JP2008088560A - Method for modifying surface of plastic member, method for forming metal film, and method for producing plastic member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface modification method for modifying the surface of the plastic member, which uses the pressurized fluid and which makes it possible to form a metal film having a satisfactory surface roughness and having a high adhesion force. <P>SOLUTION: A surface modification method is provided, which includes permeating a permeative substance into a surface of a plastic member by using a pressurized fluid, and dissolving the permeative substance with a solvent to remove the permeative substance from the surface of the plastic member. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for modifying a surface of a plastic member using a pressurized fluid, a method for forming a metal film, and a method for manufacturing a plastic member.

  As a means for forming a metal conductive film on the surface of a component such as an electronic device made of a plastic molded product, an electroless plating method is currently widely used. The process from the molding of the plastic molded product to the electroless plating is somewhat different depending on the material of the molded product, etc., but in general, resin molding, degreasing of the molded product, etching, neutralization and wetting, catalyst application, catalyst activation, and The electroless plating process is performed in this order.

  In the etching in the conventional electroless plating process, the surface of the plastic molded article is physically roughened using a chromic acid solution or an alkali metal hydroxide solution, and the molded article is formed by an anchor effect on the roughened plastic surface. Adhesion with the plating film is secured. However, these etching solutions require post-treatment such as neutralization, which is a factor of high cost. Moreover, since it is a highly toxic etching solution, there is a problem that its handling is complicated.

  In addition, as a method of forming a metal film on the surface of a plastic member other than the electroless plating method, conventionally, a plastic member (polymer member) using carbon dioxide in a supercritical state (hereinafter also referred to as supercritical carbon dioxide) is used. An electroless plating method has been proposed (see, for example, Non-Patent Document 1). According to the method described in Non-Patent Document 1, an organometallic complex is injected into the surface of a plastic member by dissolving the organometallic complex in supercritical carbon dioxide and bringing the supercritical carbon dioxide into contact with various polymer members. (Infiltrate). Next, the fine metal particles are deposited on the surface of the polymer member by reducing the organometallic complex by, for example, heating or chemical reduction treatment on the polymer member infiltrated with the organometallic complex. Thereby, the entire surface of the polymer member can be electrolessly plated. According to this process, it is said that it is possible to realize an electroless plating process of a resin that does not require waste liquid treatment and has a good surface roughness.

  In addition, a plating pretreatment process using a photocatalyst has been proposed as a process for suppressing surface roughening of a plastic member and obtaining a good anchor effect (see, for example, Patent Document 1). In Patent Document 1, titanium oxide is used as a photocatalyst, which is applied to the surface of a plastic member and irradiated with ultraviolet rays to form fine irregularities on the surface of the plastic member. Next, a plating film is formed on the formed uneven surface.

  Conventionally, a method of making a resin composition porous using supercritical carbon dioxide has been proposed (see, for example, Patent Document 2). In Patent Document 2, a porous polyamic acid resin is formed by removing a dispersible compound from a photosensitive resin composition containing a polyamic acid resin which is a polyimide precursor and a dispersible compound dispersible therein. To do. In Patent Document 2, a conductive layer is formed on a porous polyamic acid resin. However, in Patent Document 2, the resin material is limited to polyimide resin, and the physical shape on the outermost surface of the resin is not disclosed, and there is no description regarding the adhesion between the resin and the conductive layer.

JP-A-2005-85900 JP 2001-215701 A Teruo Hori, “Latest Application Technology of Supercritical Fluids”, NTS Publishing, p. 250-255 (2004)

  As a result of intensive studies by the inventors on the surface modification process using supercritical carbon dioxide described in Non-Patent Document 1, it has been found that there are the following problems. In the surface modification process using supercritical carbon dioxide, since the surface of the plastic member is not physically roughened, the surface smoothness is good, but the anchor is at the interface between the plating film and the plastic member. The effect is not obtained. When a plating film is formed on the surface of a plastic member by the method of Non-Patent Document 1, adhesion of the plating film is ensured by the permeated organometallic complex. Therefore, the adhesion of the plating film is affected by the reducing property of the organometallic complex and the density and aggregation state of the metal fine particles on the surface of the plastic member resulting therefrom. It turns out that it is difficult to control all these conditions.

  When the photocatalytic process using titanium oxide described in Patent Document 2 is used to roughen the surface of the plastic member, the surface of the plastic member is irradiated with ultraviolet rays to generate a photocatalytic reaction. Since it is necessary, it is considered to be applicable to a molded article having a two-dimensional shape (for example, a film), but the surface of a complicated three-dimensional shaped article is uniformly irradiated with ultraviolet rays. Is considered difficult. In addition, since the reaction time of the photocatalyst is as long as several tens of minutes, the length of the reaction time may become a problem in industrialization.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a method for modifying the surface of a plastic member capable of forming a metal film having good surface roughness and high adhesion. Another object is to provide a method for forming a metal film and a method for producing a plastic member.

  As described above, an electroless plating method is conventionally known as a method for forming a metal film at a low cost on the surface of a plastic member (polymer member). However, in this method, the surface of the polymer member needs to be roughened by etching with chromic acid or the like, and the polymer roughened with these etching solutions is limited to a resin such as ABS. In addition, for other materials such as polycarbonate which are not easily roughened by the etching solution, a plating grade resin material mixed with ABS or elastomer is commercially available in order to enable electroless plating. However, such a plating grade resin material does not sufficiently satisfy the requirements for heat resistance and reflection performance.

  Accordingly, another object of the present invention is to provide a plastic member surface modification method and metal film formation capable of forming a plating film having good surface roughness and high adhesion to various types of plastics. Is to provide a method. Still another object of the present invention is to provide a plastic member having fine irregularities on the surface and good surface roughness for various types of plastics.

  According to the first aspect of the present invention, there is provided a method for modifying a surface of a plastic member, wherein a penetrating substance is infiltrated into the surface of the plastic member using a pressurized fluid, and a solvent is brought into contact with the plastic member. There is provided a surface modification method comprising dissolving the osmotic substance in the solvent and removing the osmotic substance from the surface of the plastic member.

  In the surface modification method of the present invention, first, a penetrating substance is permeated into the surface of the plastic member using a pressurized fluid (step S1 in FIG. 22). For example, the surface of the plastic member is swollen by bringing a pressurized fluid in which the osmotic material is dissolved into contact with the surface of the plastic member, and the osmotic material is infiltrated into the surface of the plastic member together with the pressurized fluid. Then, the osmotic substance is removed from the surface of the plastic member by washing the plastic member using a solvent in which the osmotic substance dissolves (step S2 in FIG. 22). Since the osmotic substance penetrates into the vicinity of the surface of the plastic member in a cluster form of several tens to several hundreds of nanometers, the surface of the plastic member from which the osmotic substance has been removed by the above-described solvent removal treatment (cleaning treatment) is submicron. From this, nano-order micropores are formed. That is, fine irregularities of submicron to nano order can be formed on the surface of the plastic member. When the surface modification method of the present invention is used, fine irregularities can be formed on the surface of various types of plastic members.

  The “pressurized fluid” in the present specification refers to a pressurized fluid. However, the pressure of the pressurized fluid may be a pressure that sufficiently dissolves the osmotic material, and the “pressurized fluid” referred to here includes not only a fluid pressurized to a critical point (supercritical state) or more, A fluid pressurized at a pressure lower than the critical point is also included. Preferably, it means a fluid pressurized to 5 MPa or more. That is, the “pressurized fluid” in the present specification means not only a supercritical fluid but also a pressurized liquid fluid (liquid) and a pressurized inert gas.

  When a metal film is formed on the surface of a plastic member obtained by the surface modification method of the present invention by electroless plating or the like, the anchor effect due to fine irregularities formed on the surface of the plastic member, the merit of scale by expanding the surface area, etc. Thus, a metal film having excellent adhesion can be formed. In addition, since the irregularities formed on the surface of the plastic member by the surface modification method of the present invention have a size of sub-micron to nano order as described above, they were obtained by the surface modification method of the present invention. When a metal film is formed on the surface of a plastic member, it is possible to form a metal film with excellent smoothness (surface roughness is suppressed) and to form a metal film with excellent electrical characteristics. Can do. Further, by adjusting the content ratio of the micropores formed on the surface of the plastic member, it is possible to control the electrical characteristics such as the dielectric constant and dielectric loss tangent of the plastic member and the optical characteristics such as lowering the refractive index.

  In the surface modification method of the present invention, the penetration of the osmotic material into the surface of the plastic member using the pressurized fluid can be achieved by dissolving the osmotic material in the pressurized fluid and adding the osmotic material dissolved. Preferably, the method includes bringing a pressurized fluid into contact with the plastic member and allowing the osmotic substance to penetrate into the surface of the plastic member.

  Further, in the surface modification method of the present invention, the osmotic substance is infiltrated into the surface of the plastic member using the pressurized fluid, and the solution in which the osmotic substance is dissolved is applied to the surface of the plastic member. It is preferable that the method further comprises bringing a pressurized fluid into contact with the plastic member to which the osmotic material is applied so that the osmotic material penetrates into the surface of the plastic member.

  In the surface modification method of the present invention, the plastic member has a recess, and when the osmotic substance penetrates into the surface of the plastic member, the pressurized fluid is in contact with the plastic member, It is preferable that the opening defined in the surface of the plastic member is closed by the recess, the pressurized fluid is retained in the recess, and the osmotic substance is permeated into the surface of the plastic member defining the recess.

  According to the surface modification method for a plastic member having a concave portion on the surface, fine irregularities can be formed on the surface defining the concave portion of the plastic member, and the physical shape of the surface defining the concave portion is selectively selected. Can be changed. Therefore, when a metal film is formed on the plastic member produced by this surface modification method by electroless plating or the like, an anchor effect on the nano order is selectively obtained only by the surface that defines the concave portion of the plastic member. It is possible to form a metal film having excellent adhesion and smoothness only on the surface defining the recess.

  In the surface modification method of the present invention, the surface modification method is a surface modification method using an injection molding machine including a mold and a heating cylinder that injects a molten resin of a plastic member into the mold. Infiltrating the osmotic material into the surface of the plastic member using the pressurized fluid, introducing the pressurized fluid in which the osmotic material is dissolved into the flow front portion of the molten resin in the heating cylinder; Injection molding of the molten resin into the cavity of the mold.

  In the surface modification method using this injection molding machine, the pressurized fluid in which the osmotic material is dissolved is introduced into the flow front part of the molten resin in the heating cylinder, so the molten resin in the heating cylinder is injected into the mold. Then, first, the molten resin in the flow front portion into which the osmotic material has permeated is injected, and thereafter, the molten resin substantially not osmotically infiltrated is injected and filled into the mold. When the molten resin in the flow front part infiltrated with the osmotic material is injected, the molten resin in the flow front part is pulled to the mold surface by the fountain flow phenomenon (fountain effect) of the flowing resin in the mold. A surface layer (skin layer) is formed in contact with the mold. Therefore, in this surface modification method, a plastic molded article comprising a skin layer in which the penetrating substance is dispersed and a core layer in which the penetrating substance is hardly dispersed is obtained. In the surface modification method using the injection molding machine, the molding process and the surface modification process can be performed simultaneously. Therefore, when this method is used, the osmotic substance can be uniformly distributed only on the surface of various types of plastic molded articles as long as the osmotic substance has a certain degree of solubility in the pressurized fluid. That is, the surface modification method using this injection molding machine can be applied to surface modification techniques for various types of plastic members.

  In the surface modification method of the present invention, a concavo-convex pattern is formed on the cavity-side surface of the mold, the molten resin is injected and filled into the cavity of the mold, the surface has a recess, and the recess When a plastic member having a penetrating substance infiltrated into the surface is molded, and the penetrating substance is dissolved with a solvent and removed from the surface of the plastic member, the solvent penetrates the concave part by contacting only the surface of the concave part. It is preferred to remove the material.

  In the surface modification method of the present invention, the surface modification method is a surface modification method using an extrusion molding machine, and the penetrating substance is permeated into the surface of the plastic member using the pressurized fluid. Bringing the pressurized fluid in which the osmotic substance is dissolved into contact with the molten resin of the plastic member in the extrusion molding machine to infiltrate the osmotic material into the molten resin and extruding the molten resin. Is preferred.

  Even in the surface modification method using the above extrusion molding machine, the pressurized fluid in which the penetrating substance is dissolved is injected into the molten resin in the extrusion molding machine. The surface modification of the member becomes possible. Therefore, the surface modification method using this extrusion molding machine is also applicable to surface modification techniques for various types of plastic members. Moreover, if the surface modification method using the said extrusion molding machine is used, the film-form plastic molded product which carried out surface modification | reformation can also be manufactured continuously. In addition, the injection | pouring substance injection | pouring location in an extrusion molding machine can be provided in arbitrary positions if it is a position in the area | region from a heating cylinder to an extrusion die.

  In the surface modification method of the present invention, the pressure of the pressurized fluid is preferably 5 to 25 MPa. The solubility of the osmotic material in the pressurized fluid increases with increasing pressure. When the pressure is 5 MPa or less, the solubility of the osmotic substance becomes extremely low, and the penetration effect of the osmotic substance on the surface of the plastic member does not appear. Further, when the pressure is 25 MPa or more, the permeability of the pressurized fluid to the plastic member becomes high, and it may be difficult to control the foaming of the plastic member.

  In the surface modification method of the present invention, the pressurized fluid is preferably carbon dioxide. In the surface modification method of the present invention, when carbon dioxide is used as the pressurized fluid, supercritical carbon dioxide, subcritical carbon dioxide, liquid carbon dioxide, or gaseous carbon dioxide can be used as the pressurized fluid. However, the present invention is not limited to this. As the pressurized fluid, any medium can be used as long as it is a medium that dissolves the osmotic material to some extent. For example, air, water, butane, pentane, methanol, or the like may be used as the pressurized fluid. As the pressurized fluid for dissolving the osmotic substance, supercritical carbon dioxide, which has a solubility in organic materials comparable to hexane, is non-polluting, and has high affinity for plastic members, is particularly preferable. Further, a small amount of an organic solvent such as ethanol may be mixed as an entrainer in order to improve the solubility of the penetrating substance in the pressurized fluid.

  In the surface modification method of the present invention, the plastic member is preferably formed of any one of a thermoplastic resin, a thermosetting resin, and a photocurable resin. As described above, the surface modification method of the present invention can be applied to various types of plastic members. For example, as a thermoplastic resin, polycarbonate, polymethyl methacrylate, polyetherimide, polymethylpentene, amorphous Polyolefin, polytetrafluoroethylene, liquid crystal polymer, styrene resin, polymethylpentene, polyacetal, cycloolefin polymer, etc. can be used. Thermosetting resin and photocurable resin include epoxy resin, phenol resin, acrylic resin, silicon Resins, polyimide resins, urethane resins and the like can be used. Moreover, as a plastic member, you may use what mixed the said material, the polymer alloy which has these as a main component, and what mix | blended various fillers with these.

  In the surface modification method of the present invention, the penetrating substance is preferably a water-soluble polymer or a water-soluble monomer. Specifically, as the penetrating substance, polyalkyl glycol is preferable, and polyethylene glycol is more preferable. However, the present invention is not limited to this, and any osmotic substance may be used as long as it shows a certain degree of solubility in the pressurized fluid and is a water-soluble material. For example, polypropylene glycol, polybutylene glycol, polyvinyl alcohol, polyvinyl pyrrolidone, ε-caprolactam, polyol ester and the like may be used. Further, a surfactant such as a polyethylene oxide-polypropylene oxide block copolymer and glycerin fatty acid ester may be used as the penetrating substance.

  In the surface modification method of the present invention, the molecular weight of the penetrating substance is preferably 50 to 2,000. When a material having a molecular weight of 2000 or more is used, the solubility in a pressurized fluid is lowered, and the penetration effect of the penetrating substance on the surface of the plastic member is lowered. In addition, when a material having a molecular weight of 2000 or more is used as the penetrating substance, the flatness of the surface of the plastic member tends to be deteriorated. Particularly, stress is generated when the penetrating substance is extracted (removed) from the plastic member. However, cracks are likely to occur on the surface of the plastic member. In addition, considering the compatibility with the plastic resin, the range of the molecular weight of the penetrating material is preferably the above range.

  In the surface modification method of the present invention, the osmotic material includes a first osmotic material and a second osmotic material, and the first osmotic material can be removed when removing the osmotic material from the surface of the plastic member. preferable.

  According to a second aspect of the present invention, there is provided a method of forming a metal film on the surface of a plastic member, comprising preparing a plastic member impregnated on the surface with a penetrating substance, and contacting the plastic member with a solvent. Forming a metal film comprising: dissolving the osmotic material in the solvent to remove the osmotic material from the surface of the plastic member; and forming a metal film on the surface of the plastic member from which the osmotic material has been removed. A method is provided.

  In the metal film formation method of the present invention, the surface of the plastic member is modified by the surface modification method of the present invention described above (steps S1 ′ and S2 ′ in FIG. 23), and then the surface of the obtained plastic member is obtained. A metal film is formed by electroless plating or the like (step S3 in FIG. 23). Therefore, it is possible to form a metal film with excellent smoothness and adhesion due to the anchor effect due to subtle and unevenness of sub-micron to nano-order size formed on the surface of the plastic member and the scale merit due to the expansion of the surface area. it can. In addition, as described above, since the surface modification method of the present invention can form fine irregularities on the surface of various types of plastic members, the metal film formation method of the present invention can provide surfaces of various types of plastic members. It is possible to form a metal film having excellent smoothness and adhesion.

  In the method for forming a metal film of the present invention, forming the metal film on the surface of the plastic member from which the penetrating material has been removed, providing a plating catalyst nucleus on the surface of the plastic member from which the penetrating material has been removed, It is preferable to include forming a metal film on the surface of the plastic member provided with the plating catalyst nucleus by an electroless plating method.

  In the method for forming a metal film of the present invention, preparing a plastic member having the surface impregnated with the osmotic material comprises dissolving the osmotic material in a pressurized fluid and bringing the pressurized fluid into contact with the plastic member. Preferably, the osmotic substance is allowed to penetrate into the surface of the plastic member.

  In the method for forming a metal film of the present invention, preparing a plastic member having a surface impregnated with the osmotic material comprises applying a solution in which the osmotic material is dissolved to the surface of the plastic member, and applying the osmotic material. It is preferable to include contacting the plastic member with a pressurized fluid to infiltrate the penetrating substance into the surface of the plastic member.

  In the method for forming a metal film of the present invention, the plastic member has a recess, and when the osmotic substance penetrates into the surface of the plastic member, the pressurized fluid is in contact with the plastic member, It is preferable that the opening defined in the surface of the plastic member is closed by the recess, the pressurized fluid is retained in the recess, and the osmotic substance is permeated into the surface of the plastic member defining the recess. .

  In the method for forming a metal film according to the present invention, the metal film is formed by using an injection molding machine including a mold and a heating cylinder for injecting a molten resin of a plastic member into the mold. A plastic member having a surface impregnated with the osmotic material is prepared by bringing a pressurized fluid in which the osmotic material is dissolved into contact with a flow front portion of a molten resin in the injection molding machine, It is preferable to include infiltrating the molten resin and injection-filling the molten resin into the mold.

  In the metal film forming method of the present invention, a concavo-convex pattern is formed on the cavity side surface of the mold, the molten resin is injected and filled into the cavity of the mold, the surface has a recess, and the recess When a plastic member having a penetrating substance permeated into the surface of the plastic member was molded, and the penetrating substance was dissolved with a solvent and removed from the surface of the plastic member, the solvent was allowed to contact only the surface of the concave portion and penetrated into the concave portion. It is preferred to remove the osmotic material.

  In the metal film forming method of the present invention, the metal film forming method is a method of forming a metal film using an extrusion molding machine, and preparing a plastic member having a surface impregnated with the penetrating substance is provided as the penetrating material. Preferably, the method includes bringing the pressurized fluid in which the substance is dissolved into contact with the molten resin of the plastic member in the extrusion molding machine to infiltrate the penetrating substance into the molten resin and extruding the molten resin. .

  In the metal film forming method of the present invention, the pressure of the pressurized fluid is preferably 5 to 25 MPa. In the metal film forming method of the present invention, the pressurized fluid is preferably carbon dioxide.

  In the method for forming a metal film of the present invention, the plastic member impregnated on the surface with the osmotic substance is produced using an injection molding machine equipped with a mold, and the plastic member impregnated on the surface with the osmotic substance is prepared. Preparing a plastic sheet impregnated on the surface with the penetrating substance; holding the plastic sheet in a mold of the injection molding machine; and in the mold holding the plastic sheet. It is preferable to include injection molding of the molten resin in the injection molding machine and molding the plastic member. That is, in the metal film forming method of the present invention, a plastic member impregnated on the surface with an osmotic material may be prepared by insert molding.

  In this method of forming a metal film using insert molding, insert molding is performed using a plastic sheet impregnated on the surface with the penetrating substance obtained by the surface modification method of the present invention, and the plastic sheet is injected during insert molding. A plastic molded product integrated with the plastic substrate thus formed is molded. In this method, by controlling the film thickness and the like of the plastic sheet impregnated with the penetrating substance, the penetrating amount and the penetrating depth of the penetrating substance in the plastic molded product after the insert molding can be controlled.

  In the method for forming a metal film of the present invention, the plastic sheet is prepared by using an extrusion molding machine, and a plastic sheet having the surface impregnated with the osmotic material is prepared. Is preferably brought into contact with the molten resin in the extrusion molding machine to allow the penetrating substance to penetrate into the molten resin, and the molten resin is extruded to form the plastic sheet.

  In the metal film forming method of the present invention, preparing a plastic sheet impregnated on the surface with the osmotic material, preparing a plastic film, and preparing a mixed solution containing the osmotic material and the plastic resin And applying the mixed solution on the plastic film to form a resin film in which the penetrating material is dispersed on the plastic film. When a plastic sheet is produced using this method, the layer (membrane) in which the osmotic substance is dispersed can be made thinner, and the amount and distribution of the osmotic substance can be adjusted more easily. This makes it possible to manufacture a stable plastic member.

  In the method for forming a metal film of the present invention, the plastic member impregnated on the surface with the osmotic substance is produced using an injection molding machine equipped with a mold, and the plastic member impregnated on the surface with the osmotic substance is prepared. Preparing a plastic film, preparing a first mixed solution containing metal fine particles and a first plastic resin, preparing a second mixed solution containing the penetrant and the second plastic resin, and The first mixed solution is applied on a plastic film to form a first resin film in which the metal fine particles are dispersed on the plastic film, and the second mixed solution is applied on the first resin film. Forming a second resin film in which the osmotic material is dispersed on the first resin film, and applying the plastic film on which the first and second resin films are formed to the above-mentioned film. It is preferable to include holding in a mold of a molding machine and molding the plastic member by injection-filling molten resin in the injection molding machine into the mold in which the plastic film is held. .

  Further, in the method for forming a metal film of the present invention, the preparation of the plastic member impregnated on the surface with the osmotic substance, the preparation of a plastic film, and the mixed solution containing the osmotic substance, metal fine particles and plastic resin And applying the mixed solution on the plastic film to form a resin film in which the osmotic substance and metal fine particles are dispersed on the plastic film. The forming method is a method of forming a metal film using an injection molding machine equipped with a mold, and the method of forming the metal film further comprises removing the penetrating material and then forming the resin film on which the resin film is formed. The film is held in the mold of the injection molding machine, and the molten tree in the injection molding machine is placed in the mold in which the plastic film is held. It was injection filling preferably includes the method comprising molding the plastic member.

  In the metal film forming method of the present invention, the metal film forming method uses an injection molding machine including a mold and first and second heating cylinders that inject a molten resin of a plastic member into the mold. Forming a plastic member having a surface impregnated with the osmotic material, preparing a first plastic resin containing the osmotic material and a second plastic resin not containing the osmotic material; , Plasticizing and melting the first plastic resin in the first heating cylinder, plasticizing and melting the second plastic resin in the second heating cylinder, and injecting the molten first plastic resin into the mold And after injecting the first plastic resin, the molten second plastic resin is injected and filled into the mold to mold the plastic member. Mukoto is preferable. That is, in the metal film forming method of the present invention, a plastic member having a surface impregnated with a penetrating substance may be prepared by sandwich molding.

  In the metal film forming method of the present invention, the plastic member is preferably formed of any one of a thermoplastic resin, a thermosetting resin, and a photocurable resin.

  In the metal film forming method of the present invention, the penetrating substance is preferably a water-soluble polymer or a water-soluble monomer. In the method for forming a metal film of the present invention, it is particularly preferable that the penetrating material is polyethylene glycol. Moreover, in the method for forming a metal film of the present invention, the molecular weight of the penetrating material is preferably 50 to 2000.

  In the method for forming a metal film of the present invention, the osmotic substance includes a first osmotic substance and a second osmotic substance, and the first osmotic substance is removed when the osmotic substance is removed from the surface of the plastic member. Is preferred. In this case, it is preferable that the first penetrating substance is a water-soluble polymer or a water-soluble monomer. Moreover, it is preferable that the molecular weight of a 1st osmosis | permeation substance is 50-2000.

  According to a third aspect of the present invention, there is provided a method for producing a plastic member, comprising preparing a plastic member having a penetrating substance impregnated on the surface thereof, and contacting the solvent with the plastic member to remove the penetrating substance from the solvent. And dissolving the osmotic material from the surface of the plastic member. In the method for producing a plastic member of the present invention, a plastic member having fine holes (fine irregularities) on the surface and excellent smoothness can be more easily produced for various types of plastics.

  According to the surface modification method of the present invention, fine unevenness of submicron to nano order can be formed on the surface of a plastic member using a pressurized fluid for various types of plastic members. Therefore, for example, when the surface modification method of the present invention is used as an electroless plating pretreatment process, a low-cost and clean electroless plating pretreatment process can be provided.

  According to the method for forming a metal film of the present invention, the metal film is formed on the surface of the plastic member obtained by the surface modification method of the present invention by electroless plating or the like. Therefore, a metal film having excellent adhesion can be formed by an anchor effect due to fine irregularities of nano-order size and a merit of scale due to an increase in surface area. Further, since the unevenness formed on the surface of the plastic member has a size of sub-micron to nano order, it is possible to form a metal film having excellent smoothness (surface roughness is suppressed). Further, according to the method for forming a metal film of the present invention, the surface of the plastic member can be roughened without using a harmful etchant (etching solution) as in the conventional plating method. A forming method can be provided.

  According to the method for producing a plastic member of the present invention, it is possible to easily produce a plastic member having fine pores (fine irregularities) on the surface and excellent smoothness for various types of plastics. Further, by adjusting the content ratio of the micropores formed on the surface of the plastic member, it is possible to control the electrical characteristics such as the dielectric constant and dielectric loss tangent of the plastic member and the optical characteristics such as lowering the refractive index.

  Hereinafter, embodiments of the surface modification method, metal film formation method, and plastic member manufacturing method of the present invention will be described in detail with reference to the drawings. The embodiments described below are preferred specific examples of the present invention. The present invention is not limited to this.

  In Example 1, supercritical carbon dioxide (pressurized fluid) in which a penetrating substance is dissolved is brought into contact with the surface of a plastic member made of a thermoplastic resin so that the penetrating substance penetrates the plastic member, and then penetrates from the plastic member. An example of performing surface modification by removing substances will be described. In Example 1, an example in which a plating film (metal film) is formed on the surface of a surface-modified plastic member will also be described. In this example, polyethylene glycol (molecular weight 200) was used as the penetrating material, and a polycarbonate substrate was used as the plastic member.

[Reformer]
A schematic configuration of the apparatus used for surface modification of the plastic member of this example is shown in FIG. As shown in FIG. 1, the reformer 100 mainly includes a liquid carbon dioxide cylinder 1 and a syringe pump 2 (260D manufactured by ISCO) that generates supercritical carbon dioxide (hereinafter also referred to as supercritical carbon dioxide). ), A dissolution tank 3 for dissolving an osmotic substance in supercritical carbon dioxide, a high-pressure container 4 for housing the plastic member 101, a recovery tank 5 for recovering gas discharged from the high-pressure container 4 and the like, and components thereof It is comprised with the piping 13 which connects. Further, as shown in FIG. 1, manual needle valves 6 to 10 for controlling the flow of pressurized fluid in the reformer 100, a pressure holding valve 11, and a check valve 12 are placed at predetermined positions in the pipe 13. Is provided.

  Note that the high-pressure vessel 4 used in this example is a high-pressure vessel whose temperature can be adjusted by a cartridge heater (not shown), and can be cooled by cooling water flowing in a cooling circuit (not shown). In this example, the capacity of the space 14 in which the plastic member 101 in the high-pressure vessel 4 is mounted is 10 ml.

[Surface modification method]
Next, a method for modifying the surface of the plastic member of this example will be described with reference to FIGS. In the following, the surface modification method of this example will be described from the state in which all the valves in FIG. 1 are closed.

  First, as shown in FIG. 1, a plastic member 101 (polycarbonate substrate) to be subjected to surface modification was mounted in a high-pressure vessel 4 adjusted to a predetermined temperature (120 ° C.). Next, polyethylene glycol as an osmotic material was charged into the dissolution tank 3 having an internal volume of 10 ml. In this example, the amount of polyethylene glycol charged was 1 ml. In addition, since the solubility of polyethylene glycol is low, a support (wet support manufactured by ISCO) was used to increase the contact area of supercritical carbon dioxide.

  Next, liquid carbon dioxide was supplied from the liquid carbon dioxide cylinder 1 to the syringe pump 2 and pressurized, and the pressure was increased so that the pressure gauge 15 showed 15 MPa. This produced supercritical carbon dioxide. Next, the manual needle valve 6 is opened, supercritical carbon dioxide is introduced into the dissolution tank 3 through the check valve 12, the inside of the dissolution tank 3 is pressurized to 15 MPa, and the osmotic substance is dissolved in supercritical carbon dioxide. (Step S11 in FIG. 3). After increasing the pressure, the needle valve 6 was closed again.

  Next, the needle valve 8 is opened, and supercritical carbon dioxide in which an osmotic substance having the same pressure as the pump pressure (15 MPa) is not dissolved is introduced into the high-pressure vessel 4 from the syringe pump 2. Boosted to At this time, supercritical carbon dioxide in which the osmotic substance was not dissolved was filled up to the manual needle valves 9 and 10 through the high-pressure vessel 4, and the pressure gauge 16 displayed 15 MPa. In this example, as shown in FIG. 1, a pressure-holding valve 11 that is adjusted in advance so that the pressure on the primary side becomes 15 MPa is provided on the discharge side of the high-pressure vessel 4 so that supercritical carbon dioxide flows at a constant pressure. I did it. Next, the needle valve 8 was closed, and the pressure in the space 14 in the high-pressure vessel 4 was maintained at 15 MPa. In this way, by increasing the pressure in the high-pressure vessel 4 to 15 MPa in advance, it is possible to introduce the supercritical carbon dioxide in which the osmotic material is dissolved into the high-pressure vessel 4 without pressure loss.

  Next, supercritical carbon dioxide in which the osmotic substance is dissolved is introduced from the dissolution tank 3 into the high-pressure vessel 4, and the plastic member 101 is brought into contact with the supercritical carbon dioxide in which the osmotic substance is dissolved (step S12 in FIG. 3). . Specifically, supercritical carbon dioxide was introduced as follows. First, the manual needle valves 6 and 7 were opened, the syringe pump 2 was switched from pressure control to flow control, and supercritical carbon dioxide in which the osmotic substance in the dissolution tank 3 was dissolved was introduced into the high-pressure vessel 4. The pump flow rate was set to 10 ml / min. Further, the manual needle valve 10 was opened, and supercritical carbon dioxide was allowed to flow (discharged) to the recovery tank 5 for 1 minute. By the above operation, the flow path (pipe, etc.) flowing through the high-pressure vessel 4 and the high-pressure vessel 4 with the pressure kept constant was replaced with supercritical carbon dioxide in which the osmotic substance was dissolved. Thereafter, the needle valves 6 and 7 were closed.

  Next, the needle valve 8 is opened, supercritical carbon dioxide in which the osmotic substance is not dissolved is introduced from the syringe pump 2 into a flow path (pipe, etc.) flowing through the high-pressure vessel 4 and is allowed to flow for 10 seconds at a flow rate of 10 ml / min. The supercritical carbon dioxide in which the osmotic material filled in the pipes and the like was dissolved was transported to a desired position (pressed into the high-pressure vessel 4). Thereby, in the vicinity of the surface of the plastic member 101 mounted in the high-pressure vessel 4, the dissolved concentration of the osmotic substance in the supercritical carbon dioxide can be distributed at a high concentration. In this state, the pressure was maintained for 10 minutes to allow the penetrating substance to penetrate the surface of the plastic member 101.

  Next, the power source of the heater of the high-pressure vessel 4 was turned off, the cooling water was poured, and the high-pressure vessel 4 was cooled to 40 ° C. If the internal pressure of the high-pressure vessel 4 decreases during cooling, foaming may occur on the surface and inside of the plastic member 101. Therefore, it is desirable to maintain the external pressure during cooling. Thereafter, the manual needle valve 8 was closed, and at the same time, the valve 9 was opened, and the high pressure vessel 4 was opened to the atmosphere while collecting the permeating substance and carbon dioxide in the collection tank 5. Thereafter, the plastic member 101 in which the penetrating substance penetrated into the surface was taken out from the high-pressure vessel 4.

  Next, the plastic member 101 impregnated with polyethylene glycol (penetrating substance) inside the surface was immersed in pure water and subjected to ultrasonic cleaning for 1 hour to remove the polyethylene glycol from the plastic member 101 (step S13 in FIG. 3). . By this process, the polyethylene glycol that has permeated the surface of the plastic member 101 is released, and micropores are formed in the part from which the polyethylene glycol has been released. That is, fine holes (fine irregularities) were formed on the surface of the plastic member 101 by the above-described cleaning treatment (the physical shape of the surface was changed). This is shown in FIG. FIG. 2 (a) is an AFM (Atomic Force Microscope) observation image of the surface of the plastic member 101 before the cleaning process, and FIG. 2 (b) is a view of the plastic member 101 after the cleaning process. It is an AFM observation image of the surface. As is apparent from FIGS. 2A and 2B, in this example, it is understood that a large number of fine holes of about 100 to 300 nm are formed on the surface of the plastic member 101 after the cleaning process. It was. In this example, the surface modification of the plastic member 101 was performed as described above, and the plastic member 101 having fine irregularities (fine holes) formed on the surface was obtained.

[Method of forming plating film]
Next, an electroless plating film was formed on the plastic member 101 having fine irregularities formed on the surface produced as described above. Specifically, an electroless plating film was formed as follows. First, the plastic member 101 was degreased using a known conditioner (OPC-370, manufactured by Okuno Pharmaceutical Co., Ltd.). Next, a catalyst (OPC-80 catalyst manufactured by Okuno Pharmaceutical Co., Ltd.) was applied to the plastic member 101 (step S14 in FIG. 3), and then an activator (OPC-500 accelerator manufactured by Okuno Pharmaceutical Co., Ltd.). MX) was used to activate the catalyst. Next, electroless copper plating was performed (step S15 in FIG. 3). The plating solution used was OPC-750 electroless copper manufactured by Okuno Pharmaceutical Co., Ltd. As a result, the plating film formed on the plastic member 101 had no blistering, and the adhesion strength by the tape peeling test was good as described later.

  In Example 2, supercritical carbon dioxide (pressurized fluid) in which an osmotic substance is dissolved is brought into contact with the surface of a plastic member made of a thermosetting resin to infiltrate the osmotic substance into the plastic member. An example will be described in which surface modification is carried out by removing the surface. In the second embodiment, a method for forming a plating film (metal film) on the surface of a plastic member whose surface has been modified will also be described. In this example, polyethylene glycol (molecular weight 200) was used as the penetrating material, and a polyimide substrate was used as the plastic member.

  In this example, as in Example 1, the surface modification of the plastic member was performed using the reforming apparatus shown in FIG. The plastic member surface modification method and metal film formation method in this example were performed in the same manner as in Example 1 except that the temperature of the high-pressure vessel 4 shown in FIG.

  As a result, a large number of fine holes were formed on the surface of the plastic member after the penetrating material was removed by the cleaning treatment, as in Example 1. Further, the plating film formed by electroless plating on the plastic member had no blistering, and as described later, the adhesion strength by the tape peeling test was good.

  In Example 3, supercritical carbon dioxide (pressurized fluid) in which an osmotic substance is dissolved is brought into contact with the surface of a plastic member made of a photocurable resin to infiltrate the osmotic substance into the plastic member. An example will be described in which surface modification is carried out by removing the surface. In Example 3, an example in which a plating film (metal film) is formed on the surface of a surface-modified plastic member will be described. In this example, an ultraviolet curable resin substrate containing polyethylene glycol (molecular weight 200) as the penetrating substance and an epoxy resin material and a curing agent as the plastic member was used.

  In this example, as in Example 1, the surface modification of the plastic member was performed using the reforming apparatus shown in FIG. The plastic member surface modification method and metal film formation method in this example were performed in the same manner as in Example 1 except that the temperature of the high-pressure vessel 4 shown in FIG.

  As a result, a large number of fine holes were formed on the surface of the plastic member after the penetrating material was removed by the cleaning treatment, as in Example 1. Further, the plating film formed by electroless plating on the plastic member had no blistering, and as described later, the adhesion strength by the tape peeling test was good.

  In Example 4, as in Example 1, supercritical carbon dioxide (pressurized fluid) in which an osmotic substance was dissolved was brought into contact with the surface of a plastic member made of a thermoplastic resin to infiltrate the osmotic substance into the plastic member. An example will be described in which the permeation material that has permeated the surface of the plastic member is removed to perform surface modification, and further, a plating film (metal film) is formed on the surface of the surface-modified plastic member by electroless plating. However, in this example, polyethylene glycol (molecular weight 2000) was used as the penetrating material, and a polycarbonate substrate was used as the plastic member.

  In this example, the surface modification of the plastic member and the electroless plating film were formed in the same manner as in Example 1 except that polyethylene glycol (molecular weight 2000) was used as the penetrating material. As the reformer, the apparatus shown in FIG. 1 was used.

  As a result, a large number of fine holes were formed on the surface of the plastic member after the penetrating material was removed by the cleaning treatment, as in Example 1. Further, the plating film formed on the plastic member had no blistering, and as described later, the adhesion strength by the tape peeling test was good.

[Tape peeling test and surface roughness measurement]
A tape peeling test was performed on the plating film obtained by the surface modification method and the plating film formation method of Examples 1 to 4 above to evaluate the adhesion of the plating film. Specifically, the plastic member on which the plating film is formed is cut into 100 equal squares at 1 mm intervals, and a tape peeling test is performed on each of the divided plastic substrates (100 sheets). Thus, the electroless plating characteristics were evaluated. The adhesive tape (No. 405) made by Nichiban Co., Ltd. was used for the tape. The results are shown in Table 1. In addition, the evaluation criteria in Table 1 are as follows.
◎: When the number of peeled sheets is 9 or less ○: When the number of peeled sheets is 10 or more and 29 or less △: When the number of peeled sheets is 30 or more and 59 or less ×: The number of peeled sheets is 60 or more or a plating film is formed If not

  Moreover, the surface roughness of the plating film formed on the surface of the plastic member in Examples 1 to 4 was measured using a stylus type surface roughness measuring device (manufactured by KLA-Tencor). The results are also shown in Table 1. In the measurement of the surface roughness, the arithmetic average roughness (Ra) and ten-point average roughness (Rz) of each plastic substrate were measured.

  As is apparent from the results of the tape peeling test shown in Table 1, all of the plating films formed in Examples 1 to 4 were evaluated as 評 価, and it was found that sufficiently good adhesion strength was obtained. This is presumably because the anchor effect and the like were increased by washing and removing the permeating substance impregnated on the surface of the plastic member to form fine irregularities on the surface of the plastic member.

  Moreover, the surface roughness of the plating film formed on the surface of the plastic member in Examples 1 to 4 is on the order of several tens of nanometers in terms of arithmetic average roughness (Ra), and is several in terms of ten-point average roughness (Rz). It was found to be on the order of 100 nm. Considering that the surface roughness of the plastic member is on the order of several μm to several tens of μm when the surface is roughened by the conventional etching process, the plating film forming method of the present invention uses the conventional method. It can be seen that surface roughening is suppressed and good smoothness is obtained as compared with the electrolytic plating method. When the surface roughness of the metal film is large, the reflectivity and electrical characteristics (resistance, etc.) of the metal film deteriorate, but the plating film forming method of the present invention makes the surface roughness of the substrate very small. Therefore, it is suitable as a method for forming a metal film such as a reflector that requires high reflectivity and a metal film such as a high-frequency electric circuit or an antenna that requires good electrical characteristics.

  In Example 5, an example of a method of forming a plating film (metal film) by modifying the surface of only a concave portion using a pressurized fluid with respect to a plastic member made of a thermoplastic resin having a concave portion on the surface will be described. . In this example, a cycloolefin resin (Zeonex) was used as a material for forming a plastic member, and a plastic member having a recess and a through hole on its surface was produced by known injection molding. In this example, a concave pattern having a width of 50 μm and a depth of 50 μm and a through hole having a diameter of Φ200 μm and a height of 1.0 mm (aspect ratio 1.0 / 0.2 = 5.0) were formed on the surface of the plastic member. In this example, polyethylene glycol (molecular weight 200) was used as the penetrating material, and supercritical carbon dioxide was used as the pressurized fluid.

[Reformer]
A schematic configuration of the apparatus used for surface modification of the plastic member of this example is shown in FIG. As shown in FIG. 4, the reformer 200 mainly superimposes a liquid carbon dioxide cylinder 1, a syringe pump 2 (260D manufactured by ISCO) that generates supercritical carbon dioxide, and an osmotic substance (polyethylene glycol). A dissolution tank 3 that dissolves in carbon dioxide, a mold 4 ′ that can accommodate a plurality of plastic members 201, a recovery tank 5 that recovers gas discharged from the mold 4 ′, and the like, and piping that connects these components 13. Further, as shown in FIG. 4, manual needle valves 6 to 10, a pressure holding valve 11 and a check valve 12 for controlling the flow of pressurized fluid in the reformer 200 are placed in predetermined positions in the pipe 13. Is provided. That is, in the reformer 200 of this example, a mold 4 ′ is used instead of the high-pressure vessel 4 of the reformer 100 used in the first embodiment.

  As shown in FIGS. 4 and 5, the mold 4 ′ is mainly composed of a movable mold 20 and a fixed mold 21, and is opened and closed by a mold clamping device (press piston: not shown). 5 is an enlarged view of a region surrounded by a broken line A in FIG. The press piston is movable by position control by an electric servo motor (not shown). The mold 4 'has a structure that can be adjusted by a cartridge heater (not shown). Further, the mold 4 'in this example can be cooled by cooling water flowing in a cooling circuit (not shown).

  The mold 4 ′ in this example has a structure in which a plurality of plastic members 201 are sandwiched and held between the movable mold 20 and the fixed mold 21 as shown in FIGS. 4 and 5. As shown in FIGS. 4 and 5, a plurality of recesses 20 a are formed on the surface of the movable mold 20 on the fixed mold 21 side so as to follow the outer shape of the upper half of the plastic member 201. On the surface of the mold 20, a plurality of recesses 21 a are formed that follow the outer shape of the lower half of the plastic member 201. And the recessed part 20a of the movable metal mold | die 20 and the recessed part 21a of the fixed metal mold | die 21 are arrange | positioned in the position which mutually opposes. That is, when the movable mold 20 and the fixed mold 21 are closed, the concave portion 20a of the movable mold 20 and the concave portion 21a of the fixed mold 21 are formed at the interface between the fixed mold 21 and the movable mold 20. The plastic member 201 has a structure in which a plurality of spaces (hereinafter also referred to as cavities) having substantially the same dimensions and shapes as the outer dimensions and shapes of the plastic member 201 are defined. Therefore, when the plastic member 201 is attached to the interface between the movable mold 20 and the fixed mold 21 and the mold is closed, the recesses 202 formed on the surface of the plastic member 201 and the openings of the through holes 203 (recesses and The opening defined on the surface of the plastic member 201 by the through hole) is closed by the mold.

  In addition, as shown in FIG. 4, the mold 4 ′ has an inlet 23 for introducing supercritical carbon dioxide into a space defined between the movable mold 20 and the fixed mold 21, and the mold 4. A discharge port 24 through which supercritical carbon dioxide is discharged from is formed. Further, the initial die opening amount 22 of the press piston in this embodiment was set to 1 mm (see FIG. 5).

[Surface modification method]
A method for modifying the surface of a plastic member in Example 5 will be described with reference to FIGS. In the following, the surface modification method of this example will be described from the state in which all the valves in FIG. 4 are closed.

  First, a plastic member 201 was produced by known injection molding, and the plastic member 201 was irradiated with UV light for 1 minute by a low-pressure mercury lamp having a wavelength of 185 nm. Thereby, the surface of the plastic member 201 was hydrophilized, and the affinity between the penetrating material polyethylene glycol and the plastic member 201 was increased. Next, as shown in FIG. 4, a plurality of plastic members 201 were mounted in a mold 4 ′ adjusted to a predetermined temperature (120 ° C.).

  Next, polyethylene glycol as an osmotic material was charged into the dissolution tank 3 having an internal volume of 10 ml. In this example, the amount of polyethylene glycol charged was 1 ml. In addition, since the solubility of polyethylene glycol in carbon dioxide is low, a support (wet support manufactured by ISCO) was used to increase the contact area of supercritical carbon dioxide.

  Next, liquid carbon dioxide was supplied from the liquid carbon dioxide cylinder 1 to the syringe pump 2 and pressurized, and pressure was increased so that the pressure gauge 15 showed 15 MPa to generate supercritical carbon dioxide. Next, the manual needle valve 6 is opened, supercritical carbon dioxide is introduced into the dissolution tank 3 through the check valve 12, the inside of the dissolution tank 3 is pressurized to 15 MPa, and the osmotic substance is dissolved in supercritical carbon dioxide. (Step S51 in FIG. 6). After increasing the pressure, the needle valve 6 was closed again.

  Next, the needle valve 8 is opened, and supercritical carbon dioxide in which an osmotic substance having the same pressure (15 MPa) as the pump pressure is not dissolved is introduced from the syringe pump 2 into the cavity of the mold 4 ′. The inside was pressurized to 15 MPa. At this time, the supercritical carbon dioxide in which the osmotic material was not dissolved was filled up to the manual needle valves 9 and 10 through the mold 4 ′, and the pressure gauge 16 displayed 15 MPa. In this example, as shown in FIG. 4, a pressure-holding valve 11 that is adjusted in advance so that the pressure on the primary side becomes 15 MPa is provided on the discharge side of the mold 4 ′ so that supercritical carbon dioxide flows at a constant pressure. I tried to do it. Next, the needle valve 8 was closed, and the pressure of the cavity in the mold 4 ′ was maintained at 15 MPa. Thus, by raising the pressure in the mold 4 ′ to 15 MPa in advance, it is possible to introduce supercritical carbon dioxide in which the osmotic material is dissolved into the mold 4 ′ without pressure loss.

  Next, supercritical carbon dioxide in which the osmotic material is dissolved is introduced from the dissolution tank 3 into the mold 4 ′, and the supercritical carbon dioxide in which the osmotic material is dissolved is brought into contact with the plastic member 201 (step S52 in FIG. 6). ). Specifically, supercritical carbon dioxide in which an osmotic substance was dissolved was introduced as follows. First, the manual needle valves 6 and 7 were opened, the syringe pump 2 was switched from pressure control to flow control, and supercritical carbon dioxide in which the osmotic substance in the dissolution tank 3 was dissolved was introduced into the mold 4 '. The pump flow rate was set to 10 ml / min. Further, the manual needle valve 10 was opened, and supercritical carbon dioxide was allowed to flow (discharged) into the recovery tank 5 for 1 minute. By the above operation, the flow path (pipe, etc.) flowing through the mold 4 ′ and the mold 4 ′ with the pressure kept constant was replaced with supercritical carbon dioxide in which the osmotic material was dissolved. Thereafter, the needle valves 6 and 7 were closed.

  Next, the needle valve 8 is opened, supercritical carbon dioxide in which the osmotic substance is not dissolved is introduced from the syringe pump 2 into a flow path (pipe, etc.) flowing through the mold 4 ′, and is allowed to flow for 10 seconds at a flow rate of 10 ml / min. Then, the supercritical carbon dioxide in which the penetrating substance filled in the piping and the like was dissolved was transported to a desired position (pressed into the mold 4 ′). As a result, in the vicinity of the surface of the plastic member 201 mounted in the mold 4 ′, the dissolved concentration of the osmotic substance in the supercritical carbon dioxide can be distributed at a high concentration.

  Next, in a state where the supercritical carbon dioxide is in contact with the plastic member 201, the mold 4 ′ is closed, and the recess 202 of the plastic member 201 and the opening of the through hole 203 are closed, and the supercritical carbon dioxide in which the permeation substance is dissolved. Was retained only in the recess 202 and the through hole 203 (step S53 in FIG. 6). Specifically, the press piston is raised and the plastic member 201 is pressed to close the mold 4 ′, and selectively penetrate the surface of the plastic member 201 that defines the recess 202 and the through hole 203. Of dissolved supercritical carbon dioxide was contacted. At this time, the penetrating material penetrates into the inside of the surface of the plastic member 201 that defines the recess 202 and the through hole 203 together with the supercritical carbon dioxide. In this example, this state was maintained for 10 minutes, and the permeating substance was permeated into the surface of the plastic member 201 defining the concave portion 202 and the through hole 203. When this method is used, the penetrating substance can be uniformly permeated at a high concentration only on the surface of the plastic member 201 that defines the concave portion 202 and the through hole 203 of the plastic member 201.

  In this example, the supercritical carbon dioxide in which the osmotic substance is dissolved is introduced into the mold 4 ′ and the mold 4 ′ is closed until the recess 202 of the plastic member 201 and the opening of the through hole 203 are closed. Since the steps (steps S52 to S53 in FIG. 6) are performed in a short time (5 to 10 seconds in this example), the surface of the plastic member 201 other than the concave portion 202 and the through hole 203 is almost penetrated. The substance does not penetrate. However, if the time from the introduction of supercritical carbon dioxide in which the osmotic substance is dissolved into the mold 4 ′ to the closing of the mold 4 ′ is increased, the osmotic substance dissolved in the supercritical carbon dioxide is removed from the recess 202 and the through hole. Since there is a risk of permeating into a surface other than 203 at a high concentration, the process from introduction of supercritical carbon dioxide in which a penetrating substance is dissolved into the mold 4 ′ to closing the mold 4 ′ is as short as possible. It is preferable to carry out within.

  Next, the power source of the heater of the mold 4 'was turned off, the cooling water was poured, and the mold 4' was cooled to 40 ° C. Note that if the internal pressure of the mold 4 ′ is reduced during cooling, foaming may occur on the surface and inside of the plastic member 201. Therefore, it is desirable to maintain the external pressure during cooling. Thereafter, the manual needle valve 8 was closed, and at the same time, the valve 9 was opened, and the mold 4 ′ was opened to the atmosphere while collecting the permeating substance and carbon dioxide in the collection tank 5. Next, the plastic member 201 was taken out from the mold 4 '.

  Next, the polyethylene glycol was removed from the plastic member 201 in which the surface of the recess 202 and the through hole 203 was impregnated with polyethylene glycol by the above method (step S54 in FIG. 6). Specifically, the plastic member 201 impregnated with polyethylene glycol on the surface was immersed in pure water and ultrasonic cleaning was performed for 1 hour. By this cleaning process, the polyethylene glycol that has permeated the surfaces of the recesses 202 and the through holes 203 of the plastic member 201 is removed, and fine irregularities are formed on the surfaces of the recesses 202 and the through holes 203 of the plastic member 201. That is, by this cleaning process, the physical shape of the surface was selectively changed only on the surface of the concave portion 202 and the through hole 203 of the plastic member 201. Thus, in this example, the surface modification of the plastic member 201 was performed, and the plastic member 201 in which only the surface defining the concave portion 202 and the through hole 203 was modified was obtained.

[Method of forming plating film]
Next, electroless plating was performed on the plastic member 201 produced by the surface modification method in the same manner as in Example 1 to form a plating film on the surface of the plastic member 201 (Steps S55 and S56 in FIG. 6). ). As a result, in this example, the metal film was formed only on the surface defining the recess 202 and the through hole 203 of the plastic member 201. Moreover, like the plating films formed in Examples 1 to 4, the plating film formed in this example had no blistering, and the adhesion strength by the tape peeling test was good.

  Moreover, when the surface roughness of the plating film formed in this example was measured with a stylus type surface roughness measuring device (manufactured by KLA-Tencor), the arithmetic average roughness (Ra) was 21.0 nm, The point average roughness (Rz) is 149.3 nm, which is an extremely small value compared to the plating film (Ra≈several μm to several tens μm) formed by the conventional plating method (etching method), and good surface roughness. (Good smoothness) was obtained. That is, in this example, a plastic molded product having an electroless plating film with high adhesion and smoothness formed on the surface could be obtained.

  In Example 6, as in Example 5, only the recesses and the through holes were surface-modified and a plating film (metal film) was formed on the thermoplastic resin plastic member having the recesses and the through holes on the surface. An example of how to do this will be described. However, in this example, after the solution containing the osmotic substance is applied to the surface of the plastic member, the osmotic substance is dissolved in the supercritical carbon dioxide by contacting the supercritical carbon dioxide (pressurized fluid), and the supercritical carbon dioxide In addition, an example in which the osmotic substance penetrates into the surface of the plastic member will be described.

  In this example, a plastic member having a recess and a through hole on its surface was produced by a known injection molding using a cycloolefin resin (Zeonex) as a plastic member forming material. In this example, a concave pattern having a width of 50 μm and a depth of 50 μm and a through hole having a diameter of Φ200 μm and a height of 1.0 mm (aspect ratio 1.0 / 0.2 = 5.0) were formed on the surface of the plastic member. In this example, polyethylene glycol (molecular weight 600) was used as the penetrating substance.

[Reformer]
FIG. 7 shows a schematic configuration of the reforming apparatus used for modifying the surface of the plastic member in this example. As shown in FIG. 7, the reformer 300 of this example mainly includes a liquid carbon dioxide cylinder 1, a high-pressure pump 33 that generates supercritical carbon dioxide, a mold 4 ′ that houses a plastic member 301, It is comprised by the collection tank 5 which collect | recovers the gas discharged | emitted from metal mold | die 4 'etc., and the piping 13 which connects those components. Further, as shown in FIG. 7, manual needle valves 8 to 10, a pressure holding valve 11, and a check valve 12 for controlling the flow of pressurized fluid in the reformer 300 are placed in predetermined positions in the pipe 13. Is provided.

  As is clear from FIG. 7, in the reformer 300 used in this example, a high-pressure pump 33 was used instead of the syringe pump 2 of the reformer 200 (see FIG. 4) used in the fifth embodiment. Further, the reforming apparatus 300 used in this example is configured such that the dissolution tank 3 of the reforming apparatus 200 of Example 5 is not provided. The mold 4 'used in the reformer 300 of this example has the same structure as that of Example 5, and the initial mold opening 22 of the press piston was set to 1 mm (see FIG. 8 described later).

[Surface modification method]
A method for modifying the surface of the plastic member in the present embodiment will be described with reference to FIGS. In the following, the surface modification method of this example will be described from the state in which all the valves in FIG. 7 are closed.

  First, the plastic member 301 was irradiated with UV light for 1 minute by a low-pressure mercury lamp having a wavelength of 185 nm. Thereby, the surface of the plastic member 301 was hydrophilized, and the affinity between the penetrating polyethylene glycol and the plastic member 301 was increased. Next, polyethylene glycol (molecular weight 600) was heated to 60 ° C. to form a solution, and the solution (304 in FIG. 8) was applied to the surface of the plastic member 301 (plastic) (step S61 in FIG. 11). The polyethylene glycol (molecular weight 600) used in this example is a semi-solid substance at room temperature and a liquid substance at high temperature.

  Next, as shown in FIGS. 7 and 8, the plastic member 301 having the surface coated with the osmotic substance solution 304 was mounted in a mold 4 ′ adjusted to a predetermined temperature (120 ° C.). Next, liquid carbon dioxide was supplied from the liquid carbon dioxide cylinder 1 to the high pressure pump 33 and pressurized, and the pressure was increased so that the pressure gauge 15 showed 15 MPa to generate supercritical carbon dioxide. Next, by opening the manual needle valves 8 and 10, 15 MPa of supercritical carbon dioxide is introduced into the mold 4 ′ and the piping through the reverse support valve 12, and the supercritical carbon dioxide is brought into contact with the plastic member 301. (Step S62 in FIG. 11). Here, on the discharge side of the mold 4 ′, a pressure holding valve 11 in which the pressure on the primary side is adjusted to 15 MPa in advance is provided as in the present embodiment, so that supercritical carbon dioxide flows at a constant pressure. desirable.

  Next, in a state where the surface of the plastic member 301 is in contact with the supercritical carbon dioxide, the mold 4 ′ is closed, the recess 302 of the plastic member 301 and the opening of the through hole 303 are closed, and the supercritical carbon dioxide is recessed. It was made to stay only in 302 and the through hole 303 (state of FIG. 9, step S63 in FIG. 11). In this example, this state was maintained for 10 minutes.

  At this time, supercritical carbon dioxide is allowed to stay only in the recess 302 and the through hole 303 of the plastic member 301, so that the supercritical carbon dioxide passes through the solution 304 applied to the surface of the plastic member 301. Contact the surface of the plastic member 301 defining 302. Thereby, the surface of the plastic member 301 which is a thermoplastic resin swells, the viscosity falls, and it softens. At the same time, the surface of the plastic member 301 in which the liquid penetrating material 304 (polyethylene glycol) applied to the surface of the plastic member 301 is dissolved in supercritical carbon dioxide and defines the recess 302 and the through hole 303 together with the supercritical carbon dioxide. Penetrate inside. When this method is used, the penetrating substance can be uniformly permeated at a high concentration only on the surface of the plastic member 301 that defines the recess 302 and the through hole 303 of the plastic member 301.

  In this example, the process from the introduction of supercritical carbon dioxide into the mold 4 ′ to the closing of the mold 4 ′ to block the recess 302 of the plastic member 301 and the opening of the through hole 303 (in FIG. 11). Steps S62 to S63) are performed in a short time (5 to 10 seconds in this example), so that the penetrating substance hardly penetrates the surfaces other than the concave portion 302 and the through hole 303 of the plastic member 301. However, if the time from introduction of supercritical carbon dioxide into the mold 4 ′ to closing of the mold 4 ′ is lengthened, the permeation substance dissolved in the supercritical carbon dioxide is applied to the surface other than the recess 302 and the through hole 303. Therefore, it is preferable to carry out the process from the introduction of supercritical carbon dioxide into the mold 4 ′ to the closing of the mold 4 ′ within as short a time as possible.

  Next, the power source of the heater of the mold 4 'was turned off, the cooling water was poured, and the mold 4' was cooled to 40 ° C. Note that if the internal pressure of the mold 4 ′ decreases during cooling, foaming may occur on the surface and inside of the plastic member 301. Therefore, it is desirable to maintain the external pressure during cooling. Thereafter, the manual needle valve 8 was closed, and at the same time, the valve 9 was opened, and the mold 4 ′ was opened to the atmosphere while collecting the permeating substance and carbon dioxide in the collection tank 5 (state of FIG. 10). Thereafter, the plastic member 301 in which the penetrating substance 305 penetrated the surface was taken out from the mold 4 '.

  Next, the penetrating substance 305 was removed from the plastic member 301 impregnated with the penetrating substance 305 (polyethylene glycol) only on the surface defining the recess 302 and the through hole 303 by the above method (step S64 in FIG. 11). Specifically, the plastic member 301 was immersed in pure water and ultrasonic cleaning was performed for 1 hour. As a result, the polyethylene glycol that has permeated the surfaces defining the recesses 302 and the through holes 303 of the plastic member 301 is released, and fine irregularities (holes) are formed on the surface. That is, the physical shape of only the surface that defines the concave portion 302 and the through hole 303 of the plastic member 301 was selectively changed by the cleaning process. Thus, in this example, the surface modification of the plastic member 301 was performed, and the plastic member 301 in which only the surface defining the recess 302 and the through hole 303 was modified was obtained.

[Method of forming plating film]
Next, electroless plating was performed on the plastic member 301 produced by the surface modification method in the same manner as in Example 1 to form a plating film on the surface of the plastic member 301 (Steps S65 and S66 in FIG. 11). ). As a result, in this example, the metal film was formed only on the surface defining the recess 302 and the through hole 303 of the plastic member 301. Moreover, like the plating films formed in Examples 1 to 4, the plating film formed in this example had no blistering, and the adhesion strength by the tape peeling test was good.

  Further, when the surface roughness of the plating film formed in this example was measured with a stylus type surface roughness measuring apparatus (manufactured by KLA-Tencor), the arithmetic average roughness (Ra) was 25.6 nm, The point average roughness (Rz) is 179.8 nm, which is an extremely small value compared to a plating film (Ra≈several μm to several tens μm) formed by the conventional plating method (etching method), and good surface roughness. (Good smoothness) was obtained. That is, in this example, a plastic molded product having an electroless plating film with high adhesion and smoothness formed on the surface could be obtained.

  In Example 7, a plastic molded article (plastic member) is molded by injection molding, and at the same time, the osmotic substance is infiltrated into the plastic member using a pressurized fluid, and then the osmotic substance is removed from the plastic member to perform surface modification. An example of a surface modification method and a method of forming a plating film (metal film) on the surface of a plastic member obtained by the surface modification method will be described.

  In this example, polycarbonate, which is a thermoplastic resin, was used as the material for forming the plastic member, and polyethylene glycol having a molecular weight of 200 was used as the penetrating material. Supercritical carbon dioxide was used as the pressurized fluid.

[Molding equipment]
A schematic configuration of the molding apparatus used in this example is shown in FIG. As shown in FIG. 12, the molding apparatus 400 used in this example includes an injection molding machine unit 401 and a supercritical fluid generator unit 402.

  As shown in FIG. 12, the injection molding machine unit 401 mainly includes a plastic cylinder 40 that injects molten resin, a movable mold 43, and a fixed mold 44. In the mold 42, the movable mold 43 and the fixed mold 44 are abutted to form a disk-shaped cavity 45 having a spool at the center. In this example, as shown in FIG. 12, the shape of the region other than the portion (spool or the like) corresponding to the center of the cavity 45 on the surface of the movable die 43 and the stationary die 44 on the cavity 45 side is flat ( Mirror surface). Moreover, as shown in FIG. 12, the gas introduction mechanism 41 was provided in the side part of the flow front part 56 in the heating cylinder 40 (plasticization cylinder). Other structures are the same as those of a conventional injection molding machine.

  As shown in FIG. 12, the supercritical fluid generator 402 mainly includes a liquid carbon dioxide cylinder 1, a continuous flow system 47 (E-260 manufactured by ISCO) consisting of two known syringe pumps, and an osmotic substance. Are dissolved in supercritical carbon dioxide, and each component is connected by a pipe 52. Further, as shown in FIG. 12, the dissolution tank 46 is connected to the gas introduction mechanism 41 of the injection molding machine unit 401 through air operated valves 50 and 51.

[Injection molding method and surface modification method]
Next, the shaping | molding method and surface modification method of this example are demonstrated using FIGS. First, liquid carbon dioxide of 5 to 7 MPa stored in the liquid carbon dioxide cylinder 1 is introduced into the continuous flow system 47 and pressurized to generate supercritical carbon dioxide (pressurized fluid). In the continuous flow system 47, carbon dioxide is constantly pressurized and held at a predetermined pressure of 10 MPa by at least one syringe pump. Next, supercritical carbon dioxide was introduced from the continuous flow system 47 into the dissolution tank 46 to dissolve the osmotic material in supercritical carbon dioxide (step S71 in FIG. 14). The melting tank 46 is heated to 40 ° C., and the dissolving tank 46 is charged with supersaturated polyethylene glycol, which is an osmotic substance. Therefore, in the dissolution tank 46, the permeation substance is always saturated and dissolved in the supercritical carbon dioxide introduced from the continuous flow system 47. At this time, the pressure gauge 48 of the dissolution tank 46 was displayed at 10 MPa. Since the solubility of polyethylene glycol in carbon dioxide is low, in this example, a support (wet support manufactured by ISCO) was used to increase the contact area of supercritical carbon dioxide.

  Next, the screw 53 in the heating cylinder 40 is rotated in the same manner as in the prior art, and the supplied resin pellets 54 are plasticized and melted (step S72 in FIG. 14), and the molten resin is applied to the front 59 of the screw 53. The screw 53 was retracted while being pushed out and weighed, and stopped at a predetermined weighing position. Next, the screw 53 was further retracted, and the internal pressure of the measured molten resin was reduced. In this example, the internal pressure monitor 55 of the molten resin provided in the vicinity of the flow front portion 56 of the heating cylinder 40 confirmed that the resin internal pressure decreased to 4 MPa or less.

  Next, supercritical carbon dioxide in which the osmotic material is dissolved is introduced into the molten resin in the flow front portion 56 of the heating cylinder 40 via the gas introduction mechanism 41, and the supercritical carbon dioxide in which the osmotic material is dissolved is converted into the molten resin. Contact was made (step S73 in FIG. 14). Specifically, supercritical carbon dioxide in which an osmotic material was dissolved was introduced as follows. First, the first air operated valve 50 is opened, and supercritical carbon dioxide in which an osmotic substance is dissolved is introduced into a pipe 52 between the second air operated valve 51 and the first air operated valve 50 to introduce a pressure gauge. 49 was boosted. Next, at the time of introduction into the heating cylinder 40, the second air operated valve 51 is opened with the first air operated valve 50 closed, and the supercritical carbon dioxide in which the osmotic material is dissolved is passed through the gas introduction mechanism 41. It was introduced into the molten resin in a reduced pressure state in the heating cylinder 40 and allowed to penetrate. In this example, the amount of supercritical carbon dioxide introduced was controlled by the internal volume of the pipe 52a. The supercritical fluid that permeates the molten resin may be single as in this example, or may be plural.

  Next, the screw 53 was moved forward by back pressure, and the screw 53 was returned to the filling start position. By this operation, the carbon dioxide and the osmotic material were diffused into the molten resin at the flow front portion 56 in front of the screw 53. Next, the air piston 57 is driven to open the shutoff valve 58, and the molten resin is injected and filled into the cavity 45 of the mold 42 defined by the movable mold 43 and the fixed mold 44 (in FIG. 14). Step S74).

  FIG. 13 schematically shows the state of filling of the molten resin in the mold 42 during injection filling. FIG. 13A is a schematic diagram at the time of initial filling, and at the time of initial filling, the molten resin 56 ′ of the flow front portion 56 is filled, and the osmotic material and carbon dioxide that permeate it are diffused into the cavity 45 while decompressing. . At this time, the molten resin 56 ′ of the flow front portion 56 flows while in contact with the mold surface by the fountain effect at the time of filling to form a skin layer 403.

  Next, when the injection filling is completed, as shown in FIG. 13 (b), a skin layer 403 impregnated with a penetrating substance is formed on the surface of the plastic member (molded product). A core layer 404 is formed that is substantially impermeable to material. Therefore, in the molding method of this example, since the osmotic material that has penetrated into the molded product does not contribute to the surface function, the amount of the osmotic material used can be reduced. In addition, when the holding pressure of the molten resin pressure is increased after the above-described primary filling, foaming of a molded product due to gasification of carbon dioxide can be suppressed. In the molding method of the present embodiment, supercritical carbon dioxide is infiltrated only into the flow front portion in the plasticizing cylinder, so that the absolute amount of carbon dioxide is small relative to the total amount of the filled resin. Therefore, even if the counter pressure is not added to the cavity 45 of the mold 42, the surface property of the plastic member is hardly deteriorated. In this example, the plastic member was molded as described above, and a penetrating substance was infiltrated into the surface.

  Next, the plastic member impregnated with the penetrating substance (polyethylene glycol) on the surface was subjected to ultrasonic cleaning in pure water for 1 hour to remove the penetrating substance impregnated on the surface of the plastic member (step S75 in FIG. 14). ). By this cleaning treatment, fine irregularities (micropores) were formed on the surface of the plastic member. That is, the surface shape of the plastic member was physically changed by the cleaning treatment. Thus, in this example, the surface modification of the plastic member was performed.

[Method of forming plating film]
Next, electroless plating was applied to the plastic member produced by the surface modification method in the same manner as in Example 1 to form a plating film on the surface of the plastic member (Steps S76 and S77 in FIG. 14). As a result, like the plating films formed in Examples 1 to 4, the plating film formed in this example had no blistering, and the adhesion strength by the tape peeling test was good.

  Further, when the surface roughness of the plated film formed in this example was measured with a stylus type surface roughness measuring device (manufactured by KLA-Tencor), the arithmetic average roughness (Ra) was 15.2 nm, The point average roughness (Rz) is 105.8 nm, which is very small compared to the plating film (Ra≈several to several tens of μm) formed by the conventional plating method (etching method), and has a good surface roughness. (Good smoothness) was obtained. That is, in this example, a plastic member having an electroless plating film having excellent adhesion and smoothness formed on the surface could be obtained.

  In Example 8, as in Example 7, the plastic member was molded by injection molding, and at the same time, the osmotic material was infiltrated into the plastic member using a pressurized fluid, and then the osmotic material was removed from the plastic member to modify the surface. An example of a surface modification method for performing the process and a method for forming a plating film (metal film) on the surface of a plastic member obtained by the surface modification method will be described. However, in this example, a method will be described in which a plastic member having irregularities on the surface is molded, only the recesses of the plastic member are surface-modified, and a plating film is formed on the recesses.

  In this example, polycarbonate, which is a thermoplastic resin, was used as the material for forming the plastic member, and polyethylene glycol having a molecular weight of 200 was used as the penetrating material. Supercritical carbon dioxide was used as the pressurized fluid.

[Molding equipment]
As the molding apparatus used in this example, an apparatus having substantially the same configuration as the molding apparatus used in Example 7 (FIG. 12) was used. In the molding apparatus of this example, a stamper having a line-and-space concavo-convex pattern was attached to the surface of the fixed mold 43 on the cavity 45 side. Other than that, the structure was the same as that of the molding apparatus used in Example 7.

[Injection molding method and surface modification method]
First, in the same manner as in Example 7, a plastic member having a surface impregnated with a penetrating material was produced. Next, the opening of the concave portion of the plastic member was closed, and pure water heated to 80 ° C. was allowed to flow only in the concave portion for 1 hour, so that only the permeated material that permeated the surface defining the concave portion was removed. By this cleaning treatment, only polyethylene glycol that had permeated the surface defining the concave portion of the plastic member was detached, and fine irregularities (micropores) were formed on the surface. That is, the physical shape of only the surface defining the concave portion of the plastic member was selectively changed by the cleaning process. Thus, the surface-modified plastic member of this example was obtained.

  Various methods can be considered as the method for cleaning the concave portion. In this example, the concave portion was cleaned as follows. First, a mold having two surfaces, that is, a mold surface to which a stamper having a line-and-space concavo-convex pattern was attached and a mirror-shaped mold surface was prepared. In addition, in this metal mold | die, the metal mold | die of the structure which can move between the metal mold | die surface which attached the stamper which has an uneven | corrugated pattern, and a mirror-shaped metal mold | die inside a cavity was used. Next, a plastic member having a concave portion on the surface and infiltrated with a penetrating material was molded using a mold surface provided with a stamper having a line-and-space uneven pattern (primary molding). Next, the plastic member was moved so that the concave portion of the plastic member faces the mirror-shaped mold surface. Next, the plastic member was pressed with a mirror-shaped mold surface to close the opening of the concave portion of the plastic member. Next, pure water was allowed to flow only in the closed recesses to remove only the penetrating material that had permeated the surface defining the recesses. However, the method of closing the opening of the concave portion of the plastic member is not limited to this, and for example, the opening may be closed by the following method. First, two surfaces, a mold surface to which a stamper having a concavo-convex pattern is attached and a mirror-shaped mold surface are provided on a movable mold, and a concave surface is provided on the surface using a mold surface to which a stamper having a concavo-convex pattern is attached. And the plastic member which the osmosis | permeation substance penetrate | penetrated is shape | molded. Next, the mirror-shaped mold surface of the movable mold may be moved to a position facing the surface of the plastic member, and the plastic member may be pressed with the mirror-shaped mold surface to close the opening of the concave portion of the plastic member. In addition, a first mold having a mold surface to which a stamper having a concavo-convex pattern is attached and a second mold having a mirror-shaped mold surface are prepared separately, and a recess is formed on the surface using the first mold. After the plastic member having the penetrating material and the penetrating substance is molded, the plastic member may be transferred to the second mold, and the opening of the concave portion of the plastic member may be closed with the mirror-shaped mold surface.

[Method of forming plating film]
Next, electroless plating was applied to the plastic member produced by the surface modification method in the same manner as in Example 1 to form a plating film on the surface of the plastic member. In this example, only the surface that defines the concave portion of the plastic member is surface-modified to form fine irregularities. Therefore, in this example, the plating film is formed only on the surface that defines the concave portion of the plastic member. It was. Moreover, like the plating films formed in Examples 1 to 4, the plating film formed in this example had no blistering, and the adhesion strength by the tape peeling test was good.

  Further, when the surface roughness of the plating film formed in this example was measured with a stylus type surface roughness measuring device (manufactured by KLA-Tencor), the arithmetic average roughness (Ra) was 15.8 nm, The point average roughness (Rz) is 120.8 nm, which is a very small value compared to the plating film (Ra≈several μm to several tens μm) formed on the plastic substrate by the conventional plating method (etching method). Thus, a good surface roughness (good smoothness) was obtained. That is, in this example, a plastic member having an electroless plating film having excellent adhesion and smoothness formed on the surface could be obtained.

  In Example 9, as in Example 7, the plastic member was molded by injection molding, and at the same time, the osmotic material was infiltrated into the plastic member using a pressurized fluid, and then the osmotic material was removed from the plastic member to modify the surface. An example of a surface modification method for performing the process and a method for forming a plating film (metal film) on the surface of a plastic member obtained by the surface modification method will be described. However, in this example, two different types of osmotic substances were dissolved in the pressurized fluid, and the two types of osmotic substances were infiltrated into the surface of the plastic member. For the two osmotic substances, ε-caprolactam having a molecular weight of 113.16 (first osmotic substance) which is a water-soluble polymer and hexafluoroacetylacetonato palladium (II) (second osmotic substance) which is a metal complex are used. It was. Also, polycarbonate, which is a thermoplastic resin, was used as the plastic member forming material, and supercritical carbon dioxide was used as the pressurized fluid.

[Molding equipment]
As the molding apparatus used in this example, an apparatus having substantially the same configuration as that of the molding apparatus used in Example 7 (FIG. 12) was used. In the molding apparatus of this example, the above-described two kinds of penetrating substances were charged into the dissolution tank 46 so as to be supersaturated. Other configurations are the same as those in the seventh embodiment.

[Injection molding method and surface modification method]
Next, the molding method and surface modification method of this example will be described with reference to FIG. First, in the same manner as in Example 7, supercritical carbon dioxide in which two kinds of osmotic substances (first and second osmotic substances) are dissolved is introduced into the molten resin in the heating cylinder so that the two kinds of osmotic substances are surfaced. A plastic member impregnated with was prepared (steps S91 to S94 in FIG. 15). In this molding process, most of the penetrated metal complex is reduced to metal fine particles by the heat of the molten resin. Next, the plastic member was ultrasonically cleaned in pure water for 1 hour (step S95 in FIG. 15). In this cleaning treatment, among the penetrating substances penetrating the plastic member, ε-caprolactam (first penetrating substance) that is a water-soluble polymer is detached from the surface of the plastic member, and fine irregularities (micropores) are formed on the surface. ) Is formed. The metal fine particles, which are the other permeated substance, were hardly removed by this cleaning treatment, and kept penetrating into the surface of the plastic member. In this example, the surface modification of the plastic member was performed in this way.

[Method of forming plating film]
Next, electroless plating was applied to the plastic member produced by the surface modification method in the same manner as in Example 1 to form a plating film on the surface of the plastic member (Steps S96 and S97 in FIG. 15). As a result, like the plating films formed in Examples 1 to 4, the plating film formed in this example had no blistering, and the adhesion strength by the tape peeling test was good. In this example, the surface of the plastic member is not only formed with fine irregularities, but also impregnated with metal fine particles that serve as catalyst nuclei for the plating film. Due to the presence of this, it was possible to form a plating film with better adhesion.

  Further, when the surface roughness of the plating film formed in this example was measured with a stylus type surface roughness measuring device (manufactured by KLA-Tencor), the arithmetic average roughness (Ra) was 18.8 nm, The point average roughness (Rz) is 129.0 nm, which is an extremely small value compared to the plating film (Ra≈several to several tens of μm) formed by the conventional plating method (etching method), and good surface roughness. (Good smoothness) was obtained. That is, in this example, a plastic member having an electroless plating film having excellent adhesion and smoothness formed on the surface could be obtained.

  In Example 10, a plastic sheet having an osmotic substance on at least a surface thereof was produced by extrusion molding, and then a plastic member was produced by insert molding (in-mold) using the plastic sheet, and then the osmotic substance was removed. An example of a plastic member surface modification method and a method of forming a plating film (metal film) on the surface of the plastic member obtained by the surface modification method will be described.

  The resin material that can be used for the plastic sheet is arbitrary as long as it is a thermoplastic resin that can be extruded, but in this example, polycarbonate was used. Moreover, the material which permeate | transmits a plastic sheet | seat is also arbitrary, However In this Example, polyethyleneglycol was used for the osmosis | permeation substance. In this example, liquid high-pressure carbon dioxide was used as the pressurized fluid.

[Molding equipment]
First, the molding apparatus of this example used for producing a plastic sheet will be described. A schematic configuration diagram of the molding apparatus used in this example is shown in FIG. As shown in FIG. 16, the molding apparatus 600 used in this example mainly includes an extrusion molding machine unit 601, a carbon dioxide supply unit 602, and a carbon dioxide discharge unit 603.

  As shown in FIG. 16, the extrusion molding unit 601 mainly includes a plasticizing and melting cylinder 70 (hereinafter also referred to as a heating cylinder), a hopper 73 that supplies resin pellets into the heating cylinder 70, and a heating cylinder 70. A motor 72 for rotating the inner screw 71, a cooling jacket 77, a die 80 for extruding the molten resin while reducing the thickness of the molten resin and expanding the molten resin in a fan shape, and a cooling roll 81 are included. As the screw 71, a single screw having a vent structure portion 74 serving as a decompression portion was used.

  The structure and method of the extrusion die 80 are arbitrary and can be set as appropriate depending on the shape and use of the molded product to be produced. In this example, a T-die for film formation was used as the extrusion die 80. Further, in the molding apparatus 600 of this example, the plastic sheet 82 extruded from the T die 80 is wound up by the cooling roll 81 or the like. In this embodiment, the gap t at the die extrusion port of the T die 80 was set to 0.5 mm.

  Further, in the molding apparatus 600 of this example, as shown in FIG. 16, the carbon dioxide inlet 70 a is provided in the vicinity of the vent mechanism portion 74 of the single screw 71 where the molten resin is decompressed. Further, in the molding apparatus 600 of this example, as shown in FIG. 16, a monitor for measuring the resin internal pressure includes a connection part (monitor 76) between the heating cylinder 70 and the cooling jacket 77, and the inside of the cooling jacket 77 ( And a monitor 79).

  As shown in FIG. 16, the carbon dioxide supply unit 602 mainly includes a carbon dioxide cylinder 60, a syringe pump 62, a dissolution tank 61, a back pressure valve 63, a valve 64, a pressure gauge 66, and a configuration thereof. It is comprised from the piping 67 which connects an element. Further, as shown in FIG. 16, the downstream side (secondary side) of the valve 64 is connected to a carbon dioxide inlet 70a of the heating cylinder 70 via a pipe 67, and the molten resin inside the heating cylinder 70 is It is in circulation with the channel. In addition, the introduction | transduction location of a carbon dioxide is not limited to this, If it is the area | region from the screw 71 to the T-die 80, it can provide in arbitrary locations.

  Further, as shown in FIG. 16, the carbon dioxide discharge section 603 mainly includes an extraction container 83 for discharging carbon dioxide, a back pressure valve 84, a pressure gauge 85, and a pipe 86 connecting these components. Consists of Further, as shown in FIG. 16, the upstream side (primary side) of the back pressure valve 84 is connected to a carbon dioxide discharge port 77 a of the cooling jacket 77 via a pipe 86, and the molten resin inside the cooling jacket 77 is connected. It is in circulation with the channel.

  In the extrusion molding machine unit 601 of the present embodiment, each mechanism such as the screw 71, the heating cylinder 70, and the die 80 can have the same form as each mechanism of a known extrusion molding machine.

[Plastic sheet forming method]
Next, a method for forming a plastic sheet in the present embodiment will be described with reference to FIGS. First, a sufficient amount of pellets of resin material (polycarbonate) is supplied to the hopper 73 of the extrusion molding unit 601, and the screw 71 is rotated by the motor 72 to plasticize and melt the resin material. It was sent to the tip (step S101 in FIG. 20). At this time, the temperature of the heating cylinder 70 was adjusted to 280 ° C. by the band heater 75.

  Next, the osmotic substance was dissolved in the pressurized carbon dioxide by flowing the pressurized carbon dioxide (pressurized fluid) inside the dissolution tank 61 in which the osmotic substance was previously charged (step S102 in FIG. 20). Specifically, the osmotic material was dissolved in pressurized carbon dioxide as follows. First, the liquid carbon dioxide supplied from the carbon dioxide cylinder 60 was pressurized and adjusted with a syringe pump 62, and the pressure was adjusted so that the pressure gauge 66 was 15 MPa. The pressurized carbon dioxide was controlled to a temperature of 40 ° C. and flowed into the dissolution tank 61 charged so that the permeation substance was supersaturated, and the permeation substance was dissolved in the pressurized carbon dioxide.

  Next, the valve 64 is opened, and pressurized carbon dioxide in which the osmotic material is dissolved is introduced into the vent structure portion 74 of the heating cylinder 70 through the pipe 67 and the introduction port 70a, and the osmotic material is melted together with the pressurized carbon dioxide. The resin was brought into contact with the resin (step S103 in FIG. 20). At this time, the pressurized carbon dioxide in which the osmotic substance was dissolved at a constant flow rate was introduced while the flow rate of the pressurized carbon dioxide was controlled by the syringe pump 62 and the pressure of the pressurized carbon dioxide was controlled by the back pressure valve 63. At this time, the pressurized carbon dioxide and the penetrating substance (polyethylene glycol) injected into the molten resin of the vent structure portion 74 are kneaded into the resin by the rotation of the screw 71.

  Next, the molten resin was extruded from the heating cylinder 70 while adjusting the pressure of the molten resin kneaded with the pressurized carbon dioxide and the osmotic substance so as to increase to 20 MPa on the display of the internal pressure monitor 76.

  Next, the molten resin extruded from the heating cylinder 70 was passed through the cooling jacket 77. The cooling jacket 77 is cooled to 200 ° C. by temperature-controlled water flowing through a cooling water channel 78 provided inside the cooling jacket 77. Further, in the molding apparatus 600 of this example, as shown in FIG. 16, the cross-sectional area of the flow path of the molten resin inside the cooling jacket 77 is equal to the flow path of the molten resin at the connecting portion between the heating cylinder 70 and the cooling jacket 77. Since it is larger than the cross-sectional area, when the molten resin passes through the cooling jacket 77, the pressure is reduced simultaneously with the cooling. In this example, when the molten resin passed through the cooling jacket 77, the resin internal pressure monitor 79 in the decompression section showed 10 MPa.

  Next, the molten resin extruded from the cooling jacket 77 passes through the T die 80, and the resin 82 extruded from the T die 80 is wound up by a cooling roll 81 or the like and continuously formed into a film (sheet) ( Step S104 in FIG. 20). In this example, the resin 82 was thinned by a stretching apparatus (not shown) to produce a plastic sheet having a thickness of 0.1 mm. In this way, a plastic sheet in which polyethylene glycol was dispersed on the surface and inside was obtained.

[Insert molding]
Next, a method for producing a plastic member by insert (in-mold) molding using the plastic sheet produced by the extrusion molding will be described with reference to FIGS. The injection molding apparatus 900 used in the insert molding of this example has the same structure as the conventional one.

  First, as shown in FIG. 17, the plastic sheet 604 produced by the extrusion molding was held on the surface of the mold 90 on the cavity 97 side of the movable mold 91 (step S105 in FIG. 20). In this example, a movable mold 91 having a curved surface on the cavity 97 side is used, and a plastic sheet 604 is held on the curved surface of the mirror. The cavity 97 in the mold 90 is a space defined by the fixed mold 92 and the movable mold 91. In this example, the plastic sheet 604 is held by adsorbing the plastic sheet 604 to the surface of the movable mold 91 using the vacuum 93 circuit of the movable mold 91. At this time, as shown in FIG. 17, the plastic sheet 604 may not be completely in close contact with the surface of the movable mold 91, and the plastic sheet 604 is not between the surface of the movable mold 91 and the plastic sheet 604. There may be a gap in part. Further, in this embodiment, various known adhesive layers may be provided on the surface of the resin film 604 in order to improve the adhesion between the plastic sheet 604 and the resin material injected during the mold surface or insert molding. Good.

  Next, with the plastic sheet 604 held in the cavity 97 of the mold 90, the resin 96 plasticized and melted by the screw 95 of the injection molding apparatus 900 is injected and filled into the cavity 97 through the spool 95 of the injection molding apparatus 900. (Insert molding: step 106 in FIG. 20). At this time, as shown in FIG. 18, the plastic sheet 604 is brought into close contact with the mold surface by the injection resin (the gap between the plastic sheet 604 and the mold surface is eliminated), and the plastic sheet 604 has a predetermined shape ( Mirror shape). In this way, in this example, a plastic member in which the plastic sheet 604 and the molded product base 605 were integrated was obtained.

  At this time, the plastic sheet 604 may be plastically deformed or melted by the molten resin, but it is not affected at all by the quality of the metal film on the surface of the molded product. In this example, since the plastic sheet 604 having a certain degree of elasticity is insert-molded, a crack is generated in the film held inside the mold as in the case of insert-molding a metal film as in the past. There is no.

  In addition, in the manufacturing method of the plastic member of a present Example, arbitrary resin materials can be used for the filling resin material injection-molded at the time of insert (in-mold) molding. For example, synthetic fibers such as polyester, polypropylene, polymethyl methacrylate, polycarbonate, amorphous polyolefin, polyetherimide, polyethylene terephthalate, liquid crystal polymer, ABS resin, polyamideimide, polylactic acid and other biodegradable plastics, nylon resin, etc. These composite materials can be used. Further, a resin material in which various inorganic fillers such as glass fiber, carbon fiber, and nanocarbon are kneaded can also be used. The filling resin material may be the same as or different from the material of the plastic sheet, but is preferably the same material in order to improve the adhesion with the material of the plastic sheet. In this example, the same material as that of the plastic sheet, that is, polycarbonate was injection-filled by insert molding. However, a polycarbonate material containing 30% glass fiber and having a deflection temperature under load (ISO 75-2) of 148 ° C. was used.

  Moreover, in the plastic member manufacturing method of this example, the penetration amount and penetration depth of the osmotic material of the plastic member after insert molding can be controlled by controlling the film thickness of the plastic sheet impregnated with the osmotic material.

  The surface roughness of the plastic member obtained by the above-described insert molding in this example was measured with a stylus type surface roughness measuring device (manufactured by KLA-Tencor). The arithmetic average roughness (Ra) was 5 nm, and the ten-point average roughness (Rz) was 8 nm.

  Next, after the plastic member in which the plastic sheet 604 and the molded product base 605 are integrated is taken out from the injection molding machine 900, the plastic member is subjected to ultrasonic cleaning in an ethanol solvent for 30 minutes, and then the plastic sheet is obtained. The polyethylene glycol dispersed in the vicinity of the surface was removed (step S107 in FIG. 20). By this step, fine holes were formed at the locations where the polyethylene glycol was removed, and fine irregularities were formed on the surface of the plastic member. In this example, the surface modification of the plastic member was performed as described above.

  As described above, in the surface modification method for a plastic member of this embodiment, a low molecular component (in this example, polyethylene glycol) different from the material of the plastic sheet and the molded article substrate is removed from the plastic sheet by a solvent. Therefore, a resin molded product in which fine holes are formed at least on the surface of the molded product is obtained. The timing of the process of removing the low molecular components from the plastic sheet is arbitrary, and the removal process may be performed either before or after the insert molding. The size of the micropores can be controlled in a range from several nm order to micron order depending on the molecular weight of the low molecular component (penetrating substance) and the conditions for extracting and removing the low molecular component from the plastic sheet.

  The surface roughness of the plastic member having fine holes formed on the surface produced as described above was measured in the same manner as in Example 1. As a result, the arithmetic average roughness (Ra) is 15 nm, the ten-point average roughness (Rz) is 130 nm, and the surface roughness is increased before removing the penetrating substance, that is, compared to the plastic member after insert molding. It was. This indicates that the low-molecular component (polyethylene glycol) dispersed on the plastic sheet surface was removed and fine pores were formed. However, considering that the surface of the molded product is roughened by about several μm to several tens of μm in the chromic acid or permanganic acid etching process performed in the conventional plating process, the plastic member whose surface is modified in this embodiment It has been found that a good surface roughness (good smoothness) can be obtained as compared with a molded product roughened by a conventional etching treatment.

[Method of forming plating film]
Next, in this example, the plastic member from which polyethylene glycol was removed was subjected to electroless copper plating in the same manner as in Example 1 to form a plating film (step S108 in FIG. 20). In the step of applying the conditioner and the catalyst, ultrasonic vibration was applied in order to promote the immersion of the catalyst core and the plating film on the plastic sheet. As a result, like the plating films formed in Examples 1 to 4, the plating film formed in this example had no blistering, and the adhesion strength by the cross-hatch tape peeling test was also good.

  FIG. 19 shows an enlarged schematic cross-sectional view of the vicinity of the resin film of the plastic member having a plating film formed on the surface as described above. In the plastic member produced in this example, since the penetrating material (polyethylene glycol) dispersed in the vicinity of the surface of the plastic sheet is removed, the surface of the plastic sheet 604 formed on the molded article base material 605 is removed. As shown in FIG. 19, a partly fine hole 604a is formed. Then, by electroless plating, the catalyst core and the plating film 607 were immersed in the fine holes, and the anchor effect was obtained by the fine holes 604a on the surface of the plastic sheet 604, and the strong adhesion strength of the plating film was obtained. It is considered a thing. That is, in the plastic member on which the plating film of this example is formed, a strong anchor effect can be obtained with the surface kept as smooth as possible. Furthermore, the plastic member plating film forming method of this embodiment is easy even for resin materials that could not be sufficiently roughened by conventional etching, such as cycloolefin polymers, polycarbonate non-plating grades, and liquid crystal polymers. A plating film can be formed. In the plating film forming method of the present embodiment, a surfactant may be used so that the colloid of the palladium catalyst is easily adsorbed to the molded article substrate, as in the conventional method.

  In Example 11, an example of a method of modifying the surface of a plastic member without using a pressurized fluid and a method of forming a plating film on the surface of the plastic member will be described. In this example, polyethylene glycol (molecular weight 200), which is a water-soluble polymer, was used as the penetrating substance, and polycarbonate was used as the material for forming the plastic member. The procedure from the plastic member molding method and surface modification method to the plating film forming method of this example will be described below with reference to FIG.

[Molding method and surface modification method]
First, in this example, a polycarbonate (first plastic resin) was produced by kneading polycarbonate, which is a material for forming a plastic member, and polyethylene glycol, which is a penetrating substance, in a known extrusion molding machine. Specifically, the mixing ratio of polyethylene glycol to polycarbonate was set to 30%, and the mixture was supplied to an extruder. The resin was extruded from a die at the tip of the nozzle while melting and kneading with a screw. The obtained molded product was cooled with a cooling bath and granulated with a pelletizer. At this time, in order to make the kneading of the polycarbonate and polyethylene glycol uniform, modification such as modification of the terminal group with an additive to improve affinity may be performed. In this example, pellets (second plastic resin) made of polycarbonate not containing polyethylene glycol were produced by a known extrusion molding machine (step S111 in FIG. 21). In the present invention, the material for forming the plastic member may be any thermoplastic resin that can be extruded.

  Next, the plastic member was shape | molded by well-known sandwich molding using the two types of pellets obtained by the said method. The sandwich molding apparatus used in this example includes two heating cylinders and a die that circulates with the tip nozzles. The molten resin is fed from one heating cylinder (hereinafter also referred to as a first heating cylinder) into the mold. Is a known sandwich molding apparatus for injecting and molding molten resin from the other heating cylinder (hereinafter also referred to as a second heating cylinder). In the sandwich molding of this example, a plastic member was molded as follows.

  First, pellets of polycarbonate (first plastic resin) containing a penetrating substance were supplied into the first heating cylinder, and plasticized and melted (step S112 in FIG. 21). Further, a pellet of polycarbonate (second plastic resin) not containing an osmotic substance was supplied into the second heating cylinder and plasticized and melted (step S113 in FIG. 21). Next, a molten polycarbonate resin containing a penetrating substance was injected into the mold from the first heating cylinder (step S114 in FIG. 21). Next, the injection route of the molten resin was switched to the second heating cylinder, and the polycarbonate molten resin not containing the osmotic material was injected and filled into the mold from the second heating cylinder (step S115 in FIG. 21). As a result, a plastic member having a core layer made of polycarbonate containing no osmotic substance and a skin layer made of polycarbonate containing the osmotic substance formed on the core layer was obtained. In this example, a plastic member having a surface impregnated with a penetrating material was produced in this manner. Note that the plastic member molding method is not limited to sandwich molding, and insert molding, two-color molding, or the like may be used.

  The plastic member produced by the sandwich molding was subjected to ultrasonic cleaning in pure water for 1 hour (step S116 in FIG. 21). As a result, polyethylene glycol that had permeated the surface (skin layer) of the plastic member was released, and fine irregularities (micropores) were formed on the surface of the plastic member. That is, the shape of the surface of the plastic member was changed by the cleaning process. In this example, the surface modification of the plastic member was performed in this way.

[Method of forming plating film]
Next, electroless plating was applied to the plastic member produced by the surface modification method in the same manner as in Example 1 to form a plating film on the surface of the plastic member (steps S117 and S118 in FIG. 21). As a result, like the plating films formed in Examples 1 to 4, the plating film formed in this example had no blistering, and the adhesion strength by the tape peeling test was good.

  Further, when the surface roughness of the plating film formed in this example was measured with a stylus type surface roughness measuring apparatus (manufactured by KLA-Tencor), the arithmetic average roughness (Ra) was 16.2 nm, The point average roughness (Rz) is 125.8 nm, which is very small compared to the plating film (Ra≈several μm to several tens μm) formed on the plastic substrate by the conventional plating method (etching method). Thus, a good surface roughness (good smoothness) was obtained. That is, in this example, a plastic member having an electroless plating film having excellent adhesion and smoothness formed on the surface could be obtained.

  In Examples 1 to 5 and 7 to 10, the example in which the osmotic material is dissolved in the pressurized fluid in the dissolution tank has been described, but the present invention is not limited to this. For example, using a reservoir such as a cylinder filled with a pressurized fluid in which an osmotic substance is dissolved in advance, the pressurized fluid in which the osmotic substance is dissolved is directly supplied (introduced) from the reservoir to the plastic member (or molten resin). Also good.

  In Example 12, as in Example 10, a plastic sheet having an osmotic substance on at least the surface is produced, and a plastic member is produced by insert (in-mold) molding using the plastic sheet. An example of a method for modifying the surface of a plastic member for removing a substance and a method for forming a plating film (metal film) on the surface of a plastic member obtained by the surface modification method will be described. However, in this example, a method for producing a plastic sheet having a penetrating substance on the surface was used. In this example, supercritical carbon dioxide was used as an extraction solvent for the osmotic material when the osmotic material was removed.

[Production method of plastic sheet]
A method for producing the plastic sheet of this example will be described with reference to FIG. First, a film-like resin base material (resin film) containing no osmotic material was prepared (step S121 in FIG. 24). In this example, a polycarbonate film having a thickness of 100 μm was used as the resin film. As the resin film, any material can be used as long as it is a thermoplastic resin. In this example, since a plastic member is produced by insert molding as will be described later, it is desirable to use a material that melts or semi-melts during insert molding as the resin film. As explained in Example 10, even if the resin film is difficult to adhere to the mold surface before molding because of the mold surface shape being bent, etc., the melt filled with the resin film during insert molding By melting or semi-melting in contact with the resin, the mold surface shape can be traced completely with the resin film.

  Next, a mixed solution containing the same resin material as that of the resin film and a penetrating substance was prepared (step S122 in FIG. 24). In this example, carboxylate perfluoropolyether, which is a fluorine compound having a carboxyl group at the end, was used as the penetrating material, polycarbonate pellets were used as the resin material, and dichloromethane was used as the solvent of the mixed solution. . In this example, a mixed solution of polycarbonate and a penetrating substance was prepared by mixing 10 wt% of a penetrating substance (oily fluorine compound) with respect to the resin material in a solvent in which polycarbonate (resin material) was dissolved.

  Next, the mixed solution was applied on one side of the resin film by a casting method to form a resin thin film (resin film) having a penetrating substance dispersed therein on the resin film with a thickness of about 0.5 μm (FIG. 24). Middle step S123). In addition, the film thickness of the resin thin film in which the osmotic material is dispersed is desirably 0.01 to 10 μm. When the film thickness is less than 0.01 μm, the film thickness is too thin and it is difficult to obtain the anchor effect when forming the plating film. On the other hand, if the film thickness is thicker than 10 μm (if the film thickness is too thick), it takes time to extract the penetrating substance, which is uneconomical.

  In this example, a plastic sheet having a penetrating substance dispersed in the vicinity of the surface was produced as described above. As described above, when a plastic sheet is produced using the casting method, the resin thin film in which the osmotic substance is dispersed can be made thinner, and the penetration amount and distribution of the osmotic substance can be further adjusted. It becomes easy.

[Insert molding]
Next, a plastic member was molded by insert molding in the same manner as in Example 10 using a plastic sheet having a penetrating substance dispersed in the vicinity of the surface produced as described above. In this example, the same apparatus (mold and injection molding machine shown in FIG. 17) as in Example 10 was used for insert molding.

  In this example, first, a plastic sheet is inserted into the mold, and then a Teflon (registered trademark) block (not shown) having the same curved surface as the cavity surface shape of the fixed mold is used. The plastic sheet was pressed to hold the plastic sheet in close contact with the movable mold (step S124 in FIG. 24). At this time, the plastic sheet was held in the movable mold so that the resin thin film containing the penetrating substance formed on the resin film was opposed to the movable mold.

  Next, a molten resin of ABS-containing polycarbonate resin was injected and filled into the cavity to mold a plastic member (insert molding, step S125 in FIG. 24). Thereafter, in the same manner as in Example 10, the plastic member was taken out from the mold. In this example, in this way, a plastic member made of polycarbonate resin was obtained in which a plastic sheet in which a penetrating substance was dispersed in the vicinity of the surface and a molded base material made of ABS-containing polycarbonate resin were integrated.

[Penetration substance extraction method and extraction apparatus]
Next, the penetrating substance was extracted from the plastic member molded as described above. In this example, the penetrating substance is extracted after insert molding, but the penetrating substance dispersed on the surface of the plastic sheet may be removed by a solvent before insert molding. However, when a plastic sheet (or resin thin film) containing a penetrating material is formed of a thermoplastic resin, the plastic sheet is melted and thermally deformed by the molten resin injected and filled at the time of insert molding. If a plastic sheet from which the osmotic material is previously removed is used, the fine pores after the osmotic material is extracted may be deformed and lost during insert molding. Therefore, in the case where the plastic sheet containing the penetrating substance is formed of a thermoplastic resin as in this example, it is desirable to remove the penetrating substance after insert molding.

  Here, before describing the method for extracting the osmotic material, the osmotic material extraction device used in this example for extracting the osmotic material will be described. A schematic configuration of the osmotic substance extraction apparatus used in this example is shown in FIG.

  As shown in FIG. 25, the osmotic substance extraction device 700 is mainly composed of a liquid carbon dioxide cylinder 701, a buffer tank 702, a high-pressure pump 703, a high-pressure container 704 containing a plastic member, a circulation pump 705, It consists of two recovery tanks 706 and 707 for recovering the gas discharged from the high-pressure vessel 704 and the like, a recovery tank 708 for recovering the permeation material, and a pipe 715 that connects these components. As shown in FIG. 25, valves 709 to 711, a pressure reducing valve 712, and pressure gauges 713 and 714 for controlling the flow of the extraction solvent (pressurized carbon dioxide) in the extraction device 700 are provided in the pipe 715. It is provided in the position. Further, in the extraction apparatus 700 of this example, a pipe 715 is connected so that the extraction solvent circulates between the high-pressure vessel 704 and the circulation pump 705 (circulation system 716 in FIG. 25).

  In this example, the permeation substance dispersed inside the surface of the plastic member was extracted (removed) using the extraction device 700 shown in FIG. 25 as follows. First, a plurality of plastic members produced by the above-described molding method were placed in the high-pressure vessel 704.

  Next, the temperature inside the high-pressure vessel 704 was adjusted to 40 ° C. with temperature adjusting water (not shown). That is, in this example, the temperature when extracting the osmotic material was set to 40 ° C. In addition, when at least one of the forming material of the plastic member or the plastic sheet is an amorphous thermoplastic resin, as described later, when the osmotic substance is dissolved and extracted with pressurized carbon dioxide, the amorphous material is used. It is desirable to extract at a temperature that is at least 20 ° C. lower than the glass transition temperature of the thermoplastic resin. If the osmotic substance is extracted at a higher temperature, the amorphous thermoplastic resin swells due to the penetration of the pressurized carbon dioxide, so that the plastic member may be deformed. Further, when at least one of the plastic member or the plastic sheet forming material is a crystalline thermoplastic resin, the resin is not easily deformed by the penetration of pressurized carbon dioxide, but the penetrating substance at a temperature lower than the melting point of the resin. It is desirable to extract In any of the above cases, the extraction temperature of the osmotic material is desirably -10 ° C or higher. If the extraction temperature is lower than −10 ° C., carbon dioxide may solidify and become dry ice.

  In this embodiment, both the plastic member and the plastic sheet are formed of polycarbonate of an amorphous thermoplastic resin (both glass transition temperatures are about 145 ° C.), but a resin thin film in which a penetrating substance is dispersed is formed on the surface of the plastic member. Therefore, the glass transition temperature may be remarkably lowered on the surface of the plastic member. However, when the plastic member and plastic sheet produced in this example were actually exposed to pressurized carbon dioxide at 40 ° C. for a predetermined time, it was confirmed that the surfaces of the plastic member and plastic sheet were not deformed.

  Next, liquid carbon dioxide was supplied from the liquid carbon dioxide cylinder 701 to the buffer tank 702, and the liquid carbon dioxide was gasified in the buffer tank 702. Next, the carbon dioxide gasified by the high-pressure pump 703 was pressurized. At this time, the pressure of the pressurized carbon dioxide whose pressure was controlled by the pressure reducing valve 712 was increased to 15 MPa. Thereafter, the valve 710 was opened, and pressurized carbon dioxide was introduced into the entire high-pressure vessel 704 and the circulation system 716 that circulates with the high-pressure vessel 704. At this time, since the inside of the high-pressure vessel 704 is temperature-controlled at 40 ° C., the pressurized carbon dioxide introduced into the inside of the high-pressure vessel 704 becomes a supercritical state (supercritical carbon dioxide). In this example, the piping 715 and the circulation pump 705 in the circulation system 716 are set to room temperature without adjusting the temperature. In this room temperature portion, the introduced pressurized carbon dioxide is liquid pressurized carbon dioxide. It has become.

  Next, the circulation pump 705 was driven to circulate supercritical carbon dioxide and liquid pressurized carbon dioxide (hereinafter also simply referred to as pressurized carbon dioxide (extraction solvent)) in the circulation system 716. And this circulation state was maintained for 15 minutes. Through this process, the penetrating substance dispersed in the vicinity of the surface of the plastic member on the plastic sheet side was dissolved (extracted) by dissolving in pressurized carbon dioxide (step S126 in FIG. 24).

  After the pressurized carbon dioxide was circulated in the circulation system 716 for 15 minutes, the valve 711 was opened and the inside of the high-pressure vessel 704 was depressurized. The decompressed and gasified carbon dioxide was discharged into two recovery tanks 706 and 707. The carbon dioxide dissolved in the osmotic material discharged into the recovery tanks 706 and 707 is separated into the osmotic substance and carbon dioxide gas in the recovery tanks 706 and 707 by the principle of centrifugation. The carbon dioxide gas separated in the recovery tanks 706 and 707 is discharged to the outside through the pipe 715, and the permeating substance is recovered in the recovery tank 708 provided at the lower part of the recovery tanks 706 and 707. The permeation substance collected in the collection tank 708 is reused to prepare a mixed solution with the resin again. The osmotic substance extraction (removal) method using pressurized carbon dioxide according to this embodiment is an economical method because the osmotic substance can be easily recovered and reused.

  Next, the plastic member from which the osmotic material was extracted from the surface was taken out from the high pressure container. When the surface state of the plastic member taken out was observed by SEM, fine holes were formed on the surface of the plastic member on the plastic sheet side, and a plurality of holes were formed inside the surface of the plastic member on the plastic sheet side. It was confirmed that connected ant nest-like connection holes were formed. In addition, the average hole diameter of the connection hole was about 100 nm.

[Formation of plating film]
Next, a plating film was formed on the surface of the plastic member produced as described above on which the complicatedly shaped connection holes were formed. Specifically, as in Example 1, the plastic member is subjected to conditions (providing a surfactant), applying a catalyst, catalytic activity, and electroless plating to form a connecting hole for the plastic member. An electroless plating film having a thickness of 1 μm was formed on the surface (on the plastic sheet) (step S127 in FIG. 24). The formed plating film is glossy, and from this, it was found that the surface roughness of the plastic member on the side of the plastic sheet was good (small).

  A schematic cross-sectional view of a plastic member having a plating film formed on the surface produced in this example is shown in FIG. As shown in FIG. 26, the plastic member 720 of this example includes a resin film 722 of a plastic sheet, a resin thin film 723 from which a penetrating substance is removed, and a plating film 724 on a molding base 721 molded by insert molding. It has a laminated structure in this order. The resin film 722 and the molding substrate 721 are integrated by insert molding. A plating film enters and grows in a part of the connection hole 726 of the resin thin film 723. That is, the resin thin film 723 is provided with a plating permeation layer 725 in which a part of the plating film 724 has permeated. Although not shown in FIG. 26, in the plating process, Pd catalyst fine particles serving as catalyst nuclei of the plating film are dispersed inside the plating permeation layer 725 (connection holes), and the Pd catalyst fine particles are used as nuclei. Since the plating film grows, the plating film 724 formed in this example grows from the inside of the resin thin film 723. When the diameter of the connecting hole is fine, as shown in FIG. 26, the plating film does not penetrate the entire resin thin film 723, but the penetration thickness of the plating film can be adjusted by appropriately adjusting the diameter of the connecting hole. Can be adjusted.

  As described above, in the plastic member provided with the plating film produced in this example, the plating film is formed in a state where it partially penetrates into the plastic member, so that a physical anchor effect can be obtained, and more A plating film having excellent adhesion is formed. Moreover, since the hole (unevenness | corrugation) formed in the surface of a plastic member is also very small size, the plating film excellent in smoothness is obtained.

  An adhesion test was actually performed on the plastic member provided with the plating film produced in this example. Specifically, a 20-cycle heat cycle test was performed between a temperature of −40 ° C. and 85 ° C. for the plastic member including the plated film manufactured in this example. As a result, no film swelling occurred in the plating film. From this, in the plastic member of the present Example, it turned out that the plating film is closely_contact | adhered to the resin surface by the strong anchor effect.

  In this example, an oily fluorine compound is used as the osmotic substance, but any material that dissolves in the extraction solvent can be used as the osmotic substance. In particular, as in this example, when pressurized carbon dioxide such as supercritical carbon dioxide or liquid carbon dioxide, which has high permeability to plastic members and excellent extraction ability, is used as the extraction solvent, Various surfactants that dissolve in pressurized carbon dioxide, fluorine-based low molecular weight polymers, inorganic fillers such as calcium carbonate that dissolve in acid, and the like can be used.

  When pressurized carbon dioxide is used as the extraction solvent, an organic substance that dissolves in pressurized carbon dioxide can be used as the osmotic substance. Examples of such organic substances include polyethylene oxide (PEO) -polypropylene oxide (PPO) block copolymer, PEO-polybutylene oxide (PBO) block copolymer, octaethylene glycol monododecyl ether, pentaethylene glycol n-octyl. Ether or the like can be used.

Furthermore, when pressurized carbon dioxide is used as the extraction solvent, a surfactant containing fluorine having high solubility in pressurized carbon dioxide may be used as the penetrating substance. Examples of the fluorine-containing surfactant include various fluorinated polyalkylene glycols and carboxylate perfluoropolyethers (chemical structural formula: F- (CF ₂ CF (CF ₃ ) O) n-CF ₂ CF ₂ COOH ( Product name Kritox), perfluoropolyether carboxylic acid ammonium salt ((chemical structural formula: F- (CF (CF ₃ ) CF ₂ O) n-CF (CF ₃ ) COO-NH ₄ + (Daikin Chemical Industries, Ltd.) Ltd. C2404 ammonium salts), can be used various surfactants having a perfluoro alkyl analogs, perfluoropolyether (PFPE) group Surufakohaku ester salt (AOT). Further, the fluorinated polymer (hexafluoropropylene epoxide, Dupon Kritox GPL207 manufactured by the company It may be used and silicone oil as an osmotic agent.

  In Example 12, metal fine particles serving as catalyst nuclei of the plating film were dispersed in the plastic sheet (resin thin film) at the stage of the plating treatment, but the metal fine particles may be dispersed in advance in the plastic sheet. . One example will be described in Example 13. Specifically, in this example, when a plastic sheet is produced, a palladium plating catalyst core is dispersed under the resin thin film (first resin thin film) in which the penetrating material is dispersed (connection holes are formed). A resin thin film (second thin film) was provided. Hereinafter, a series of steps from the production of the plastic member to the formation of the plating film in this example will be described with reference to FIG.

  First, similarly to Example 12, a polycarbonate resin film having a thickness of 100 μm was prepared (step S131 in FIG. 27). Next, a mixed solution (first mixed solution) containing the same resin material as the resin film and the metal complex was prepared (step S132 in FIG. 27). In this example, a hexafluoroacetylacetonato palladium (II) complex was used as the metal complex, and the resin material and the solvent of the mixed solution were the same as in Example 12. In this example, a 1 wt% metal complex was mixed with the resin material in a solvent in which polycarbonate (resin material) was dissolved to prepare a first mixed solution of polycarbonate and metal complex. In this example, Pd is used as the metal element of the metal fine particles serving as the catalyst core for plating, but platinum, nickel, copper, or the like can be used in other cases.

  Next, the first mixed solution was applied on one side of the resin film by a casting method to form a first resin thin film (first resin film) having a metal complex dispersed therein with a thickness of about 0.5 μm ( Step S133 in FIG. 27).

  Next, in the same manner as in Example 12, a mixed solution (second mixed solution) containing the same resin material as the resin film and a penetrating substance was prepared (step S134 in FIG. 27). In this example, the permeation substance, the resin material, and the solvent of the mixed solution were the same as those in Example 12. Next, the second mixed solution was applied onto the first resin thin film by a casting method to form a second resin thin film (second resin film) having a penetrating substance dispersed therein with a thickness of about 1 μm (in FIG. 27). Step S135).

  Next, the plastic sheet having the first and second resin thin films formed on the resin film was heated in a temperature environment of 100 ° C. for 5 hours. By this treatment, a part of the metal complex distributed in the first resin thin film was thermally decomposed, reduced, and immobilized (a part of the metal complex was transformed into metal fine particles). In this example, a plastic sheet having a penetrating substance and fine metal particles dispersed therein was produced in this manner.

  Next, the plastic sheet obtained as described above was held in a mold of an injection molding machine in the same manner as in Example 12 to perform insert molding (steps S136 and S137 in FIG. 27). . In this example, the same resin as that used in Example 12 was used as the resin (molding base material) injected and filled into the mold by insert molding. In this example, the plastic member was molded in this way.

  Next, with respect to the plastic member produced as described above, the osmotic substance was subjected to pressurized carbon dioxide (solvent) in the same manner as in Example 12 using the extraction device (FIG. 25) used in Example 12. ) To extract from the plastic member (step S138 in FIG. 27). By this treatment, connection holes were formed in the first resin thin film. Next, electroless plating of nickel phosphorus plating was performed on the plastic member, and a plating film was formed on the surface of the plastic member on the plastic sheet side. At this time, the plating solution penetrates into the first resin thin film through the connection hole in the first resin thin film and reaches the second resin thin film. Then, the plating solution contacts the Pd metal fine particles dispersed in the second resin thin film, and the plating film grows with the metal fine particles as nuclei. Therefore, in the plating film forming method of this example, since the plating film grows from the inside of the plastic sheet, more specifically, from the vicinity of the interface between the first and second resin thin films, a larger anchor effect is obtained. Thus, the adhesion between the plastic member and the plating film is further increased. In this example, a plastic member having a plating film formed on the surface was thus obtained.

  In the plating film method of this example, the catalyst application step after the insert molding is unnecessary as in the twelfth embodiment. Therefore, in the method of this example, since the plating film can be formed immediately after the first resin thin film having the connecting hole is formed (after the permeation substance is extracted), the process can be simplified and the mass productivity is improved.

  In addition, the concentration of catalyst nuclei on the plastic member produced by the manufacturing method of this example (in the plastic sheet, the outermost surface of the plastic member on the plastic sheet side (the outermost surface of the first resin thin film in which the connecting holes are formed)) Since a sufficient amount of catalyst nuclei are dispersed inside, the plating film is difficult to grow on the outermost surface of the plastic member on the plastic sheet side when plating is performed. The film can be reliably grown from the inside of the plastic member, and the manufacturing method of this example can reliably form an inclined layer (plating film permeation layer) in which a resin and a plated metal film are mixed. Furthermore, in this example of the plastic member manufacturing method, the plating reaction takes place at a low temperature of about room temperature. Even when Cu plating is applied, the concentration of catalyst nuclei on the outermost surface of the plastic member on the plastic sheet side is low, so that plating reaction does not occur on the surface and a plating film can be grown from inside the plastic member. it can.

  FIG. 28 shows a schematic cross-sectional view of a plastic member having a plating film formed on the surface produced in this example. As shown in FIG. 28, the plastic member 730 of this example includes a plastic sheet resin film 732, a second resin thin film 733 in which metal fine particles 736 are dispersed, and a penetrating substance on a molding substrate 731 molded by insert molding. The first resin thin film 734 having the connection holes 737 formed therein and the plating film 735 are stacked in this order. The resin film 732 and the molding substrate 731 are integrated by insert molding. The plating film 735 grows from the metal fine particles 736 existing in the vicinity of the surface of the second resin thin film 733 on the first resin thin film 734 side through the connection hole 736 of the first resin thin film 734, and The part has penetrated into the plastic member. Therefore, in this example, the thickness of the plating film permeation layer is substantially the same as the thickness of the first resin thin film 734.

  When the reliability of the plating film was evaluated on the plastic member provided with the plating film produced as described above in the same manner as in Example 12, problems such as swelling of the plating film did not occur.

  In Example 13, the step of extracting the penetrating substance and the step of penetrating the plating solution into the plastic member were performed in separate steps, but these steps may be performed simultaneously. In Example 14, an example will be described.

  In this example, first, in the same manner as in Example 13, a plastic sheet in which a second resin film in which metal fine particles were dispersed and a first resin thin film in which a penetrating material was dispersed was formed on a resin film. Next, the plastic sheet was held in the mold in the same manner as in Example 12 to perform insert molding, and the plastic sheet and the molding substrate were integrated to produce a plastic member.

  Next, using the extraction apparatus (FIG. 25) used in Example 12, the steps of extracting the penetrating material and forming the plating film were performed as follows. First, the plastic member produced as described above was mounted in a high-pressure vessel 704 adjusted to 40 ° C. At the same time, a nickel phosphorus plating solution mixed with methanol (alcohol) at a ratio of 40 vol% was introduced into the high-pressure vessel 704, and the plastic member was immersed in the plating solution. Next, in the same manner as in Example 12, pressurized carbon dioxide having a pressure of 10 MPa was introduced into the high-pressure vessel 704 and retained. By this step, the plating solution penetrates into the plastic member together with the pressurized carbon dioxide. At this time, the mixed solution of the plating solution and the pressurized carbon dioxide penetrates into the plastic member while extracting the penetrating substance in the first resin thin film. In addition, since the reaction temperature of the plating solution used in this example is 65 ° C. or higher, the plating reaction does not occur in the above process in the high-pressure vessel 704 adjusted to 40 ° C.

  Next, the temperature of the high-pressure vessel 704 was raised to 80 ° C. (temperature at which the plating reaction occurs) with temperature control water (not shown). As a result, the pressure in the high-pressure vessel 704 increased to 15 MPa. By this step, the plating solution was brought into contact with the Pd-derived metal fine particles dispersed in the second resin thin film, and a plating film was grown from the inside of the plastic member. In this example, the plating film was thus formed on the surface of the plastic member on the plastic sheet side. As a result, also in this example, a plastic member having the same structure as that of Example 12 (FIG. 28) is obtained, and the plating film is formed from the inside of the plastic member. A plating film grew from the vicinity, and a plating film having excellent adhesion could be formed.

  Also for the plastic member provided with the plated film produced in this example, as in Example 12, when the reliability of the plated film was evaluated, there was no problem such as swelling of the plated film.

  Note that when pressurized carbon dioxide in a supercritical state or the like is mixed with the plating solution as in this example, the surface tension of the plating solution is lowered, and the plating solution is likely to penetrate into the plastic member. Therefore, the plating solution can easily penetrate into the first resin thin film in which the fine connection holes are formed, and the plating solution can easily reach the second resin thin film in which the metal catalyst fine particles are dispersed. As a result, since the plating film grows quickly from the second resin thin film, the plating rate increases and the efficiency is high.

  Further, as in this example, when pressurized carbon dioxide in a supercritical state or the like is mixed with the plating solution, the pH (hydrogen ion index) of the plating solution is lowered by the carbon dioxide, so that the plating solution is an alkaline plating bath. May neutralize the plating solution and prevent the plating reaction from occurring. Therefore, when pressurized carbon dioxide is mixed in the plating solution as in this example, it is desirable to use an acidic plating bath such as palladium or nickel phosphorus as the plating solution.

  When pressurized carbon dioxide in a supercritical state or the like is mixed with the plating solution, it is desirable to add an alcohol component to the plating solution as in this example. In this case, the alcohol serves as a surfactant to increase the mixing ability of the plating solution and carbon dioxide, and to reduce the surface tension of the plating solution to facilitate penetration of the plating solution into the resin.

  In Examples 12 to 14, the example in which the penetrating substance was extracted after the insert molding to form fine connection holes on the surface of the plastic member was described, but in Example 15, the penetrating substance was extracted before the insert molding. An example of forming fine connection holes will be described. When the material for forming the resin thin film in which the osmotic material is dispersed is formed of a material that is not easily thermally deformed, the osmotic material can be extracted before insert molding.

  In Examples 13 and 14, the resin thin film in which the penetrating substance is dispersed and the resin thin film in which the metal fine particles are dispersed are separately formed. In this example, the penetrating substance and the metal fine particles are dispersed in one resin thin film. An example will be described.

  In this example, a two-component mixed curing type epoxy thermosetting resin, which is a high heat resistant resin material, was used as a material for forming a resin thin film in which a penetrating substance and fine metal particles are dispersed. As the penetrating substance, liquid polyethylene glycol having an average molecular weight of 200 was used. In addition, as in Example 13, a hexafluoroacetylacetonato palladium (II) complex was used as the metal complex to be mixed with the resin material and the penetrating substance. Below, the manufacturing method of the plastic member of this example is demonstrated, referring FIG.

  First, a long polycarbonate resin film having a thickness of 100 μm was prepared (step S141 in FIG. 29). Next, a mixed solution containing a penetrating substance, a metal complex, and an epoxy thermosetting resin was prepared (step S142 in FIG. 29). Specifically, polyethylene glycol (penetrating substance) is mixed at a rate of 30 wt% with respect to the epoxy resin adhesive, and an epoxy resin adhesive mixed with a palladium metal complex at a rate of 1 wt% is N as the solvent. -It was dissolved in a mixed solvent of methyl-2-pyrrolidone and toluene to prepare a mixed solution containing an osmotic substance, a metal complex and an epoxy thermosetting resin.

  Next, the mixed solution was applied onto a resin film by a casting method to form a resin thin film having a penetrating substance and a metal complex dispersed therein with a thickness of 1 μm (step S143 in FIG. 29). Next, the resin film was heated at a temperature of 120 ° C. for 10 hours to thermally cure the epoxy resin adhesive. Further, by this heat treatment, the metal complex was thermally decomposed and reduced, and the catalyst core for plating was immobilized. In this manner, a long plastic sheet in which the penetrating substance and the metal fine particles were dispersed inside the highly heat-resistant resin thin film was produced.

  Next, the long plastic sheet was wound around an aluminum mesh sheet as a separator, and charged into the high-pressure vessel 704 of the extraction apparatus 700 shown in FIG. Next, in the same manner as in Examples 12 and 13, pressurized carbon dioxide was introduced into the high-pressure vessel 704 to extract the permeating substance (step S144 in FIG. 29). By this step, a connection hole was formed over the thickness of about 1 μm of the resin thin film made of epoxy resin formed on one surface of the plastic sheet.

  Next, the plastic sheet with the connection hole formed on the surface was held in the mold in the same manner as in Example 12, and insert molding (injection filling with polycarbonate resin) was performed to mold the plastic member (in FIG. 29). Steps S145 and S146). At this time, in this example, since the resin thin film of the plastic sheet is formed of a high heat resistant material, the fine connecting holes inside the resin thin film are thermally deformed or blocked by the temperature and pressure of the molten resin injected and filled. There is nothing to do. In this example, as described above, a plastic member having a fine connection hole formed in the vicinity of the surface was produced.

  Next, an electroless plating film was formed on the surface of the plastic member manufactured as described above on the side of the plastic sheet using pressurized carbon dioxide in the same manner as in Example 14 (step S147 in FIG. 29). . In this embodiment, since the osmotic substance is extracted before insert molding, the osmotic substance extraction step is not included when the plating film is formed. In this example, a plastic member provided with a plating film was obtained as described above.

  When the adhesion of the plating film was examined for the plastic member produced in this example, good adhesion was obtained. That is, as in this example, when the resin thin film in which the connection hole is formed is formed of a high heat resistant material, the connection hole is not formed during insert molding even if the penetrating material is extracted before the insert molding to form the connection hole. It was found that an anchoring effect for obtaining adhesion between the plastic member and the plating film is obtained, which is difficult to deform.

  Further, as in this example, the method of extracting the penetrating substance before insert molding can also provide the following advantages. As in Examples 12 to 13, when the penetrating substance is removed using pressurized carbon dioxide in a supercritical state after insert molding, the molded product itself must be inserted into a high-pressure vessel, so that the treatment is performed at a time. There is a limit to the number of moldings that can be made. Further, when processing a large molded product, the processing becomes difficult, and it is necessary to increase the internal volume of the high-pressure vessel, which is expensive. On the other hand, as in this example, when the penetrating material is removed in the form of a film (in the state of a plastic sheet) before insert molding, the number of plastic sheets that can be processed at a time increases. The above problem is solved. In particular, as in this example, when pressurized carbon dioxide in a supercritical state or the like is used as a solvent for removing osmotic substances, the pressurized carbon dioxide is excellent in diffusibility and permeability. Even when the plastic sheet is rolled up, it can be processed all at once, and large area processing is possible. Therefore, a process excellent in throughput and cost can be provided.

  In this example, an epoxy thermosetting resin is used as the material for forming the resin thin film in which the connection hole is formed. However, any material can be used as long as the material does not undergo significant plastic deformation due to heat and load applied during insert molding. It is desirable to have a heat resistance of at least 100 ° C. or higher, desirably 150 ° C. or higher, more desirably 200 ° C. or higher (weighted heat distortion temperature). For example, a thermosetting resin such as epoxy, a thermosetting resin such as polyimide or silicone, or a thermoplastic resin such as polyetherimide, polyamideimide, polyphenylene sulfide, polybutylene terephthalate, or polyphthalamide can be used.

  As a material for forming a resin film of a plastic sheet, in order to improve adhesion with an injection molding molten resin made of a thermoplastic resin and trace a complicated mold surface shape, A material in which the contact surface or the resin film itself is melted or semi-melted at the time of insert molding is preferable. Specifically, it is desirable to use a thermoplastic resin. In addition, even if the resin thin film formed on a resin film is a film | membrane which is hard to heat-deform, a metal mold | die shape can be traced at the time of shaping | molding by thinning a resin thin film.

  Moreover, in this example, although the high heat resistant resin thin film which has a connection hole was formed in the one side surface of a resin film, you may form a high heat resistant resin thin film on both surfaces of a resin film. By providing a resin thin film with a connection hole that is not easily plastically deformed even when exposed to high temperature and pressure on the adhesive surface of the resin film with the insert molding resin material, the connection hole is formed inside the high heat resistant resin thin film during insert molding. The molten resin is filled through the resin, and adhesion between the resin film and the molding substrate can be ensured.

  In the surface modification method of the present invention, fine unevenness of sub-micron to nano order can be formed on the surface of a plastic member using a pressurized fluid for various types of plastics. Therefore, for example, when the surface modification method of the present invention is used as a pretreatment process for electroless plating, it is suitable as a pretreatment process for electroless plating at low cost.

  In the method for forming a metal film of the present invention, a metal film having excellent smoothness and adhesion can be formed on the surface of various types of plastic members without using a harmful etchant as in the conventional plating method. . Therefore, the metal film formation method of the present invention can be applied to all fields and is suitable as a low-cost and clean metal film formation method. Moreover, the method for forming a metal film of the present invention can be easily applied to a molded product having a complicated shape with a large area.

  Moreover, since the fine hole can be formed in the surface of a plastic member in the surface modification method and the manufacturing method of a plastic member of this invention, it can be used for the following uses. For example, when a biodegradable plastic such as polylactic acid is used as the material of the plastic member, it can be applied as a regenerative medical device for culturing cells in micropores. Further, when the size of the micropores is about 100 nm or less, which is sufficiently smaller than the wavelength of visible light, the refractive index of the surface of the molded product can be reduced by increasing the porosity. Furthermore, the surface reflectance can be suppressed by inclining the porosity distribution from the surface to the inside of the plastic member. In this case, it is necessary to increase the porosity of the surface as compared with the inside of the plastic member. However, in the method for removing penetrants of the surface modification method of the present invention, more low molecular components are extracted (removed) as they are closer to the surface. Therefore, the inclination of the porosity distribution from the surface to the inside of the plastic member can be controlled more easily.

FIG. 1 is a schematic configuration diagram of a surface modification apparatus used in Example 1. FIG. 2 is an AFM observation image of the surface of the molded plastic member, FIG. 2 (a) is an AFM observation image before removing the osmotic material, and FIG. 2 (b) is an AFM observation image after removing the osmotic material. is there. FIG. 3 is a flowchart for explaining the procedure of the surface modification method and the metal film formation method according to the first embodiment. FIG. 4 is a schematic configuration diagram of the surface modification apparatus used in Example 5. FIG. 5 is an enlarged cross-sectional view of a region surrounded by a broken line A in FIG. FIG. 6 is a flowchart for explaining the procedure of the surface modification method and the metal film formation method according to the fifth embodiment. FIG. 7 is a schematic configuration diagram of the surface modification apparatus used in Example 6. FIG. 8 is an enlarged sectional view of a region surrounded by a broken line A in FIG. FIG. 9 is an enlarged cross-sectional view of a region surrounded by a broken line A in FIG. FIG. 10 is an enlarged cross-sectional view of a region surrounded by a broken line A in FIG. FIG. 11 is a flowchart for explaining the procedure of the surface modification method and the metal film formation method according to the sixth embodiment. FIG. 12 is a schematic configuration diagram of the molding apparatus used in Example 7. FIG. 13 is a view showing a state at the time of injection filling of a molten resin, FIG. 13 (a) is a view showing a state at the time of initial filling, and FIG. 13 (b) is a state at the time of filling completion. FIG. FIG. 14 is a flowchart for explaining the procedure of the surface modification method and the metal film formation method of Example 7. FIG. 15 is a flowchart for explaining the procedure of the surface modification method and the metal film formation method of Example 9. FIG. 16 is a schematic configuration diagram of the molding apparatus used in Example 10. FIG. 17 is a view for explaining a method of insert molding, and shows a state before injecting molten resin. FIG. 18 is a view for explaining a method of insert molding, and is a view showing a state when the molten resin is injected and filled. FIG. 19 is a schematic cross-sectional view of the plastic molded product produced in Example 10. FIG. 20 is a flowchart for explaining the procedure of the surface modification method and the metal film formation method of Example 10. FIG. 21 is a flowchart for explaining the procedure of the surface modification method and the metal film formation method of Example 11. FIG. 22 is a flowchart for explaining the procedure of the surface modification method of the present invention. FIG. 23 is a flowchart for explaining the procedure of the metal film forming method of the present invention. FIG. 24 is a flowchart for explaining the procedure of the surface modification method and the metal film formation method of Example 12. FIG. 25 is a schematic configuration diagram of the extraction device used in Example 12. FIG. 26 is a schematic cross-sectional view of the plastic member produced in Example 12. FIG. 27 is a flowchart for explaining the procedure of the surface modification method and the metal film formation method of Example 13. FIG. 28 is a schematic cross-sectional view of a plastic member manufactured in Example 13. FIG. 29 is a flowchart for explaining the procedure of the surface modification method and metal film formation method of Example 15.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Carbon dioxide cylinder 2 Syringe pump 3 Dissolution tank 4 High pressure vessel 4 'Die 5 Collection tank 100, 200, 300 Reformer 101, 201 Plastic member 202, 302 Recess 203, 303 Through hole 305 Penetration substance 400, 900 Injection molding Apparatus 600 Extrusion molding apparatus 604 Plastic sheet 604a Fine hole 605 Molded article base material 606 Plating catalyst core 607 Metal film

Claims (24)

A method of forming a metal film on the surface of a plastic member,
Providing a plastic member impregnated on the surface with a penetrating substance;
Removing the penetrating substance from the surface of the plastic member by bringing the solvent into contact with the plastic member and dissolving the penetrating substance in the solvent;
Forming a metal film on the surface of the plastic member from which the penetrating material has been removed. Forming a metal film on the surface of the plastic member from which the penetrating material has been removed,
Providing a plating catalyst nucleus on the surface of the plastic member from which the penetrating material has been removed;
The method for forming a metal film according to claim 1, further comprising: forming a metal film on a surface of the plastic member provided with the plating catalyst nucleus by an electroless plating method. Preparing a plastic member impregnated on the surface with the osmotic material,
Dissolving the penetrant in a pressurized fluid;
The method for forming a metal film according to claim 1, further comprising bringing the pressurized fluid into contact with a plastic member and allowing the penetrating substance to penetrate into the surface of the plastic member. Preparing a plastic member impregnated on the surface with the osmotic material,
Applying a solution in which the penetrant is dissolved to the surface of the plastic member;
The metal film according to claim 1, further comprising contacting a pressurized fluid with the plastic member to which the osmotic material is applied to infiltrate the osmotic material into the surface of the plastic member. Method. The plastic member has a recess, and when the penetrating substance permeates the inside of the surface of the plastic member, the concave portion defines the surface of the plastic member with the pressurized fluid in contact with the plastic member. 5. The osmotic substance is infiltrated into the surface of the plastic member defining the recessed portion by blocking the formed opening and retaining the pressurized fluid in the recessed portion. Method for forming a metal film. The method for forming a metal film is a method for forming a metal film using an injection molding machine provided with a mold and a heating cylinder for injecting a molten resin of a plastic member into the mold,
Preparing a plastic member impregnated on the surface with the osmotic material,
Bringing the pressurized fluid in which the osmotic material is dissolved into contact with the flow front portion of the molten resin in the injection molding machine to infiltrate the osmotic material into the molten resin;
The method for forming a metal film according to claim 1, comprising injection-filling the molten resin into the mold and forming the mold. A plastic member in which a concave / convex pattern is formed on the cavity side surface of the mold, the molten resin is injected and filled into the cavity of the mold, has a concave portion on the surface, and a penetrating substance penetrates the surface of the concave portion When the osmotic substance is dissolved and removed from the surface of the plastic member with a solvent, the osmotic substance that has permeated the concave part is removed by bringing the solvent into contact with only the surface of the concave part. The method for forming a metal film according to claim 6. The metal film forming method is a metal film forming method using an extrusion molding machine,
Preparing a plastic member impregnated on the surface with the osmotic material,
Bringing the pressurized fluid in which the osmotic material is dissolved into contact with the molten resin of the plastic member in the extrusion molding machine to infiltrate the osmotic material into the molten resin;
3. The method of forming a metal film according to claim 1, further comprising extruding the molten resin. The pressure of the said pressurized fluid is 5-25 Mpa, The formation method of the metal film as described in any one of Claims 3-8 characterized by the above-mentioned. The method for forming a metal film according to any one of claims 3 to 9, wherein the pressurized fluid is carbon dioxide. A plastic member impregnated on the surface with the penetrating material is produced using an injection molding machine equipped with a mold,
Preparing a plastic member impregnated on the surface with the osmotic material,
Preparing a plastic sheet impregnated on the surface with the penetrant;
Holding the plastic sheet in the mold of the injection molding machine;
Forming the plastic member by injection-filling the molten resin in the injection molding machine into the mold holding the plastic sheet, and forming the metal film according to 1 or 2 Method. The plastic sheet is produced using an extrusion machine,
Preparing a plastic sheet impregnated on the surface with the osmotic material,
Contacting the pressurized fluid in which the osmotic substance is dissolved with the molten resin in the extrusion molding machine to infiltrate the osmotic substance into the molten resin;
The method for forming a metal film according to claim 11, comprising extruding the molten resin to form the plastic sheet. Preparing a plastic sheet impregnated on the surface with the osmotic material,
Preparing a plastic film;
Preparing a mixed solution comprising the penetrant and plastic resin;
The metal film formation according to claim 11, further comprising: applying the mixed solution on the plastic film to form a resin film in which the osmotic material is dispersed on the plastic film. Method. A plastic member impregnated on the surface with the penetrating material is produced using an injection molding machine equipped with a mold,
Preparing a plastic member impregnated on the surface with the osmotic material,
Preparing a plastic film;
Preparing a first mixed solution containing metal fine particles and a first plastic resin;
Preparing a second mixed solution comprising the penetrant and the second plastic resin;
Applying the first mixed solution on the plastic film to form a first resin film in which the metal fine particles are dispersed on the plastic film;
Applying a second mixed solution on the first resin film to form a second resin film in which the osmotic material is dispersed on the first resin film;
Holding the plastic film on which the first and second resin films are formed in a mold of the injection molding machine;
2. The method of forming a metal film according to 1, wherein the plastic member is formed by injecting and filling a molten resin in the injection molding machine into the mold in which the plastic film is held. Preparing a plastic member impregnated on the surface with the osmotic material,
Preparing a plastic film;
Preparing a mixed solution containing the osmotic material, fine metal particles and plastic resin;
Applying the mixed solution on the plastic film to form a resin film in which the osmotic substance and metal fine particles are dispersed on the plastic film,
The metal film formation method is a metal film formation method using an injection molding machine equipped with a mold, and the metal film formation method further removes the penetrating substance,
Holding the plastic film on which the resin film is formed in a mold of the injection molding machine;
2. The method of forming a metal film according to claim 1, further comprising molding the plastic member by injecting and filling a molten resin in the injection molding machine into the mold in which the plastic film is held. The metal film forming method is a metal film forming method using an injection molding machine including a mold and a first and second heating cylinder for injecting a molten resin of a plastic member into the mold,
Preparing a plastic member impregnated on the surface with the osmotic material,
Providing a first plastic resin containing the osmotic material and a second plastic resin not containing the osmotic material;
Plasticizing and melting the first plastic resin in the first heating cylinder;
Plasticizing and melting the second plastic resin in the second heating cylinder;
Injecting the molten first plastic resin into the mold,
3. The metal film according to claim 1, further comprising: injecting and filling a molten second plastic resin into the mold after the first plastic resin is injected, and molding the plastic member. 4. Forming method. The said plastic member is formed from any one of a thermoplastic resin, a thermosetting resin, and a photocurable resin, The formation method of the metal film as described in any one of Claims 1-16 characterized by the above-mentioned. . The method for forming a metal film according to claim 1, wherein the penetrating substance is a water-soluble polymer or a water-soluble monomer. The method for forming a metal film according to any one of claims 1 to 18, wherein the penetrating substance is polyethylene glycol. The molecular weight of the said osmotic material is 50-2000, The formation method of the metal film as described in any one of Claims 1-19 characterized by the above-mentioned. 19. The osmotic material includes a first osmotic material and a second osmotic material, and the first osmotic material is removed when removing the osmotic material from the surface of the plastic member. The method for forming a metal film according to any one of the above. The method of forming a metal film according to claim 21, wherein the first penetrating substance is a water-soluble polymer or a water-soluble monomer. The method for forming a metal film according to claim 21 or 22, wherein the molecular weight of the first osmotic material is 50 to 2,000. A method of manufacturing a plastic member,
Providing a plastic member impregnated on the surface with a penetrating substance;
A manufacturing method comprising: bringing a solvent into contact with the plastic member; dissolving the osmotic material in the solvent; and removing the osmotic material from the surface of the plastic member.

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