JP2005119081A - Manufacturing method for thermoplastic resin molded product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a thermoplastic resin molded product low in cost and having good recyclability capable of enhancing the adhesion of a weatherable resin to an alloyed resin in a low temperature region. <P>SOLUTION: This thermoplastic resin molded product 4 is manufactured by applying the weatherable resin 2 to the surface of an alloyed resin formed product 1 wherein a polyethylene terephthalate (PET) resin 1a and an ABS resin 1b are alloyed. In applying the weatherable resin 2 to the surface of the alloyed resin formed product 1, the ABS resin 1b in the vicinity of the surface of the alloyed resin formed product 1 is removed by chemically etching the surface of the alloyed resin formed product 1 and the surface of the alloyed resin formed product 1 is subsequently coated with the weatherable resin 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for producing a thermoplastic synthetic resin molded article in which a weather resistant resin is coated on the surface of an alloyed resin molded article obtained by alloying a polyethylene terephthalate (PET) resin and an ABS resin.

Conventionally, what makes a polyethylene terephthalate (PET) resin and an ABS resin alloy is known. (For example, see Patent Document 1)
Polyethylene terephthalate (PET) resin and ABS resin are alloyed to provide high strength and heat resistance due to stretch molding, which is a characteristic of polyethylene terephthalate resin, and impact resistance and adhesion between ABS resin and other resins Can be obtained. However, weather resistance becomes a problem when using the alloyed resin molded product outdoors.

  Here, the weather resistance is improved by covering the surface with a weather resistant resin such as an acrylic resin having excellent weather resistance after the alloyed resin is stretch-molded.

  When the weathered resin excellent in weather resistance is coated with good adhesion after the alloyed resin is stretch-molded, the alloyed resin is heated to a temperature close to the melting point to melt the ABS resin component and the highly weatherable weatherable resin. There is a need to wear it, or a film is laminated through an adhesive layer, or a weather-resistant paint such as acrylic is applied.

  However, when the alloyed resin is heated to a temperature close to the melting point, and the ABS resin component and the weather resistant resin having high weather resistance are fused, the alloyed resin is heated to a temperature close to the melting point (that is, the temperature is increased). There is a problem that the crystallinity of PET is increased and impact resistance is lowered, and those that are coated with a weather-resistant resin by providing an adhesive layer and those that are coated with a weather-resistant paint are more Although it becomes possible to coat the alloyed resin with a weather-resistant resin at a low temperature, there are problems with the cost of the adhesive and the recyclability after the multilayering.

Further, Patent Document 2 discloses that the surface of a molded product molded with a resin composition in which an ABS resin is blended with a PET resin is roughened with an acidic liquid, then roughened with an alkaline liquid, and then the rough surface is plated. However, when the surface of an alloyed resin molded product obtained by alloying a PET resin and an ABS resin is coated with a weather resistant resin, the surface of the alloyed resin molded product is subjected to chemical etching to remove the ABS resin content near the surface. It has not been known yet to remove and then coat the surface of the alloyed resin molded article with a weather resistant resin.
JP 2003-128905 A JP-A-6-88245

  The present invention has been invented in view of the above-described conventional problems, and is a thermoplastic resin that is low in cost, has good recyclability, and can enhance the adhesion of the weather resistant resin to the alloyed resin in a low temperature range. It is an object of the present invention to provide a method for producing a molded product.

  In order to solve the above-mentioned problems, a method for producing a thermoplastic resin molded product according to the present invention includes a weather resistant resin 2 on the surface of an alloyed resin molded product 1 obtained by alloying a polyethylene terephthalate (PET) resin 1a and an ABS resin 1b. In manufacturing the coated thermoplastic resin molded article 4, the surface of the alloyed resin molded article 1 is chemically etched to remove the ABS resin 1b near the surface, and then the weathered resin is applied to the surface of the alloyed resin molded article 1 2 is covered.

  By adopting such a method, the surface of the alloyed resin molded product 1 is made uneven by chemically etching the ABS resin 1b near the surface of the alloyed resin molded product 1 before coating with the weather resistant resin 2. The adhesion of the weather resistant resin 2 to the alloyed resin molded article 1 is improved by the anchor effect by the weather resistant resin 2 entering the uneven portion 3 on the surface thus formed. Since the adhesive resin 2 and the ABS resin 1b do not need to be fused, they can be coated without lowering the impact resistance in a low temperature range, and further, since no adhesive layer is provided, the cost is low and the recyclability is improved. Is.

  Moreover, after chemically etching the surface of the alloyed resin molded article 1, it is preferable to perform corona discharge treatment or plasma discharge treatment, and then coat the weather resistant resin 2.

  By adopting such a method, the wettability of the concavo-convex portion 3 on the surface of the alloyed resin molded article 1 after chemical etching is improved, and the weather resistant resin 2 is more easily penetrated into the concavo-convex portion 3, In addition, the adhesion can be improved. In particular, the corona discharge treatment is effective as a means for improving the wettability of the surface of the alloyed resin molded product 1.

  The weather resistant resin 2 is preferably made of an ASA resin or an acrylic resin, and the chemical etching agent is preferably methyl ethyl ketone, xylene, or a chlorine solvent.

  In the present invention, as described above, the ABS resin component in the vicinity of the surface of the alloyed resin molded product is chemically etched to form an uneven shape on the surface of the alloyed resin molded product before coating with the weather resistant resin. As the weather resistant resin enters the uneven surface of the surface, the adhesion of the weather resistant resin to the alloyed resin is improved by the anchor effect, and it is necessary to fuse the weather resistant resin and the ABS resin as before Therefore, it is possible to cover the alloyed resin molded product with a weather resistant resin so that the impact resistance is not lowered in a low temperature range, and further, since an adhesive layer is not provided, the cost is low and the recyclability is improved. .

  Hereinafter, the present invention will be described based on embodiments shown in the accompanying drawings.

  In the present invention, a thermoplastic resin molded article 4 in which a weather resistant resin 2 is coated on the surface of an alloyed resin molded article 1 obtained by alloying a polyethylene terephthalate (PET) resin 1a and an ABS resin 1b is manufactured. Here, the alloyed resin molded product 1 obtained by molding an alloyed resin obtained by alloying the PET resin 1a and the ABS resin 1b has the characteristics of the PET resin 1a, such as high strength and heat resistance, impact resistance by the ABS resin 1b, and other properties. Although adhesion to the resin can be obtained, the PET resin 1a has a problem in weather resistance. Therefore, in the present invention, the weather resistance is improved by coating the surface of the alloyed resin molded article 1 with the weather resistant resin 2 as described above.

  In order to mold the alloyed resin molded article 1 with an alloyed resin obtained by alloying the PET resin 1a and the ABS resin 1b, the molding is performed as follows.

  First, the alloying of the PET resin 1a and the ABS resin 1b is performed by melt-kneading the PET resin 1a and the ABS resin 1b. An olefinic compound containing a carboxylic anhydride group at the time of the melt-kneading, A compatibilizer such as a styrene-based olefin compound or an epoxy-modified olefin compound is blended and dispersed uniformly. Next, this is melted, mixed and extruded by a twin screw extruder, and after cooling the extruded product, it is cut into a few millimeters by a pelletizer and alloyed resin pellets of PET resin 1a and ABS resin 1b. Form.

  Next, by using the alloy resin pellets of the PET resin 1a and ABS resin 1b obtained as described above, extrusion molding is performed by an extruder, the extruded product is rolled and rolled between rolls, and further heated. The alloyed resin molded product 1 is molded by orientation and crystallization.

  The weather resistant resin 2 is coated on the surface of the alloyed resin molded article 1 obtained by alloying the PET resin 1a and the ABS resin 1b obtained as described above. The surface of the alloyed resin molded article 1 is coated with the weather resistant resin 2 as follows.

  That is, the surface of the alloyed resin molded product 1 obtained by the above-described process is chemically etched to remove the surface of the alloyed resin molded product 1 obtained by alloying the PET resin 1a and the ABS resin 1b. . The chemical etching agent may be any solvent that dissolves the ABS resin 1b and does not dissolve the PET resin 1a. However, it is effective to use a chlorine-based solvent such as methyl ethyl ketone, toluene, xylene, or chloroform.

  Next, the weather resistant resin 2 is coated on the surface of the alloyed resin molded product 1 whose surface has been made uneven by chemical etching. As a result, the weather resistant resin enters the concavo-convex portion 3 of the surface formed by removing the ABS resin 1b in the vicinity of the surface of the alloyed resin molded product 1 by chemical etching, and the weather resistant resin 2 is formed by a so-called anchor effect. It adheres firmly to the alloyed resin molded product 1.

  Thus, in the present invention, since it is not necessary to fuse the weather resistant resin and the ABS resin 1b as in the prior art, it can be coated so that the impact resistance does not decrease in the low temperature range, and the adhesive layer Therefore, recyclability is improved at low cost.

  In addition, as resin excellent in the weather resistance used by this invention, it is resin which can endure the use use outdoors, for example, acrylonitrile styrene acrylic rubber (ASA) resin, acrylonitrile styrene copolymer (AS ) Resins, acrylonitrile acrylic rubber styrene copolymer (AAS) resins, acrylonitrile ethylene propylene rubber styrene copolymer (AES) resins, and polymethyl methacrylate (PMMA) resins.

  Further, in the present invention, as described above, the surface of the alloyed resin molded product 1 is chemically etched, and then the alloyed resin molded product is intended to improve the wettability of the uneven portion 3 on the surface of the alloyed resin molded product 1. The surface of the product 1 may be subjected to corona discharge treatment or plasma discharge treatment, and then the weather resistant resin 2 may be coated. After chemical edging in this manner, corona discharge or plasma discharge treatment is performed to improve the wettability of the concavo-convex portion 3 so that the weather-resistant resin 2 can more easily enter the concavo-convex portion 3 and the weather-resistant resin 2 The adhesion to the surface of the alloyed resin molded product 1 will be further improved. In particular, the corona discharge treatment is effective as a means for improving the wettability of the surface of the alloyed resin molded product 1.

  FIG. 1 shows an example of the order in which the surface of the alloyed resin molded article 1 is coated with the weather resistant resin 2 in the present invention as described above. 1A shows an alloyed resin molded article 1 obtained by alloying PET resin 1a and ABS resin 1b, FIG. 1B shows a state where the surface of the alloyed resin molded article 1 is chemically etched, and FIG. Shows the state where the surface has been further subjected to corona discharge treatment after chemical etching (the wettability of the dotted portion of the surface has been improved by corona discharge treatment), and (d) shows the state after which the weather resistant resin 2 has been coated. ing.

  Next, examples of the present invention will be specifically described.

(Example 1)
30 parts by weight of ABS resin 1b (“Toyolac 600” manufactured by Toray Industries, Inc.) is blended with 70 parts by weight of PET resin 1a (“NES2070” manufactured by Unitika). 3 parts by mass of a compatibilizer (epoxy-modified polystyrene resin) was blended and dispersed uniformly, and then melted and mixed by a twin-screw extruder and extruded into a 2 mmφ cylindrical shape. The extruded product was cooled and then cut into a length of 2 mm with a pelletizer to obtain alloyed resin pellets of PET resin 1a and ABS resin 1b.

  Next, using the alloy resin pellets of the PET resin 1a and the ABS resin 1b obtained as described above, extrusion molding is performed by an extruder, and the extruded product is stretched three times by rolling between two rolls. By heating at 160 ° C. for 5 minutes, orientation and crystallization were performed to form an alloyed resin molded product 1 which is a stretch molded product.

  The alloyed resin molded product 1 as this stretched molded product was immersed in methyl ethyl ketone as a chemical etching agent at room temperature for 2 minutes.

  Thereafter, the surface of the alloyed resin molded product 1 was further subjected to corona discharge treatment. In the corona discharge treatment, the corona discharge treatment was performed at an output of 14 kV using a corona discharge treatment apparatus (Corona Master PS-1M) manufactured by Shinko Electric Measurement Co., Ltd. At this time, when the wettability of the surface of the alloyed resin molded product 1 which is the corresponding stretched molded product was measured according to the wetting test method of JIS K6768, the wetting index was improved from 31 dyne / cm to 73 dyne / cm.

  Next, an ASA resin (“Vitax V6700” manufactured by Hitachi Chemical Co., Ltd.) was coated on the surface of the alloyed resin molded article 1 at a temperature of 160 ° C. using a multi-layer extrusion mold.

(Example 2)
An alloyed resin pellet of PET resin 1a and ABS resin 1b is prepared in the same manner except that the corona discharge treatment is not applied to Example 1, and then extrusion molding, stretch molding, and multilayer molding are performed. 2 was produced.

(Comparative example)
In the same manner as in Example 1 except that chemical etching and corona discharge treatment are not performed, alloyed resin pellets of PET resin 1a and ABS resin 1b are produced, and extrusion molding, stretch molding, and multilayer molding are performed. Comparative examples were prepared.

  The adhesion between the alloyed resin molded article 1 and the ASA resin, which is the coated weather resistant resin 2, was evaluated by a cross-cut adhesion test (JIS K5400).

Evaluation result-Example 1: Number of peeling 0 (0/100)
-Example 2: Number of peeling 20 (20/100)
Comparative example: number of peels 80 (80/100)
As is apparent from the above evaluation results, it was found that the adhesives of Examples 1 and 2 were superior in adhesion compared to the comparative example, and in particular, the corona discharge treatment was performed after chemical etching. It was found that the adhesion between the alloyed resin molded article 1 and the ASA resin as the coated weather resistant resin 2 was dramatically improved in Example 1 compared to the comparative example.

It is explanatory drawing which shows the order which coat | covers a weather resistant resin on the surface of an alloyed resin molded product in this invention.

Explanation of symbols

1 Alloyed resin molded product 2 Weather-resistant resin 3 Concave and convex portions

Claims (4)

  In manufacturing a thermoplastic resin molded article in which the surface of an alloyed resin molded article obtained by alloying a polyethylene terephthalate resin and an ABS resin is coated with a weather resistant resin, the surface of the alloyed resin molded article is subjected to chemical etching and ABS in the vicinity of the surface. A method for producing a thermoplastic resin molded article, wherein the resin component is removed, and then the surface of the alloyed resin molded article is coated with a weather resistant resin.   2. The heat according to claim 1, wherein the surface of the alloyed resin molded article is chemically etched, then subjected to corona discharge treatment or plasma discharge treatment, and then the surface of the alloyed resin molded article is coated with a weather resistant resin. A method for producing a plastic resin molded article.   The method for producing a thermoplastic resin molded article according to claim 1 or 2, wherein the weather-resistant resin comprises an ASA resin or an acrylic resin. The method for producing a thermoplastic resin molded article according to any one of claims 1 to 3, wherein the chemical etching agent is methyl ethyl ketone, xylene, or a chlorine-based solvent.

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