JP2007131864A - Polymer member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polymer member having the surface selectively (partially) modified with a fine pattern. <P>SOLUTION: The polymer member has a polymer substrate having grooves in a prescribed pattern formed on the surface, and an organic material infiltrating into the inside of the surface of the groove. As a result, the polymer member having the surface modified with the fine pattern can be obtained. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a polymer member, and more particularly to a surface-modified polymer member.

  In recent years, various processes have been proposed in which a supercritical fluid that has permeability as a gas and at the same time functions as a solvent such as a liquid is used for molding a polymer. For example, the supercritical fluid acts as a plasticizer by penetrating into the thermoplastic resin and can reduce the viscosity of the polymer. Therefore, the fluidity of the polymer at the time of injection molding is utilized by utilizing the action of this supercritical fluid. And a method for improving transferability has been proposed (see, for example, Patent Document 1).

  In addition, various methods for enhancing the function such as improving the wettability of the polymer surface by utilizing the function of the supercritical fluid as a solvent have been proposed (see, for example, Patent Documents 2 and 3). Patent Document 2 discloses that a fiber surface can be hydrophilized by dissolving a polyalkyl glycol in a supercritical fluid and bringing the polyalkyl glycol into contact with the fiber. Patent Document 3 discloses a batch process for enhancing the functionality of a polymer surface in which a supercritical fluid in which a solute as a functional material is dissolved in advance is brought into contact with a polymer in a supercritical state, that is, under high pressure. Is disclosed.

  Conventionally, a mask having a hole having a desired shape is provided on the substrate, and a supercritical fluid in which a substance (metal complex) to be deposited on the substrate is dissolved is sprayed from above the mask, and the deposited substance is applied to the substrate surface. A method of forming a pattern of 100 μm or less is also proposed (see, for example, Patent Document 4).

Japanese Patent Laid-Open No. 10-128783 JP 2001-226874 A JP 2002-129464 A JP 2002-313750 A

  The above Patent Documents 1 to 3 disclose polymer surface modification methods using a supercritical fluid as a solvent, and disclose a technique for modifying the entire polymer surface. However, it is difficult to selectively and finely modify a part of the polymer surface with the techniques disclosed in Patent Documents 1 to 3 described above. Moreover, in patent document 4, since a substance (solute) is melt | dissolved in a supercritical fluid and it injects on a polymer substrate, there exists a possibility that the following problems may arise.

  There is a strong correlation between the pressure of the supercritical fluid and the solubility of the solute. When the supercritical fluid is discharged to the outside from a container under high pressure filled with the supercritical fluid in which the solute is dissolved, the pressure of the supercritical fluid is rapidly reduced, and the solubility of the solute is significantly reduced. That is, as described in Patent Document 4, when a solute is dissolved in a supercritical fluid and sprayed onto a polymer, the solute is precipitated at the time of spraying. Therefore, in the technique described in Patent Document 4, the solute can be deposited on the surface of the polymer substrate, but the surface is modified by infiltrating the solute into the polymer substrate as the supercritical fluid penetrates into the polymer substrate. It is not possible.

  The present invention has been made to solve the above problems, and an object of the present invention is to selectively (partially) partially modify a polymer surface by a simpler method using a supercritical fluid. Is to provide a way to do.

  According to the present invention, there is provided a polymer surface modification method using a supercritical fluid, wherein an organic material is added to a predetermined region of the surface of the polymer, and the surface of the polymer to which the organic material is added is added. There is provided a surface modification method comprising contacting a critical fluid to infiltrate the organic material into the polymer surface.

  In the polymer surface modification method of the present invention, when adding an organic substance to a predetermined region of the polymer surface, the organic substance is preferably added to the surface of the polymer in a predetermined pattern.

  The present applicant has previously proposed a technique in which an organic substance is previously applied to the surface of a polymer and a supercritical fluid is brought into contact with the polymer surface to modify the polymer surface (Japanese Patent Application No. 2004-129235). In this application, the following method has been proposed as a method for selectively modifying a part of the polymer surface. First, an organic substance intended to permeate the polymer surface is applied to the entire surface or a wide area of the polymer surface, and then a mold surface having a predetermined uneven pattern is brought into close contact with the polymer surface. Next, the supercritical fluid flows into the space defined between the mold (concave) and the polymer surface, and the applied organic substance is selectively permeated only into the region of the polymer surface into which the supercritical fluid has flowed. Let

  Another object of the present invention is simpler without using a mold having a fine concavo-convex pattern formed as in the method of selectively modifying a part of the polymer surface proposed in Japanese Patent Application No. 2004-129235. It is to provide a method for selectively (partially) modifying a part of a polymer surface in a simple manner.

  The method for modifying the surface of the polymer of the present invention will be described with reference to FIG. First, as shown in FIG. 1 (a), an organic substance 2 is added selectively (partially) to a part of the surface of the polymer 1 in advance (the organic substance 2 is added to the surface of the polymer 1 in a predetermined pattern). . Next, as shown in FIG. 1B, the supercritical fluid 3 is brought into contact with the surface to which the organic substance 2 of the polymer 1 is added, for example, in a sealed container 4. Then, the organic substance 2 penetrates into the polymer 1 together with the supercritical fluid 3. As a result, as shown in FIG. 1C, a polymer 1 in which the organic substance 2 has penetrated only into the portion of the polymer 1 to which the organic substance 2 has been added is obtained. That is, the polymer 1 in which only the portion of the polymer 1 to which the organic substance 2 is added is surface-modified is obtained.

  1C shows an example in which a part of the organic substance 2 has penetrated into the polymer 1, but the present invention is not limited to this. For example, all of the added organic substance 2 is contained in the polymer 1. It may be infiltrated. The permeation amount of the organic substance 2 can be arbitrarily controlled by changing conditions such as the temperature, pressure, and contact time of the supercritical fluid 3 to be contacted. It is preferable to adjust the penetration amount of the organic substance 2 as appropriate.

  In the polymer surface modification method of the present invention as described above, a mold having a fine uneven pattern used in the above Japanese Patent Application No. 2004-129235 is not required, so that the manufacturing cost can be reduced and the process can be reduced. It can be simplified. Further, in the polymer surface modification method of the present invention, the organic substance is previously added to the surface of the polymer in an appropriate pattern. Therefore, the organic substance is brought into contact with the polymer in a state of being dissolved in the supercritical fluid. In addition, the problem that the organic substance is deposited when the supercritical fluid is depressurized is also solved. From the above, according to the polymer surface modification method of the present invention, an organic substance can be permeated into the polymer in a short time and at a high concentration.

  In the polymer surface modification method of the present invention, the pressure of the supercritical fluid is controlled in a state in which the supercritical fluid is in contact with the surface of the polymer (for example, FIG. It is preferable to press with a supercritical fluid. This pressing allows the organic material to penetrate deeper into the polymer. Further, as described above, the supercritical fluid acts as a plasticizer for the polymer and softens the polymer surface. Therefore, when the supercritical fluid is brought into contact with the polymer surface or after that, if the polymer surface is pressed with a mold or the like, the organic substance can efficiently penetrate into the polymer while suppressing deformation of the polymer. It is possible to form a precise pattern on the polymer surface.

  In the polymer surface modification method of the present invention, the supercritical fluid is preferably carbon dioxide in a supercritical state (hereinafter also referred to as supercritical carbon dioxide). Note that various materials can be used as the supercritical fluid, and nitrogen other than supercritical carbon dioxide (supercritical nitrogen) may be used. Supercritical carbon dioxide is particularly suitable as a plasticizer for thermoplastic resin materials since it has a proven record in injection molding and extrusion molding. As the supercritical fluid, air, water, butane, pentane, methanol or the like in a supercritical state may be used, and any fluid can be used as long as it is a fluid that dissolves organic substances to some extent. In order to improve the solubility of the organic substance in the supercritical fluid, the supercritical fluid may be mixed with an entrainer, that is, an alcohol such as acetone, methanol, ethanol, or propanol as an auxiliary agent.

  In the present invention, the conditions such as the temperature and pressure of the supercritical fluid to be brought into contact with the polymer are arbitrary. For example, in the case of carbon dioxide having a temperature at which the supercritical state reaches a temperature of about 31 ° C. and a pressure of about 7 MPa or more, The temperature is preferably in the range of 35 to 150 ° C., and the pressure is preferably in the range of 10 to 25 MPa. If the temperature or pressure is outside the above ranges, the solubility of the organic substance in the supercritical fluid and the permeability to the polymer will be insufficient.

  In the polymer surface modification method of the present invention, the polymer is preferably one selected from the group consisting of polymethyl methacrylate, polycarbonate, wholly aromatic polyamide, wholly aromatic polyester, and amorphous polyolefin. However, in the polymer surface modification method of the present invention, various resins other than the above resins may be used as the polymer. For example, polylactic acid, polyamide, polyetherimide, polyamideimide, polyester, polyacetal, polymethylpentene, polytetrafluoroethylene, liquid crystal polymer, styrene resin, polymethylpentene, polyacetal, etc. Various thermoplastic resins such as a polymer alloy mainly composed of the above and those obtained by blending these with various fillers may be used.

  In the polymer surface modification method of the present invention, the organic substance is preferably an organic substance that dissolves in the supercritical fluid. When an organic substance that dissolves in a supercritical fluid is used, the organic substance penetrates into the polymer in a state dissolved in the supercritical fluid, and thus the organic substance easily penetrates into the polymer.

  In the polymer surface modification method of the present invention, the organic substance is preferably a pigment. For example, when an organic dye material such as an azo dye or a fluorescent dye or phthalocyanine is used as the organic substance, the polymer surface can be dyed.

  In the present invention, an inorganic material modified with various organic substances or organic compounds may be used as a substance that penetrates the surface of a polymer substrate called an organic substance, and particularly, it is soluble to some extent in a supercritical fluid. Any one can be used. Therefore, when a fluorescent material is used as the organic material, not only an organic fluorescent material but also an inorganic fluorescent material can be used. Specifically, the following fluorescent materials can be used.

  A fluorescent substance is a substance that emits fluorescence when irradiated with ultraviolet rays or infrared rays, and can be roughly classified into an inorganic fluorescent material and an organic fluorescent material.

  As organic fluorescent materials, diaminostilbene disulfonic acid derivatives, imidazole derivatives, coumarin derivatives, derivatives such as triazole, carbazole, pyridine, naphthalic acid and imidazolone, dyes such as fluorescein and eosin, and compounds having a benzene ring such as anthracene are used. be able to.

  Further, as the organic fluorescent material, a material that does not dissolve in the supercritical fluid can be used. When an organic fluorescent material that does not dissolve in the supercritical fluid is used, when the supercritical fluid is brought into contact with the polymer surface, the organic fluorescent material added to the polymer surface penetrates into the polymer by the pressure of the supercritical fluid. To do. In this case, it is desirable to use a material having a molecular weight of 5000 or less as the organic fluorescent material in consideration of the size of molecules that can easily penetrate into the polymer substrate.

  As the inorganic fluorescent material, zinc oxide or the like can be used. Further, as colorless inorganic fluorescent materials, the main components are oxides such as Ca, Ba, Mg, Zn, and Cd, crystals such as sulfides, silicates, phosphates, and tungstates, and Mg, Ag, A pigment obtained by adding a metal element such as Cu, Sb or Pb or a rare earth element such as a lanthanoid as an activator and calcining can also be used.

Furthermore, examples of inorganic fluorescent materials that emit red light include Y ₂ O ₃ : Eu, YVO ₄ : Eu, Y ₂ O ₂ S: Eu, 3.5 MgO, 0.5 MgF ₂ GeO ₂ : Mn, (Y , Gd) BO ₃ : Eu, Y (P, V) O ₄ : Eu, or the like can be used.

Examples of inorganic fluorescent materials that emit green light include ZnO: Zn, Zn ₃ SiO ₂ : Mn, Zn ₃ S: Cu, Al, (Zn, Cd) S: Cu, Al, ZnS: Cu, Au, Al. Zn ₂ SiO ₄ : Mn, ZnS: Ag, Cu, (Zn, Cd) S: Cu, ZnS: Cu, Gd ₂ O ₂ S: Tb, La ₂ O ₂ S: Tb, Y ₂ SiO ₅ : Ce, Tb, Zn ₂ GeO ₄ : Mn, CeMgAl ₁₁ O ₁₃ : Tb, SrGa ₂ S ₄ : Eu ²⁺ , ZnS: Cu, Co, MgO · nB ₂ O ₃ : Ce, Tb, LaOBr: Tb, Tm, La ₂ O ₂ S: Tb, ZnS: Cu (Mn), or the like can be used.

Examples of inorganic fluorescent materials that emit blue light include ZnS: Ag, CaWO ₄ , Y ₂ SiO ₅ : Ce, ZnS: Ag, Ga, Cl, Ca ₂ B ₅ O ₃ Cl: Eu ²⁺ , BaMgAl ₁₄ O _23. : Eu ²⁺ , Sr ₃ (PO ₂ ) ₃ Cl: Eu, or the like can be used. And when using the above inorganic fluorescent materials, it is more preferable to chemically solubilize these inorganic fluorescent materials and to solubilize them in a supercritical fluid. In addition, the said fluorescent material can be suitably selected according to a use etc.

  In the polymer surface modification method of the present invention, the organic substance is preferably polyethylene glycol. When polyethylene glycol, polypropylene glycol, polyalkyl glycol or the like is used as the organic substance, the surface of the polymer can be hydrophilized. In particular, since polyethylene glycol dissolves in, for example, supercritical carbon dioxide, it is relatively easy to penetrate into the polymer, and has a hydrophilic group (OH). Therefore, when polyethylene glycol is used as the organic substance, it is preferable because a polymer having a hydrophilic surface can be easily produced. A polymer hydrophilized with polyethylene glycol having excellent biocompatibility is also suitable as a polymer used for biochips, micro TAS (micro total analysis system), and the like. For example, the hydrophilicity of the polymer surface, which is a hydrophobic material, makes it possible to control the fixation of nucleic acids and proteins, and the separation based on the hydrophobization-hydrophobic microregion of the polymer surface separates the nucleic acid according to the hydrophobization rate. It becomes possible.

  In the polymer surface modification method of the present invention, the organic substance is preferably a metal complex. As described above, in the present invention, an inorganic material modified with various organic substances or organic compounds may be used as a substance that penetrates the surface of a polymer substrate called an organic substance, and is particularly soluble to some extent in a supercritical fluid. Anything can be used as long as it does. Examples of the inorganic material that serves as a base for such an organic substance include metal alkoxides and organometallic complexes. When an organometallic complex is used as the organic substance, electroless plating catalyst nuclei can be formed in the polymer. In this case, the polymer surface modification method of the present invention preferably further includes forming a plating layer by electroless plating in the region to which the organic substance has been added.

  In the polymer surface modification method of the present invention, the following organic substances may be used. When a hydrophobic ultraviolet stabilizer such as benzophenone or coumarin is used as the organic substance, the tensile strength after weathering of the polymer can be improved. In addition, when a fluorine compound such as a fluorinated organic copper complex is used as the organic substance, the frictional property of the polymer can be improved or a water repellent function can be provided. Further, when silicon oil is used as the organic substance, a water repellent function is exhibited.

  In the polymer surface modification method of the present invention, it is also possible to use a material that does not dissolve in the supercritical fluid as the organic substance. When an organic substance that does not dissolve in the supercritical fluid is used, when the supercritical fluid is brought into contact with the polymer surface, the organic substance partially added (applied) to the polymer surface is caused by the pressure of the supercritical fluid. Penetrates into the polymer. In this case, any material can be used as the material for the organic substance, but it is desirable to use a material having a molecular weight of 5000 or less in consideration of the molecular size of the organic substance that can easily penetrate into the polymer. However, when using inorganic materials such as fine metal particles, carbon nanotubes, fullerenes, nanohorns such as nanohorns, titanium oxide, etc., these inorganic materials can be solubilized in a supercritical fluid by chemical and physical modification. desirable.

  In the polymer surface modification method of the present invention, as a method for selectively (partially) adding an organic substance to a predetermined region on the surface of the polymer, the organic substance is liquefied and applied to a screen printing method or an inkjet method. A method of adding by a printing method is preferable. As another method, a method of applying a solution containing an organic substance after a resist mask manufactured using a metal mask or a photolithography method is placed on a polymer may be employed. Examples of the method for liquefying an organic substance include a method for softening an organic substance by heating, a method for dissolving an organic substance in a predetermined solvent, and the like, but it dissolves in a solvent because it is not necessary to adjust the temperature. The method is simple and suitable.

  In the polymer surface modification method of the present invention, adding an organic substance to a predetermined region of the polymer surface forms a predetermined groove pattern on the polymer surface, and the organic substance is added to the groove pattern. It is preferable to include adding.

  In the polymer surface modification method of the present invention, it is desirable that a predetermined concavo-convex pattern is provided on the polymer surface to which the organic substance is added by molding or the like. For example, when a groove pattern is formed on the polymer surface, the groove pattern can be used as a guide when an organic substance is added to a part of the polymer surface (predetermined pattern).

  As described above, when an organic substance is added to a flat polymer surface by a screen printing method or an ink jet printing method, it is technically difficult to form a fine pattern of 100 μm or less at present. In addition, when an organic substance is added to a flat polymer surface, if a supercritical fluid is brought into contact with the polymer surface, it may be difficult to form a fine pattern due to bleeding of the pattern of the organic substance. However, for example, when an uneven pattern having a width or depth of 100 μm or less, more desirably 50 μm or less, and even more desirably 10 μm or less is formed on the polymer surface, and an organic substance is added to the uneven pattern portion by, for example, an inkjet method or the like. The organic substance is stretched along the concavo-convex pattern portion by capillary action, and a finer pattern of the organic substance can be formed on the polymer surface.

  In addition, when this method is used, the organic material has entered the concavo-convex pattern, making it difficult for the organic material pattern to bleed even when a supercritical fluid is brought into contact with the polymer surface, thereby compensating for the size and accuracy of the organic material pattern. It becomes possible. Furthermore, when a predetermined fine concavo-convex pattern is formed on the polymer surface, when the polymer comes into contact with the supercritical fluid, organic substances added inside the concavo-convex pattern are prevented from eluting and diffusing to the supercritical fluid side. The effect to do is also increased. The concave / convex pattern formed on the polymer surface is preferably a concave pattern such as a groove pattern, but it is also possible to form a convex pattern and use a valley between the convex patterns.

  In the polymer surface modification method of the present invention, the surface of the polymer to which the organic substance is added is preferably three-dimensional.

  In the polymer surface modification method of the present invention, it is preferable that the method further includes forming a coating layer so as to cover the organic substance added to a predetermined region of the polymer surface.

  By covering the organic substance with the coating layer, when the supercritical fluid is brought into contact with the polymer, the organic substance that is dissolved in the supercritical fluid and is in a fluid state does not scatter outside from the vicinity of the surface of the polymer. Therefore, when the organic material is covered with the coating layer, the organic material dissolved in the supercritical fluid can efficiently penetrate into the polymer at a high concentration. In addition, since the organic material is covered with the coating layer, the organic material can be permeated without bleeding the predetermined pattern of the organic material added onto the polymer, and the region of the predetermined pattern to be modified on the surface of the polymer is increased. It can be modified with accuracy.

  Further, in the polymer surface modification method of the present invention, adding an organic substance to a predetermined region of the polymer surface forms a mask layer having an opening of a predetermined pattern in contact with the polymer; Preferably, the method includes forming the organic material layer in at least the opening of the mask layer and forming a coating layer on the organic material layer.

  Also in this case, since the organic material layer is covered with the coating layer and the mask layer, when the supercritical fluid is brought into contact with the polymer, the organic material dissolved in the supercritical fluid is in a fluid state. The organic substance can be efficiently penetrated into the polymer at a high concentration without scattering from the vicinity of the surface to the outside. Further, since the organic material is covered with the coating layer and the mask layer, the organic material can be permeated without bleeding the predetermined pattern of the organic material added on the polymer, and the predetermined pattern to be modified on the surface of the polymer can be obtained. The region can be modified with high accuracy.

  Note that the mask layer can shield the supercritical fluid, and is a material that adheres / adheres to the surface of the polymer. Further, after the treatment for bringing the supercritical fluid into contact with the polymer, the polymer is damaged. Any material can be used as long as it can be removed without leaving it. By forming the mask layer with a material having such properties, it is possible to prevent the supercritical fluid from entering the polymer region to which the mask layer is adhered / adhered. As the material having such properties, a polymer material can be used, and for example, a photosensitive resin, a thermoplastic resin, a thermosetting resin, and the like are preferable. In particular, a photosensitive resin material is suitable because a predetermined pattern can be easily formed on a polymer and adhesion to the polymer is easy. For example, an oligomer such as polyester acrylate, epoxy acrylate, urethane acrylate, or silicone acrylate is used as a base material. The material etc. which were mix | blended as can be used. Further, when a thermoplastic resin is used for the polymer substrate, it is preferable to use a positive resist 1805 (manufactured by Shipley Far East). This photosensitive resin material can shield the supercritical fluid, and is a material that adheres / adheres to the surface of the polymer, and propanol, butanol, ethanol, methanol, or the like can be used for removal. Therefore, it is possible to perform the treatment without damaging the polymer substrate even when removing the mask layer.

  In the polymer surface modification method of the present invention, in order to shield the supercritical fluid and suppress damage to the polymer substrate in a region other than the opening of the mask layer, the mask layer and the polymer substrate An underlayer that exhibits the above effect may be provided between the two.

  In addition, as a method for forming the mask layer, any method can be used as long as it is a method capable of forming a mask layer having an opening in a region to be modified on the surface of the polymer. In particular, a liquefied photosensitive resin is used. It is preferable to form a mask layer by adhering a mask material such as the above to a region other than the region to be surface-modified of the polymer by a printing method such as a screen printing method or an ink jet method, and curing. As another method for forming the mask layer, a photosensitive resin is applied to the entire surface of the polymer, and then the photosensitive resin in the region to be surface-modified on the polymer is removed using a metal mask or a photolithography method. Thus, a mask layer can be formed. Examples of the method for liquefying the mask material include a method for softening the mask material by heating, a method for dissolving the mask material in a predetermined solvent, and the like. A method of dissolving the mask material is simple and preferable.

  As the material of the coating layer that can be used in the polymer surface modification method of the present invention, it is preferable to select a material that can relatively permeate the supercritical fluid and suppress the diffusion of the organic substance. . When the coating layer is formed of a material having such properties, as described above, the supercritical fluid in which the organic substance is dissolved is guided to the polymer surface, and the organic substance is prevented from diffusing from the polymer surface, Since the supercritical fluid can be brought into contact with the polymer, the organic substance can efficiently penetrate into the polymer at a high concentration. In the polymer surface modification method of the present invention, the coating layer is preferably formed of a material that is less soluble in the supercritical fluid than the organic substance.

  As a material for the coating layer having the above properties, for example, various water-soluble resins (water-soluble polymers) can be used. Examples of the water-soluble resin include polyvinyl alcohol, polyvinyl pyrrolidone, starch, methyl cellulose, carboxymethyl cellulose, sodium alginate and the like. Further, as other coating layer forming materials, polyethylene oxide, sodium polyacrylate, polyacrylamide, cellulose, polyethylene glycol, polyvinyl pyrrolidone and the like can be used. When the coating layer is formed of a water-soluble resin, the coating layer can be removed by rinsing the polymer with water when removing the coating layer after impregnating the penetrating substance into the polymer substrate. It can be removed without damaging the polymer.

  In the polymer surface modification method of the present invention, the coating layer is preferably formed by one method selected from the group consisting of a dipping method, a roll coating method, a screen printing method and a spray method. In addition, as a method for adding a coating layer on a polymer organic material, any method can be used as long as it can be added so that at least an addition portion of the organic material is coated. Can be used. The thickness of the coating layer is arbitrary as long as the supercritical fluid can easily permeate and the permeation substance does not diffuse. The thickness of the coating layer is appropriately set according to the polymer, organic substance, etc. used. Can do. In general, the thickness of the coating layer is preferably in the range of 5 μm to 200 μm, and is preferably uniform.

  According to the polymer surface modification method of the present invention, an organic substance is added only to a predetermined region (predetermined pattern) of the polymer surface, and a supercritical fluid is brought into contact with the polymer surface, thereby partially changing the surface of the polymer. It can be modified. Therefore, the polymer surface can be selectively and finely modified.

  Further, according to the polymer surface modification method of the present invention, when a fine pattern of the organic material is formed on the polymer surface, the organic material is added to a predetermined region of the polymer surface by an inkjet method or a screen printing method. Since a mold for forming a fine pattern is not required, the cost is low and the process is simplified.

  Furthermore, in the polymer surface modification method of the present invention, an organic substance that exhibits various functions can penetrate into the inside of the polymer, so that a functional polymer that maintains the function of the organic substance and has excellent weather resistance is provided. can do.

  In the polymer surface modification method of the present invention, when an organic substance applied to a predetermined region of the polymer is covered with a coating layer or a coating layer and a mask layer, the supercritical fluid is brought into contact with the polymer. The organic substance dissolved in the supercritical fluid is not scattered from the vicinity of the surface of the polymer to the outside, and the organic substance can efficiently penetrate into the polymer at a high concentration. Further, in this case, the organic material can be permeated without bleeding the predetermined pattern of the organic material added on the polymer, and the region of the predetermined pattern to be modified on the surface of the polymer can be modified with high accuracy.

  Examples of the method for modifying the surface of a polymer according to the present invention will be specifically described below with reference to the drawings, but the present invention is not limited thereto.

  In Example 1, as shown in FIG. 2, the dye 2 is added to the surface of the polymer substrate 1 in a character pattern (“A” and “B”), and the dye 2 is penetrated into the polymer 1 only in that portion. A method for performing the surface modification will be described.

[High pressure equipment used for surface modification]
First, the high-pressure apparatus used for the surface modification method of Example 1 will be described with reference to FIG. FIG. 3 is a schematic configuration diagram of a high-pressure apparatus used in the surface modification method of this example. As shown in FIG. 3, the high-pressure device 100 mainly includes a high-pressure vessel 11, a CO ₂ cylinder 12, a supercritical fluid adjustment device 13, and pipes 16 a and 16 b that connect those components. .

  As shown in FIG. 3, the high-pressure vessel 11 includes a container main body 33 having a concave portion 31 formed on the surface and a lid 34, and an O-ring 32 is provided on the upper surface of the outer wall of the concave portion 31 of the container main body 33. Yes. And as shown in FIG. 3, the recessed part 31 of the container main body 33 is sealed by mounting the lid | cover 34 on the upper surface at the side of the recessed part of the container main body 33, and bolting. Further, as shown in FIG. 3, the high-pressure vessel 11 is formed with a flow path 36 and an introduction port 35 that are in communication with the recess 31 of the vessel body 33. Further, as shown in FIG. 3, the flow path 36 circulates with a pipe 16b through which an external supercritical fluid flows through the inlet 35, and the supercritical fluid generated outside the high-pressure vessel 11 is piped. It is efficiently introduced into the recessed portion 31 of the sealed container body 33 from 16 b through the inlet 35 and the flow path 36. At this time, since the concave portion 31 of the container body 33 is sealed by the lid 34 via the O-ring 32, the supercritical fluid introduced into the concave portion 31 via the introduction port 35 and the flow path 36 is retained in the high pressure vessel 11. There is no leakage to the outside.

As shown in FIG. 3, the supercritical fluid adjustment device 13 mainly includes a booster pump 21 and a buffer tank 17. The CO ₂ cylinder 12 and the supercritical fluid adjustment device 13 are connected by a pipe 16a, and the CO ₂ gas introduced from the CO ₂ cylinder 12 through the pipe 16a into the supercritical fluid adjustment device 13 is supplied by a booster pump 21. And introduced into the buffer tank 17. The introduced CO ₂ gas is boosted to a predetermined pressure in the buffer tank 17 and is adjusted to a predetermined temperature by a heater 14 a provided in the buffer tank 17 (supercritical CO ₂ gas in a supercritical state). Carbon). The supercritical carbon dioxide generated in the buffer tank 17 passes through the pipe 16b adjusted to a predetermined temperature by the temperature controller 14b and is sealed from the inlet 35 of the high-pressure vessel 11 through the flow path 36. It is introduced into the recess 31.

[Polymer surface modification method]
Next, a method for modifying the surface of the polymer in this example will be described. First, a polymer substrate 1 having a flat surface was prepared. A polycarbonate resin having a glass transition temperature Tg of about 130 ° C. was used for the polymer substrate 1. Subsequently, the pigment | dye 2 (organic substance) was added to the surface of the polymer substrate 1 by the screen printing method by the predetermined pattern (character pattern). In this example, in order to evaluate the effect of partial surface modification, alphabets “A” and “B” were formed as the pattern of the dye 2 as shown in FIG. Moreover, as the pigment | dye 2 added to the polymer substrate 1, the alcohol solution of dye Blue35 represented by following Chemical formula (1) was used. At this time, the pigment solution was added so that the coating thickness was about 15 μm. Next, the polymer substrate 1 coated with the dye 2 was dried at 70 ° C. for 1 hour, and then cooled at room temperature for 1 hour.

  As described above, a polymer substrate 1 in which the dye 2 was added in a predetermined character pattern on the surface as shown in FIG. 2 was obtained. A schematic cross-sectional view of the polymer substrate 1 at this time is shown in FIG. 1A. At this time, the dye 2 is simply applied on the polymer substrate 1, and the dye 2 is the polymer substrate 1. It does not penetrate inside.

Next, the polymer substrate 1 was installed at the bottom of the recess 31 of the high-pressure vessel 11. Thereafter, the recess 34 in the high-pressure vessel 11 was sealed by placing the lid 34 on the vessel body 33 and tightening the bolt. Next, the supercritical fluid was introduced into the recess 31 in the high-pressure vessel 11 as follows. First, the CO ₂ gas cylinder 12 CO ₂ gas through the booster pump 21 of the supercritical fluid regulator 13 is introduced into the buffer tank 17. The introduced CO ₂ gas is pressurized and heated in the buffer tank 17 to generate supercritical CO ₂ (supercritical carbon dioxide). In this example, supercritical carbon dioxide having a temperature of 40 ° C. and a pressure of 15 MPa was generated. Subsequently, the valve 15b is opened, and the supercritical carbon dioxide adjusted to a predetermined pressure in the buffer tank 17 is sealed in the high-pressure vessel 11 through the inlet 35 and the flow path 36. It was introduced into 31 and allowed to stay (state of FIG. 1 (b)).

  The piping 16b connecting the supercritical fluid adjustment device 13 and the high-pressure vessel 11 is adjusted to a predetermined temperature by a temperature adjustment device 14b (for example, a hot water circulation type temperature adjustment device). Accordingly, the temperature of the supercritical carbon dioxide passing through the pipe 16b can be adjusted. Therefore, it is possible to adjust the temperature in the recess 31 of the high-pressure vessel 11 into which supercritical carbon dioxide has been introduced by the temperature control device 14b. The temperature and pressure in the high-pressure vessel 11 change as the temperature of the supercritical fluid is adjusted, but the temperature and pressure conditions of the supercritical fluid in this embodiment are the same as those before the introduction of the high-pressure vessel 11. It is shown.

  When the supercritical carbon dioxide introduced into the concave portion 31 of the high-pressure vessel 11 comes into contact with the surface of the polymer substrate 1, the dye 2 partially added to the surface of the polymer substrate 1 is dissolved in the supercritical carbon dioxide, It penetrates into the polymer substrate 1 together with the critical carbon dioxide.

  Next, the release valve 24 in the supercritical fluid adjusting device 13 is opened to open the concave portion 31 in the high-pressure vessel 11 to the atmosphere, and then the polymer substrate 1 is taken out from the high-pressure vessel 11 (state of FIG. 1C). .

  The polymer substrate 1 in a state in which the character pattern of the dye 2 as shown in FIG. That is, it was possible to obtain a polymer substrate 1 made of a polymethyl methacrylate resin partially surface-modified with the dye 2.

  As described above, in the polymer surface modification method of the present invention, since an organic substance such as a pigment can be added to a predetermined portion of the polymer surface by a printing method such as a screen printing method in advance, a fine uneven pattern is formed. The surface of the polymer can be partially modified without using the formed mold. Therefore, it is not necessary to individually manufacture a mold according to the pattern formed on the polymer surface, and the cost can be reduced and the process can be simplified.

[Evaluation of adhesion]
The adhesion of the dye 2 formed on the surface of the polymer substrate 1 obtained by the above process was evaluated. Specifically, the evaluation was performed by immersing the polymer substrate 1 in isopropyl alcohol, which is a good solvent for the pigment material (dye). For comparison, after the dye pigment is screen-printed on the polymer substrate 1, the above-described surface modification treatment (treatment of bringing the pigment material into the polymer substrate by contacting with the supercritical fluid) was not performed (hereinafter, The polymer substrate of Comparative Example 1) was prepared and the adhesion was evaluated. As a result, when the polymer substrate of Comparative Example 1 was immersed in isopropyl alcohol, the dye eluted and the printing disappeared. However, in the polymer substrate 1 produced in this example, the disappearance of the color of the printed portion (character pattern portion) was not observed.

[Cross-section structure]
In the polymer substrate prepared in Example 1 (polymer substrate obtained by partially modifying a predetermined surface region) and the polymer substrate prepared in Comparative Example 1, organic substances (pigments) permeate the polymer substrate surface Was analyzed. Specifically, the concentration distribution of the dye in the thickness direction of the portion of the polymer substrate of Example 1 and Comparative Example 1 where the dye was added was examined. As a measuring method, the polymer substrate is dug from the surface by sputtering, and the relative content of the dye using ESCA (Electron Spectroscopy for Chemical Analysis) (the dye content at each measurement depth with respect to the dye content at a predetermined depth ( However, the change in the scale))) was measured. The results are shown in FIG. In FIG. 8, the horizontal axis represents the depth position in the thickness direction of the polymer substrate, and the vertical axis represents the relative value of the pigment content. The white circles in FIG. 8 are the measurement results of Example 1, and the black circles are the measurement results of Comparative Example 1. The position 0 on the horizontal axis is the outermost surface of the substrate, which is the boundary surface with the printing layer (dye). That is, in the characteristic of FIG. 8, the depth position of the substrate becomes deeper toward the right side in the drawing. As is clear from FIG. 8, it was found that the dye penetrated from the vicinity of the outermost surface of the substrate to the substrate depth of about 400 nm in the polymer substrate produced in Example 1. On the other hand, in the polymer substrate produced in Comparative Example 1, as apparent from FIG. 8, the penetration of the dye into the substrate was hardly observed.

  As is apparent from the above results, the polymer substrate produced in this example has a higher concentration of pigment material penetrating from the surface of the polymer substrate to the interior than the polymer substrate that was not subjected to the surface modification treatment. It was found that the dye was modified so as not to be peeled off in the region of the polymer substrate that had penetrated.

  In Example 2, an example in which the surface modification method of the present invention is applied to a plate used for biochemical analysis or the like called micro TAS will be described. A schematic configuration of the micro TAS produced in this example is shown in FIG.

  In the micro TAS 40 of this example, the pattern 42 of the organic material 43 as shown in FIG. 4A was formed on the polymer substrate 41. As the polymer substrate 41, a flat polymer substrate made of polymethylmethacrylate resin (product name: Delpet 560F, manufactured by Asahi Kasei Kogyo Co., Ltd.) having a glass transition temperature Tg of about 100 ° C. was used. As the organic substance 43 forming the pattern 42, polyethylene glycol (PEG) having an average molecular weight of about 1000 was used. That is, in this example, a surface modification treatment for hydrophilizing the surface region to which PEG 53 has been added was performed by adding PEG 43 to a predetermined region on the surface of the polymer substrate 1 and bringing it into contact with the supercritical fluid.

  As shown in FIG. 4A, a pattern 42 of the organic material 43 includes a circular portion 42a into which a liquid sample is injected, and a flow path 42b extending from the circular portion 42a along the longitudinal direction of the polymer substrate 41. And three branch channels 42c divided from the middle of the channel 42b, and three small circular portions into which the reagent formed at the tip of each of the three branch channels 42c is injected. In this example, the diameter of the circular portion 42a is 5 mm, the diameter of the small circular portion 42d is 2 mm, and the widths of the channel 42b and the small channel 42c are 300 μm. In this example, the surface of the polymer substrate 1 is a flat surface. The pattern 42 of PEG 43 was printed on the polymer substrate 41 by screen printing and added. At this time, PEG 43 softened by heating to 60 ° C. was added to the surface of the polymer substrate 41 by screen printing.

  Next, the polymer substrate 41 on which the PEG 43 pattern 42 was formed by screen printing was placed in the recess 31 of the high-pressure vessel 11 used in Example 1, and the inside of the high-pressure vessel 11 was sealed. Next, in the same manner as in Example 1, the surface of the polymer substrate 41 was brought into contact with supercritical carbon dioxide so that the PEG 43 penetrated into the polymer substrate 41. At this time, supercritical carbon dioxide having a pressure P = 15 MPa and a temperature of 50 ° C. was introduced into the high-pressure vessel 11 and retained, and after maintaining the pressure P of the supercritical carbon dioxide, the state was maintained for 30 minutes. . As a result, the PEG 43 applied to the surface of the polymer substrate 41 is dissolved in the supercritical carbon dioxide and penetrates into the polymer substrate 41 together with the supercritical carbon dioxide. However, at this time, supercritical carbon dioxide also contacts a portion to which PEG 43 is not added. However, since PEG 43 is not added to this portion, the surface of the polymer substrate 41 in this portion is not modified.

  Next, the inside of the high-pressure vessel 11 was opened to the atmosphere in the same manner as in Example 1, and the polymer substrate 41 was taken out from the high-pressure vessel 11. In this manner, micro TAS 40 made of polymethyl methacrylate resin in which PEG 43 permeated only into the pattern 42 portion on the surface of the polymer substrate 41, that is, only the portion to which PEG 43 was added, was obtained. In the micro TAS 40 manufactured in this example, only the surface portion (the pattern 42 portion) of the polymer substrate 41 into which PEG 43 has permeated is hydrophilized.

  Next, the wettability on the surface of the micro TAS 40 of this example produced as described above was evaluated. In this evaluation, a micro TAS (hereinafter, referred to as a micro TAS of Comparative Example 2) that was not subjected to surface modification treatment (treatment for infiltrating PEG by contacting with a supercritical fluid) was also prepared and wetted for comparison. Sex was evaluated. As a result, in the micro TAS of Comparative Example 2, the water contact angle of the surface portion to which PEG was added was about 55 °, whereas the micro TAS 40 (micro TAS subjected to surface modification treatment) was used. ), The contact angle of water on the surface to which PEG was added was about 10 °. That is, like the micro TAS 40 produced in this example, by performing surface modification treatment (contact with supercritical carbon dioxide), the wettability of the portion to which PEG is added is greatly improved (hydrophilicity is improved). Improved). In addition, when a water droplet is dropped near the circular portion 42a formed on the micro TAS 40 manufactured in this example, the water is transmitted along the flow passage 42b and the branch flow passage 42c and reaches the small circular portion 42d. It could be confirmed.

  Moreover, when the microTAS40 of this example was immersed in water for 24 hours and then the wettability was confirmed again, the contact angle of water hardly changed. Furthermore, after the micro TAS 40 of this example was left in the atmosphere for 10 months, the wettability of the region to which PEG was added was confirmed. The contact angle of water was 13 °, and good wettability was maintained. I understood that. This is considered to be because wettability is stably maintained because PEG penetrates into the polymer at a high concentration.

  In Example 3, as in Example 2, an example in which the surface modification method of the present invention is applied to a micro TAS will be described. However, in this example, a surface modification method suitable for forming a finer organic substance pattern on the polymer substrate than in Example 2 will be described.

  A schematic configuration diagram of the micro TAS produced in this example is shown in FIG. In the micro TAS 50 of this example, as shown in FIGS. 5A and 5B, the surface of the polymer substrate 51 is similar to the pattern of PEG formed on the surface of the polymer substrate of the micro TAS manufactured in Example 2. A groove pattern 52 was formed, and PEG 53 was added in the groove pattern. In the micro TAS 50 of this example, the dimensions of the groove pattern 52 are as follows. The diameter of the circular part 52a is 5 mm, the widths of the flow path 52b and the branch flow path 52c are both 100 μm, the diameter of the small circular diameter part 52d is 2 mm, and the depths of the circular part 52a, the small circular diameter part 52d and the groove pattern 52 are In either case, the thickness was 100 μm. In this example, PMMA (polymethyl methacrylate) resin is used as the polymer substrate 51, and PEG (polyethylene glycol) 53 is used as an organic substance added to the inside of the groove pattern 52. The micro TAS 50 of this example was manufactured as follows.

  First, a mold having an uneven pattern opposite to the groove pattern 52 formed on the polymer substrate 51 is prepared, and a groove pattern 52 as shown in FIG. 5 is formed on the surface by injection molding using the mold. A polymer substrate 51 was prepared. In this example, the concavo-convex pattern on the mold is formed by precision machining, but the concavo-convex pattern may be formed on the mold by applying a lithography method.

  Next, as shown in FIG. 5A, PEG 53 was added by the ink jet method along the groove pattern 52 of the polymer substrate 51 formed by the above-described method. At this time, PEG 53 heated to 60 ° C. and softened was discharged from the ink jet head and added to the inside of the groove pattern 52 formed on the surface of the polymer substrate 51. If PEG 53 protrudes from the groove pattern 52 in this step, it is preferable to remove the unnecessary PEG 53 by wiping with water or alcohol.

  After adding PEG 53 into the groove pattern 52 of the polymer substrate 51, supercritical carbon dioxide is brought into contact with the surface of the polymer substrate 52 in the same manner as in Example 2 so that the PEG 53 is applied to the groove pattern portion 52 of the polymer substrate 52. The surface was modified by permeation (hydrophilized). Thus, the micro TAS50 of this example was obtained. When the micro TAS is manufactured by the method as described above, an organic substance can be added on the polymer substrate with a pattern of 100 μm or less, and a micro TAS in which only a finer pattern portion is surface-modified can be manufactured.

  Further, the wettability of the micro TAS 50 produced in this example was evaluated in the same manner as in Example 2. As a result, the same result as in Example 2 was obtained. That is, it was confirmed that the wettability was improved only in the pattern portion infiltrated with PEG, became hydrophilic, and was stably maintained.

  In Example 4, an example will be described in which the polymer surface modification method of the present invention is applied to a polymer substrate having a three-dimensional surface. Specifically, in this example, when circuit wiring is performed on a module substrate of a one-chip type lens module that integrally includes a lens and an image sensor that detects image formation by the lens as an electrical signal, An example in which the polymer surface modification method is applied will be described.

  A schematic configuration of the lens module manufactured in this example is shown in FIG. As shown in FIGS. 6A and 6B, the lens module 60 manufactured in this example includes a base member 61 (polymer substrate), a lens 62, and an image sensor 63. One surface 61a (upper surface in FIG. 6A) of the substrate 61 is a substantially flat surface, and the other surface 61b (lower surface in FIG. 6A) is a concave solid surface. As shown in FIG. 6A, the lens 62 is mounted integrally with the base 61 on the central portion of the flat surface 61a of the base 61, and the image sensor 63 has a bottom 61e of the concave three-dimensional surface 61b. Installed on top. And in the lens module 60 of this example, as shown in FIG.6 (b), the some solid wiring 64 which connects the upper part 61d and the bottom part 61e of the concave solid surface 61b of the base material 61 is formed. The three-dimensional wiring 64 is a wiring necessary for mounting the image sensor on the concave three-dimensional surface 61 b of the base material 61.

  As the substrate 61, a polymer substrate made of amorphous polyolefin having a glass transition temperature Tg of about 145 ° C. was used.

  The three-dimensional wiring 64 was formed of a Cu film. A manufacturing method of the three-dimensional wiring 64 is as follows. First, a plating base is formed in a region corresponding to the wiring pattern on the concave three-dimensional surface 61b of the substrate 61. Specifically, a hexane solution of bis (acetylacetonato) palladium metal complex (organic substance) is added to the wiring pattern portion on the concave three-dimensional surface 61b of the substrate 61 by an ink jet printing method. Next, in the same manner as in Example 2, the base 61 is brought into contact with supercritical carbon dioxide, and the metal complex added to the wiring pattern portion of the concave three-dimensional surface 61b is permeated into the base 61 and stabilized. In addition, platinum dimethyl (cyclooctadiene), bis (cyclopentadienyl) nickel, bis (acetylacetonate) palladium, etc. should be used as a metal complex that can be dissolved in supercritical carbon dioxide and reduced to become a plating nucleus. You can also.

  Thereafter, the substrate 61 was immersed in a reducing agent (sodium borohydride) to reduce the metal complex to form metal fine particles. In this way, a plating base was formed in a region corresponding to the wiring pattern on the concave three-dimensional surface 61b of the substrate 61.

  Next, Cu was plated on the concave solid surface 61b side of the substrate 61 by electroless plating. At this time, the Cu film grows only in a portion (plating base portion) where the metal complex has permeated and the surface is modified. In this example, a 10 μm thick Cu film was formed. Thus, the three-dimensional wiring 64 made of the Cu film was formed on the three-dimensional surface 61b of the base member 61 as shown in FIG. As described above, when the polymer substrate to which the surface modification method of the present invention is applied has a three-dimensional structure as in this example, an organic substance is formed on the three-dimensional portion (uneven portion) by performing pattern printing by an ink jet method. Can be added. Therefore, by using the surface modification method of the present invention, wiring to a three-dimensional part, which has been impossible in the past, can be made possible.

  Next, the adhesion of the three-dimensional wiring 64 of the lens module 60 produced in this example was evaluated. Specifically, a peeling test using an adhesive tape was performed on the three-dimensional wiring 64 formed on the three-dimensional surface 61 b of the base material 61. For comparison, a lens module (hereinafter, referred to as a lens module of Comparative Example 3) that does not undergo surface modification treatment (treatment of allowing a metal complex to permeate through contact with supercritical carbon dioxide) on the three-dimensional surface 61b of the substrate 61 is manufactured. Then, the adhesion was examined. The results are shown in FIG. As is clear from FIG. 7, in the lens module of Comparative Example 3, the three-dimensional wiring was easily peeled off in the peeling test. On the other hand, in the lens module 60 of this example, it was found that the three-dimensional wiring 64 was difficult to peel off, and the adhesion was greatly improved. Furthermore, when the adhesion of the three-dimensional wiring 64 was confirmed after leaving the lens module after the surface modification treatment in the atmosphere for 10 months, it was found that it was difficult to peel off and good adhesion was maintained.

  In Example 5, as shown in FIG. 9, the fluorescent substance 72 is added with a character pattern (“A” and “B”) on the surface of the polymer substrate 71, and the fluorescent substance (fluorescent material) is applied only to that portion to the polymer 71 A method of surface modification (fluorescence image formation) by penetrating into the inside will be described. Here, before describing the surface modification method of Example 5, the use and problem of using a fluorescent material as an organic substance will be described.

  Conventionally, a technique for adding a fluorescent material on a polymer has been applied as a technique for improving the security of printed matter (card), for example. When various information is printed on a printed material with fluorescent material, it cannot be visually recognized under normal visible light, but an image that can be visually recognized only with a specific light other than visible light. Since it appears, it is possible to improve the security of the printed matter (card). Therefore, conventionally, in order to prevent information printed on printed matter (card) from being easily destroyed and to prevent the fluorescent material from being peeled off, a cover sheet, a protective layer, etc. are provided to protect the printed portion. A method has been proposed. For example, in Japanese Patent Application Laid-Open No. 10-320499, a fluorescent image forming layer is covered with an oversheet. In addition, as a conventional example of using a luminescent material in the manufacture of a forgery-preventing card, for example, in JP-A-02-225091, a forgery-preventing luminescent identification card printed with a luminescent identification mark of a fluorescent paint has been proposed, In this patent document, a fluorescent paint issue identification mark is covered with a laminate film.

However, the conventional techniques as described above have the following problems.
(1) The number of oversheet coating steps increases, resulting in an increase in cost, and it is impossible to produce a card that is cheap and easy to prevent forgery.
(2) When the card is left on a dashboard of an automobile for a long time under a hot sun, for example, the guard may be exposed to a high temperature and the oversheet may peel off.
(3) Moreover, there is a possibility that the card may be forged or altered if the oversheet is intentionally peeled off.
(4) If the oversheet is not covered, the printed surface may be blurred due to scratching with other articles, etc. when storing or carrying the card, or the card's surface layer may be scratched by other articles. There is also a risk that it may be peeled off and the appearance and function of the card may be impaired.

  Example 5 was made in order to solve the above-mentioned problems, and suppresses the increase in manufacturing cost, prevents forgery and can easily verify the authenticity, and has excellent durability, abrasion resistance, and the like of the printed part. A method for surface modification of a polymer to provide a card. Hereinafter, the polymer surface modification method of Example 5 will be described in detail with reference to the drawings.

[Method for surface modification of polymer substrate]
A method for modifying the surface of the polymer substrate in this example will be described with reference to FIGS. In this example, the same high-pressure apparatus as used in Example 1 (the high-pressure apparatus in FIG. 3) was used as the high-pressure apparatus for contacting the polymer substrate with the supercritical fluid.

  First, a polymer base 71 having a flat surface was prepared. A polycarbonate resin having a glass transition temperature Tg of about 130 ° C. was used for the polymer substrate 71. Next, the fluorescent material 72 was added in a predetermined pattern (character pattern) to the surface of the polymer substrate 71 by screen printing. As the fluorescent substance 72, a quinazolone derivative (manufactured by Nippon Fluorescent Chemical Co., Ltd., trade name: Lumicol 1000) which is an organic fluorescent substance was used. In this example, in order to evaluate the effect of partial surface modification, alphabets “A” and “B” were formed as the pattern of the fluorescent material 72 as shown in FIG. At this time, the organic fluorescent substance solution was added so that the coating thickness was about 15 μm. Next, the polymer substrate 71 coated with the fluorescent material 72 was dried at 70 ° C. for 1 hour, and then cooled at room temperature for 1 hour.

  As described above, a polymer substrate 71 was obtained in which the fluorescent material 72 was added to the surface as shown in FIG. 9 in a predetermined character pattern. FIG. 10A shows a schematic cross-sectional view of the polymer base material 71 at this time. At this time, the fluorescent material 72 is simply applied on the polymer base material 71, and the fluorescent material 72 is shown in FIG. Does not penetrate into the polymer substrate 71.

  Next, a coating layer 73 was formed on the polymer substrate 71 so as to cover the fluorescent material 72 formed in a character pattern (state of FIG. 10B). Specifically, the coating layer 73 was formed as follows. In this example, polyvinyl alcohol was used as a material for forming the coating layer 73. First, polyvinyl alcohol was applied to the entire surface of the polymer substrate 71 on the side where the fluorescent material 72 was added by spin coating. At this time, the coating thickness was about 100 μm. Next, the polymer substrate 71 coated with polyvinyl alcohol was dried at 70 ° C. for 1 hour, and then cooled at room temperature for 1 hour. In this way, the coating layer 73 was formed on the polymer substrate 71. At this point in time, the fluorescent material 72 added on the polymer base material 71 is only covered with the coating layer 73, so that the fluorescent material 72 does not penetrate into the polymer base material 71.

Next, the polymer substrate 71 was installed at the bottom of the recess 31 of the high-pressure vessel 11. Thereafter, the recess 34 in the high-pressure vessel 11 was sealed by placing the lid 34 on the vessel body 33 and tightening the bolt. Next, the supercritical fluid was introduced into the recess 31 in the high-pressure vessel 11 as follows. First, the CO ₂ gas cylinder 12 CO ₂ gas through the booster pump 21 of the supercritical fluid regulator 13 is introduced into the buffer tank 17. The introduced CO ₂ gas is pressurized and heated in the buffer tank 17 to generate supercritical CO ₂ (supercritical carbon dioxide). In this example, supercritical carbon dioxide having a temperature of 40 ° C. and a pressure of 15 MPa was generated. Next, the valve 15 b is opened, and the supercritical carbon dioxide 5 adjusted to a predetermined pressure in the buffer tank 17 is sealed in the high-pressure vessel 11 through the inlet 35 and the flow path 36 of the high-pressure vessel 11. It was introduced into the recess 31 and allowed to stay (state shown in FIG. 10C).

  The piping 16b connecting the supercritical fluid adjustment device 13 and the high-pressure vessel 11 is adjusted to a predetermined temperature by a temperature adjustment device 14b (for example, a hot water circulation type temperature adjustment device). Accordingly, the temperature of the supercritical carbon dioxide passing through the pipe 16b can be adjusted. Therefore, it is possible to adjust the temperature in the recess 31 of the high-pressure vessel 11 into which supercritical carbon dioxide has been introduced by the temperature control device 14b. Note that the temperature and pressure in the high-pressure vessel 11 change by adjusting the temperature of the supercritical fluid, but the temperature and pressure conditions of the supercritical fluid in this embodiment are the states before the introduction of the high-pressure vessel 11. Is shown.

  When the supercritical carbon dioxide 5 introduced into the concave portion 31 of the high-pressure vessel 11 comes into contact with the coating layer 73 side of the polymer substrate 71, first, the supercritical carbon dioxide 5 permeates the coating layer 73. Next, the supercritical carbon dioxide 5 reaches the fluorescent material 72 covered with the coating layer 73, and the fluorescent material 72 is dissolved in the supercritical carbon dioxide 5. Then, the fluorescent material 72 dissolved in the supercritical carbon dioxide 5 penetrates into the polymer substrate 71 together with the supercritical carbon dioxide 5. At this time, the fluorescent material 72 is dissolved in the supercritical carbon dioxide 5 and is in a fluid state. However, since the fluorescent material 72 is covered with the coating layer 73, the fluorescent material 72 diffuses from the surface of the polymer substrate 71 to the outside. Can be suppressed. As a result, compared with the case where the coating layer 73 is not formed, the fluorescent material 72 can be efficiently penetrated into the polymer base material 71 at a high concentration. Further, when the coating layer 73 is formed so as to cover the fluorescent material 72 added in a predetermined pattern on the polymer substrate 71 as in the present embodiment, the in-plane direction of the polymer substrate 71 of the fluorescent material 72 Can be suppressed, so that the bleeding of the pattern of the fluorescent material 72 is suppressed. Therefore, it is possible to form a finer pattern with higher definition than when the coating layer 73 is not formed.

  Next, the release valve 24 in the supercritical fluid adjusting device 13 is opened to open the concave portion 31 in the high-pressure vessel 11 to the atmosphere, and then the polymer substrate 71 is taken out from the high-pressure vessel 11 (the state shown in FIG. 10D). ). At this time, after supercritical carbon dioxide in the high-pressure vessel 11 was discharged, after returning to room temperature, the high-pressure vessel 11 was opened and the polymer substrate 71 was taken out. Next, the polymer substrate 71 is washed with water to remove the coating layer 73, and the polymer substrate 71 is further washed with isopropyl alcohol to remove the fluorescent material 72 remaining on the surface of the polymer substrate 71 (FIG. 10 (e)). ) State).

  On the surface of the polymer substrate 71 obtained by the above-described process, the character pattern of the fluorescent material 72 did not exist in a state that can be visually confirmed. Therefore, the polymer base material 71 was irradiated with light using a light source containing a large amount of ultraviolet components called black light. As a result, the light emission by the fluorescence of the character pattern as shown in FIG. 9 was confirmed. Thereby, in the polymer base material 71 obtained by the above-mentioned process, it has confirmed that the character pattern of the fluorescent substance 72 as shown in FIG. As described above, a polymer substrate 71 made of a polycarbonate resin whose surface was partially modified with the fluorescent material 72 could be obtained. In this embodiment, in order to detect the fluorescent material that has penetrated into the polymer substrate, the above-described black light is used to irradiate the polymer substrate with ultraviolet rays. At this time, the visible light emitted from the fluorescent material by the ultraviolet irradiation is used. The presence of the fluorescent material was detected by visually recognizing the fluorescence of the light.

  As described above, in the polymer surface modification method of Example 5, a fluorescent material can be added to a predetermined portion of the polymer surface by a printing method such as a screen printing method in advance, so that a fine uneven pattern was formed. The surface of the polymer can be partially modified without using a mold, so that the cost can be reduced and the process can be simplified. In addition, since the fluorescent material is coated with a coating layer and brought into contact with the supercritical fluid, the fluorescent material can be prevented from diffusing into the supercritical fluid, and as a result, the fluorescent material can penetrate into the substrate at a high concentration. In addition, high-definition patterns can be formed.

[Comparative Example 4]
In Comparative Example 4, after the fluorescent material 72 was added to the polymer substrate 71 by screen printing, a coating layer was not formed, and the surface modification treatment (contacted with a supercritical fluid to bring the fluorescent material 72 into a polymer group). The polymer base material (hereinafter referred to as the polymer base material of Comparative Example 4) was produced without performing the treatment for infiltrating the material 71. In the polymer base material 71 of Comparative Example 4, since the fluorescent material 72 is simply printed on the surface, the character pattern of the fluorescent material 72 is present on the surface of the polymer base material 71 in a visible state. In addition, the same material as Example 5 was used for the polymer base material 71 and the fluorescent substance 72.

[Durability evaluation]
In this example, the following two types of tests were performed in order to evaluate the durability of the printed part (character pattern part) on the surface of the polymer substrate modified by the surface modification method of this example.

  First, as a first durability evaluation test, the adhesion of the fluorescent material 72 formed on the surface of the polymer substrate 71 obtained in Example 5 and Comparative Example 4 was evaluated. Specifically, evaluation was performed by immersing the polymer substrate 71 in isopropyl alcohol, which is a good solvent for the fluorescent material. As a result, when the polymer base material of Comparative Example 4 was immersed in isopropyl alcohol, the fluorescent material eluted and the printing disappeared. At this stage, the character pattern of the fluorescent material did not remain on the surface of the polymer substrate in a state where it was visible. Furthermore, after the polymer base material of Comparative Example 4 was immersed in isopropyl alcohol, the surface of the polymer base material of Comparative Example 4 was irradiated with ultraviolet light with black light, but no fluorescence was confirmed. That is, when the adhesion of the polymer substrate of Comparative Example 4 was evaluated, it was found that no fluorescent substance remained on the surface and inside.

  On the other hand, when the adhesion of the polymer substrate 71 produced in Example 5 was evaluated, the surface of the polymer substrate 71 produced in Example 5 was almost in a state where the character pattern of the fluorescent material was visible. Although it did not remain, when the polymer substrate was irradiated with ultraviolet light with black light, it was confirmed that the character pattern was emitted by fluorescence. That is, in the polymer base material 71 of Example 5, it was confirmed that the fluorescent material penetrated into the surface of the polymer base material. The above results show that in the polymer base material of Comparative Example 4, the fluorescent substance does not penetrate into the base material and is easily eluted, whereas in Example 5, the surface modification treatment (super (The treatment of allowing the fluorescent material 72 to permeate the polymer base material 71 by bringing it into contact with the critical fluid), so that the fluorescent material 72 permeates the polymer base material 71 at a high concentration and the fluorescent material 72 is difficult to elute. It is thought that this is because.

  Next, as a second durability evaluation test, the adhesiveness of the printed portion (character pattern) of the fluorescent material formed on the polymer substrate obtained in Example 5 and Comparative Example 4 was evaluated. Specifically, a peeling test using an adhesive tape was performed on the printed part of the fluorescent material. For comparison, a peeling test was similarly performed on the polymer base material of Comparative Example 4. The results are shown in FIG. As is clear from FIG. 12, in the polymer substrate of Comparative Example 4, the printed part of the fluorescent material was easily peeled off in the peeling test (x evaluation in FIG. 12). On the other hand, when the peeling test using the adhesive tape was similarly performed on the character pattern portion (printing portion) of the polymer base material of Example 5, the printed portion of the fluorescent material was hardly peeled off, and the adhesion was It was found that there was a significant improvement (◯ evaluation in FIG. 12). This was confirmed as follows. The polymer base material of Example 5 was irradiated with ultraviolet light with black light before and after the peeling test, and the light emission state of the character pattern by fluorescence was visually confirmed. There was no difference between the light emission state before and after the peeling test. Was not seen. This is because, in the polymer base material of Example 5, the fluorescent material permeates the inside of the surface of the polymer base material, so the printed part of the fluorescent material is difficult to peel off, and the adhesion is greatly improved. Because.

  Further, when the emission state of the fluorescent material was examined after the polymer substrate after the surface modification treatment was left in the atmosphere for 10 months with respect to the polymer substrate of Example 5, the emission state of the character pattern by fluorescence was It was observed for 10 months before being left in the atmosphere (initial state) and unchanged (O evaluation in FIG. 12). Based on the above results, the polymer base material produced in the present example has a fluorescent substance that moves from the surface of the polymer substrate to the inside as compared with the polymer substrate (Comparative Example 4) that was not subjected to the surface modification treatment with the supercritical fluid. It was found that the fluorescent material was modified so that it was difficult to peel off.

[Cross-section structure]
In the polymer substrates produced in Example 5 and Comparative Example 4, the state of penetration of the fluorescent material (penetrating material) into the polymer substrate surface was analyzed. Specifically, the concentration distribution of the fluorescent material in the thickness direction of the polymer substrate in the portion where the fluorescent material of the polymer substrate was added was examined in the same manner as in Example 1. The results are shown in FIG. In FIG. 11, the horizontal axis represents the depth position in the thickness direction of the polymer substrate, and the vertical axis represents the relative value of the content of the fluorescent substance on an arbitrary scale. In addition, the white square mark in FIG. 11 is the measurement result of Example 5, and the black circle mark is the measurement result of Comparative Example 4. As is clear from FIG. 11, in the polymer substrate produced in Example 5, it was found that the fluorescent material penetrated from the vicinity of the outermost surface of the polymer substrate to a depth of about 500 nm. On the other hand, in the polymer base material produced in Comparative Example 4, as apparent from FIG. 11, almost no penetration of the fluorescent substance into the polymer base material was observed.

  From the principle and evaluation results of the surface modification method of the present embodiment, if various information is printed on the printed matter (card) using the surface modification method of the present embodiment, the above-described problems (1) to (4) It can be seen that it is possible to solve the problem. In other words, by using the surface modification method of the present embodiment, it is possible to suppress an increase in manufacturing cost, prevent counterfeiting and easily verify the authenticity, and have excellent wear resistance and durability on the outer surface. Can be provided.

  In Example 6, a polymer substrate (FIG. 9) having the same structure as that of Example 5 was produced by a surface modification method different from that of Example 5. In this example, the polymer substrate, the fluorescent material, and the fluorescent material pattern formed on the polymer substrate were the same as those in Example 5. A method for modifying the surface of the polymer substrate in this example will be described with reference to FIG.

  First, polyvinyl alcohol was thinly applied to the surface of the polymer substrate 71 (an underlayer was formed, not shown). The thickness of polyvinyl alcohol was 0.5 μm. This underlayer is provided in order to easily remove the mask layer without damaging the polymer substrate in the step of removing the mask layer described later.

  Next, a mask layer 76 was formed on the polyvinyl alcohol layer as follows. A mask material was adhered to a region other than the fluorescent material pattern portion 77 (character pattern portion) to be formed on the polymer substrate 71 by an ink jet printing method. In this example, a photosensitive resin (SU-10 manufactured by Kayaku Microchem Co., Ltd.) was used as the mask material, and the coating thickness of the photosensitive resin was about 1 μm. Next, the polymer substrate 71 to which the photosensitive resin was adhered was dried at 70 ° C. for 1 hour, and further cooled at room temperature for 1 hour. Next, the mask material was cured by irradiating the mask material with ultraviolet rays to form a mask layer 76. In this way, a mask layer 76 having the pattern portion 77 of the fluorescent material as an opening was formed on the polymer base material 71 (state shown in FIG. 13A). As the material of the mask layer 76, any material can be used as long as it can shield the supercritical fluid and adheres / adheres to the surface of the polymer substrate 71.

  Next, a fluorescent material was applied to the surface of the polymer base 71 on the mask layer 76 side to form a fluorescent material layer 72 on the mask layer 76 (state shown in FIG. 13B). In this example, as shown in FIG. 13B, the example in which the fluorescent material layer 72 is applied over the entire surface of the mask layer 76 has been described, but the present invention is not limited to this. In the surface modification method of this example, it is necessary to apply a fluorescent material to the opening 77 of the mask layer 76, but it is not necessary to apply the fluorescent material to other regions on the mask layer 76.

  Next, polyvinyl alcohol (coating agent) was applied so as to cover the fluorescent material layer 72 and dried. At this time, polyvinyl alcohol was applied to a thickness of 100 μm to form a coating layer 73 on the fluorescent material layer 72 (state shown in FIG. 13C). At this time, since the fluorescent material layer 72 is only covered with the mask layer 76 and the coating layer 73, the fluorescent material does not penetrate into the polymer substrate 71.

  Next, the polymer base material 71 having the coating layer 73 formed on the fluorescent material layer 72 is placed in the concave portion 31 of the high-pressure vessel 11 (FIG. 3) used in Example 1, and the inside of the high-pressure vessel 11 is sealed. did. Next, supercritical carbon dioxide 5 having a pressure P1 of 15 MPa and a temperature of 50 ° C. was introduced into the high-pressure vessel 11 and retained. And after the pressure of the supercritical carbon dioxide 5 was stabilized, the state was maintained for 30 minutes. At this time, the surface of the polymer substrate 71 is brought into contact with the supercritical carbon dioxide 5, whereby a part of the fluorescent material layer 72 formed in the opening 77 of the mask layer 76 together with the supercritical carbon dioxide 5 is masked. It penetrates from the surface of the polymer substrate 71 exposed at the opening of the layer 76 into the inside (state of FIG. 13 (d)). In this example, the base layer made of the polyvinyl alcohol described above is provided between the fluorescent material layer 72 and the polymer substrate 71, but the polyvinyl alcohol is a substance that allows the supercritical carbon dioxide 5 to pass therethrough. Therefore, as in this example, even if an underlayer made of polyvinyl alcohol is provided between the fluorescent material layer 72 and the polymer substrate 71, the supercritical carbon dioxide 5 is brought into contact with the surface of the polymer substrate 71. In this case, the fluorescent material penetrates into the surface of the polymer substrate 71 together with the supercritical carbon dioxide 5.

  In the polymer base material 71 of this example, the side surface and the top surface of the fluorescent material added on the polymer base material 71 are surrounded by the side wall of the mask layer 76 and the coating layer 72, respectively (being covered). Therefore, the fluorescent substance can be prevented from diffusing from the top of the polymer substrate 71 and can penetrate into the polymer substrate 71 efficiently and at a high concentration. Further, in the polymer base material 71 of this example, since the mask layer 76 is formed on the side portion of the fluorescent material, the polymer base of the fluorescent material dissolved in the supercritical fluid when the fluorescent material penetrates the polymer base material 71. Diffusion in the in-plane direction of the material 71 can be suppressed, and bleeding of the printing pattern (character pattern) of the fluorescent material can be suppressed.

  When the supercritical carbon dioxide 5 is brought into contact with the polymer base material 71 (step of FIG. 13D), the supercritical carbon dioxide 5 also comes into contact with a region other than the opening of the mask layer 76. Since the mask layer 76 is formed in the region, the fluorescent material does not penetrate into the polymer substrate in this region (the surface of the polymer substrate in this region is not modified).

  Next, after the fluorescent material was infiltrated into a predetermined region of the polymer substrate 71, the inside of the high-pressure vessel 11 was opened to the atmosphere in the same manner as in Example 1, and the polymer substrate 71 was taken out from the high-pressure vessel 11 (FIG. 13 ( e) state). Next, the polymer substrate 71 is washed with water to remove the coating layer 73, and the polymer substrate 71 is further washed with isopropyl alcohol or water to remove the resist and the fluorescent material 72 remaining on the surface of the polymer substrate 71 ( FIG. 13 (f) state).

  The polymer base material 71 in a state where the character pattern of the fluorescent material 72 as shown in FIG. That is, it was possible to obtain a polymer substrate 71 made of a polycarbonate resin that was partially surface-modified with the fluorescent material 72.

  As described above, in the polymer surface modification method of Example 6, a mask layer is formed in advance so that a predetermined portion of the polymer surface becomes an opening by a printing method such as an ink jet printing method and penetrates into the opening. Since the substance is added, the surface of the polymer can be partially modified without using a mold having a fine concavo-convex pattern, so that the cost can be reduced and the process can be simplified. In addition, since the fluorescent material is coated with the coating layer and the mask layer and brought into contact with the supercritical fluid, the fluorescent material can be prevented from diffusing into the supercritical fluid, and as a result, penetrates into the substrate at a high concentration. And a high-definition pattern can be formed.

[Durability evaluation]
First, the adhesion of the fluorescent material 72 formed on the surface of the polymer substrate 71 was evaluated in the same manner as in Example 5 for the polymer substrate 71 produced in this example. Specifically, evaluation was performed by immersing the polymer substrate 71 in isopropyl alcohol, which is a good solvent for the fluorescent material. As a result, in the polymer substrate 71 produced in this example, the light emission of the character pattern due to fluorescence was confirmed as in Example 5, and the disappearance of the printed portion (character pattern portion) was not observed. This is because in Example 6, the surface modification process (the process of bringing the fluorescent material 72 into the polymer base material 71 by bringing it into contact with the supercritical fluid) performed the fluorescent material 72 inside the polymer base material 71. It is thought that this is because the fluorescent substance 72 is in a state in which it has permeated at a high concentration and is difficult to elute.

  Moreover, the adhesiveness of the printed part (character pattern) of the fluorescent material formed on the polymer substrate was evaluated in the same manner as in Example 5 for the polymer substrate prepared in this example. Specifically, a peeling test using an adhesive tape was performed on the printed part of the fluorescent material. As a result, the same result as in Example 5 was obtained. That is, in the polymer base material of this example, it was found that the printed part of the fluorescent material was difficult to peel off, and the adhesion was greatly improved. Furthermore, when the polymer substrate after the surface modification treatment was left in the atmosphere for 10 months and the light emission state of the character pattern by fluorescence was confirmed, it was found that the light emission state of the same character pattern as the initial state was maintained. It was. That is, in the polymer base material prepared in this example, the fluorescent material penetrated from the surface of the polymer substrate into the inside as compared with the polymer substrate (Comparative Example 4) that was not subjected to the surface modification treatment with the supercritical fluid. As a result, it was found that the fluorescent material was modified so as not to easily peel off.

  From the principle and evaluation results of the surface modification method of the present embodiment, if various information is printed on the printed matter (card) using the surface modification method of the present embodiment, the above-described problems (1) to (4) It can be seen that it is possible to solve the problem. In other words, by using the surface modification method of the present embodiment, it is possible to suppress an increase in manufacturing cost, prevent counterfeiting and easily verify authenticity, and a card having excellent wear resistance and durability on its outer surface. Can be provided.

  According to the polymer surface modification method of the present invention, a predetermined region (region of a predetermined pattern) on the polymer substrate can be easily surface-modified. In particular, since the surface modification can be easily performed even in a fine region of 100 μm or less, the polymer surface modification method of the present invention is a micro TAS or biochip that requires surface modification of only the fine region, Or it is especially suitable for manufacture of a three-dimensional wiring device etc. When a fluorescent material is used as the penetrating material, the method for modifying the surface of the polymer of the present invention is particularly suitable for a method for producing a highly secure card or the like.

FIGS. 1A to 1C are diagrams showing the procedure of the surface modification method of the present invention. FIG. 2 is a perspective view of the polymer substrate produced in Example 1. FIG. FIG. 3 is a schematic configuration diagram of the high-pressure apparatus used for surface modification of the polymer substrate in Example 1. 4 is a schematic configuration diagram of a micro TAS manufactured in Example 2, FIG. 4 (a) is a perspective view, and FIG. 4 (b) is an AA ′ sectional view in FIG. 4 (a). is there. FIG. 5 is a schematic configuration diagram of a micro TAS manufactured in Example 3, FIG. 5 (a) is a perspective view, and FIG. 5 (b) is a cross-sectional view along BB ′ in FIG. 5 (a). is there. 6 is a schematic configuration diagram of a lens module manufactured in Example 4, FIG. 6A is a cross-sectional view taken along the line CC ′ in FIG. 6B, and FIG. 6B is a three-dimensional surface side. FIG. FIG. 7 is a diagram showing the results of a three-dimensional wiring peeling test of the lens module manufactured in Example 4. FIG. 8 is a graph showing the distribution of the pigment content in the depth direction of the polymer substrate produced in Example 1. FIG. 9 is a perspective view of the polymer substrate produced in Example 5. FIG. FIGS. 10A to 10E are diagrams showing the procedure of the surface modification method of Example 5. FIG. FIG. 11 is a view showing the distribution of the fluorescent substance content in the depth direction of the polymer substrate produced in Example 5. FIG. 12 is a view showing the results of a peeling test of the printed pattern of the fluorescent material formed on the polymer substrate of Example 5. FIGS. 13A to 13F are views showing the procedure of the surface modification method of Example 6. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,71 Polymer substrate 2 Organic substance 3 Supercritical fluid 72 Fluorescent substance 73 Coating layer 76 Mask layer

Claims (5)

A polymer member,
A polymer substrate having a predetermined pattern of grooves formed on the surface,
A polymer member, wherein an organic substance is impregnated in the surface of the groove. The polymer member according to claim 1, wherein the groove has a width of 100 μm or less. The polymer member according to claim 1 or 2, wherein the organic substance is polyethylene glycol. The polymer member according to claim 3, wherein the polymer member is a plate for biochemical analysis. The polymer member according to claim 1, wherein the organic substance is a metal complex, and the polymer member further includes a plating layer on the groove.

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