JPH07126420A - Method for forming film of polyp-xylenene onto surface of polymeric molding - Google Patents

Abstract

PURPOSE:To carry out the formation of a polyp-xylylene film excellent in adhesion on the surface of a polymeric molding by depositing and polymerizing the poly-xylylene in the vapor phase on the surface of the specific polymeric molding. CONSTITUTION:This method for forming a film of polyp-xylylene on the surface of a polymeric molding is to mix a polymeric resin to be a substrate for the molding with preferably 0.1-50 pts.wt. polysiloxane-modified thermoplastic resin such as a graft copolymer of a polysiloxane compound and a thermoplastic resin, providing a polymeric resin composition, then molding the resultant polymeric resin composition and depositing and polymerizing the polyp-xylylene expressed by the formula (n is >=5000) in the vapor phase on the surface of the prepared polymeric molding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a polyparaxylylene film capable of firmly adhering a vapor-deposited polyparaxylylene film onto the surface of a polymer molding. Specifically, it is possible to realize a practical adhesion between the polymer molded product and polyparaxylylene without subjecting the polymer molded product to complicated surface treatment. As a result, permeation of gas from the outside,
In addition, the characteristic of polyparaxylylene coating is that it has less gas emission from the inside, has lubricity by itself without using lubricants such as oil and grease, and has excellent chemical resistance. Can be easily, safely and inexpensively obtained. The polymer molded article coated with polyparaxylylene according to the present invention is for general household use,
It can be widely used for OA, electric and electronic equipment fields, automobile fields, construction fields, medical fields, sports fields, and the like.

[0002]

2. Description of the Related Art Polymer compounds are synthetic rubbers, synthetic fibers,
It can be roughly divided into synthetic resins (plastics) and has physical and chemical characteristics that low-molecular compounds do not have, and is characterized by being particularly tough relative to its weight, and is currently used in various fields. It is used for purposes.

[0003] These polymer compounds have various additives, pigments, curing agents, in addition to various kinds of raw material compounds.
Since it can be added with various properties by being added to polymer compounds such as curing accelerators, it can be used in a wide range of fields such as general households, automobiles, electric industry, medicines, and sports. There is.

On the other hand, the vapor-deposited polymerized film of polyparaxylylene has an electric insulating property higher than that of silicone, epoxy, urethane, etc., is insoluble in all organic solvents at a temperature of 150 ° C. or lower, and is almost free of acids and alkalis. Even if it is not corroded, it can withstand continuous use for 10 years at 200 ° C or higher under vacuum and an inert gas atmosphere, and it will not be damaged by bending at 180 ° even at a low temperature of -150 ° C. Due to its exceptional properties such as cold resistance, permeability and precision in narrow gaps of micron order, gas barrier property with extremely low permeability of water vapor and gas, and excellent outgas barrier property from adherend, It has been used in the fields of precision electrical and electronic, space, automobile electrical equipment, physics and chemistry equipment, cultural property preservation, etc.

In addition, the vapor-phase vapor-deposited polymerized film of these polyparaxylylenes can be conformally coated without pinholes due to the thickness of 0.2 μm depending on the adherend, and the adherend during coating. A major feature is that no coating strain remains because no heat history is applied to the.

These polyparaxylylene vapor-phase vapor deposition polymerized coatings can be coated on various materials because there are a wide variety of adherends to be selected depending on the processing method. However, among these adherends, for those with poor adhesion of the vapor-deposited polyparaxylylene film, the conventional coupling agent, corona discharge, plasma treatment, ozone cleaning, acid treatment, surface treatment A method of applying a physical or chemical treatment such as roughening has been used. Other U.S. Pat. No. 3,600,216
Publication No., No. 4784881, Publication No. 58-563
71, JP-A-1-168859, etc., discloses a technique relating to a method for improving the adhesion of a vapor-deposited polymerized film of polyparaxylylene to an adherend.

[0007]

[Problems to be Solved by the Invention] It is suggested that an ultra-high functional polymer molded product can be obtained by combining a polymer molded product and a polyparaxylylene film. Since it is extremely stable, the adhesion to the adherend is generally not preferable in many cases. In addition, it is not possible to follow the elasticity, elongation, bending, etc. of the polymer resin that is the base material, and when a polyparaxylylene coating is formed on these, it is generally easy to apply the coating with adhesive tape or the like. It can be peeled off, and depending on the type of polymer resin, even a slight bend may cause peeling.

Generally, in order to improve the adhesion, it is effective to apply a physical or chemical treatment such as a silane coupling agent, corona discharge, plasma treatment, ozone cleaning, acid treatment and surface roughening. However, they are not effective for all adherends. Furthermore, many of these treatments are complicated in operation, and not only are they subjected to physical and chemical changes depending on the kind of the base polymer resin,
There is a drawback in that the facility itself, its associated equipment, or a huge cost is required for operation.

In addition to these treatment methods, various methods have been proposed for improving the adhesion of the vapor-deposited polymer film of polyparaxylylene to the adherend. Specifically, US Pat. No. 3,600,216 discloses a method of using a silicon compound containing an ethylenically unsaturated group and a hydrolyzable group as a primer. However, the surface treatment with the primer and other various coupling agents requires complicated steps, and in order to improve adhesion, the coupling agent solution before treatment, the treatment method, the drying method, and the deposition after treatment are required. Strict management in terms of process and time in the body etc. is required.

US Pat. No. 4,784,811 discloses a method of forming a vapor-deposited polymerized film of polyparaxylylene after treating an adherend with a phosphoric acid unsaturated ester, but the process is complicated. In addition, in order to improve the adhesiveness, it is necessary to strictly control the treatment agent before treatment, the treatment method, the curing method, and the adherend after treatment in terms of steps and time. This is the same as when a silicon compound is used.

Japanese Patent Publication No. 58-56371 discloses that a silane coupling agent containing an ethylenically unsaturated group and a hydrolyzable group is introduced into a vapor deposition chamber of polyparaxylylene at the same time as an adherend, and By applying a coating process of polyparaxylylene under normal depressurization conditions, the adhesiveness to the adherend due to the coupling agent vapor is improved, and it is a vapor deposition polymerization method of polyparaxylylene. There are various methods, and the shape of the deposition chamber, the efficiency, the allowable adherend amount, etc. are different depending on the method. Therefore, it is very difficult to find the optimum adhesion improvement method using this method, and The inside of the deposition chamber is also contaminated by the ring agent.

Japanese Unexamined Patent Publication (Kokai) No. 1-168859 discloses a method of irradiating ultraviolet rays after forming a vapor-phase vapor deposition polymerized film of polyparaxylylene on an adherend. However, this method, which can be easily inferred from the chemical structural formula of polyparaxylylene, turns yellow due to ultraviolet rays, and because the adherend is also affected by very large ultraviolet energy and heat and ozone. , Especially polymer molded products that use polymer resin that contains a double bond in the molecule and is easily deteriorated by ultraviolet rays and ozone, and chemicals such as UV absorbers and ozone resistance improvers. It is not always the best method for polymer moldings not added.

[0013]

[Means for Solving the Problems] The inventors have made various studies on the improvement of the practical adhesion of these polyparaxylylene to the surface of a polymer molded product. When a polymer molded product obtained by mixing a modified thermoplastic resin and molding with the polymer resin composition is formed into a film with polyparaxylylene, the adhesion between the polymer molded product and the polyparaxylylene coating is The inventors have found that it is remarkably improved and have reached the present invention.

[0014]

DETAILED DESCRIPTION OF THE INVENTION Polymer resins can be roughly classified into synthetic rubber, synthetic fiber, synthetic resin (plastic) and the like, and each has physical and chemical characteristics not found in low molecular weight compounds. It is characterized by being relatively strong, and is currently used for various purposes in all fields.

As the polymer resin used in the present invention,
It has been widely used in the past, and a polymer resin for carrying out the present invention can be selected according to hardness, strength, elongation, color, and electrical characteristics depending on the required performance, and its type is not particularly limited. .

For example, in synthetic rubber, isoprene rubber, butadiene rubber, styrene butadiene rubber, chloroprene rubber, nitrile rubber, butyl rubber, ethylene propylene rubber, chlorosulfonated polyethylene, acrylic rubber, epichlorohydrin rubber, polysulfide rubber, silicone rubber, fluorine Rubber, urethane rubber, propylene oxide rubber, ethylene-vinyl acetate copolymer and the like can be used.

Among synthetic fibers, polyamide-based, polyester-based, polyurethane-based, polyurea-based, polystyrene-based, polyvinyl chloride-based, polyvinylidene chloride-based, polyacrylonitrile-based, polyfluorinated ethylene-based, polyvinyl alcohol-based synthetic fibers, etc. Can be used.

Among synthetic resins (plastics), phenol resin, urea resin, melamine resin, epoxy resin, polyurethane, alkyd resin, furan resin, thermosetting resin such as unsaturated polyester, vinyl chloride resin, polyvinyl alcohol, polystyrene, ( A thermoplastic resin such as (meth) acrylic resin, ABS resin, polyethylene, polypropylene, fluororesin, polysulfone, saturated polyester, polyamide, and celluloid can be used.

The polysiloxane-modified thermoplastic resin used in the present invention is obtained by graft-polymerizing a reactive polyorganosiloxane on the thermoplastic resin. A compound used for modifying the polymer compound or as a compatibilizing agent for the polymer compound and the polysiloxane resin can also be used in the present invention.

The polysiloxane-modified thermoplastic discharge resin of the present invention is disclosed, for example, in JP-A-58-126378 and JP-B-59-.
39723, JP-A-60-252613, JP-B-62-
9127, Japanese Patent Laid-Open No. 1-278533 and the like disclose basic concepts, manufacturing methods, application examples and the like.

In the polysiloxane-modified thermoplastic resin of the present invention, the base thermoplastic resin is ethylene- (meth) acrylic acid copolymer, ethylene- (meth)
Methyl acrylate copolymer, ethylene- (meth) acrylate acrylate copolymer, ethylene- (meth) propyl acrylate copolymer, ethylene- (meth) acrylate butyl copolymer, ethylene-α-olefin copolymer Examples thereof include polymer, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polyethylene, polystyrene and the like. The polysiloxane-modified thermoplastic resin used in the present invention is obtained by graft polymerization of these thermoplastic resins and reactive dimethylpolysiloxane or reactive modified polysiloxane. In the present invention, the polysiloxane-modified thermoplastic resin is conveniently selected in consideration of compatibility with the polymer resin of the base material, physical properties of the resin molded product after molding, and the like.

The basic structure, production method, polymerization method, etc. of the polyparaxylylene used in the present invention are described in US Pat. No. 3,379,803, JP-B-44-21353, JP-B-45-31787, and JP-B-52-52. The compounds having the following chemical structural formulas are specifically disclosed in 37479 and the like.

[0023]

[Chemical 1]

[0024]

[Chemical 2]

[0025]

[Chemical 3]

[0026]

[Chemical 4]

[0027]

[Chemical 5]

[0028]

[Chemical 6]

(Where n is an integer of 5,000 or more) and the like, and may be used alone or in combination. )

Polyparaxylylene is formed by a vapor phase vapor deposition polymerization method, and its vapor deposition mechanism is composed of three steps. That is, the first step in which the solid dimer of the raw material, diparaxylylene (A), is vaporized, the second step in which the diradical paraxylylene (B) is generated by the thermal decomposition of the dimer, the diradical to the adherend. High-molecular-weight polyparaxylylene (C), which is simultaneously adsorbed and polymerized with paraxylylene
Is the third step in which film formation occurs.

For example, the reaction formula of the chemical formula (1) in these three steps is as follows.

[0032]

[Chemical 7]

In this process, the degree of vacuum is generally 10
^{-3 to 1} Torr, the first step is 100 to 200
C., the second step is performed at 450 to 700.degree.

The polyparaxylylene coating film obtained by the vapor deposition polymerization method can be conformally coated on the adherend, and since the coating is performed at room temperature, the adherend is adhered. It also has features on the processing surface such as not giving a heat history to.

In the present invention, the polyorganosiloxane-modified thermoplastic resin is added in the same manner as the addition of various additives such as an antioxidant, an ultraviolet absorber and a pigment in the usual process for producing a polymer molding. Yes, usually the amount added is
It depends on the siloxane content in the polyorganosiloxane-modified thermoplastic resin. It is about 0.1 to 50 parts by weight, preferably about 1 to 20 parts by weight, based on the raw material resin. If the addition amount is less than this, the adhesion of the polyparaxylylene coating formed on the surface to the substrate cannot be improved to a practical level, and if the addition amount is more than this, the performance of the molded article itself is adversely affected. . Further, even when the polymer resin as the base material of the polymer resin molded product is a mixed composition with the polysiloxane resin, the polyorganosiloxane-modified thermoplastic resin is mixed with the polymer resin and the polysiloxane resin. Also for the purpose of using as a compatibilizer, the amount of the polyorganosiloxane-modified thermoplastic resin added is preferably kept in the above range in the present invention.

In the production of polymer moldings, various additives such as anti-aging agents, plasticizers, heat stabilizers, UV absorbers, pigments, etc., fillers, stabilizers, etc. may be appropriately mixed, or if necessary. Depending on the kind of so-called polymer alloy or polymer blend obtained by reacting or blending different kinds of polymer materials, if the required amount of the polysiloxane-modified thermoplastic resin of the present invention is added, adhesion of polyparaxylylene on the surface Sex improves to a practical level.

Further, in the present invention, a coupling agent, corona discharge, plasma treatment, which is a conventional adhesion improving method,
Physical or chemical treatment such as ozone cleaning, acid treatment, and surface roughening may be performed.

[0038]

EXAMPLES The present invention will now be described in more detail with reference to examples, but these do not limit the use of the present invention. All "parts" used in this example are "parts by weight".
Indicates.

Silgraf 150 (manufactured by Nippon Unicar Co.) and SP-300 were added to various rubber materials having the compositions shown in Table 1.
Two types of siloxane-modified thermoplastic resins (manufactured by Dow Chemical Co.) were added to the base polymer in amounts of 5 and 10, respectively.
A rubber sheet, which was partly kneaded and heat-pressed to a thickness of 2 mm, was cut into a size of 25 × 100 mm to prepare a test piece.

[0040]

[Table 1]

Polyparaxylylene was vapor-deposited on the above test piece under the conditions shown in Table 2 and a 180 ° peeling test using cellophane adhesive tape (manufactured by Toyo Kagaku Co., Ltd. (condition: pulling speed = 200 mm / min). ), And a cross-cut test.
For comparison, the rubber material of Table 1 was also subjected to the same test with respect to the rubber material to which the siloxane-modified thermoplastic resin was not added to evaluate the adhesion.

[0042]

[Table 2]

The results of the peel strength test using the sylgraft 150 and the adhesive strength evaluation by the cross cut test are shown in Table 3 and SP-
It is shown in Table 4 using 300. In addition, "**" in the table
Indicates that the polyparaxylylene coating was not peeled off.

[0044]

[Table 3]

[0045]

[Table 4]

【effect】

As described in detail above, when a polyparaxylylene film is formed on the surface of a polymer molding, the method according to the present invention does not require any complicated surface treatment or the like on the polymer molding. Thus, it becomes possible to obtain a practical adhesive force between the polymer molding and polyparaxylylene. As a result, there is little permeation of gas from the outside and release of gas from the inside, and it has lubricity by itself without the use of a lubricant such as oil or grease, and it has characteristics such as excellent chemical resistance. The paraxylylene film can be formed on the surface of the polymer molded product easily, safely and inexpensively. The obtained polymer molded product with a polyparaxylylene film is used in an extremely wide range of fields such as general household use, OA, electric and electronic equipment fields, automobile fields, construction fields, medical fields, sports fields, etc. It is useful.

Claims (2)

[Claims] 1. When forming a vapor-deposited polymerized film of polyparaxylylene on the surface of a polymer molding, a high molecular weight resin is prepared by mixing a polysiloxane-modified thermoplastic resin with a polymer resin as a base material of the molding. A polymer characterized by obtaining a molecular resin composition, then molding with the polymer resin composition, and forming a film of polyparaxylylene on the surface of the obtained polymer molded product by a vapor phase vapor deposition polymerization method. A method for forming a film of polyparaxylylene on the surface of a molded product. 2. The polysiloxane-modified thermoplastic resin is a graft copolymer of a thermoplastic resin and a polysiloxane compound, and the polysiloxane-modified thermoplastic resin is used as a base polymer resin in an amount of 0.1 to 50 parts by weight. Molded with the polymer resin composition in which parts are mixed.
For forming a polyparaxylylene coating on the surface of a polymer molded article of the above.