JPH06279602A - Polyolefin resin molded product capable of being plated in electroless state - Google Patents

Abstract

PURPOSE:To provide the subject molded product capable of exhibiting an electromagnetic shielding effect and having an electrolessly plated coating film at a low cost by applying a specific treatment onto the surface of a molded product containing a polyolefin and an acid-soluble inorganic substance. CONSTITUTION:The surface of a molded product comprising a resin composition comprising 50-90wt.% of a polyolefin resin (e.g. ethylene polymer, propylene polymer) and 50-10wt.% of an acid-soluble inorganic substance (preferably calcium carbonate) is successively subjected to treatments consisting of (1) the removal of a skin layer (20-90wt.% of a dichromate, etc. for 1-20min), (2) the etching treatment of the surface of the molded product with an acid (preferably 20-90wt.% of hydrochloric acid, etc., for 1-20 min) to form anchor holes, (3) the formation of anchor holes (preferably 1-20wt.% of a polymer amine, etc., for 30-40 deg.C for 1-5min), (4) the adsorption of catalyst particles (preferably stannous chloride, etc., at 20-60 deg.C for 1-10min), etc., to provide the objective molded product.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel electroless-platable polyolefin resin molding, and more specifically, it is capable of electroless plating and retains the excellent physical properties of polyolefin even after plating. The present invention relates to a polyolefin resin molded product that can exhibit an electromagnetic wave shielding effect at low cost.

[0002]

2. Description of the Related Art In recent years, the electromagnetic wave shield (EMI shield) of resin products has become an important resin with the increasing use of electronic control equipment. Various methods have been known so far for the EMI shielding technology for resin products, and for example, a method of using a conductive polymer and a method of filling a conductive metal filler have been tried.

However, the method using a conductive polymer is inevitably high in cost at the present stage and cannot be applied to general industrial parts. In addition, the method of filling with a conductive metal filler has drawbacks such as poor appearance of the molded product, deterioration of physical properties, and high cost, and its use is substantially limited.

On the other hand, by plating the surface of the product,
Although a method of producing a shielding effect has been proposed, the resin that can be plated is limited, and this method has a drawback that it cannot be applied to a resin that cannot be plated, such as polyolefin.

Therefore, heat resistance, moldability, chemical resistance,
There has been a strong demand for the development of a technique that enables plating without impairing the characteristics of polyolefin having excellent impact resistance.

[0006]

The present invention meets the above-mentioned demands, and is capable of electroless plating. It retains the excellent physical properties of polyolefin even after plating and, at the same time, provides an electromagnetic wave shielding effect at low cost. The purpose of the present invention is to provide a polyolefin resin molding capable of exhibiting electroless plating.

[0007]

Means for Solving the Problems As a result of intensive studies to develop a polyolefin resin molded body capable of electroless plating, the present inventors have found that in a molded body obtained by adding an acid-soluble inorganic substance to polyolefin. It has been found that electroless plating is possible by subjecting the surface to a specific treatment. Further, in order to impart various mechanical properties, an inorganic substance or an elastomer insoluble in acid is further added to this molded body,
It has been found that those whose surface has been subjected to a predetermined treatment maintain a wide range of mechanical properties and are capable of electroless plating. The present invention has been completed based on such findings.

That is, according to the present invention, (A) 50-90% by weight of a polyolefin resin and (B) an acid-soluble inorganic substance 5
0 to 10% by weight of a resin composition, or, if desired, at least 1 selected from among (C) acid-insoluble inorganic substances and elastomers in an amount of 70 parts by weight or less per 100 parts by weight thereof. (A) Treatment to remove the skin layer on the surface of the molded product made of the resin composition containing the seed, (b) Treatment to etch the inorganic substance on the surface with an acid to form an anchor hole, and (c) Give polarity. Processing, and (d)
It is intended to provide a polyolefin resin molding capable of electroless plating, which is characterized in that treatments for adsorbing catalyst particles are sequentially performed.

There is no particular limitation on the polyolefin resin used as the component (A) in the present invention. For example, ethylene, propylene, butene-1,3-methylbutene-1,3-methylpentene-1,4-methylpentene-1. Examples include α-olefin homopolymers and copolymers thereof, and copolymers of these with other copolymerizable unsaturated monomers. Typical examples are high-density, medium-density, low-density polyethylene, linear low-density polyethylene, ultra-high-molecular-weight polyethylene, polyethylenes such as ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and propylene alone. Polymers, propylene-ethylene block copolymers, random copolymers, polypropylenes such as propylene-ethylene-diene compound copolymers, polybutene-1, poly-4-methylpentene-1, etc. Among them, a propylene homopolymer and a crystalline propylene-ethylene copolymer having a melt index in the range of 0.1 to 100 g / 10 min are particularly preferable.

These polyolefin resins may be used alone or in combination of two or more, and the compounding amount thereof is 50 based on the total weight of the component (A) and the component (B). It is necessary to be in the range of up to 90% by weight. If this amount is less than 50% by weight, the specific gravity of the obtained molded article increases, the impact resistance decreases, the surface appearance becomes poor, and the adhesion strength of the plating decreases.
When it exceeds 0% by weight, rigidity and heat resistance are deteriorated, and further, etching property and adhesion strength of plating are deteriorated.

There is no particular limitation on the acid-soluble inorganic substance used as the component (B) in the present invention. For example, calcium carbonate, basic magnesium oxysulfate, magnesium carbonate, dolomite, dawsonite,
Examples thereof include magnesium hydroxide, and among these, calcium carbonate and basic magnesium oxysulfate are particularly preferable.

These acid-soluble inorganic substances may be used alone or in combination of two or more, and the compounding amount thereof is the total weight of the component (A) and the component (B). It is necessary to be in the range of 50 to 10% by weight. If this amount is less than 10% by weight, anchor holes cannot be sufficiently formed, the adhesion of the plating is reduced, and defective products are generated in a heat cycle test or the like. Is too rough, the adhesion of the plating is reduced, and the specific gravity of the resulting molded article is increased, and the impact resistance is also reduced.

In the present invention, a resin composition comprising the above-mentioned component (A) and component (B) may be used, but in order to impart various mechanical properties, the resin composition (A) may be added as desired. A resin composition in which 70 parts by weight or less of at least one selected from (C) an acid-insoluble inorganic substance and an elastomer is mixed with 100 parts by weight of a mixture of the component and the component (B). You may use.

The inorganic substance insoluble in the acid is not particularly limited, and examples thereof include talc, sericite, mica, clay, glass fiber, wollastonite, potassium titanate fiber, calcium silicate fiber and gypsum fiber. . These may be used alone or in combination of two or more.

The elastomer is not particularly limited, and an elastomer usually blended with a polyolefin such as EPDM, or an elastomer composed of a hard segment such as polypropylene or polyethylene and a soft segment such as EPDM is used. be able to. These elastomers may be used alone or in combination of two or more kinds, and one or more kinds of this elastomer and one or more kinds of the above-mentioned acid-insoluble inorganic substance may be used in combination. .

In the resin composition of the present invention, various known additives such as antioxidants, ultraviolet absorbers, heat stabilizers, and the like may be added, if necessary, within a range not impairing the object of the present invention.
Lubricants, flame retardants, may contain additives such as antistatic agents, also other thermoplastic resins, for example polyvinyl chloride resin, polyamide resin, polyimide resin, polyester resin, polycarbonate resin, A polyacetal resin, a polyaromatic ether ketone resin, a polyphenylene ether resin, a polyphenylene sulfide resin, a styrene resin, a polyaromatic ester resin, a polysulfone resin, an acrylate resin, or the like may be added.

The electroless-platable polyolefin resin molded product of the present invention is prepared by blending the respective components in predetermined proportions, and using a Banbury mixer, a single-screw extruder, a twin-screw extruder, a co-kneader, a multi-screw extruder. After the resin composition is sufficiently kneaded at a suitable temperature by a method such as the above, the resin composition is molded into a desired shape by, for example, an injection molding method or an extrusion molding method, and then (a) a skin layer is removed from the surface. , (B) a process of etching an inorganic substance on the surface with an acid to form an anchor hole, (c) a process of imparting polarity, and (d) a process of adsorbing catalyst particles.

In the treatment for removing the skin layer in the step (a), for example, dichromic acid, a mixed solution of dichromic acid and sulfuric acid,
Chromic acid, trichloroethane, trichloroethylene, xylene, etc. are used. Among these, dichromic acid and a mixed solution of dichromic acid and sulfuric acid are particularly preferably used. In this case, the concentration is 20 to 90% by weight and the treatment time is 1 to 20%.
About a minute is preferable.

In the process of forming the anchor holes in the step (b), hydrochloric acid, sulfuric acid, acetic acid, nitric acid or the like is used as an etching agent, and hydrochloric acid is particularly preferable. In this case, the concentration is preferably about 5 to 40% by weight, and the etching treatment is preferably performed at a temperature in the range of 30 to 40 ° C. for about 1 to 5 minutes.

The treatment for imparting polarity in the step (c) is for attaching a catalyst having polarity, and is applied for imparting a positive charge to the surface of the polyolefin (including in the anchor). A water-soluble polymeric amine or the like is usually used for this treatment. In this case, the concentration is preferably in the range of 1 to 20% by weight, and the temperature is preferably in the range of 20 to 60 ° C. for about 1 to 10 minutes.

In the treatment (d) of adsorbing the catalyst particles, which is finally performed, colloidal particles of stannous chloride / palladium chloride having a negative charge are usually used as the catalyst particles. In this case, for example, stannous chloride 50 to 3
A solution containing about 1 to 5 mol of an alkali metal salt in a solution containing 00 mg / liter and 1 to 10 g / liter of palladium chloride is used and treated at a temperature in the range of 20 to 50 ° C. for about 1 to 10 minutes. Good.

The electroless-platable polyolefin resin molded product of the present invention thus obtained can be easily coated with high adhesion by electroless plating on its surface.

[0023]

EFFECTS OF THE INVENTION According to the present invention, a polyolefin resin molded product having an electroless plating coating capable of performing electroless plating while maintaining the excellent properties of polyolefin and exhibiting an electromagnetic wave shielding effect at low cost. Can be easily obtained.

[0024]

The present invention will be described in more detail by way of examples, which should not be construed as limiting the invention thereto.

Each physical property was evaluated as follows. (1) Plating film strength The plating film strength at the initial stage and after the heat cycle test was determined as follows. Plating surface is a grid (1 mm grid is 1
It was cut into 100 pieces and a peeling test was performed with cellophane tape, and the number of the peeled cells was evaluated with respect to 100 cells. ◯: 0/100 (the number of squares where peeling occurred is 0) Δ: 1 to 10/100 ×: 11 to 50/100 XX: 51/100 or more

(2) Shielding effect The shielding effect was measured by the Advantest method at the initial stage and after the heat cycle test. The heat cycle test in (1) and (2) above is 100 ° C. × 0.5 hours-4
It was performed by performing a heat cycle of 0 ° C. × 0.5 hours 500 times.

Production Example 1 After dry-blending the components in the types and amounts shown in Table 1, the ingredients were quantitatively supplied to a hopper of a twin-screw kneader TEM-35 [manufactured by Toshiba Machine Co., Ltd.] and kneaded at 200 ° C. It was In addition,
The fibrous filler (fibrous magnesium oxysulfate, glass fiber) was quantitatively supplied and kneaded to an intermediate portion (downstream from the resin melting portion) of the biaxial kneader.

The obtained pellets were injection-molded to form a flat plate for plating and subjected to a test.

[0029]

[Table 1]

Example 1 Using a 120 × 120 × 3 mm flat plate made of the composition a, in step (a), the resin surface layer was etched with a dichromic acid solution, and then treated with sulfate hydrazine as a reducing agent. . Then, in step (b), the inorganic substance was etched with hydrochloric acid to form anchor holes. After washing, in the step (c), a water-soluble high-molecular amine (trade name, manufactured by EMC-1552 Spray Co., Ltd.) was used to impart a positive polarity to the surface. Next, in the step (d), negatively charged catalyst particles composed of stannous chloride / palladium chloride colloidal particles were adsorbed on the surface.

The plate thus treated was subjected to electroless copper plating (film thickness 1.5 μm), and then electroless nickel plating (film thickness 0.25 μm). The performance of this plate was evaluated.

Example 2, Comparative Examples 1 and 2 The same as Example 1 except that the plate made of the composition a was replaced by the plate made of the compositions b, c and d. A plated plate was prepared by using the method and its performance was evaluated.

Comparative Example 3 A plated plate was prepared in the same manner as in Example 1 except that the polarity imparting process in step (c) was not performed, and its performance was evaluated.

Comparative Example 4 A plating plate was prepared in the same manner as in Example 1 except that the polarity imparting process in the step (c) and the catalyst adsorption process in the step (d) were not performed in the example 1. Then, the performance was evaluated.

Comparative Example 5 A plated plate was prepared in the same manner as in Example 1 except that the anchor hole forming process in the step (b) was not performed, and its performance was evaluated.

The treatment steps in Examples 1 and 2 and Comparative Examples 1 to 5 are shown in Table 2 and the performance evaluation results of the plated plate are shown in Table 3.

[0037]

[Table 2]

[0038]

[Table 3]

Production Example 2 The compositions shown in Table 4 were prepared in the same manner as in Production Example 1, and a flat plate for plating was formed and subjected to the test.

[0040]

[Table 4]

(Note) EPR: EPO2P manufactured by Nippon Synthetic Rubber Co., Ltd.

Comparative Examples 6 and 7, Examples 3, 4, and 5 In Example 1, instead of the plate made of the composition a, the plates made of the compositions e, f, g, h, and i shown in Table 4 were used. A plating plate was prepared in the same manner as in Example 1 except that was used, and its performance was evaluated. Table 5 shows the treatment steps, and Table 6 shows the evaluation results of the performance.

[0043]

[Table 5]

[0044]

[Table 6]

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yoshiaki Miura 1 Anesaki Kaigan, Ichihara City, Chiba Prefecture Idemitsu Petrochemical Co., Ltd. (72) Inventor Kenichi Tsukada 6-4-22 Tsunashima Nishi, Kohoku Ward, Yokohama City, Kanagawa Prefecture

Claims (2)

[Claims] 1. A surface of a molded article made of a resin composition containing 50 to 90% by weight of a polyolefin resin (A) and 50 to 10% by weight of an inorganic substance (B) which is soluble in an acid, and (A) a skin. Treatment for removing the layer, (b) Treatment for etching an inorganic substance on the surface with an acid to form an anchor hole, (c)
An electroless-platable polyolefin resin molded product, which is sequentially subjected to a treatment for imparting polarity and (d) a treatment for adsorbing catalyst particles. 2. Insoluble in (C) acid, relative to 100 parts by weight of a mixture containing (A) 50 to 90% by weight of polyolefin resin and (B) 50 to 10% by weight of acid-soluble inorganic substance. (B) a treatment for removing the skin layer on the surface of a molded product made of a resin composition containing at least one selected from an inorganic substance and an elastomer in a proportion of 70 parts by weight or less, and (b) a surface inorganic substance. Polyolefin resin molding capable of electroless plating, characterized in that an acid is etched with an acid to form an anchor hole, (c) a process of imparting polarity, and (d) a process of adsorbing catalyst particles are sequentially performed. body.