JPS5818932B2 - Method for modifying resin surface - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of metallizing an ABS resin surface.

In contrast to conventional resin metallizing techniques such as metallic painting, hot stamping, and wet plating, metallizing techniques that utilize vacuum technology, which can also be called dry plating, have recently been in the spotlight.

Typical examples of these metallizing techniques include an electron beam method, a high frequency ionization grating method, and a low temperature sputtering method.

In order to attach thin films of various metals or alloys to resin surfaces using these metallizing techniques, the following points are important.

First, to prevent the additives in the resin from gasifying from the resin surface in a high vacuum, and to apply a coating to the shield 2 that improves its adhesion to the resin surface.

For this reason, conventionally, in the case of ABS resin, an acrylic-urethane paint is applied to the surface of the ABS resin by a spraying method, a dipping method, etc., and a hard coating film is formed on the surface of the ABS resin.

This can prevent additives and the like from being gasified from the ABS resin surface, and can further improve adhesion.

Depending on the metal to be metallized, it may be deposited on the ABS resin surface on the aforementioned acrylic-urethane coating film by an electron beam method, high frequency ionization blating method, or low-temperature sputtering method, and then subjected to various environmental conditions, e.g. After a moisture resistance test at 40°C, 90%, etc., coating with the above-mentioned acrylic-urethane paint is currently practiced in order to prevent corrosion.

Therefore, even if the above-mentioned method is used, a technique has been established that causes no problems in terms of coating film performance.

In fact, there were no problems at all in coating film performance tests such as adhesion tests, moisture resistance tests, temperature cycle tests, heat resistance tests, and abrasion tests.

However, although the conventional method has no problems in terms of coating film performance, it has the following drawbacks.

(1) Workability is poor due to the painting process.

(2) Higher costs.

(3) Hair lines, spin, etc. on the resin surface are less likely to appear.

Among these drawbacks, the third one in particular is that it is not simply metallized, and hair lines, spin, etc. on the resin surface are difficult to appear on the metal surface, making it difficult to create a high-class look.

Therefore, for example, in the case of knobs, etc., this method has the disadvantage that it has less merit in terms of commercial value than the conventional wet plating method.

On the other hand, compared to the wet plating method, thin films of various metals or alloys can be attached to the resin surface, which has a significant advantage in terms of metallic color appearance.

As a result of intensive research aimed at solving the above drawbacks, the inventors added 5% by weight or more of one or more metal fine powders selected from brass, copper lead, and gold to ABS resin. At the same time, adhesion is improved by metallizing the surface of the blended thermoplastic resin composition by attaching various types of metals or alloys by electron beam method, high frequency ionization blating method, or low temperature sputtering method. We succeeded in bringing out the spin and hair lines on the surface of ABS resin onto the surface of a thin metal film.

In addition, gas is generated in vacuum from the resin surface because the surface can be hardened by adding at least 5% by weight of fine metal powder, and the thermal conductivity is increased. Since we were able to prevent the surface temperature from becoming extremely high, it was no longer necessary to apply a conventional acrylic-urethane paint.

On the other hand, resins that contain very few substances such as additives that cause gasification in high vacuum, such as U
- The use of a polymer, PBT (polybutylene terephthalate), can also eliminate the need for acrylic-urethane paints, but these resins have the drawback of being extremely expensive.

Furthermore, when fine powders of metals such as brass, copper, lead gold, etc. are added to ABS resin, it is necessary to surface-treat the surfaces of these fine metal powders with higher fatty acids such as stearic acid, oleic acid, and linoleic acid.

Furthermore, unless the amount of metal powder is at least 5% by weight, the surface hardness will not improve and the thermal conductivity will not increase.

In addition, if it exceeds 50% by weight, the fluidity will decrease significantly and the surface of the molded product will not be smooth (after attaching a thin metal film,
The appearance is in poor condition (it is not practical in terms of commercial value).

In particular, metal powders of 25 μm or less have very good dispersibility in ABS resin.

Examples will be described below.

ABS resin (TOYOLAC) 95% by weight Fine metal powder (25μ or less) 5% by weight Stearic acid
Stir and mix at a blending ratio of 1 phr using a tumbler for about 10 minutes.

Thereafter, the mixture is heated and kneaded using an i-axis or twin-screw extruder, and then pelletized using a pelletizer.

A color chip was formed using this pellet, and this plate was used as a sample.

Next, a thin metal film of stainless steel (Sus304) with a thickness of 1000λ or less was deposited using a low-temperature sputtering method, and then an adhesion test and a pencil hardness test were conducted.

The test results are shown in the table below.

Note: Pencil hardness is the pencil hardness of the fabric.

(If there is no metal thin film) As can be seen from the table above, the adhesion was good.

In addition, the surface hardness was HB to 2H from the pencil hardness test, and it was found that the surface hardness was harder than the pencil hardness of the ABS resin fabric.

As described above, according to the method of the present invention, the number of painting steps can be reduced from 2 to 1 compared to the conventional method, resulting in good workability.Moreover, the materials are relatively inexpensive,
Furthermore, hair lines, spin, etc. on the resin surface can be brought out onto the metal film surface.

Claims (1)

[Claims] I ABS resin is blended with 5% by weight or more of one or more metal fine powders selected from copper, lead, and gold, and the surface of the thermoplastic resin composition containing this metal fine powder is coated with electrons. A method for modifying a resin surface, which is characterized by metallizing by depositing various metals or alloys by a beam method, a high-frequency ionization grating method, or a low-temperature sputtering method.