JP2012206316A - Hard vinyl chloride base material covered with metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hard vinyl chloride base material covered with a metal, which includes a metal coating with excellent durability to high temperature and high humidity and adheres firmly to the surface of the base material composed of the hard vinyl chloride, without performing a solvent-based undercoat or primer treatment.SOLUTION: This hard vinyl chloride base material covered with a metal is covered with a metal film layer by vapor deposition through the surface modified layer of the base material, the surface modified layer being arranged on the surface of the base material composed of the hard vinyl chloride. The surface modified layer preferably includes at least a carboxyl group as a functional group. The surface modified layer is preferably formed by an atmospheric pressure plasma treatment using a nitrogen gas as the reaction gas.

Description

  The present invention relates to a hard vinyl chloride substrate having a metal thin film. More specifically, a hard chloride with a metal film that adheres firmly to the surface of a hard vinyl chloride substrate and has excellent durability against high temperatures and high humidity without undercoating or primer treatment with an organic solvent. A resin film, a resin sheet, and a resin plate made of vinyl are provided.

  Generally, a vinyl chloride resin in which about 10 to 60% of a plasticizer is blended is called a soft vinyl chloride resin (soft vinyl chloride), and a phthalate ester is generally used as the plasticizer. A vinyl chloride resin not containing a plasticizer is called a hard vinyl chloride resin (hereinafter sometimes abbreviated as hard vinyl chloride or hard PVC).

  Conventionally, hard PVC has the advantage of being inexpensive and lightweight, and has been used as a structural material for water pipes, rain gutters, window frames and the like. Moreover, hard vinyl chloride is excellent in corrosion resistance and chemical resistance against most strong acids, weak acids, alkalis, salts, and animal and vegetable oils, and has electrical insulation properties inferior to phenolic resins. Hard vinyl chloride is relatively hard and has a property of being easily cracked, has poor heat resistance, and has a use temperature of at most 80 ° C.

  The thing which vapor-deposited the metal on the surface of hard vinyl chloride, and coat | covered the metal thin film is used for various uses. For example, a faucet (shower head) for a hot water shower uses a plastic exterior body to prevent burns, specifically, a hard vinyl chloride vapor-deposited aluminum. Or the mirror produced by vapor-depositing aluminum on the surface of the thin sheet | seat of hard vinyl chloride is also used as a lightweight and safe mirror replaced with glass.

By the way, forming a metal vapor deposition film | membrane on the surface of synthetic resin films, such as hard vinyl chloride, is performed conventionally, for example, is shown by patent documents 1-3.
Patent Document 1 discloses a building panel body in which a laminate in which an aluminum layer is formed by vapor deposition on a synthetic resin film. Here, polyester, hard vinyl chloride, and the like can be used as the synthetic resin film, but nothing is described about surface modification of the synthetic resin film.
Patent Document 2 discloses a biaxially stretched film such as a biaxially stretched polyester film, a biaxially stretched polypropylene film, a biaxially stretched nylon film, a rigid vinyl chloride film, a polyvinyl alcohol film, or a polymethyl acrylate film as a transparent film. A double-sided light-shielding film having a metal vapor-deposited layer on one side of a film that is not biaxially stretched and the like and having a white print on both sides of the transparent film with the metal vapor-deposited layer is disclosed. In Patent Document 2, there is a description that “a chemical treatment such as corona treatment, plasma treatment, and coating of an adhesive on the surface layer may be performed in order to improve vapor deposition adhesion of aluminum or the like” There is no specific description of the chemical treatment.
In Patent Document 3, a modified layer is formed on one side of a transparent resin film by low-temperature plasma treatment or corona discharge treatment, and an adhesive resin layer and an infrared reflective layer are sequentially laminated on the modified layer. A transparent insulating material is disclosed. However, as the transparent resin film, fluorine-containing resins such as polyvinyl fluoride, olefin resins such as polypropylene, acrylic resins such as polymethyl acrylate, and polyester resins such as polyethylene terephthalate can be used. There is no description.

Japanese Patent Laid-Open No. 11-117419 Japanese Unexamined Patent Publication No. 04-052135 Japanese Patent Publication No. 06-028938

  However, the metal-deposited thin film formed on the surface of hard vinyl chloride according to the prior art has a problem that its use is limited because it cannot obtain a durable material that can withstand a high temperature and high humidity environment.

  An object of the present invention is to provide a metal film having a metal film having excellent durability against high temperature and high humidity by firmly adhering to the surface of a substrate made of hard vinyl chloride without performing a solvent-based undercoat or primer treatment. It is to provide a coated rigid vinyl chloride substrate.

In order to solve the above-mentioned problems, the present invention provides a surface modification layer on the surface of a substrate made of hard vinyl chloride, and a metal thin film layer formed by vapor deposition is coated through the surface modification layer of the substrate. A metal-coated hard vinyl chloride substrate is provided.
The surface modification layer preferably contains at least a carboxyl group as a functional group.
The surface modification layer is preferably formed by atmospheric pressure plasma treatment using nitrogen gas as a reaction gas.
The metal thin film layer includes at least one selected from the group consisting of aluminum, copper, nickel, chromium, gold, silver, platinum, tin, zinc, metal oxide, and metal oxide. Is preferred.
It is preferable that the base material is any one selected from the form of a resin film, a resin sheet, and a resin plate.

  According to the present invention, a metal having a metal film that is firmly bonded to the surface of a substrate made of hard vinyl chloride and has excellent durability against high temperatures and high humidity without performing a solvent-based undercoat or primer treatment. A coated rigid vinyl chloride substrate can be provided.

Hereinafter, the present invention will be described based on preferred embodiments.
In the metal-coated hard vinyl chloride substrate according to the present invention, a surface modification layer is provided on the surface of a substrate made of rigid PVC, and a metal thin film layer by vapor deposition is formed through the surface modification layer of the substrate. Covered. Examples of the method for forming the surface modified layer of the hard PVC substrate include corona discharge treatment (air corona treatment) in an air atmosphere, corona discharge treatment in a nitrogen gas atmosphere, and atmospheric pressure glow plasma treatment.

(Corona discharge treatment)
The surface modification treatment by corona discharge generates corona discharge in the atmosphere using a high-frequency power supply voltage, and irradiates the surface of the resin substrate with electrons and ions generated along with it. The surface modification of the resin base material is performed by adding a group.
In the surface modification treatment by corona discharge performed in an air atmosphere, the surface of the resin substrate subjected to the corona discharge treatment is oxidized, and on the surface of the resin substrate, a carbonyl group ( It is thought that oxygen functional groups such as> CO) and carboxyl groups (—COOH) are mainly formed.

(Corona discharge treatment in nitrogen gas atmosphere)
In addition, by performing corona discharge treatment in a nitrogen gas atmosphere and using nitrogen gas as a reaction gas, amino groups (-NH) that are thought to contribute to adhesion to the main chain and side chain of the polymer on the surface of the resin substrate. _It is thought that nitrogen functional groups such as ₂ ) are mainly generated. Furthermore, unlike corona discharge treatment (air corona treatment) in a normal air atmosphere, corona discharge treatment in a nitrogen gas atmosphere causes discharge in a nitrogen gas atmosphere, so corona discharge treatment (air corona discharge in an air atmosphere). The generation of a fragile layer due to impurities in the air generated when the treatment is performed is suppressed. Some patent documents describe that nitrogen gas can also be used as an atmospheric gas for atmospheric pressure glow plasma treatment, but it is not atmospheric pressure glow plasma discharge when the discharge state is observed. However, corona discharge in a nitrogen gas atmosphere is capable of lightning-like streamer-like (linear) lightning, that is, a gentler (mild) glow discharge than corona discharge in an air atmosphere by adjusting discharge conditions. Therefore, it can be used for surface modification that is more uniform than air corona treatment.

(Atmospheric pressure glow plasma treatment)
Conventionally, low-temperature plasma treatment for discharging in a vacuum state has been used for surface modification. However, since vacuum equipment is required, there is a drawback that the apparatus becomes large and the operation is complicated. For this reason, an atmospheric pressure plasma treatment apparatus that generates a glow discharge state that can only be generated in a vacuum state at atmospheric pressure and performs surface modification using the reaction radicals, electrons, etc. generated by the glow discharge state is usually It has come to be used simply for improvement and adhesion improvement.

  Atmospheric pressure glow plasma treatment uses a rare gas element such as helium or argon as the atmosphere gas to maintain a stable glow discharge, which is more streamer-like (linear) like lightning, that is, more than corona discharge in an air atmosphere. Uniform surface modification without unevenness is possible. Some patent documents describe that nitrogen gas can also be used as an atmospheric gas for atmospheric pressure glow plasma treatment, but it is not atmospheric pressure glow plasma discharge when the discharge state is observed.

The atmospheric pressure plasma treatment in the present invention is a corona discharge treatment in a nitrogen gas atmosphere or an atmospheric pressure glow plasma treatment in a rare gas atmosphere such as helium or argon, which reacts with nitrogen gas, oxygen gas, carbon dioxide gas, or the like. It can be gas.
In atmospheric pressure plasma treatment using oxygen gas as a reaction gas, oxygen functional groups such as carbonyl groups (> CO) and carboxyl groups (—COOH) are mainly formed on the main chain and side chains of the polymer on the surface of the resin film. To do. Further, by using nitrogen-based gas as a reaction gas, for example, N ₂ , N ₂ O, NH _3, etc., and further mixing hydrogen (H ₂ ), oxygen (O ₂ ), etc., amino groups, amide groups, etc. The present inventors have confirmed that it can be intentionally introduced.
Further, CH ₄ , CO ₂ or the like may be added to the reaction gas. When carbon dioxide (CO ₂ ) is used as a reaction gas, weak oxidation occurs on the surface of the substrate, and oxygen functional groups are mainly generated.

In consideration of these, in the present invention, when the surface modification treatment is performed on the surface of the rigid PVC substrate using the atmospheric pressure plasma treatment, the corona discharge treatment in a nitrogen gas atmosphere or the rare gas atmosphere such as helium or argon is used. The atmospheric pressure glow plasma treatment is preferably used. Further, it is preferably formed by atmospheric pressure plasma treatment under a nitrogen gas atmosphere.
Further, in the present invention, in the atmospheric pressure plasma treatment, the surface of the resin film is irradiated with the plasma generated by the atmospheric pressure plasma treatment apparatus so that the adhesive modified layer is formed on the surface of the rigid PVC substrate. Adjust the time, applied power, frequency, etc.
The surface modification layer preferably contains at least a carboxyl group (—COOH) as a functional group. As a result, the adhesion to metal (partial peeling, adhesion to the entire film) becomes higher.

Examples of the metal constituting the metal thin film layer or a compound thereof include aluminum (Al), copper (Cu), nickel (Ni), chromium (Cr), gold (Au), silver (Ag), platinum (Pt), tin ( Examples thereof include metals such as Sn) and zinc (Zn), alloys of these two or more metals, or metal oxides and alloys containing metal oxides. Examples of the metal oxide include TiO ₂ , CrO _x , ITO (indium-added tin oxide), FTO (fluorine-added tin oxide), ATO (antimony-added tin oxide), ZnO, Al ₂ O ₃ , SiO _{x and the} like.
The metal thin film layer has electrical conductivity, thermal conductivity, designability (coloring and metallic luster imparting), moisture resistance, airtightness, visible light reflectivity (light-shielding property), electromagnetic wave shielding properties (infrared heat insulation and electromagnetic waves) It can be used for various purposes such as shielding.

  Formation of the metal thin film layer includes vapor deposition of metal, alloy, metal oxide, etc., sputtering, coating, sticking of metal foil, and the like. Since the surface modified layer has high wettability and good adhesion to metal, the metal thin film layer can be laminated without applying an adhesive and an anchor coating agent to the surface of the substrate. The metal thin film layer can be formed over the entire surface of the substrate or can be formed partially.

Further, the thickness of the base material made of rigid PVC is not particularly limited, but the shape of the surface for laminating the metal thin film layer is preferably a certain degree of flatness due to the surface modification treatment. . For example, a resin film, a resin sheet, a resin plate, etc. are mentioned.
The metal-coated rigid PVC base material of the present invention can be used to form a composite material by laminating with other kinds of base materials such as resin films such as polyolefin, nylon and polyester, paper and cellophane.
The metal-coated rigid PVC substrate according to the present invention can be used in various applications such as a decorative sheet, an optical film, a protective film, a member for electronic / OA equipment, a medical member, and a packaging container.

Hereinafter, the present invention will be specifically described with reference to examples.
(Test method)
Initial adhesion was performed by a cross-cut tape test according to JIS K 5400 (or its revised version, JIS K 5600-5-6). That is, a cut is made at intervals of 1 mm on the surface of the substrate on which the deposited film layer is formed using a knife, and 100 squares of 1 mm 2 are formed. Next, heserohan adhesive tape (trade name “Cellotape (registered trademark)” manufactured by Nichiban Co., Ltd.) was strongly pressed, and then suddenly pulled away from the surface in the direction of 90 °, and then the deposited film layer remained. The state was observed visually.
In the high-temperature and high-humidity storage test, the specimen is left for a predetermined time in an environment of 40 ° C. × 90% RH or 60 ° C. × 90% RH, and then JIS K 6854-1 “Adhesion” The peel strength (N / 25.4 mm) was measured by the measurement method defined in “Method of peeling adhesive strength test method Part 1: 90 degree peeling”.

The state of the vapor deposition film layer at the time of peeling was classified according to the following criteria depending on how the interface between the hard PVC base material and the metal vapor deposition film layer was peeled off.
・ Overall peeling ・ ・ ・ ・ When the deposited film layer is completely peeled from the substrate.
-Partially peeled off ... When the deposited film layer peeled off at a rate of 10% or more.
・ Partially peeled: When the deposited film layer peels at a rate of less than 10%.
-Vapor deposition cracks ... When a crack occurs in the vapor deposition film layer and the adhesion of the thin vapor deposition film layer to the peeling film (cellophane adhesive tape or L-LDPE) side is visually confirmed.
-No description ... When no peeling or cracking of the deposited film layer was visually confirmed (good).
・ Stage peeling ・ ・ ・ ・ ・ ・ ・ When the vaporized film layer peels off from the base material and the part where it does not peel appears alternately in multiple stages in the pulling direction.

In the table showing the results of the initial adhesion, “◯” was evaluated when not described (good), and “x” was evaluated otherwise.
In the results of the high temperature and high humidity storage test, when the state of the vapor deposition film layer at the time of peeling is not described (good), it indicates the peel strength when the peeling film peels from the vapor deposition surface or adhesive surface, etc. It was. In this case, the adhesive surface with the film for peeling peeled off at a value smaller than the peel strength at the interface between the base material to be measured and the deposited film layer (hereinafter referred to as “base material / deposited interface”). Means that.

(Formation of surface modification layer)
The surface of a rigid PVC substrate having a thickness of 100 to 200 μm was surface-modified using an atmospheric pressure plasma processing apparatus. The processing conditions are an irradiation energy of 600 W · min / m ² and a frequency of 5 kHz.
A hard PVC substrate of surface modification example 1 having a surface modification layer on one surface was obtained by atmospheric pressure plasma treatment using nitrogen gas as a reaction gas.
A hard PVC substrate of surface modification example 2 having a surface modification layer on one surface was obtained by atmospheric pressure plasma treatment using carbon dioxide as a reaction gas.
A hard PVC substrate of surface modification example 3 having a surface modification layer on one surface was obtained by atmospheric pressure plasma treatment using oxygen gas as a reaction gas.

(Preparation of rigid PVC substrate on which an Al deposited film layer is formed)
Next, aluminum (Al) was vapor-deposited on the surface on which the surface modification layer of the hard PVC base material of surface modification examples 1 to 3 was formed, to obtain a metal-coated hard PVC base material. In addition, as a control example, aluminum (Al) is vapor-deposited on the surface of a hard PVC base material (untreated) on which no surface modification layer is formed, and a metal-coated hard PVC base material according to the control example is produced. did. For initial adhesion, a cellophane adhesive tape was applied to the Al vapor-deposited surface of a hard-coated PVC substrate, and a cross-cut test was conducted.
Furthermore, a linear low-density polyethylene (L-LDPE) film is bonded on the Al vapor deposition surface via an adhesive, and hard PVC substrate / surface modified layer / Al vapor deposition film layer / adhesive / L-LDPE A test specimen having a configuration was prepared, and a high-temperature and high-humidity storage test (40 ° C. × 90% RH and 60 ° C. × 90% RH) was performed.
The above test results are shown in Tables 1-3.

(Preparation of rigid PVC substrate on which a Cu vapor deposition film layer is formed)
Copper (Cu) was vapor-deposited on the surface on which the surface modification layer of the hard PVC base material of surface modification examples 1 to 3 was formed, to obtain a metal-coated hard PVC base material. As a control example, copper (Cu) is vapor-deposited on the surface of a hard PVC base material (untreated) on which no surface modification layer is formed, thereby producing a metal-coated hard PVC base material according to the control example. did. For initial adhesion, a cellophane adhesive tape was applied to the Cu vapor-deposited surface of the metal-coated hard PVC base material, and a cross-cut test was conducted.
Furthermore, a linear low-density polyethylene (L-LDPE) film is bonded onto the Cu vapor-deposited surface via an adhesive, and hard PVC substrate / surface modified layer / Cu vapor-deposited film layer / adhesive / L-LDPE A test specimen having a configuration was prepared, and a high-temperature and high-humidity storage test (40 ° C. × 90% RH and 60 ° C. × 90% RH) was performed.
The above test results are shown in Tables 4-6.

  In the case of Cu deposition, when surface modification treatment is performed using carbon dioxide gas or oxygen gas as a reaction gas, oxygen atom-containing functional groups (polar functional groups such as COOH) on the substrate surface react with the deposited metal, Discoloration (due to the production of cuprous oxide). When the surface modification treatment was performed using nitrogen gas as a reaction gas, a Cu vapor deposition film layer without discoloration could be formed.

(Preparation of rigid PVC substrate with Ni vapor deposition film layer)
Nickel (Ni) was vapor-deposited on the surface on which the surface modification layer of the hard PVC base material of surface modification examples 1 to 3 was formed to obtain a metal-coated hard PVC base material. Further, as a control example, nickel (Ni) is vapor-deposited on the surface of a hard PVC base material (untreated) on which no surface modification layer is formed, and a metal-coated hard PVC base material according to the control example is produced. did. For initial adhesion, a cellophane adhesive tape was applied to the Ni vapor-deposited surface of a metal-coated hard PVC substrate, and a cross-cut test was conducted.
Furthermore, a linear low-density polyethylene (L-LDPE) film is bonded onto the Ni vapor-deposited surface via an adhesive, and hard PVC substrate / surface modified layer / Ni vapor-deposited film layer / adhesive / L-LDPE A test specimen having a configuration was prepared, and a high-temperature and high-humidity storage test (40 ° C. × 90% RH and 60 ° C. × 90% RH) was performed.
The above test results are shown in Tables 7-9.

(Preparation of rigid PVC base material on which Cr vapor deposition film layer is formed)
Chromium (Cr) was vapor-deposited on the surface on which the surface modification layer of the hard PVC base material of surface modification examples 1 to 3 was formed to obtain a metal-coated hard PVC base material. Further, as a control example, chromium (Cr) is vapor-deposited on the surface of a hard PVC base material (untreated) on which a surface modification layer is not formed, and a metal-coated hard PVC base material according to the control example is manufactured. did. For initial adhesion, a cellophane adhesive tape was applied to the Cr vapor-deposited surface of a metal-coated hard PVC base material and a cross-cut test was conducted.
Further, a linear low density polyethylene (L-LDPE) film is bonded on the Cr vapor deposition surface via an adhesive, and the hard PVC substrate / surface modified layer / Cr vapor deposition film layer / adhesive / L-LDPE A test specimen having a configuration was prepared, and a high-temperature and high-humidity storage test (40 ° C. × 90% RH) was performed.
The above test results are shown in Tables 10-11.

(Summary)
From the above results, it was possible to confirm an improvement in peel strength required for peeling by forming a surface modified layer on the surface of the hard PVC substrate by atmospheric pressure plasma treatment and then depositing a metal. Therefore, it was possible to obtain a metal-coated hard vinyl chloride substrate having excellent adhesion to metal (no partial peeling and adhesion to the entire film).

Claims (5)

  A metal-coated hard, characterized in that a surface modification layer is provided on the surface of a substrate made of hard vinyl chloride, and a metal thin film layer is deposited by vapor deposition through the surface modification layer of the substrate Vinyl chloride base material.   The metal-coated hard vinyl chloride substrate according to claim 1, wherein the surface modification layer contains at least a carboxyl group as a functional group.   The metal-coated hard vinyl chloride substrate according to claim 1 or 2, wherein the surface modification layer is formed by an atmospheric pressure plasma treatment using nitrogen gas as a reaction gas.   The metal thin film layer includes at least one selected from the group consisting of aluminum, copper, nickel, chromium, gold, silver, platinum, tin, zinc, metal oxide, and metal oxide. The metal-coated hard vinyl chloride substrate according to any one of claims 1 to 3.   5. The metal-coated hard vinyl chloride base material according to claim 1, wherein the base material is any one selected from the form of a resin film, a resin sheet, and a resin plate.