JPS59142228A - Surface treatment of resin molding - Google Patents

Abstract

PURPOSE:To impart paintability, printability, platability, and adhesiveness to a molding formed from a resin excellent in heat resistance and moldability, by treating the surface of the molding formed from a specified aromatic polyester, with a low-temperature plasma. CONSTITUTION:Low-temperature plasma treatment is applied to the surface of a molding obtained from an aromatic polyester comprising the structural units of formulas I (wherein the carbonyl groups are m- or p- to each other), II(wherein each O is m- or p- to the SO2 group), and III (wherein X is a bivalent 1-10C hydrocarbon group, O, CO, SO, or SO2, a is 0 or 1, R1-R4 are each H, a 1-8C hydrocarbon group, or a halogen atom, and all of R1-R4 are not hydrogen at the same time), wherein the ratio of the number of structural units I to that of structural units II is 1:0.36-1.06, the ratio of the number of structural units I to that of structural units III is 1:0.04-0.66, the ratio of the number of structural units I to the total of those of structural units II and III is 1:0.90- 1.10, and the logarithmic viscosity of the polymer is 0.2-2.0.

Description

Detailed Description of the Invention The present invention provides a method for imparting paintability, printability, plating performance, and adhesiveness to molded products obtained from aromatic polyester resins that have excellent heat resistance and moldability. It relates to a surface treatment method.

Terephthalic acid, isophthalic acid or derivatives thereof;
Aromatic polyesters produced by polycondensation with 2,2-bis(4'-hydroxyphenyl)propane or its derivatives have mechanical properties such as tensile strength and flexural strength,
It is known that this resin has excellent performance in terms of thermal properties such as heat distortion temperature and thermal decomposition temperature, and other electrical properties. However, although the thermal properties have been improved compared to aromatic aliphatic polyesters such as polyethylene terephthalate, in recent years, considering the heat resistance required for high-performance resins, the thermal properties of the above aromatic polyesters have improved. The properties are still not necessarily satisfactory. - In particular, these high-performance resins are often used in the electrical and electronic fields, and are now required to have heat resistance in solder baths, for example. In order to satisfy such demands in the practical field, the conventionally known aromatic polynisdels as described above are clearly insufficient in terms of performance, and it is necessary to further improve the usable temperature range of the resin. It is.

The present inventors first discovered the following formulas A and B as aromatic polyesters with further improved thermal performance without sacrificing the excellent mechanical properties and electrical properties of aromatic polyesters.
and C, the ratio of the number of structural units A to the number of structural units B is 0136 to 1.06, and the ratio of the number of structural units A to the number of structural units C is 1. : 0
．． 04 to 0.66, the number to the structural unit and the structural unit B
An aromatic polyester having a ratio to the sum of plus C of 1:0.90 to 110 and a polymer logarithmic viscosity of 0.2 to 20 [However, in the above formula, in A, the carbonyl groups are mutually meta or At the para position, the oxygen atom is 80. In formula C, the oxygen atom is in meta or para position to X. X in 20 represents a divalent hydrocarbon group having 1 to 10 carbon atoms, 0', Co, S, So, or 80°, and a is 0 or l. R and ~R4 each represent hydrogen, a hydrocarbon group having 1 to 8 carbon atoms, or a halogen atom, and may be the same or different, but when X is SO8, 1 and ~R4 are all hydrogen at the same time. I found that there is no. This aromatic polyester has excellent heat resistance, mechanical properties, and moldability, and is expected to be used in the fields of mechanical parts, aircraft parts, automobile parts, electronics, and electrical parts (
・Ru. Particularly in the field of electronic and electrical components, its excellent electrical properties are being exploited, and its application to various types of insulation, printed circuit boards, etc. is being considered. When applied to these applications, although the aromatic polyester is a polar polymer, if the surface of the molded product is left untreated, the paintability, adhesion, and plating properties are insufficient.
Is it necessary to perform some kind of surface treatment?

Conventionally, methods for surface treatment of thermoplastic resin molded articles include corona treatment, flame treatment, acid treatment with a mixture of chromic acid and concentrated sulfuric acid, and organic solvent treatment with trichlorethylene and the like. Among these treatment methods, corona treatment,
Flame treatment is not suitable for molded products with complex shapes.

Although the aromatic polyester used in the present invention has many excellent properties, it has poor resistance to chemicals used in chemical treatments, such as being soluble in concentrated sulfuric acid and whitening in trichlorobenzene, trichloroethylene, etc. Acid treatment and organic solvent treatment cannot be applied. For this reason, the present inventors investigated various methods for surface treatment of molded articles obtained from the above-mentioned aromatic polyester resin, and as a result, found that a low-temperature plasma treatment method was effective, and completed the present invention. That is, the present invention provides a method for surface treatment of a resin molded article, which is characterized in that the surface of a molded article obtained from an aromatic polyester resin having excellent heat resistance and moldability is treated with low-temperature plasma. It is something to do.

The aromatic polyester used in the present invention consists of structural units represented by the following formulas A, B, and C, and the ratio of the number of structural units to the number of structural units B is 1:036 to 106.
and the ratio of the number of structural units A to the number of structural units C is 1:0
．． 04 to 066, the ratio of the number of structural units A to the sum of structural units B plus C is 1:0.90 to 1.10, and the logarithmic viscosity of the polymer is 02 to 20. It is.

[However, in the above formula, in 2A, the carbonyl groups are in the meta or para position to each other, and in 2B, the oxygen atom is SO
in the meta or para position to one group, in the formula CVc,
The oxygen atom is in the meta or para position to X. Formula C
X in is a divalent hydrocarbon group having 1 to 1° of carbon atoms, 0
, Co, S, So or So.

and a is O or 1. 1 and 1 to 17 each represent hydrogen, a hydrocarbon group having 1 to 8 carbon atoms, or a rogen atom, and may be the same or different, but when X is SO7
When R, ~J, are not all hydrogen at the same time] Isophthalic acid, terephthalic acid, or derivatives thereof are mentioned as the dicarboxylic acid component corresponding to the structural unit 2A used in the polyester of the present invention. . These may be used alone or as a mixture of two or more.

When a mixture of isophthalic acid and terephthalic acid components is used, the molar ratio of the former to the latter is preferably in the range of 5:95 to 95.5, particularly preferably 30.70 to 70:30.
is within the range of

Examples of the dicarboxylic acid derivatives include dichloride and diester. When a diester is used, raw materials constituting the ester include lower aliphatic alcohols having 1 to 10 carbon atoms and phenols having 6 to 18 carbon atoms. Specific examples of diesters include dimethyl terephthalate, dimethyl isophthalate, diethyl isophthalate, diethyl terephthalate, diisoprobilisophthalate, diropropyl terephthalate, diisobutyl isophthalate, diphenyl isophthalate,
Examples include diphenyl terephthalate, dibenzyl isophthalate, and dibenzyl terephthalate. Also,
Mixed diesters and monoesters (C half esters) esterified with two types of alcohols can also be used.

As the bisphenol component corresponding to the structural unit 2B of the present invention, bis(hydroxyphenyl)sulfones are used. Bis(hydroxyphenyl)sulfones include bis(4-hydroxyphenyl)sulfone, bis(
3-hydroxyphenyl) sulfone, 3-hydroxyphenyl 4-hydroxyphenyl sulfone. Bis(hydroquinphenyl)sulfones can be used either individually or as a mixture of isomers.

Particularly preferred is (technique, bis(4-hydroxyphenyl))
It is a sulfone.

When the above-mentioned bis(hydroxyphenyl) sulfones are subjected to the reaction with a hydroxyl group or as various derivatives such as salts with alkali metals or alkaline earth metals or esters with aliphatic or aromatic carboxylic acids. There is also. The most suitable one is selected depending on the method and form of the polymerization reaction.

In the present invention, as the bisphenol component corresponding to the structural unit of formula C, bisphenols represented by the following general formula I1 (in the formula, X, a, R,, R,, R,, R4 are as described above) are used. be done.

Specific examples of bisphenols of formula I include 2,2-bis(47-hydroxyphenyl)propane, bis[4-hydroxyphenyl]methane, 2,2-bis(4'-hydroquine 3'- methylphenyl), propane, 2,2-bis(3'-chloro4'-hydroquinphenyl)propa/, 1,1-bis(4'-hydroxyphenyl)chlorohexane 1,1-his(4'-hydroquine) phenyl) isophutane, 1,1-bis(4'-hydroquinophenyl)diphenylmethane, 2,2-bis(3'
, 5/-dimethyl4'-hydroquinphenyl)propane, bis(3,5-dimethyl4-hydroxyphenyl)
Methane, bis(4-hydroginphenyl)ether,
Bis(4-hydroquinphenyl) sulfide, bis(4
-hydroxyphenyl) sulfoginode, bis(3,5-
methyl 4-hydroxyphenyl) sulfide, bis(
3,5-dimethyl 4-hydroquinphenyl) sulfone,
4,4'-dihydroquinbiphenyl, 3,3',
5.5'-tetramethyl 4°4'-dihydroquinbiphenyl, 2,2-bis(3'.

5'-dibromo4'-hydroxyphenyl)propane,
Bis(4-hydroxyphenyl)ketone, 2,2-bis(3',5'-diphenyl 4'-hydroquinphenyl)
Propane, l, 1-bis(4'-hydroquinphenyl)
1-phenylethane, bis(3,-hydroquinphenyl) sulfide, bis(3-hydroxyphenyl)sulfo7.3'+ 3'-dihydroxybiphenyl, bis(
Examples include 3-hydroxyphenyl) ether, 3-hydroxyphenyl 4-hydroxyphenyl ether, and the like.

They can be used alone or as a mixture of two or more.

Preferably, 2,2-bis(4'-hydroquinphenyl)propane, bis(4-hydroquinphenyl)methane,
2,2-bis(3'-5'-dimethyl4'-hydroxyphenyl)bronokun, bis(4-hydroxyphenyl)ether, bis(4-hydroquinphenyl)sulfide, bis(3,5-dimethyl4) -hydroxyphenyl)
Sulfone, 4I4'-dihydroxybiphenyl, 313
Examples include '+515'-tetramethyl 4,4'-dihydroxybiphenyl and bis(4-hydroxyphenyl)ketone.

To prepare the polymers of the present invention, bis[hydroquinphenyl)sulfones and bisphenols of formula I as described above are used, but 9. The amounts used by IL et al. are as follows.

The amount of bis(hydroxyphenyl)sulfones used for the dicarboxylic acid component is 0 per mole of dicarboxylic acid.
The range is from 36 to 1.06 mol, preferably from 0.40 to 10 mol, particularly preferably from 0.45 to 096 mol.

Further, the amount of bisphenols of formula I to be used with respect to the dicarboxylic acid component is 0.04 to 0.04 to 1 mole of dicarboxylic acid.
066 moles, preferably in the range of 008 to 062 moles.

Furthermore, bis(hydroxyphenyl)sulfonos and formula I
The total amount of bisphenols in the dicarboxylic acid component ranges from 090 to 110 monos(σ) per mole of the dicarboxylic acid component.

If the amounts of bis(hydroxyphenyl)sulfonos and bisphenols of formula I are used outside the above ranges, the properties of the resulting polymer will be impaired.

For bis(hydroxyphenyl)sulfone, the number of bis(hydroquinphenyl)sulfone residues per dicarboxylic acid residue in the polymer is less than 0.36;
Heat resistance tends to be poor, and conversely, when more than 10 6 are present, problems tend to occur in the moldability of the polymer, the transparency and toughness of the molded product, etc.

Regarding bisphenols of formula I, if the number of bisphenol residues per dicarboxylic acid residue in the polymer is less than 004, the polymer will have poor moldability, molded product toughness, transparency, etc. It is easy to get enough (on the contrary, if it exceeds 066, the property against heat deteriorates.

The aromatic polyester used in the present invention has a logarithmic viscosity ηinh of 02 to 2.0 as determined by the measuring method described below.
, preferably in the range of 03-08.

There are no particular restrictions on the method for producing the aromatic polyester used in the present invention, and any known method can be applied, but typical polymerization methods include the following method.

That is, bis(hydroxyphenyl) sulfones and bisphenols of formula (2) are dissolved in an aqueous phase together with an alkali metal hydroxide, and inphthaloyl chloride and/or terephthaloyl chloride are dissolved in a water-insoluble organic solvent. , an interfacial polymerization method in which both phases are mixed and reacted; bis(hydroxyphenyl) sulfones, bisphenols of the formula (■), inphthaloyl chloride and/or terephthaloyl chloride are made into a homogeneous organic solvent solution, and the third is used as a dehydrochlorination agent. Typical examples include solution polymerization in which a diester of isophthalic acid and/or terephthalic acid is melt-reacted with bis(hydroquinphenyl)sulfones and bisphenols of formula I. This is a great method.

The aromatic polyester molded article used in the present invention can be obtained using any molding method such as injection molding, extrusion molding, compression molding, and rotational molding. In addition, in the present invention, talc, carunium carbonate,
Aromatic polyester resin molded products mixed with various fillers such as glass fiber and carbon fiber can also be used.

In the present invention, low-temperature plasma is non-equilibrium plasma obtained by activating gas molecules by high-frequency discharge, microwave discharge, or the like.

In general, plasma is generated due to the relationship between the energy of electrons and the energy of ions and unionized neutral gas particles.
It is classified into equilibrium plasma and non-equilibrium plasma. The former is plasma when the gas pressure is relatively low, as seen in arc discharge, and the collisions between electrons and ions and gas particles are intense, so sufficient energy exchange occurs, and the two have approximately the same energy. It is in an equilibrium state and is also called a thermal plasma. On the other hand, the latter is a plasma when the gas pressure is low, and because there are few collisions, the electrons with small mass are mainly accelerated by the external electric field, and the energy of the electrons is greater than that of ions or gas particles. It is in a non-equilibrium state. This nonequilibrium plasma is the low-temperature plasma used in the present invention, and the temperature of gas particles and ions is between room temperature and
Although it is as low as 8 degrees at 800 degrees, the energy of the electrons, or temperature, is high, reaching tens of thousands of degrees or more.

The low-temperature plasma treatment is performed by placing the molded article in a plasma atmosphere of oxygen or the like generated under a gas pressure of about 01 to 1.0'J,'orr. Oxygen is preferable as the gas for generating plasma, but air may also be used economically. In carrying out the present invention, the plasma treatment time is preferably about 5 seconds to 1 minute; if the treatment time is too long, the reforming effect will not improve and it will be uneconomical.

The surface of the aromatic polyester resin molded product treated by the treatment method of the present invention has increased hydrophilicity and has improved affinity with paints, printing inks, adhesives, etc., and can be used for painting, printing, etc. as is.
Secondary processing such as adhesion, chemical plating, metal vapor deposition, and sputtering can be performed.

The present invention will be specifically explained below using Examples.

In the following examples, the logarithmic viscosity 1-branch η Koura is determined by the following formula using a mixed solvent of phenol/tetrachloroethane (weight ratio 6/4) and a 0.5 f/d7 solution.

tl ηinh knee tone - Ct.

(In the above formula, t□ is the flow time of the polymer solution, tl is the flow time of only the solvent, and C is the polymer solution concentration (9/
dt).

Examples 1 to 3 and Comparative Example 1 Bis(4-hydroxyphenyl)surbot 3.5Kg (
14 mol), 2,2-bis(4'-hydroxyphenyl)furobane 1.37 Ky (6 mol) and 0-phenylphenol 238? (1.4 mol) were placed in a reactor, and 2% hydroxylated ) 88 t of IJium aqueous solution was added and dissolved, and the mixture was cooled to 10°C. A stream of N2 was passed through the solution for 30 minutes, and 1:1 of cetyltrimethylammonium furomite was added. Inphthaloyl chloride and terephthaloyl chloride (1: 1) mixture 4., 20 N9
(20.7 mol) 'r A solution dissolved in dichloromethane 601 was added all at once to the solution in the above-mentioned reactor which was kept at 10'C and stirred, and stirring was continued for 1 hour while keeping it at 10'C. A sample of the reaction solution was analyzed using Gel E perchromatography for low molecules, and no unreacted molemer was found. Next, 3 tons of IN hydrochloric acid aqueous solution was added, followed by 30 tons of water, stirred and left to stand to separate the lower layer, which was further washed twice with 30 tons of water.

The washed dichloromethane layer was added to 120 tons of methanol under high speed stirring using a homomixer to precipitate a polymer. The precipitated colorless polymer was separated, further washed with methanol, and dried to obtain a polymer powder weighing 7431<g.

The logarithmic viscosity of the obtained polymer was 054, and NMR,
From the spectrum, the abundance ratio of bis(/I-hydroxyphenyl) sulfone residue and 2,2-bis(4'-hydroxyphenyl)propane residue in the polymer was approximately 7:3.

The aromatic polyester resin thus obtained was molded into a flat plate of 80 x 50 mm and 2 mm thick using an injection molding machine. This flat plate was subjected to low temperature plasma treatment under the following conditions.

(1) Plasma processing equipment Tokyo Shibaura Electric Co., Ltd. Microwave plasma processing equipment TMW-0407B-VPG (2) Plasma processing conditions Microwave output 800 W Gas body Oxygen gas pressure I Torr Processing time 0.5.30.60 seconds In order to examine the hydrophilicity of the surface of the treated product, the wettability index was measured using a wettability index standard solution for wetness tests. The results are shown in Table 1.
The wettability index of the low-temperature plasma treated product is higher, indicating that the hydrophilicity has been improved. This exam is 18T1>
1-D-2578.

Table 1 Length Example 4 and Comparative Example 2 A flat plate of 80 x 50 mm and 2 fins thick was molded using an injection molding machine from the aromatic polyester resin obtained in Example 1, and the processing times were 0 seconds and 30 seconds. After performing low-temperature plasma treatment under the same conditions as in Example 1, a conductive paint product manufactured by Fujikura Kasei (named Daughter()-D-500) was applied to a thickness of 20 μm. After sufficiently drying, the coated film surface was cut into 100 squares of 1 square inch, and the squares on the coated film surface were peeled off using Sellotape, and the peeled squares were measured. The results are shown in Table 2, and it is clear that the low-temperature plasma-treated product had no peeling of squares σ), and that the coating film adhesion was improved.

Claims (1)

[Claims] (1) Is it a structural unit represented by the following formulas A, B, and C?
Therefore, the ratio of the number of structural units A to the number of structural units B is 1:
0.36 to 1.06, and the number of structural units A and structural unit C
The ratio to the number of structural units A is 1:0.04 to 0.66, and the ratio of the number of structural units A to the sum of structural units B plus C is 1:0.
．． 90-1.10 and the logarithmic viscosity of the polymer is 02-1.10.
2.0 [However, in the above formula, in Takejin, the carbonyl groups are in the meta or para position to each other, and in 2B, the oxygen atom is SO
! The oxygen atom is in the meta or para position relative to the group; X in formula C is a divalent hydrocarbon group having 1 to 10 carbon atoms, 0, C
O, S, SO or so. and a is O or 1. R1 to R4 each represent hydrogen, a hydrocarbon group having 1 to 8 carbon atoms, or a halogen atom, and may be the same or different, but when X is SO, all of ~R, are hydrogen at the same time. A method for surface treatment of resin molded articles, characterized by treating the surface of the molded article obtained from [1] with low-temperature plasma.