JP5183981B2 - Surface modification method and surface coating method for articles made of liquid crystal polymer material - Google Patents

Description

  The present invention relates to a surface modification method for an article made of a liquid crystal polymer material, and a method for coating the surface of an article made of a liquid crystal polymer material surface-modified by the surface modification method with a conductive thin film.

  Since liquid crystal polymer materials are excellent in mechanical properties such as heat resistance and rigidity, chemical resistance and dimensional accuracy, their use is expanding not only for molded products but also for various applications such as fibers and films. Especially in the field of information and communications such as personal computers and mobile phones, high integration of parts, miniaturization, thinning, low profile, etc. are progressing rapidly, and very thin parts with a thickness of 0.5 mm or less. In many cases, the liquid crystal polymer material has excellent moldability, that is, good fluidity and no burrs. ing.

  A liquid crystal polymer film made of such a liquid crystal polymer material is excellent in electrical characteristics (low dielectric constant, low dielectric loss) in a high frequency region (GHz band), and has a low power loss in a circuit. ) It is attracting attention as a material such as a substrate.

  Thus, the liquid crystal polymer material contributes to the miniaturization of many electric and electronic parts. Such an electric / electronic component needs to have a metal film adhered directly to the surface of a film or a molded product in order to impart conductivity to a circuit pattern, an electromagnetic wave shield, or the like. However, the liquid crystal polymer material has low adhesion to a metal thin film, and it has been difficult to ensure sufficient quality as an electric / electronic component.

  Conventionally, in order to improve the adhesion problem between the liquid crystal polymer material and the metal thin film, the surface of the liquid crystal polymer material is roughened by a method such as etching, or various plasma treatments are performed on the surface of the liquid crystal polymer material. Thus, after modifying the surface, a method of forming a metal thin film has been taken (see Patent Documents 1 to 3 and Non-Patent Document 1).

  For example, Patent Document 1 discloses that after the surface of a liquid crystalline polyester is etched, surface metal coating is performed by any of sputtering, ion plating, and vacuum deposition. In this method, the surface of the liquid crystalline polyester is roughened, and an adhesive force is obtained based on the mechanical anchor effect with respect to the unevenness of the rough surface. However, this method has a problem that the surface roughness of the obtained molded body is too high, and it is difficult to make a fine line of a circuit formed on the surface of the molded body.

  Patent Document 2 discloses a method of forming a metal film by any one of sputtering, vacuum deposition, and ion plating after plasma treatment is performed on the surface of a semi-aromatic liquid crystalline polyester molded article. Yes. However, according to this method, although the adhesion strength between the surface of the molded product and the metal film is improved, it cannot be said that the strength is practically sufficient, and there is still room for improvement.

  Further, Patent Document 3 discloses a method of forming a metal seed layer by a sputtering method after performing a discharge plasma treatment on the liquid crystal polymer film surface under an atmosphere of oxygen gas pressure of 0.6 to 2.5 Pa. Non-Patent Document 1 discloses that a liquid crystal polymer film surface and a copper thin film are obtained by treating the liquid crystal polymer film surface with various plasmas and modifying (hydrophilizing) the water contact angle of the film surface to about 38 to 60 °. A method for improving the adhesion strength between the two is disclosed. However, in any of the methods, the adhesion strength between the liquid crystal polymer film and the metal thin film is not practically sufficient.

As described above, a technique for obtaining the surface of an article made of a liquid crystal polymer material having high adhesion to a metal thin film and sufficiently smooth surface to form a precision fine wire circuit has not yet been found. Not.
Japanese Patent Publication No. 7-24328 JP 2003-268089 A JP 2005-297405 A N. Inagaki, Yong Woo Park, Kazuo Narushim, K Miyazaki, J. et al. Adhes. Sci. Technol. , Vol. 18, no. 12, pp 1427-1447 (2004)

  The object of the present invention is to improve the surface of an article made of a liquid crystal polymer material in order to obtain a surface suitable for forming a conductive thin film excellent in adhesion to a conductive thin film such as metal and having excellent surface smoothness. To provide a quality method.

  A further object of the present invention is to provide a surface coating method for an article made of a liquid crystal polymer material for coating the surface of the article made of a surface-modified liquid crystal polymer material with a conductive thin film having excellent adhesion and surface smoothness. It is to provide.

  As a result of intensive studies to achieve the above object, the present inventors have found that the surface of the article made of a liquid crystal polymer material is highly hydrophilicized by ion irradiation. In addition, the inventors have found that a conductor thin film having excellent adhesion and excellent surface smoothness can be formed by forming a conductor thin film on the surface of an article made of a liquid crystal polymer material surface-modified by ion irradiation. It came to be completed.

  That is, the present invention provides a method for modifying the surface of an article made of a liquid crystal polymer material, which comprises irradiating the surface of the article made of a liquid crystal polymer material with ions.

  The present invention also provides a step of modifying the surface of an article made of liquid crystal polymer material by irradiating the surface of the article made of liquid crystal polymer material with ions, and the surface of the article made of surface modified liquid crystal polymer material Forming a conductor thin film on a part or all of the surface of the article.

  In the present specification and claims, a “liquid crystal polymer” is a polyester or polyester amide that forms an anisotropic melt phase, and what is known to those skilled in the art as a thermotropic liquid crystal polyester or a thermotropic liquid crystal polyester amide. There is no particular limitation.

  The property of the anisotropic molten phase can be confirmed by a normal deflection inspection method using an orthogonal deflector, that is, by observing a sample placed on a hot stage in a nitrogen atmosphere.

  In the present specification and claims, the “liquid crystal polymer material” is not only a material composed of only the liquid crystal polymer (hereinafter also referred to simply as “liquid crystal polymer”), but also the liquid crystal polymer described later. It is meant to include a composition containing a liquid crystal polymer (hereinafter also simply referred to as “liquid crystal polymer composition”) obtained by optionally blending additives, other resin components other than the liquid crystal polymer, and a filler.

  In the case where the liquid crystal polymer material contains at least one of additives, other resin components, and fillers in addition to the liquid crystal polymer, the content of the substance other than the liquid crystal polymer is 200 with respect to 100 parts by weight of the liquid crystal polymer. Up to parts by weight are preferred, up to 150 parts by weight are better, and up to 100 parts by weight are best.

  Hereinafter, the liquid crystal polymer material used in the method of the present invention will be described.

  As the repeating unit constituting the liquid crystal polymer used in the present invention, aromatic oxycarbonyl repeating unit, aromatic dicarbonyl repeating unit, aromatic dioxy repeating unit, aromatic aminooxy repeating unit, aromatic aminocarbonyl repeating unit, aromatic Examples thereof include a diamino repeating unit, an aromatic oxydicarbonyl repeating unit, and an aliphatic dioxy repeating unit.

  The liquid crystal polymer composed of each of these repeating units may or may not form an anisotropic molten phase depending on the constituent components, the composition ratio in the polymer, and the sequence distribution, but the liquid crystal used in the present invention. Polymers are limited to those that form an anisotropic melt phase.

  Specific examples of the monomer that gives an aromatic oxycarbonyl repeating unit include, for example, parahydroxybenzoic acid, metahydroxybenzoic acid, orthohydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, and 5-hydroxy-2-naphthoic acid. 3-hydroxy-2-naphthoic acid, 4'-hydroxybiphenyl-4-carboxylic acid, 3'-hydroxybiphenyl-4-carboxylic acid, 4'-hydroxybiphenyl-3-carboxylic acid, their alkyl, alkoxy or halogen Substituents and ester-forming derivatives thereof such as acylated products, ester derivatives, acid halides and the like can be mentioned. Among these, parahydroxybenzoic acid and 6-hydroxy-2-naphthoic acid are preferable from the viewpoint of easy adjustment of characteristics and melting point of the liquid crystal polymer.

  Specific examples of the monomer giving the aromatic dicarbonyl repeating unit include terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1, Examples thereof include aromatic dicarboxylic acids such as 4-naphthalenedicarboxylic acid and 4,4′-dicarboxybiphenyl, alkyl, alkoxy or halogen-substituted products thereof, and ester-forming derivatives such as ester derivatives and acid halides thereof. Among these, terephthalic acid and 2,6-naphthalenedicarboxylic acid are preferable because the liquid crystal polymer from which terephthalic acid and 2,6-naphthalenedicarboxylic acid are obtained can easily adjust the mechanical properties, heat resistance, melting point temperature, and moldability to appropriate levels.

  Specific examples of the monomer giving an aromatic dioxy repeating unit include, for example, hydroquinone, resorcin, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 4 Aromatic diols such as 4,4'-dihydroxybiphenyl, 3,3'-dihydroxybiphenyl, 3,4'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl ether, alkyl, alkoxy or halogen substituents thereof, and Examples thereof include ester-forming derivatives such as acylated products. Among these, hydroquinone and 4,4'-dihydroxybiphenyl are preferable from the viewpoint of reactivity during polymerization, characteristics of the obtained liquid crystal polymer, and the like.

  Specific examples of the monomer that gives an aromatic aminooxy repeating unit include, for example, p-aminophenol, m-aminophenol, 4-amino-1-naphthol, 5-amino-1-naphthol, and 8-amino-2- Aromatic hydroxyamines such as naphthol and 4-amino-4′-hydroxybiphenyl, alkyl, alkoxy or halogen substituents thereof, and ester or amide-forming derivatives thereof such as acylated products thereof can be mentioned.

  Specific examples of the monomer that gives an aromatic aminocarbonyl repeating unit include aromatic aminocarboxylic acids such as p-aminobenzoic acid, m-aminobenzoic acid, and 6-amino-2-naphthoic acid, their alkyls, Examples thereof include alkoxy or halogen-substituted products, and ester or amide-forming derivatives thereof such as acylated products, ester derivatives, and acid halides.

  Specific examples of the monomer that gives an aromatic diamino repeating unit include aromatic diamines such as p-phenylenediamine, m-phenylenediamine, 1,5-diaminonaphthalene, 1,8-diaminonaphthalene, alkyls thereof, Examples include amide-forming derivatives such as alkoxy or halogen-substituted products, and acylated products thereof.

  Specific examples of monomers that give aromatic oxydicarbonyl repeating units include hydroxyaromatic dicarboxylic acids such as 3-hydroxy-2,7-naphthalenedicarboxylic acid, 4-hydroxyisophthalic acid, and 5-hydroxyisophthalic acid. And alkyl-substituted, alkoxy- or halogen-substituted products thereof, and ester-forming derivatives such as acylated products, ester derivatives, and acid halides thereof.

  Specific examples of the monomer giving the aliphatic dioxy repeating unit include aliphatic diols such as ethylene glycol, 1,4-butanediol, 1,6-hexanediol, and acylated products thereof. In addition, polyesters containing aliphatic dioxy repeating units such as polyethylene terephthalate and polybutylene terephthalate are mixed with the above aromatic oxycarboxylic acid, aromatic dicarboxylic acid, aromatic diol, aromatic hydroxyamine, aromatic aminocarboxylic acid, A liquid crystal polymer containing an aliphatic dioxy repeating unit can also be obtained by reacting with an aromatic diamine, a hydroxyaromatic dicarboxylic acid and an acylated product, an ester derivative, an acid halide, or the like thereof.

  The liquid crystal polymer used in the present invention may contain a thioester bond as long as the object of the present invention is not impaired. Examples of the monomer that gives such a bond include mercapto aromatic carboxylic acid, aromatic dithiol, and hydroxy aromatic thiol. These monomers are used in an aromatic oxycarbonyl repeating unit, an aromatic dicarbonyl repeating unit, an aromatic dioxy repeating unit, an aromatic aminooxy repeating unit, an aromatic aminocarbonyl repeating unit, an aromatic diamino repeating unit, The amount is preferably 10 mol% or less based on the total amount of monomers giving the aromatic oxydicarbonyl repeating unit and the aliphatic dioxy repeating unit.

  As mentioned above, although the repeating unit contained in the liquid crystal polymer used in this invention and the monomer which gives it were demonstrated, the liquid crystal polymer used in this invention is an aromatic oxycarbonyl repeating unit, 4-oxybenzoyl repeating unit, and / or Or it is more preferable to use what contains a 6-oxy-2- naphthoyl repeating unit.

  Among the liquid crystal polymers containing 4-oxybenzoyl repeating units and / or 6-oxy-2-naphthoyl repeating units, preferred are, for example, copolymers obtained from the following monomer constituent units.

1) 4-hydroxybenzoic acid / 2-hydroxy-6-naphthoic acid copolymer 2) 4-hydroxybenzoic acid / terephthalic acid / 4,4'-dihydroxybiphenyl copolymer 3) 4-hydroxybenzoic acid / terephthalic acid / Isophthalic acid / 4,4'-dihydroxybiphenyl copolymer 4) 4-hydroxybenzoic acid / terephthalic acid / isophthalic acid / 4,4'-dihydroxybiphenyl / hydroquinone copolymer 5) 4-hydroxybenzoic acid / terephthalic acid / Hydroquinone copolymer 6) 2-hydroxy-6-naphthoic acid / terephthalic acid / hydroquinone copolymer 7) 4-hydroxybenzoic acid / 2-hydroxy-6-naphthoic acid / terephthalic acid / 4,4'-dihydroxybiphenyl Copolymer 8) 2-hydroxy-6-naphthoic acid / terephthalic acid / 4,4'-dihydroxybi Phenyl copolymer 9) 4-hydroxybenzoic acid / 2-hydroxy-6-naphthoic acid / terephthalic acid / hydroquinone copolymer 10) 4-hydroxybenzoic acid / 2,6-naphthalenedicarboxylic acid / 4,4'-dihydroxy Biphenyl copolymer 11) 4-hydroxybenzoic acid / terephthalic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone copolymer 12) 4-hydroxybenzoic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone copolymer 13) 4 -Hydroxybenzoic acid / 2-hydroxy-6-naphthoic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone copolymer 14) 4-hydroxybenzoic acid / terephthalic acid / 2,6-naphthalenedicarboxylic acid / hydroquinone / 4,4 '-Dihydroxybiphenyl copolymer 15) 4-hydroxybenzoic acid / tere Taric acid / 4-aminophenol copolymer 16) 2-hydroxy-6-naphthoic acid / terephthalic acid / 4-aminophenol copolymer 17) 4-hydroxybenzoic acid / 2-hydroxy-6-naphthoic acid / terephthalic acid / 4-aminophenol copolymer 18) 4-hydroxybenzoic acid / terephthalic acid / 4,4'-dihydroxybiphenyl / 4-aminophenol copolymer 19) 4-hydroxybenzoic acid / terephthalic acid / ethylene glycol copolymer 20) 4-hydroxybenzoic acid / terephthalic acid / 4,4′-dihydroxybiphenyl / ethylene glycol copolymer 21) 4-hydroxybenzoic acid / 2-hydroxy-6-naphthoic acid / terephthalic acid / ethylene glycol copolymer 22 ) 4-hydroxybenzoic acid / 2-hydroxy-6-naphthoic acid / teref Taric acid / 4,4′-dihydroxybiphenyl / ethylene glycol copolymer.

Hereinafter, in the present invention, a liquid crystal polymer material used as a molding material for various articles to be irradiated with ions, that is, a liquid crystal polymer and a method for producing a liquid crystal polymer composition in which other components are added to the liquid crystal polymer will be described. .
First, a method for producing a liquid crystal polymer that is an essential component of the liquid crystal polymer material used in the present invention will be described.

  The production method of the liquid crystal polymer used in the present invention is not particularly limited, and a known polycondensation method for forming an ester bond or an amide bond composed of a combination of the above monomers, for example, a melt acidosis method, a slurry polymerization method, or the like is used. Can do.

  The melt acidosis method is a preferred method for use in the method for producing a liquid crystal polymer used in the present invention, and this method first heats a monomer to form a molten liquid of a reactant, and then performs a reaction. Subsequently, a molten polymer is obtained. Note that a vacuum may be applied to facilitate removal of volatiles (for example, acetic acid, water, etc.) by-produced in the final stage of the condensation.

  The slurry polymerization method is a method of reacting in the presence of a heat exchange fluid, and the solid product is obtained in a state suspended in a heat exchange medium.

  In any case of the melt acidification method and the slurry polymerization method, the polymerizable monomer component used in producing the liquid crystal polymer is a modified form in which hydroxyl groups and / or amino groups are acylated at room temperature, that is, lower It can also be subjected to the reaction as an acylated product. The lower acyl group preferably has 2 to 5 carbon atoms, more preferably 2 or 3 carbon atoms. Particularly preferred is a method using an acetylated product of the monomer in the reaction.

  The acylated product of the monomer may be prepared by separately acylating and synthesized in advance, or it may be generated in the reaction system by adding an acylating agent such as acetic anhydride to the monomer during the production of the liquid crystal polymer. it can.

  In any case of the melt acidification method or the slurry polymerization method, a catalyst may be used as needed during the reaction.

  Specific examples of the catalyst include organotin compounds such as dialkyltin oxide (for example, dibutyltin oxide) and diaryltin oxide; antimony trioxide; titanium dioxide; organotitanium compounds such as alkoxytitanium silicate and titanium alkoxide; alkali or alkali of carboxylic acid Examples include earth metal salts (for example, potassium acetate); inorganic acid salts (for example, potassium sulfate); Lewis acid (for example, boron trifluoride); gaseous acid catalysts such as hydrogen halide (for example, hydrogen chloride).

  The use ratio of the catalyst is usually 10 to 1000 ppm, preferably 20 to 200 ppm, based on the monomer.

  The liquid crystal polymers obtained by the polycondensation reaction in this manner are each extracted from the polymerization reaction tank in a molten state, and then processed into pellets, flakes, or powders.

  The obtained liquid crystal polymer in the form of pellets, flakes, or powders is subjected to heat treatment in a substantially solid state under reduced pressure or in an inert gas atmosphere for the purpose of increasing molecular weight and improving heat resistance. May be.

  Although the processing temperature in the case of performing the heat processing performed in a solid state is not particularly limited as long as the liquid crystal polymer is not melted, it is preferably 260 to 350 ° C, preferably 280 to 320 ° C.

In addition, as a liquid crystal polymer used for this invention, the thing whose crystal melting temperature (Tm) measured with the differential scanning calorimeter is 280 degreeC-360 degreeC is preferable.
[Method for measuring crystal melting temperature]
Exstar 600 manufactured by Seiko Instruments Inc. is used as a differential scanning calorimeter.
The sample is held for 10 minutes at a temperature 20 to 50 ° C. higher than Tm1, which is a measurement word of an endothermic peak temperature (Tm1) observed when the temperature is measured at room temperature from a temperature of 20 ° C./min. Next, the sample was cooled to room temperature under a temperature drop condition of 20 ° C./min, and an endothermic peak was measured again when measured under a temperature rise condition of 20 ° C./min. The temperature showing the peak top was determined as the crystal melting temperature ( Tm).

  The liquid crystal polymer thus obtained is used as it is or after it is made into a liquid crystal polymer composition containing at least one component selected from the group consisting of various additives, other resin components, and fillers. It is used as a molding material for various articles.

  Next, a liquid crystal polymer composition in which one or more components selected from the group consisting of various additives, other resin components, and fillers are blended with the liquid crystal polymer will be described.

  In addition to the liquid crystal polymer used in the present invention, a mold release improver such as a higher fatty acid, a higher fatty acid ester, a higher fatty acid amide, a higher fatty acid metal salt, a polysiloxane, and a fluororesin, as long as the object of the present invention is not impaired; One or more additives selected from colorants such as pigments, antioxidants, heat stabilizers, ultraviolet absorbers, antistatic agents, and surfactants may be added in combination.

Those having an external lubricant effect such as higher fatty acid, higher fatty acid ester, higher fatty acid metal salt, and fluorocarbon surfactant may be previously adhered to the surface of liquid crystal polymer pellets during molding.
Here, the higher fatty acid means one having 10 to 25 carbon atoms.

  The amount of these additives is preferably 0.05 to 1 part by weight, particularly preferably 0.1 to 0.5 part by weight, based on 100 parts by weight of the liquid crystal polymer.

  In addition, other resin components such as polyamide, polyester, polyphenylene sulfide, polyetherketone, polycarbonate, polyphenylene ether, and modified products thereof, polysulfone are used as long as the object of the present invention is not impaired with respect to the liquid crystal polymer used in the present invention. One or more selected from thermoplastic resins such as polyethersulfone and polyetherimide, and thermosetting resins such as phenol resin, epoxy resin, and polyimide resin may be added in combination.

  The compounding amount of the other resin component of these liquid crystal polymers is preferably used up to 200 parts by weight, particularly preferably up to 100 parts by weight, with respect to 100 parts by weight of the liquid crystal polymer.

  As the liquid crystal polymer material used in the present invention, it is preferable to use a liquid crystal polymer in which a filler is blended. The form of the filler to be blended with the liquid crystal polymer is not particularly limited as long as the object of the present invention is not impaired, but one or more fillers selected from fibrous, plate-like and powdery fillers are used. Is preferred.

  Examples of the fibrous filler include glass fiber, milled glass, silica alumina fiber, alumina fiber, carbon fiber, aramid fiber, potassium titanate whisker, aluminum borate whisker, and wollastonite. In these, glass fiber is preferable at the point which the balance of a physical property and cost is excellent. Examples of the plate-like or powdery filler include talc, mica, graphite, calcium carbonate, dolomite, clay, glass flakes, glass beads, barium sulfate, and titanium oxide.

  In the present invention, the blending amount of the filler is usually preferably 0 to 200 parts by weight and more preferably 20 to 100 parts by weight with respect to 100 parts by weight of the liquid crystal polymer.

  When the blending amount of the filler exceeds 200 parts by weight, molding processability tends to be reduced, and wear of the cylinder and mold of the molding machine tends to increase.

  In the present invention, the shape of an article made of a liquid crystal polymer material to be subjected to ion irradiation is not particularly limited. In addition, the article to be subjected to ion irradiation may be a composite article with an article made of glass, ceramic, or other resin material as long as an article made of a liquid crystal polymer material is included.

  In the present invention, a film or a sheet is particularly preferable among the shapes of articles to be irradiated with ions. The film or sheet made of the liquid crystal polymer material used in the present invention can be produced by an extrusion method, a T-die method, a laminate stretching method, an inflation method and the like well known to those skilled in the art.

  Among these film or sheet production methods, the difference in the thermal expansion coefficient between the longitudinal direction and the transverse direction of the obtained film or sheet is small, and the balance between mechanical properties and thermal properties is excellent. A laminate stretching method is more preferable.

  In the present invention, when a film or sheet made of a liquid crystal polymer material is used as an object to be irradiated with ions, the film or sheet may have any thickness, but is preferably 20 μm to 1 mm in thickness. The thing of 20-150 micrometers is especially preferable, and the thing of thickness 20-50 micrometers is the most preferable.

  When a film or sheet made of a liquid crystal polymer material is thinner than 20 μm, the film or sheet becomes less rigid and strong, so when mounting electronic parts on a wiring board made of the liquid crystal polymer material obtained, the film Or a sheet | seat deform | transforms by pressurization, the positional accuracy of wiring deteriorates, and it becomes easy to produce a defective product.

  The film or sheet made of a liquid crystal polymer material used in the present invention may be a laminate of a film or sheet made of a liquid crystal polymer material. If at least one of the outer layers is a film or sheet made of a liquid crystal polymer material, a metal It may be a laminated film or laminated sheet with a film or sheet using a foil or other resin material.

  Next, ion irradiation on the surface of an article made of a liquid crystal polymer material in the present invention will be described.

  In the present specification and claims, “ion irradiation” refers to extraction and extraction of ions from plasma generated by various plasma generators (for example, ECR devices) by applying an acceleration voltage with an ion extraction electrode. Means to irradiate an article made of a liquid crystal polymer material.

  Preferably, the ion irradiation in the method of the present invention is positive ion irradiation.

  Any conventionally known method may be used for ion irradiation. For example, ion irradiation is performed by using an ion irradiation apparatus provided with an ion extraction electrode in a plasma generator, such as a bipolar discharge type, a thermionic discharge type, a magnetic field focusing type (magnetron discharge type), or an electrodeless discharge type. I can do it. Among these, it is preferable to use an ECR (electron cyclotron resonance) type plasma apparatus that also has an ion extraction electrode.

  An ECR type plasma apparatus is an apparatus that accelerates electrons resonantly by the interaction between an electric field and a magnetic field, and gas is turned into plasma by collision of the electrons, and plasma composed of high-density ions, radicals, electrons, etc. can get. Preferable examples of the gas to be converted into plasma include argon, oxygen, nitrogen, hydrogen, water vapor, and ammonia. Among these gases, it is more preferable to use argon and / or water vapor because the surface modification effect is high. These gases may be used as a mixed gas.

In the present invention, performing ion irradiation with an ECR type plasma apparatus refers to irradiating a sample in a vacuum chamber with cations out of plasmaized gas with an ion gun.
Further, the acceleration voltage in ion irradiation may be appropriately selected in the range of 50 to 1000 V in consideration of the damage on the sample surface, the modification effect, and the like.

  By the method of the present invention, the surface of an article made of a liquid crystal polymer material can be highly hydrophilized. By this treatment, the surface of the article made of the liquid crystal polymer material preferably exhibits a water contact angle of 35 degrees or less, more preferably 30 degrees or less. Here, the water contact angle of the modified surface referred to here is a value obtained by measurement immediately after ion irradiation.

  The present invention provides an article comprising a surface modified liquid crystal polymer material obtained by the method of the present invention. An article made of a liquid crystal polymer material that has been surface-modified by ion irradiation according to the method of the present invention has a highly hydrophilic surface, and preferably exhibits a very low water contact angle of 35 degrees or less.

  When a conductor thin film is formed on the surface of an article made of a liquid crystal polymer material whose surface has been modified in this way, an article made of a liquid crystal polymer material coated with a conductor thin film having excellent adhesion to the surface of the liquid crystal polymer material. can get.

  Hereinafter, a method for forming a conductive thin film on the surface of an article made of a liquid crystal polymer material whose surface has been modified by the method of the present invention will be described.

  In the present invention, the conductor thin film formed on the surface of the article made of the surface-modified liquid crystal polymer material may cover the whole surface of the article made of the liquid crystal polymer material, or partially covers it. It may be a thing.

  Examples of the conductor used for forming the conductor thin film in the present invention include simple metals selected from copper, nickel, gold, aluminum, titanium, molybdenum, chromium, tungsten, lead, zinc, and tin, and alloys thereof. Examples thereof include metals and inorganic conductors such as indium tin oxide. Preferably, the conductor is a simple substance of copper.

  In the present invention, the method for forming a conductor thin film on part or all of the surface of an article made of a surface-modified liquid crystal polymer material using the above-described conductor is not particularly limited, and various known methods may be used. I can do it. Suitable methods for forming the conductive thin film include, for example, sputtering, vacuum deposition, ion plating, electroless plating, and electrolytic plating. Among these conductor thin film forming methods, it is more preferable to use sputtering.

  Hereinafter, sputtering will be described. In the present invention, as a method for performing sputtering, for example, an ECR sputtering method can be applied.

  Specifically, first, after setting a sample in the chamber, the pressure in the chamber is reduced by a vacuum pump, and in this state, an inert gas such as argon is introduced into the chamber so as to have a predetermined gas pressure. . Furthermore, by applying a predetermined voltage, a conductive material target such as copper can be bombarded to form a conductive thin film (such as a copper thin film) on the sample surface.

  When forming a conductive thin film by sputtering, the thickness of the thin film is preferably from 0.1 to 1.0 μm, and more preferably from 0.2 to 0.5 μm.

Next, a method for forming a conductive thin film other than sputtering will be briefly described.
Vacuum deposition is a method in which a conductive material is heated to a high temperature in a chamber under high vacuum to evaporate, and a conductive thin film layer is formed on the surface of the insulating substrate.
Ion plating uses the insulating substrate as the cathode and the conductor material evaporation source as the anode, ionizes the evaporated atoms of the conductor material by causing a discharge in a vacuum or gas atmosphere, and forms a conductor thin film layer on the insulating substrate. It is a method of forming.
Electroless plating is a method of forming a conductor thin film layer by depositing a conductor having a uniform thickness on an insulating substrate by chemical reduction.
Electroplating is a method in which a sample of a conductive material such as a metal is electrolyzed in a suitable electrolyte solution to form a metal layer that is thinly adhered on the sample surface.

  In addition, when a conductor thin film is formed as a precise fine wire circuit pattern on the surface of an article made of a surface-modified liquid crystal polymer material, conventionally known additive methods, semi-additive methods, subtractive methods described below Etc. may be used.

The additive method is a method of forming a conductive thin film layer only on a wiring pattern portion on an insulating substrate.
In the semi-additive method, after forming a plating resist pattern on the conductive thin film layer formed on the insulating substrate, forming the conductive layer on the conductive thin film layer exposed by plating, and further removing the plating resist pattern Etching is performed to remove a portion of the conductive thin film layer covered with the plating resist pattern, thereby forming a wiring pattern.
In the subtractive method, a resist layer is formed on a conductor layer formed on an insulating substrate, patterned by photolithography, and then the conductor layer is patterned by etching.

  According to the method of the present invention, a conductor thin film having excellent adhesion and excellent surface smoothness can be formed on the surface of various articles made of a liquid crystal polymer material. Further, after the thin film is formed, the thickness of the conductive thin film can be increased by a normal wet plating method or the like.

  Since an article made of a liquid crystal polymer material whose surface has been modified by the method of the present invention has a smooth surface, a conductive thin film as a precise fine wire circuit pattern can be easily formed thereon. An article made of a liquid crystal polymer material whose surface is coated with a conductive thin film by the method of the present invention can be suitably used as a high-frequency circuit.

  An article made of a liquid crystal polymer material whose surface is coated with a conductive thin film obtained by the present invention is useful as, for example, a MID (Molded Interconnect Device) for forming a metal film circuit directly on a molded article. In addition, when the article made of the liquid crystal polymer material covered with the conductive thin film is a film or a sheet, an electronic component such as a printed wiring board, a flexible printed circuit board, a TAB (Tape Automated Bonding) tape, a COF (Chip on Film) tape, etc. It is useful as a material.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to a following example at all.

Examples 1-2 and Reference Examples 1-2
[Specimen creation]
A liquid crystal polymer (UENO-LCP 6040GM, manufactured by Ueno Pharmaceutical Co., Ltd.) was injection molded using a mirror-finished mold to prepare a 55 × 90 × 0.8 mm test piece.

[Ion irradiation]
The test piece was washed with acetone and degreased, and then set in the chamber of the ECR apparatus, and the chamber was evacuated. Under the conditions shown in Table 1, plasma of argon gas or water vapor was generated by an ECR apparatus, and each cation was irradiated on the surface of the test piece.

  After ion irradiation, the inside of the chamber was returned to atmospheric pressure, and the water contact angle of the test piece was immediately measured with a contact angle meter (CA-D9, manufactured by Kyowa Science Co., Ltd.). The surface roughness (Ra) was measured with a surface roughness meter (manufactured by Tokyo Seimitsu Co., Ltd., Surfcom 130A) according to JIS B0601.

(Copper film formation)
The copper film was formed by a sputtering method. In copper sputtering, plasma is generated by an ECR apparatus, a copper target material under vacuum is irradiated with ions, copper is repelled from the target material by ion collision, and a copper thin film is formed on the test piece by the repelled copper. The thickness of the copper thin film was set to 0.3 μm. In forming the copper film, copper sputtering was continuously performed without returning to atmospheric pressure after ion irradiation to the test piece.

[Measurement of peel strength of copper film]
On the copper thin film formed on the test piece, a 1 cm wide × 5 cm long film was attached with a modified silicone resin adhesive. After the adhesive was completely cured, the strip-shaped film was peeled off in the 90-degree direction, and the load required at that time was measured. The results are shown in Table 1.

Example 3 and Reference Example 3
Except for using a liquid crystal polymer film (Kuraray Co., Ltd., Bexter OC-X100), experiments and evaluations were performed under the ion irradiation conditions in Table 1 in the same manner as in Examples 1-2 and Reference Examples 1-2 . . The results are shown in Table 1.

Comparative Examples 1 and 2
Except not performing ion irradiation, it experimented and evaluated by the same method as Examples 1-3 and Reference Examples 1-3 . The results are shown in Table 1.

Comparative Example 3
Experiments and evaluations were performed in the same manner as in Examples 1 to 3 and Reference Examples 1 to 3 , except that atmospheric pressure oxygen plasma treatment was performed instead of ion irradiation.

  In the atmospheric pressure oxygen plasma treatment, the atmospheric pressure oxygen plasma treatment of the test piece was performed at the conveyance speed shown in Table 2 using an atmospheric pressure plasma apparatus (manufactured by Matsushita Electric Works Co., Ltd.). The results are shown in Table 2.

注）ＬＣＰ１：上野製薬製 ６０４０ＧＭ：成形品
ＬＣＰ２：クラレ製 ベクスターＯＣ−Ｘ１００：フィルム

Note) LCP1: Ueno Pharmaceutical 6040GM: Molded product LCP2: Kuraray Bexter OC-X100: Film

  As is apparent from Table 1, according to the method of the present invention, the water contact angle of the liquid crystal polymer material is drastically decreased to 30 degrees or less by ion irradiation, and it can be seen that the surface is surprisingly hydrophilic. Moreover, it turns out that the adhesiveness with a metal is several times superior compared with a comparative example. It can also be seen that the surface roughness does not increase so much by ion irradiation.

  In Comparative Example 3, the water contact angle is reduced by the atmospheric pressure oxygen plasma treatment, and the copper film peeling strength is certainly increased as compared with the untreated product (Comparative Example 1). The peel strength has not reached a practical level (about 600 g / cm).

Claims (17)

Comprising steam to a surface of an article made of liquid crystal polymer material is irradiated with ions by ionization, surface modification method of an article made of liquid crystal polymer material. Water contact angle on the surface of the article after the ion irradiation is not more than 35 degrees, the surface modification method according to claim 1. The surface modification method according to claim 1 or 2 , wherein the water contact angle on the surface of the article after ion irradiation is 25 degrees or less.   The surface modification method according to claim 1, wherein the ions are ions irradiated by an ECR type plasma apparatus.   The surface modification method according to claim 1, wherein the shape of the article made of the liquid crystal polymer material is a film or a sheet.   An article comprising a surface-modified liquid crystal polymer material obtained by the surface modification method according to any one of claims 1 to 5.   The article of surface modified liquid crystal polymer material according to claim 6, wherein the liquid crystal polymer comprises 4-oxybenzoyl repeat units and / or 6-oxy-2-naphthoyl repeat units.   The article comprising the surface-modified liquid crystal polymer material according to claim 6 or 7, wherein the liquid crystal polymer material includes one or more fillers selected from fibrous, plate-like, and powdery fillers.   One or more fibrous materials selected from the group consisting of glass fiber, milled glass, silica alumina fiber, alumina fiber, carbon fiber, aramid fiber, potassium titanate whisker, aluminum borate whisker, and wollastonite. And one or more plate-like or powdery fillers selected from the group consisting of talc, mica, graphite, calcium carbonate, dolomite, clay, glass flakes, glass beads, barium sulfate, and titanium oxide 9. An article comprising a surface modified liquid crystal polymer material according to claim 8 selected from the group consisting of:   The article of surface modified liquid crystal polymer material according to claim 9, wherein the filler is glass fiber. Modifying the surface of an article made of a liquid crystal polymer material by the method of any one of claims 1 to 5, and
Forming a conductive thin film on part or all of the surface of an article comprising a surface-modified liquid crystal polymer material;
A method for covering a surface of an article made of a liquid crystal polymer material.   The surface coating method according to claim 11, wherein the step of forming the conductive thin film is performed by a method selected from the group consisting of sputtering, vacuum deposition, ion plating, electroless plating, and electrolytic plating.   The surface coating method according to claim 12, wherein the step of forming the conductive thin film is performed by sputtering.   The conductor is selected from the group consisting of a single metal selected from copper, nickel, gold, aluminum, titanium, molybdenum, chromium, tungsten, lead, zinc, and tin, and an alloy thereof. The surface coating method according to any one of the above.   The surface coating method according to claim 14, wherein the conductor is a simple substance of copper.   An article made of a liquid crystal polymer material coated with a conductive thin film, obtained by the surface coating method according to claim 11.   MID, a printed wiring board, a flexible printed circuit board, a TAB tape, or a COF tape obtained by the surface coating method according to any one of claims 11 to 15.