings whose surface can be modified by plasma treatment and which are suitable for use as automobile parts, by mixing polypropylene, high-density polyethylene and EPR or EPT in a specified ratio. CONSTITUTION:The titled composition material is one used for the production of resin moldinqs composed mainly of polypropylene, whose surface is irradiated with plasma under vaccum, coated with urethane paint and baked. The titled material is obtd. by mixing 60-80pts.wt. polypropylene, 10-20pts.wt. ethylene/ propylene rubber or ethylene/propylene/diene rubber and 10-20pts.wt. high- density polyethylene. By using the compsn., resin moldings having good adhesion to coating film can be obtd. by plasma treatment.

Description

[Detailed Description of the Invention] Kipomei is a composition material for resin molded products, in which the surface of a resin molded product whose main component is polypropylene is irradiated with plasma in a vacuum, and a urethane-based paint is applied and baked. It is related to.

For example, automotive parts such as ti pan bars and moldings are made of synthetic fMfW112 whose main component is polypropylene, but since the main component, polypropylene, has crystalline and non-polar properties, it can be directly applied to the surface of the molded product. Even after painting, printing, or adhering other items, the product will peel off. Conventionally, in order to improve the surface, the surface of the resin molded product is steam-cleaned with trichloroethane, etc.
Historically, the practice has been to apply a brimer coat and then apply a topcoat, etc., but not only does the solvent scatter during steam cleaning, damaging the work environment, but also the brimer (secondary base coat) is used in addition to steam cleaning. Painting is required, which is extremely time-consuming, and since chlorinated polypropylene is used as a brimer, it has poor gasoline resistance and is not suitable for automobile parts. (It is also known to irradiate the entire gaseous body with plasma such as oxygen, nitrogen, argon, or helium under vacuum. However, with this plasma treatment, it is not always possible to modify the surface of any resin molded product. First, there are 4EC restrictions on the surface treatment target. purpose.

That is, in the composition material according to the present invention, the main component, polypropylene, is added to 60 to 5 weight parts, ethylene propylene rubber is added to 10 to 20 parts by weight, and high-density polyethylene is added to 10 to 5 parts by weight. It is designed to be mixed in an amount of 20 parts by weight.

This characteristic will be explained below based on experimental data.

Tree inventor! ′: i1 polypropylene (PP), ethylene/
Propylene diene rubber or ethylene propylene rubber (BPR), high density polyethylene (HDPI-i)
were mixed in the proportions shown in Table 1, and samples 1 to 15 of Samurai samples were prepared by Kotoni, which molds automobile bumpers using the respective composition materials. The pp used for the strings was MFI (230°C), 6.
0p/lo minute, EPR is ethylene content 72 4y, MFI + 230℃) 0, 8, ? /]
0 minutes, and as BIDPI3, the density is 0.951. F/memory, MFI (190℃) 0.8,
It is @/10 minutes.

Table 1 Among these samples, samples 6 to 8 have a flexural modulus of 300
oK9At or less, and Sample 11 could not be mixed well with polypropylene, resulting in a beering phenomenon on the surface of the molded product. Historically, Sample 15 had a beering phenomenon and its heat resistance decreased. , not suitable for automobile parts such as bumpers.

Next, each sample (two pairs) was subjected to plasma treatment using a plasma generator as shown in the figure.

The plasma generator has a vacuum pot 1 that houses the object to be processed A, the pressure inside the pot is reduced by a metal pump 2, and air, oxygen, nitrogen, argon gas, etc. are supplied from a gas cylinder 3.

A gas such as helium is passed through the pipe 4 to the plasma generating section 5 (
In the second feed, the waste is made into a plasma state by microwaves from the micro generator 6 and discharged into the pot from the blow-off lower. Inside this device, the external dimensions of the chopsticks are approximately 45+
A bumper formed into a substantially U-shape with an o+ uniform surface was housed as sample A, and plasma treated under the following conditions.

Vacuum pressure crab 0.5 torr Microwave generator 7KW Gas used: Air Gas flow g: 5000 cc, l1j during Th1n processing
l: 60 sec After plasma treatment, the surface of each sample was coated with urethane paint (R
-263, manufactured by Nippon B Chemical Co., Ltd.).
8Q'C An adhesion test was carried out to check for peeling of the coating film by pulling it up at an angle of approximately 90' to the surface. The results are shown in Table 2. In Table 2, "suitability as a single part" is an evaluation of whether the function as a two-part part is significantly impaired or distorted when installed in an automobile.

As can be seen from the results of this trial, from 5 parts by weight of the polypropylene of sample 13, 1 part by weight of ethylene propylene/'rubber, 10 parts by weight of high-strength polyethylene/'10, the polypropylene of sample 14 was 60
Parts by weight, ethylene propylene rubber t; + is the sum of up to 20 parts by weight of ethylene propylene diene rubber and 20 parts by weight of high-density polyethylene Fi! The bumper made of 2cm resin has good paint adhesion and is suitable for use as an automobile part.

According to the composition of the resin molded article according to the present invention as described above, it is possible to obtain a resin molded article which has good coating film adhesion by plasma treatment and is suitable for use as an automobile part.

[Brief explanation of the drawing]

The drawing is a schematic illustration of a plasma generator t that pre-treats the surface of a resin molded product.
：Vacuum pot, 2：Vacuum pump, 3：Gas cylinder, 4：Piping, 5：Plasma generation part, 6：Microwave generator, 7：Discharge row patent applicant Kazuo Takeshita, patent attorney for Hashimoto Formig Industries Co., Ltd. Book by Toshi Nohara
1) Yutaka

Claims (1)

[Claims] A composition material for resin molded products in which the surface of a resin molded product whose main component is polypropylene is irradiated with plasma under vacuum, and then a urethane paint is applied and baked. ! , ethylene propylene rubber mataha ethylene propylene rubber 10 ~
A composition material for a resin molded article, characterized in that 20 parts by weight and 10 to 20 parts by weight of high density polyethylene are mixed.