JPH0490340A - Rubber elastomer reinforced resin printed molding excellent in impact resistance - Google Patents

Abstract

PURPOSE:To obtain the title molding excellent in impact resistance by forming a surface layer composed of a thermoplastic resin to a base material part composed of a rubber elastomer reinforced thermoplastic resin and applying printing to the surface of said surface layer part. CONSTITUTION:A rubber elastomer reinforced resin printed molding is obtained by applying printing to the surface of the surface layer part of a laminate wherein a thermoplastic resin layer not containing the rubber elastomer constituting a base material part is laminated to the base material layer composed of a rubber elastomer reinforced thermoplastic resin as a surface layer part in thickness of 0.5-10mum. In this case, when the thickness of the thermoplastic resin layer constituting the surface layer part is below 0.5mum, the effect of a solvent used at the time of printing can not be perfectly prevented and, when said thickness exceeds 10mum, the strength of the impact-resistant resin containing the rubber elastomer is lowered. As the rubber elastomer reinforced thermoplastic resin used in the base material part, there are an impact-resistant acrylic resin, impact-resistant polystyrene, as ABS resin, rubber elastomer-containing polyvinyl chloride resin or a modified polyphenylene ether resin.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a rubber elastic body-reinforced resin printed molded product that does not cause a decrease in impact resistance.

[Conventional technology]

Resins such as acrylic resins and styrene resins have been widely used in automobiles, building materials, electrical and electronic materials, etc. because they have excellent lightness, beauty, printing properties, and various compound properties. Among these uses, for example, lighting covers, vending machine front panels, automobile visors, travel bags, OA equipment housings, tail lamps, signboards, etc., require strong impact resistance, and to meet this demand, various rubber elastic reinforced resins are used. and are used in each field.

Among these uses, there are many molded products that have been printed, and this is actually done by methods such as silk printing. However, there is a problem with these printed rubber elastomer-reinforced resin molded products that printing reduces the inherent impact resistance of the resin, and an effective solution to this problem has not yet been found. This is the actual situation.

[Problem to be solved by the invention]

An object of the present invention is to solve the above-mentioned problems of rubber-elastic-reinforced resin molded products and to provide a printed molded product without impairing the impact resistance inherent in the resin.

[Means to solve the problem]

In order to solve the above problem, the present inventors conducted chain research and found that
The inventors have discovered that the object can be achieved by providing a layer of impact-resistant resin containing the rubber elastic body but not containing the rubber elastic body to a specific thickness on the surface to be printed, and have arrived at the present invention.

That is, in the present invention, a thermoplastic resin layer not containing a rubber elastic body constituting the base material part is laminated as a surface layer on a base material part made of a rubber elastic body reinforced thermoplastic resin with a thickness of 0.5 to 10 μm. The present invention provides a rubber elastic body-reinforced resin printed molded product with excellent impact resistance, which is obtained by printing on the surface layer of a laminate.

The present inventors analyzed the fact that the impact strength of impact-resistant elastic resins containing rubber elastic bodies decreases due to printing, and the rubber elastic bodies in the parts that come in contact with the rubber elastic bodies elute or disintegrate due to the influence of the solvent used during printing. It was discovered that some kind of deterioration occurred in the surface layer, and it was also found that the effect of the solvent was in the very thin layer starting from the surface layer.Based on these findings, the present invention was completed.

Therefore, in the present invention, the thickness of the surface layer, which is affected by the solvent used for printing, is important, and in the present invention, the thickness of the surface layer on the side of the molded product to be printed is 0.5 to 10 μm, preferably 1 μm.
A thermoplastic resin layer that does not contain a rubber elastic body with a diameter of 5 μm or less is required. If the thickness is less than 0.5 μm, the effect of the solvent cannot be completely prevented, and if it exceeds 10 μm, the strength of the impact-resistant resin will decrease due to the thickness of the surface layer that does not contain the rubber elastic body. It's not good to imitate it. The printing referred to in the present invention will mainly be explained with respect to what is obtained by the silk printing method that is commonly used in the market, and is not limited to these methods as long as the technical idea of the present invention is utilized. It also includes various methods such as ink coating, paint coating, and dipping.

In the present invention, the rubber elastic reinforced thermoplastic resin used for the base material includes impact-resistant acrylic resin, impact-resistant polystyrene,
Examples include ABS resin, polyvinyl chloride with rubber elastic material, and modified polyphenylene ether resin.

The rubber elastic bodies used in these thermoplastic resins are elastic bodies that exhibit a rubber-like state at room temperature, such as rubber-like polymers containing butadiene as a main component, acrylic acid ester polymers, and ethylene-vinyl acetate copolymers. A rubber-like elastic body, etc.

Specific examples of rubber-like polymers containing butadiene as a main component include butadiene homopolymers, copolymers of butadiene and aromatic vinyl monomers in various compositions, and acrylic acid ester polymers. Specific examples include those whose main components are butyl acrylate, 2-ethylhexyl acrylate, etc. Typical examples include alkyl acrylate such as butyl acrylate, a grafted rubber elastic component of styrene, and methyl methacrylate and/or methyl methacrylate. There are hard resin layers made of a copolymer of and alkyl acrylate, and particulate elastic bodies that form multilayers with a core-shell structure.

In addition, from the viewpoint of adhesion to the base material, is it preferable that the thermoplastic resin that does not contain a rubber elastic body used for the surface layer part in the present invention be the same thermoplastic resin as the thermoplastic resin used for the base material part?
The thermoplastic resin may be different from the thermoplastic resin used for the base material if there is no problem with adhesion.

Specifically, alkyl methacrylates, homopolymers of alkyl acrylates, copolymers thereof, and combinations of these monomers with aromatic vinyl compounds such as styrene, unsaturated carboxylic acids such as acrylic acid, methacrylic acid, and maleic anhydride. Copolymers with monomers selected from acids and unsaturated dicarboxylic acid anhydrides, and those having six-membered cyclic acid anhydride units and six-membered cyclic imide units derived from carboxylic acids in the molecule, and polystyrene. Resins, styrene, acrylonitrile copolymer (AS resin), styrene, acrylonitrile, butadiene copolymer (ABS resin), polyvinyl chloride resin, compounds of polyphenylene ether resin and styrene resin, etc. can be used.

In the present invention, a molded product having a surface layer on one or both sides can be produced by coextrusion, coating, film lamination, etc. However, due to the thin film thickness of the surface layer, coextrusion and coating are preferred. preferable. In the co-extrusion method, two or more extruders are used. In the present invention, one extruder produces the rubber elastic body-reinforced thermoplastic resin as the base material, and the other extruder produces the rubber elastic body as the surface layer part. The amount of extrusion into the surface layer is very small compared to the amount of extrusion into the base material section because the thickness of the surface layer is thinner.

The thickness of the surface layer and base material of the laminated sheet and the thickness of the molded product can be controlled by the extrusion rate of two or more extruders and the roll clearance of the polishing roll at the exit of the extruder.

Furthermore, when creating a laminated sheet, it is important to match the fluidity of the resins in the base and surface layers, and this can be done by specifically adjusting the temperature of the extruder.

The thickness of the surface layer of the laminated sheet can be evaluated by observing the tomographic plane with a transmission electron microscope.

Furthermore, in the coating method, the thermoplastic resin used for the surface layer is dissolved in an appropriate solvent and coated on the thermoplastic resin containing the rubber elastic body of the base material, and then the solvent is evaporated. .

The present invention relates to a rubber elastomer-reinforced resin printed molded product with excellent impact resistance, which is obtained by printing on the surface layer of a laminated molded product laminated by the method described above.

The laminate molded product can be made into a transparent, translucent or opaque sheet by blending organic or inorganic dyes or pigments into the surface layer and/or base material. In addition, various light stabilizers, anti-oxidant ultraviolet absorbers, etc. can be added.

Furthermore, it is also possible to add antistatic properties to the final product by adding a commercially available antistatic agent to the surface layer. A plasticizer may also be added to the base material.

〔Example〕

The present invention will be specifically explained below using Examples and Comparative Examples.

The evaluation and test methods used in each Example and Comparative Example are as follows.

(1) Impact resistance evaluation: A falling ball impact test was adopted, and the equipment was a DuPont impact tester manufactured by Toyo Seiki Seisakusho. Drop it towards the opposite side, and the 50 out of 12 tests
The impact strength was determined from the height at which % or more of the sample broke, and was defined as the impact strength of the sample.

(2) Evaluation of adhesion of laminated surfaces: A heat cycle test was conducted at 60°C and -30°C for 3 hours each, and adhesion was determined from the change in appearance of the sample after 30 cycles.

Example 1 Comparative Example 1 Asahi Kasei Delpet LP-1 as the thermoplastic resin for the surface layer
(copolymer of methyl methacrylate and methyl acrylate) using an extruder with a diameter of 20 mm and L/D = 24,
In addition, Asahi Kasei Delpet S R-8350 (an acrylic acid ester elastomer mainly composed of butyl acrylate is dispersed in a continuous phase consisting of a copolymer of methyl methacrylate and methyl acrylate) is used as the rubber elastic body-reinforced thermoplastic resin for the base material. diameter 60mm, L/
Coextrusion was carried out using a D=32 extruder.

Die is 2 types, 2 layers feed block type, lip opening is 4m
m, and the extruder temperature was 250-260°C.

The thickness of the laminate was adjusted to three targets in order by adjusting the clearance of the polishing roll at the exit of the die, and the thickness of the surface layer was adjusted by adjusting the discharge rate of the extruder. Although a sheet with a sheet width of 60 cm was produced in this way, the thickness of the center portion of the base portion and surface layer portion was 3.0 mm and 2.0 mm, respectively.
(The thickness of the surface layer was measured by observing the tomographic plane of the sheet with a transmission electron microscope). The impact strength of this sample was evaluated using the method described above and was found to be 38 kg-cm in terms of DuPont impact strength. ■ Seiko Advance's white silk screen ink (#2500) was applied to the surface layer of this laminate using solvent F25.
Silk printing was performed using the material dissolved in 00, and after one day had passed after drying, the DuPont impact test was performed in the same manner as above, and the result was that the impact strength was 37 kg-cm, which is almost the same strength as that without printing. Indicated. Further, as a result of conducting an adhesion test using the method described above, there was no problem in adhesion for both the printed and unprinted laminates.

Delpet SR used for the base material part of Example 1 for comparison
8350 alone can produce a 3-thick single layer sheet with the same diameter of 60m.
When a DuPont impact test was performed on this product and another product that was silk-printed in the same manner as in Example 1 and dried for one day, the impact strength was 40 kg-an for the former and 40 kg-an for the latter. The weight was 18 kg-an, and the impact strength was significantly reduced at the point of printing.

Examples 2 to 6, Comparative Examples 2 to 4 Laminate samples with various thicknesses of the surface layer were prepared in the same manner as in Example 1, and silk printing was performed on the surface layer in the same manner as in Example 1. DuPont impact strength and adhesion were evaluated. The results are shown in Table-1.

Table 1 (Soujita Nairaku) [Effects of the Invention] Rubber elastomer-reinforced resin molded products had the disadvantage that their impact resistance was significantly reduced by printing.

The present invention has succeeded in solving this problem and providing the molded article that can be printed without reducing impact resistance.

Patent applicant: Asahi Kasei Industries, Ltd.

Claims (1)

[Claims] 1. A laminate in which a thermoplastic resin layer not containing a rubber elastic body constituting the base material portion is laminated as a surface layer on a base material portion made of a rubber elastic body-reinforced thermoplastic resin with a thickness of 0.5 to 10 μm. An impact-resistant printed molded product with printing applied to the surface layer.