JPH0713318B2 - Method for producing surface metallized thermoplastic polyester resin molded article - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a method for surface metallizing a thermoplastic polyester resin molded article by plating. More specifically, the present invention relates to a method for producing a surface metallized thermoplastic polyester molded article which has an excellent adhesive strength to a plated film, has a good surface appearance, and has excellent plated thermal cycleability and impact resistance of the molded product.

<Prior Art> Generally, the plastic plating process includes (1) pretreatment,
(2) Roughening treatment (etching), (3) Sensitization treatment (sensitizing) or carrier treatment,
The steps (4) activation treatment (activating) or acceleration treatment, (5) electroless plating and (6) electric plating are sequentially performed, and the above steps (3) and above are usually performed. It is called a process. Among them, the roughening treatment (2) is an important step that influences the adhesion of the metal plating film applied in the subsequent plating step, and various means are used depending on the type of plastic.

As a means for roughening the surface of the thermoplastic polyester resin for plating, for example, a method in which a polyester resin containing a filler in advance is subjected to roughening treatment with an alkaline solution and then plated (JP-A-54-15977), glass fiber / carbonic acid A method of roughening a calcium-reinforced polyester resin with an alkali hydroxide solution containing an oxidizing agent and then plating (JP-A-53-6374), immersing the glass fiber-reinforced polyester resin in an aqueous nitric acid solution, Then, a method of immersing in an aqueous solution of alkali hydroxide to roughen the surface and then plating (JP-A-53-6376), a method of treating the resin film with an alkaline solution, and then treating with a chromic acid mixed solution and then plating (JP-A-58-58) No. 149924) is known, but these methods are substantially effective although the adhesion of the plating film is somewhat improved. It is not possible to obtain a practically excellent surface metallized thermoplastic polyester resin molded product because it does not reach the level, and the glitter appearance of the matte appearance is not obtained, and the matte thermal cycle property and the impact resistance of the matte product are insufficient. .

<Problems to be Solved by the Invention> An object of the present invention is to solve the above-mentioned drawbacks of the prior art, to provide a practical adhesive film with excellent adhesive force and excellent surface appearance. Another object of the present invention is to provide a surface-metallized thermoplastic polyester resin molded article having excellent impact resistance of the matte product.

<Means and Actions for Solving Problems> That is, the present invention contains 5 to 250 parts by weight of a filler, 100 parts by weight of a thermoplastic polyester, and an aliphatic dicarboxylic acid copolymerized polyester, a polyester elastomer and a glycidyl group. A molded product of a thermoplastic polyester resin composition containing 0.5 to 80 parts by weight of one or more thermoplastic resins selected from olefin-based copolymers is treated with an alkaline solution to roughen the surface, and then a plating treatment is performed. In the step of applying, it is a method for producing a surface metallized thermoplastic polyester resin molded article in which all or part of the electric nickel paste layer is a matte nickel paste layer and / or a semi-gloss nickel paste layer, and as a particularly preferred embodiment, this production In the method, titanium dioxide, aluminum oxide, meta Calcium Lee acid,
Provided is a method for producing a surface metallized thermoplastic polyester resin molded article using one or more kinds selected from mica, talc, calcium carbonate and glass fiber.

The thermoplastic polyester used in the present invention is usually 90
A polymer obtained by polycondensing a dicarboxylic acid component having a terephthalic acid component of at least mol% and a diol component is used.

The terephthalic acid component as used herein is terephthalic acid and its ester-forming derivative, and other dicarboxylic acid components used together with the terephthalic acid component are isophthalic acid, orthophthalic acid, 2,6-naphthalenedicarboxylic acid, 1 -5-naphthalenedicarboxylic acid, bis (P-carboxyphenyl) methaneanthracene dicarboxylic acid, 4.4'-diphenyldicarboxylic acid, 1.2
-Bis (phenoxy) ethane-4,4'-dicarboxylic acid, aromatic dicarboxylic acid such as 5-sodium sulfoisophthalic acid, adipic acid, sebacic acid, azelaic acid,
Aliphatic dicarboxylic acids such as dodecanedioic acid, 1.3-
Examples thereof include alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid, and ester-forming derivatives thereof. As the diol component, an aliphatic glycol having 2 to 20 carbon atoms, that is, ethylene glycol, propylene glycol, 1 ·
4-butanediol, neopentyl glycol, 1.5
-Pentanediol, 1.6-hexanediol, decamethylene glycol, cyclohexanedimethanol, cyclohexanediol and the like, and ester-forming derivatives thereof.

Preferred specific examples of these polymers or copolymers include polybutylene terephthalate, polybutylene (terephthalate / isophthalate), polybutylene (terephthalate / adipate), polybutylene (terephthalate / sebacate), polybutylene (terephthalate / terephthalate /
Decanedicarboxylate), polyethylene terephthalate, polyethylene (terephthalate / isophthalate), polyethylene (terephthalate / adipate),
Examples thereof include polybutylene (terephthalate / 5-sodium sulfoisophthalate) and polyethylene (terephthalate / 5-sodium isophthalate). Polybutylene terephthalate, polybutylene (terephthalate / adipate), polybutylene (terephthalate / terephthalate / Decanedicarboxylate), polyethylene terephthalate, polyethylene (terephthalate / adipate), polybutylene (terephthalate / 5-sodium sulfoisophthalate) and the like are particularly preferably used. Further, it is preferable that the thermoplastic polyester has a relative viscosity of 1.2 to 2.0, particularly 1.3 to 1.85 when measured at 25 ° C. in a 0.5% o-chlorophenol solution.

Moreover, these can be used in mixture of 2 or more types.

The filler used in the present invention is a filler having a form such as granular, needle-like, flaky, plate-like and fibrous forms, titanium dioxide, aluminum oxide, calcium metasilicate, mica, talc, calcium carbonate, Barium sulfate, gypsum, zirconium oxide, antimony trioxide, clay, silica, sericite, magnesium oxide, kaolin, diatomaceous earth, magnesium carbonate, feldspar, vermiculite, carbon black, glass beads, shirasu balloon and siloid,
Examples thereof include glass fiber, carbon fiber, ceramic fiber, gypsum fiber, and potassium whisker titanate. Of these, titanium dioxide, aluminum oxide, calcium metasilicate, mica, talc and calcium carbonate are preferably used, and titanium dioxide, aluminum oxide, mica and glass fiber are particularly preferably used.

You may use these fillers in mixture of 2 or more types.

The amount of the filler added is required to be 5 to 250 parts by weight, preferably 30 to 100 parts by weight, based on 100 parts by weight of the thermoplastic polyester. If it is less than 5 parts by weight, the effect of improving the adhesiveness of the plating film is insufficient. If it exceeds 250 parts by weight, the surface roughness of the molded article becomes too large, and on the contrary, the adhesive strength of the plating film and the glitter of the plating are lost, and the mechanical properties of the thermoplastic polyester resin itself are deteriorated, which is not preferable.

The blending means of the thermoplastic polyester and the filler of the present invention, the specific thermoplastic resin and other additives described below is not particularly limited, and examples thereof include a thermoplastic polyester, a filler, a specific thermoplastic resin and other additives. A method in which the raw materials blended together are supplied to a screw type extruder and melt-extruded and mixed can be adopted.

As the thermoplastic polyester resin composition molded article of the present invention, any resin molded article such as an injection molded article, an extrusion molded article and a blow molded article can be adopted.

A method of heat-treating the thermoplastic polyester resin molded article of the present invention before using it for plating treatment is also a preferable method for improving the physical properties of the surface metallized molded article.

The heat treatment temperature is preferably in the range of 70 to 170 ° C.

The alkaline solution of the present invention is an alkaline component such as potassium hydroxide, sodium hydroxide or magnesium hydroxide,
It is a solution dissolved in a solvent such as water, phenols, alcohols or the like or a mixed solvent thereof at a concentration of 5 to 50% by weight, and particularly an aqueous solution of 10 to 40% by weight of sodium hydroxide and / or potassium hydroxide. It is preferably used.

Further, a surfactant or the like can be added if necessary.

The treatment conditions with the alkaline solution of the present invention are preferably such that the molded article is immersed in the alkaline solution at 5 to 95 ° C. for 1 to 120 minutes, particularly 40 to 90 ° C. and 2 to 60 minutes. It is desirable to carry out the immersion treatment.

Next, it is desirable to wash thoroughly.

After the treatment with the alkaline solution is completed, the molded article may be sufficiently washed with water, and then further surface-treated with an acidic aqueous solution of PH3 or less. Mineral acids such as sulfuric acid and hydrochloric acid are used as the acid component in this case, and the treatment conditions are preferably 5 to 70 ° C. and 2 to 60 minutes.

Further, it is more preferable to treat with an acidic chromic acid solution before treating with the alkaline solution of the present invention. That is, the acidic chromic acid solution selectively permeates the interface between the filler and the thermoplastic polyester to swell the polyester in that portion, and when the polyester is subsequently hydrolyzed in an alkaline solution, this swollen portion is It is presumed that it is hydrolyzed faster than the others, the filler is likely to be released, and unevenness with a deep bottom and excellent anchor effect is formed on the surface of the molded product.

The acidic chromic acid solution is an acidic oxidizing solution containing a chromium compound having a valence of 6 as a main component, sulfuric acid, and water, and other mineral acids as necessary.

The composition of the solution is 0.02 to 50% by weight of a hexavalent chromium compound, 10 to 99.95% by weight of sulfuric acid, 0 to 97% by weight of water, and 0 to 50% by weight of other mineral acids, and particularly chromium of a hexavalent value. Compound 0.2
-20% by weight, sulfuric acid 20-98.8% by weight, water 0-80% by weight are preferably used.

Examples of the hexavalent chromium compound include chromium trioxide, chromate salts (eg potassium chromate, sodium chromate, etc.), dichromate salts (eg potassium dichromate, sodium dichromate, etc.), etc. You can Chromium trioxide, potassium dichromate and sodium dichromate can be preferably used.

Moreover, phosphoric acid, sulfuric acid, etc. can be mentioned as other mineral acids.

The treatment conditions with the acidic chromic acid solution of the present invention are 5 to 95
It is preferable to immerse the molded article in the acidic chromic acid solution at a temperature of 0.25 to 60 minutes, particularly 40 to 90 ° C and 1 to 40.
The immersion treatment is optimal within the range of minutes.

Then, it is desirable to wash with water.

In this way, the resin molded product having the roughened surface is subjected to the usual electroless plating treatment.

The electroless plating process includes, for example, sensitizing with a stannous chloride solution, activating with a palladium chloride solution, electroless copper or nickel plating steps, or catalyzing-accelerating-electroless plating steps. A usual electroless plating method can be applied.

The resin molded article thus treated by electroless plating is then subjected to electric activation after surface activation, and at this time, all or part of the electric nickel plating layer is made into a semi-gloss nickel plating. At this time, the thickness of the glossy nickel plating layer and the thickness of the matte and / or semi-glossy nickel layer are preferably in the range of 0/10 to 8/2, more preferably 0/10 to 6/4. Incidentally, an electric copper plating may be performed before the electric nickel plating.

When all of the electric nickel layer is glossy nickel, the metal thermal cycling property and the impact resistance of the metal article are insufficient, and the object of the present invention cannot be achieved.

In the present invention, a specific thermoplastic resin, that is,
One or more selected from aliphatic dicarboxylic acid copolymerized polyesters, polyester elastomers and glycidyl group-containing olefin copolymers, by adding to the thermoplastic polyester and the filler of the present invention mechanical properties of the medicated article of the present invention and It is possible to further improve the thermal properties.

These aliphatic dicarboxylic acid copolymerized polyester, selected from polyester elastomers and glycidyl group-containing olefin copolymers, the addition amount of one or more thermoplastic resins, 0.5 to 80 parts by weight with respect to 100 parts by weight of the thermoplastic polyester. Parts, preferably 5 to 50 parts by weight.

The term "aliphatic dicarboxylic acid copolyester" as used herein is a copolymer composed of 10 to 50 mol%, preferably 15 to 40 mol% of a dicarboxylic acid which is an aliphatic dicarboxylic acid component and a diol component.

Specific examples of these copolymers include polybutylene (terephthalate / adipate), polybutylene (terephthalate / sebacate), polybutylene (terephthalate /
Decanedicarboxylate), polybutylene (terephthalate / isophthalate / sebacate), polybutylene (terephthalate / isophthalate / decanedicarboxylate), polyethylene (terephthalate / adipate), polyethylene (terephthalate / sebacate) and the like can be mentioned.

In addition, aliphatic dicarboxylic acid copolyester is 0.5%
Those having a relative viscosity of 1.2 to 2.0, especially 1.3 to 1.85, when the o-chlorophenol solution of is measured at 25 ° C. are preferable.

Moreover, these can be used in mixture of 2 or more types.

The polyester elastomer used in the present invention means a polyether ester block copolymer, a polyester / ester block copolymer, a polyester having a hard segment of polyester and a soft segment of poly (alkylene oxide) glycol and / or an aliphatic polyester. It is an ether ester / ester block copolymer.

Here, the aromatic polyester constituting the hard segment is a polymer obtained by polycondensing a dicarboxylic acid component having a terephthalic acid component of 60 mol% or more and a diol component. The dicarboxylic acid component and the diol component other than terephthalic acid are the same as in the case of the thermoplastic polyester, and are omitted here.

Specific examples of the aromatic polyester preferably include polyethylene terephthalate, polybutylene terephthalate, polyethylene (terephthalate / isophthalate), polybutylene (terephthalate / isophthalate) and the like.

Specific examples of the poly (alkylene oxide) glycol constituting the soft segment and the aliphatic polyester here include polyethylene glycol and poly (1
-2- and 1.3-propylene oxide) glycol, poly (tetramethylene oxide) glycol, copolymer of ethylene oxide and propylene oxide, copolymer of ethylene oxide and tetrahydrofuran, polyethylene adipate, polybutylene adipate, poly-ε-
Preferred are caprolactone, polyethylene sebacate, polybutylene sebacate and the like.

The weight ratio of soft segment to polyester hard segment of polyester elastomer is 95/5.
It is preferably from 10 to 90, particularly from 90/10 to 30/70.

Specific examples of the polyester elastomer include polyethylene terephthalate / poly (tetramethylene oxide)
Glycol block copolymer, polyethylene terephthalate / isophthalate / poly (tetramethylene oxide) glycol block copolymer, polybutylene terephthalate / poly (tetramethylene oxide) glycol block copolymer, polybutylene terephthalate / isophthalate poly (tetra Methylene oxide) glycol block copolymer, polybutylene terephthalate / decanedicarboxylate poly (tetramethylene oxide) glycol block copolymer, polybutylene terephthalate / poly (propylene oxide / ethylene oxide) glycol block copolymer, polybutylene terephthalate / Isophthalate / poly (propylene oxide / ethylene oxide) glycol block copolymer, polybutylene terephthalate Over DOO / decanedicarboxylate rate poly (propylene oxide / ethylene oxide) glycol bromide poke copolymer, polybutylene terephthalate poly (ethylene oxide) glycol bromide poke copolymer, polybutylene terephthalate-polyethylene adipate Bro poke copolymer, polybutylene terephthalate
Preferable examples include polybutylene adipate block copolymers, polybutylene terephthalate / polybutylene sebacate block copolymers, polybutylene terephthalate / poly-ε-caprolactone block copolymers, and the like.

Among these polyester elastomers, especially polybutylene terephthalate / poly (tetramethylene oxide) glycol block copolymer, polybutylene terephthalate / isophthalate / poly (tetramethylene oxide) glycol block copolymer, polybutylene terephthalate poly ( Propylene oxide / ethylene oxide) glycol block copolymer, polybutylene terephthalate / isophthalate poly (propylene oxide / ethylene oxide) glycol block copolymer,
Polybutylene terephthalate / polybutylene adipate block copolymers and polybutylene terephthalate / poly-ε-caprolactone block copolymers are preferably used because they have a great effect of improving the physical properties of the polyester resin composition.

Further, the relative viscosity measured in the same manner as the thermoplastic polyester of these polyester elastomers is 1.4 to 4.0,
Those in the range of 1.6 to 3.0 are particularly preferable.

Two or more of these polyester elastomers can be mixed and used.

The glycidyl group-containing olefin copolymer used in the present invention is composed of 50 to 99.5% by weight of α-olefin, 50 to 0.5% by weight of glycidyl ester of α / β-unsaturated carboxylic acid, and 0 to 49.5% by weight of vinyl acetate. Is a copolymer of
As used herein, α-olefin is ethylene, propylene,
Butene-1 and the like, and ethylene is preferably used. Further, the glycidyl ester of α / β-unsaturated carboxylic acid has the general formula (R in the formula represents a hydrogen atom or a lower alkyl group), and specific examples thereof include glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, and among others, glycidyl methacrylate is preferably used. .

Α in olefin copolymers containing glycidyl groups
The copolymerization amount of glycidyl ester of β-unsaturated carboxylic acid is 0.5 to 50% by weight, particularly 1 to 20% by weight, and 0.5
If the amount is less than 50% by weight, the effect of the present invention cannot be obtained, and if it exceeds 50% by weight, the composition tends to gel during melt-kneading, which is not preferable.

Specific examples of the olefin copolymer having a glycidyl group include ethylene / glycidyl methacrylate copolymer and ethylene / glycidyl methacrylate / vinyl acetate copolymer. These can be used as a mixture of two or more kinds.

When using a glycidyl group-containing olefin copolymer, an organic sulfonic acid metal salt such as sodium dodecylbenzene sulfonate or sodium dodecyl sulfonate and a sulfuric acid ester salt of alcohol such as lauryl sulfate / sodium salt are used. Etc. can be added together in a small amount.

Also, other additives such as aluminum stearate,
Lubricants such as barium stearate, release agents such as montan wax and wax metal montanate, plasticizers, heat stabilizers, UV absorbers, pigments, dyes, and other thermoplastic resins can be added.

Since the surface metallized thermoplastic polyester resin molded article of the present invention has excellent heat resistance, adhesiveness to the plating film, and surface glitter, it is useful as various automobile parts, electric parts and mechanical parts.

<Examples> The effects of the present invention will be further described with reference to the following examples.

The abbreviations used in the examples mean the following.

PBT: Polybutylene terephthalate PBT / D: Polybutylene (terephthalate / decanedicarboxylate) (terephthalic acid component / decanedicarboxylic acid component copolymerization molar ratio = 80/20) E / GMA: ethylene / glycidyl methacrylate copolymer (copolymerization Weight ratio 90/10) PBT-PTMG: Polybutylene terephthalate-Poly (tetramethylene oxide) glycol block copolymer (soft segment / hard segment weight ratio 40/60) -Examples / Comparative Examples 0.5% orthochlorophenol solution Thermoplastic polyester 100 containing polybutylene terephthalate having a relative viscosity of 1.57 when measured at 25 ° C., an aliphatic dicarboxylic acid copolymer polyester, a polyester elastomer, and an olefin copolymer having a glycidyl group in the proportions shown in Table 3.
The fillers shown in Table 3 were further blended with respect to parts by weight, and melt-kneaded with an extruder having a 65 mmφ screw set at 250 ° C. to form pellets. Then, the pellets obtained were subjected to a 5 ounce injection molding machine set at 250 ° C, and a 100φ x 3mm disk molded product and a 1/8 "wide notched impact test piece were obtained under the condition of a mold temperature of 80 ° C. Molding was carried out to obtain test pieces, which were heat-treated at 140 ° C. for 2 hours, and then the test pieces were treated by the method shown in Table 1 including treatment with acidic chromic acid solution and alkaline solution. The composition of the electric nickel plating bath is shown in Table 2.

In the thermal cycle test of the metal plating, (11) the test piece subjected to the electric metal plating (chrome plating) is treated under the following conditions, and 130 ° C (1hr) → -30 ° C (1hr) is carried out for 5 cycles.

After carrying out, 140 ℃ (1hr) → -30 ℃ (1hr)
5 cycles.

After carrying out, carry out 5 cycles at 150 ℃ (1hr) → -40 ℃.

After the completion, after the completion and after the completion of the appearance, the appearance was visually observed for the presence or absence of abnormalities (blister, peeling, cracking, etc.) on the surface of the matte, and evaluated. As for impact test pieces, AS
An Izod impact test was conducted according to TMD256.

The results are shown in Table 3.

As is clear from the results shown in Table 3, the surface metallized polyester molded product of the present invention is superior to the matte product manufactured by the conventional method in the matte thermal cycle property and the impact resistance of the matte product.

<Effects of the Invention> The surface-metallized thermoplastic polyester resin molded article obtained by the method of the present invention has excellent adhesive properties for plated films, plated surface bright thermal cycling properties and impact resistance.

Claims (2)

[Claims] 1. A filler of 5 to 250 parts by weight per 100 parts by weight of a thermoplastic polyester, and one or more heats selected from aliphatic dicarboxylic acid copolymer polyesters, polyester elastomers and glycidyl group-containing olefin copolymers. After subjecting a molded product of a thermoplastic polyester resin composition containing 0.5 to 80 parts by weight of a plastic resin to roughening by treating with an alkaline solution, in a step of performing a plating treatment, all or part of an electric nickel plating layer Is a matte nickel plating layer and / or a semi-gloss nickel plating layer, and a method for producing a surface metallized thermoplastic polyester resin molded article. 2. The surface metallized thermoplastic polyester according to claim 1, wherein the filler is one or more selected from titanium dioxide, aluminum oxide, calcium metasilicate, mica, talc, calcium carbonate and glass fiber. Manufacturing method of resin molded product.