Resin member, method for producing resin member, and resin product

Abstract

To provide a resin member containing a resin that melts or softens when heated and has a fine three-dimensional structure on its surface, a method for producing the resin member, and a resin product including the resin member.SOLUTION: A resin member contains a resin that melts or softens when heated, and has protrusions on its surface with diameters of 200 nm or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a resin member, a method for manufacturing a resin member, and a resin product. [Background technology]

[0002] Various methods are known for forming a fine three-dimensional structure on the surface of a resin member. For example, Patent Document 1 describes a method for transferring a three-dimensional structure onto the surface of a cured product of an active energy ray-curable composition by contacting the active energy ray-curable composition with a mold having a fine three-dimensional structure formed on the surface thereof and irradiating the composition with ultraviolet rays. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-193447 A Summary of the Invention [Problem to be solved by the invention]

[0004] The method described in Patent Document 1 forms a three-dimensional structure on a cured product of an active energy ray-curable composition, but does not form a three-dimensional structure on the surface of a member containing a resin that has been melted or softened by heating.

[0005] In view of the above circumstances, one embodiment of the present disclosure has an objective of providing a resin member that contains a resin that melts or softens when heated and has a fine three-dimensional structure on its surface, a method for manufacturing the resin member, and a resin product that includes the resin member. [Means for solving the problem]

[0006] Means for solving the above problems include the following embodiments. <1> Contains a resin that melts or softens when heated, A resin member having protrusions on its surface, the protrusions having a diameter of 200 nm or less. <2> The aspect ratio of the protrusion is 0.25 or more. <1> The resin member according to claim 1. <3> The height of the protrusions is 50 nm or more. <1> or <3> The resin member according to claim 1. <4> The protrusions have a region in which the center-to-center distance is 300 nm or less. <1> ~ <3> The resin member according to any one of claims 1 to 5. <5> The number of protrusions is 100 / μm 2 having a region that is greater than or equal to <1> ~ <4> The resin member according to any one of claims 1 to 5. <6> The resin comprises a polyolefin. <1> ~ <5> The resin member according to any one of claims 1 to 5. <7> The polyolefin contains at least one of a side chain having 3 or more carbon atoms or a siloxane bond. <6> The resin member according to claim 1. <8> It is an injection molded product. <1> ~ <7> The resin member according to any one of claims 1 to 5. <9> Providing a template having pores with diameters of 200 nm or less; bringing a resin melted or softened by heating into contact with the mold; The method for producing a resin member includes the steps of: <10> The aspect ratio of the hole is 0.25 or more. <9> 2. A method for producing a resin member according to claim 1 . <11> The method of contacting is an injection molding method. <9> or <10> 2. A method for producing a resin member according to claim 1 . <12> The mold is obtained by anodizing the surface of a substrate containing aluminum. <9> ~ <11> 13. The method for producing a resin member according to claim 12. <13> <1> ~ <8> The resin member according to any one of claims 1 to 5, A resin product selected from the group consisting of water-repellent materials, oil-repellent materials, anti-reflective materials, friction-reducing materials, adhesive materials (substrates for applying adhesives), heat-sealing materials, painting equipment, antibacterial materials, virus inactivation materials, anti-fungal materials, light-collecting materials, cell culture container materials, sound-absorbing materials, heat-dissipating materials, gas-adsorbing materials, and bioabsorbable materials. Effect of the Invention

[0007] According to one embodiment of the present disclosure, there are provided a resin member including a resin that melts or softens when heated and having a fine three-dimensional structure on its surface, a method for producing the resin member, and a resin product including the resin member. [Brief description of the drawings]

[0008] [Figure 1] 2 is an electron microscope photograph of the surface of the resin member produced in Example 1. [Diagram 2] 1 is an electron microscope photograph of the surface of the resin member produced in Example 2.

[0009] In the present disclosure, a numerical range indicated using "~" indicates a range that includes the numerical values ​​before and after "~" as the minimum and maximum values, respectively. In the numerical ranges described in stages in this disclosure, the upper or lower limit value described in a certain numerical range may be replaced by the upper or lower limit value of another numerical range described in stages, or may be replaced by a value shown in the examples. In this disclosure, when a material contains multiple substances corresponding to each component, the amount of each component in the material means the total amount of the multiple substances present in the material, unless otherwise specified.

[0010] First Embodiment The first embodiment of the present disclosure is Contains a resin that melts or softens when heated, The resin member has protrusions on its surface, the protrusions having a diameter of 200 nm or less.

[0011] The resin member of this embodiment has protrusions on its surface, the protrusions having a diameter of 200 nm or less. By having protrusions on the surface that satisfy the above conditions, various functionalities are imparted to the surface of the resin member. For example, in the examples described below, it has been confirmed that a resin member having protrusions on its surface has an increased contact angle with water and thus has improved water repellency. Furthermore, the resin workpiece of the present embodiment contains a resin that melts or softens when heated, and therefore the resin workpiece of the present embodiment can be used in applications other than those of the cured product obtained by irradiation with active energy rays.

[0012] In the present disclosure, a "protrusion" refers to a relatively elevated region (convex portion) that is surrounded on all sides by a relatively depressed region (concave portion) on the surface of a resin member. The difference in height between the convex portion corresponding to the protrusion and the concave portion surrounding it (ie, the height from the base to the top of the protrusion) is not particularly limited and may be, for example, 50 nm or more. The shape of the protrusions is not particularly limited, and may be, for example, a columnar shape in which the difference between the diameter at the base and the diameter at the apex is small, or a tapered shape in which the diameter at the apex is smaller than the diameter at the base.

[0013] The diameter of the protrusions on the surface of the resin member is not particularly limited as long as it is 200 nm or less, and may be, for example, 150 nm or less, 100 nm or less, or 50 nm or less. When the diameter of the protrusions is 200 nm or less, the properties derived from the fine three-dimensional structure tend to be sufficiently exhibited on the surface of the resin workpiece. The lower limit of the diameter of the protrusions may be, for example, 10 nm or more, 15 nm or more, or 20 nm or more.

[0014] In the present disclosure, the "diameter of a protrusion" refers to the diameter at the top of the protrusion. More specifically, the diameter of a protrusion is defined as the minimum value of the distance between two parallel lines circumscribing the area corresponding to the top of the protrusion in an image of the surface of a resin member having the protrusion photographed with an electron microscope or the like.

[0015] The aspect ratio of the protrusions on the surface of the resin member is not particularly limited as long as it is 0.25 or more, and may be, for example, 0.35 or more, 0.50 or more, 0.75 or more, or 1.00 or more. When the aspect ratio of the protrusions is 0.25 or more, the properties derived from the fine three-dimensional structure tend to be sufficiently exhibited on the surface of the resin workpiece. The upper limit of the aspect ratio of the protrusions may be, for example, 10.0 or less, 5.0 or less, or 3.0 or less.

[0016] In the present disclosure, the "aspect ratio of a protrusion" is the value obtained by dividing the height of a protrusion by the diameter of the protrusion (height / diameter). The height of the protrusions may be, for example, 50 nm or more, 100 nm or more, or 150 nm or more.

[0017] When the resin member has a plurality of protrusions on its surface, it is preferable that the arithmetic mean value of the diameters of the plurality of protrusions present on the surface of the resin member satisfies the above-mentioned protrusion diameter condition, and it is preferable that the arithmetic mean value of the aspect ratios of the plurality of protrusions present on the surface of the resin member satisfies the above-mentioned protrusion aspect ratio condition.

[0018] When the number of protrusions on the surface of the resin member is extremely large, the arithmetic mean value of the diameters or aspect ratios of the protrusions may be the arithmetic mean value of the diameters or aspect ratios of protrusions randomly selected from the protrusions on the surface of the resin member. In this case, from the viewpoint of measurement accuracy, it is preferable that the number of protrusions randomly selected is 100 or more.

[0019] When the resin member has a plurality of protrusions on its surface, it is preferable that the variation in diameter of the plurality of protrusions present on the surface of the resin member is small. Specifically, among the multiple protrusions present on the surface of the resin member, the proportion of protrusions whose measured diameter D satisfies the following formula (1) is preferably 50% or more by number, more preferably 80% or more, even more preferably 90% or more, and even more preferably 100%. D in formula (1) av means the arithmetic mean value of the diameters of a plurality of protrusions present on the surface of the resin member. Formula (1): 0.8×D av ≦D≦1.2×D av

[0020] When the resin member has a plurality of protrusions on its surface, the resin member preferably has an area in which the center-to-center distance between the protrusions is 300 nm or less. When the resin member has a region in which the center-to-center distance between protrusions is 300 nm or less, the properties derived from the fine three-dimensional structure tend to be fully manifested on the surface of the resin member. The center-to-center distance of the protrusions may be, for example, 250 nm or less, 200 nm or less, or 150 nm or less. The center-to-center distance of the protrusions may be, for example, 10 nm or more, 15 nm or more, or 20 nm or more.

[0021] In the present disclosure, the "center-to-center distance of protrusions" refers to the distance between the centers of the regions corresponding to each of a pair of adjacent protrusions when observed from directly above.

[0022] The resin material has 100 protrusions per μm. 2 It is preferable to have a region in which the above is true. The resin material has 100 protrusions / μm 2 When the resin member has a region having the above range, the properties derived from the fine three-dimensional structure tend to be sufficiently exhibited on the surface of the resin member. The number of protrusions in the above region is, for example, 120 / μm 2 More than 150 pieces / μm 2 or more than 200 pieces / μm 2 It may be more than that. The number of protrusions in the above region is, for example, 1000 / μm 2 Below 800 pieces / μm 2 Below or 600 pieces / μm 2 It may be the following.

[0023] The resin member preferably has a region where the area occupancy of the protrusions is 50% or more. When the resin member has a region where the area occupancy rate of the protrusions is 50% or more, the properties derived from the fine three-dimensional structure tend to be fully manifested on the surface of the resin member. The area occupancy rate of the protrusions in the above region may be, for example, 60% or more, 70% or more, or 80% or more. The area occupancy rate of the protrusions in the above region may be, for example, 95% or less, 90% or less, or 85% or less.

[0024] In the present disclosure, the area occupancy rate of protrusions is a value obtained by, when observing an area of ​​a resin member having protrusions, dividing the area of ​​the area corresponding to the protrusions by the area of ​​the observed area. The area occupancy rate of the protrusions may be calculated by performing a process of binarizing an image of an area of ​​the resin member having protrusions into an area corresponding to the protrusions and an area not corresponding to the protrusions.

[0025] The resin member contains a resin that melts or softens when heated. The type of resin that melts or softens when heated is not particularly limited, and can be selected from known thermoplastic resins, thermoplastic elastomers, thermosetting resins, and thermosetting elastomers.

[0026] Thermoplastic resins include polyolefin (PO), polystyrene (PS), acrylonitrile / styrene resin (AS), acrylonitrile / butadiene / styrene resin (ABS), methacrylic resin (PMMA), polyvinyl chloride (PVC), polyamide (PA), polyacetal (POM), ultra-high molecular weight polyethylene (UHPE), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polymethylpentene (TPX), polycarbonate (PC), modified polyphenylene ether (PPE), ), polyphenylene sulfide (PPS), polyether ether ketone (PEEK), liquid crystal resin (LCP), polytetrafluoroethylene (PTFE), polyetherimide (PEI), polyarylate (PAR), polysulfone (PSF), polyethersulfone (PES), polyamideimide (PAI), polybutylene sulfide (PBS), polycyclohexylene dimethylene terephthalate (PCT), thermoplastic polyimide (TPI), polyphthalamide (PPA), polyimide (PI), etc.

[0027] Examples of the thermoplastic elastomer include styrene-based thermoplastic elastomers, polyester-based thermoplastic elastomers, urethane-based thermoplastic elastomers, and amide-based thermoplastic elastomers.

[0028] Examples of the thermosetting resin include phenol resin, urea resin, melamine resin, unsaturated polyester, alkyd resin, epoxy resin, and diallyl phthalate resin.

[0029] Thermosetting elastomers include natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene copolymer rubber (SBR), chloroprene rubber (CR), acrylonitrile-butadiene copolymer rubber (NBR), and other diene rubbers, butyl rubber (IIR), ethylene-propylene rubber (EPM), urethane rubber, and silicone rubber. Examples of suitable rubbers include non-diene rubbers such as diene rubber and acrylic rubber.

[0030] From the viewpoint of ease of forming protrusions on the surface of the resin member, the resin is preferably a thermoplastic resin or a thermoplastic elastomer, more preferably a thermoplastic resin, and further preferably a polyolefin.

[0031] From the viewpoint of forming protrusions with excellent alignment properties on the surface of a resin member, the resin is preferably a polyolefin containing at least one of a side chain having 3 or more carbon atoms or a siloxane bond. Examples of polyolefins containing a side chain having 3 or more carbon atoms include homopolymers of 4-methyl-1-pentene and copolymers of 4-methyl-1-pentene and an α-olefin other than 4-methyl-1-pentene. Examples of α-olefins other than 4-methyl-1-pentene include ethylene, propylene, 1-butene, 1-hexene, 3-methyl-1-butene, 3-methyl-1-pentene, 1-octene, 1-decene, 1-hexadecene, 1-heptadecene, and 1-octadecene.

[0032] The reason why protrusions with excellent alignment are formed when a polyolefin containing at least one of a side chain having three or more carbon atoms or a siloxane bond is used is presumably because, for example, when the protrusions are formed on the surface of a resin part using a mold, the protrusions have excellent releasability from the mold and are less likely to be destroyed.

[0033] The resin member may contain components other than resin, such as fillers such as glass fiber and inorganic powder, heat stabilizers, antioxidants, pigments, weather resistance agents, flame retardants, plasticizers, dispersants, lubricants, release agents, and antistatic agents.

[0034] When the resin member contains components other than resin, the proportion of resin in the entire resin member is preferably 50 mass % or more, more preferably 60 mass % or more, and even more preferably 70 mass % or more.

[0035] From the viewpoint of mass productivity, the resin member is preferably an injection-molded product made of a material containing a resin that melts or softens when heated (hereinafter, also referred to as a resin material).

[0036] <Second embodiment> The second embodiment of the present disclosure is Providing a template having pores with diameters of 200 nm or less; bringing a resin melted or softened by heating into contact with the mold; The method for producing a resin member includes the steps of:

[0037] According to the method of the present embodiment, a fine three-dimensional structure can be formed on the surface of a resin member that contains a resin that melts or softens when heated. The method of the present embodiment is more economical and versatile than a method of producing a resin workpiece by irradiating a curable composition with active energy rays.

[0038] The details and preferred aspects of the resin member produced by the method of this embodiment are similar to those of the resin member of the above-mentioned first embodiment. That is, the method of this embodiment may be a method for producing the resin member of the above-mentioned first embodiment.

[0039] The template prepared by the method of this embodiment is not particularly limited as long as it has pores with a diameter of 200 nm or less. Examples of templates having pores with diameters of 200 nm or less include those obtained by anodizing the surface of an aluminum-containing base material. Anodizing is a process in which a substrate containing aluminum as a positive electrode and a negative electrode are immersed in an acidic aqueous solution, and a direct current power source is connected between the electrodes to pass electricity through them, thereby forming a coating made of an oxide on the surface of the substrate. The coating formed by anodizing has highly regular pores.

[0040] By changing the conditions of the anodizing treatment, it is possible to control the diameter, depth, etc. of the holes formed in the surface of the aluminum-containing base material. Therefore, by using a mold obtained by anodizing the surface of the aluminum-containing base material, it is possible to manufacture a resin member having protrusions of desired dimensions on its surface.

[0041] In the method of the present embodiment, the resin that has been melted or softened by heating is brought into contact with the mold. By bringing the resin that has been melted or softened by heating into contact with the mold, the resin fills the holes in the mold. As a result, protrusions having a shape corresponding to the shape of the holes in the mold are formed on the surface of the resin member.

[0042] The method of contact is not particularly limited as long as the resin melted or softened by heating can enter the pores of the mold. From the viewpoint of accurately forming protrusions with a diameter of 200 nm or less on the surface of a resin member, an injection molding method is preferred, which allows the resin to be forced into holes in a mold while being subjected to high pressure. The injection molding method is also advantageous from the viewpoint of mass productivity.

[0043] After the resin in contact with the mold has solidified, the resin is released from the mold by any known method without any particular limitation. The surface of the mold that comes into contact with the resin may be treated to facilitate release of the resin from the mold. The above-mentioned treatment method includes a method of applying a compound such as a phosphonic acid compound, a silane compound, a carboxylic acid derivative, a fluorohydrocarbon, or a thiol derivative to the surface that is to come into contact with the resin of the mold. Among the above-mentioned compounds, a silane compound is preferable, and a silane compound having a fluoroalkyl group (a fluoroalkylsilane compound) is more preferable. Another example of such a treatment is to give the surface of the mold that comes into contact with the resin a texture (a process that creates minute irregularities on the surface). Examples of texture processes include chemical etching.

[0044] The resin used in the method of this embodiment can be selected without particular limitation from resins that melt or soften when heated and may be contained in the resin member of the above-mentioned first embodiment. When injection molding is employed in the method of this embodiment, the resin is preferably a thermoplastic resin or a thermoplastic elastomer, more preferably a thermoplastic resin, and further preferably a polyolefin.

[0045] From the viewpoint of forming protrusions with small dimensional variation on the surface of a resin member, the resin is preferably a polyolefin containing at least one of a side chain having three or more carbon atoms or a siloxane bond.

[0046] <Third embodiment> A third embodiment of the present disclosure is Including the resin member of the first embodiment, The resin product is selected from the group consisting of water-repellent materials, oil-repellent materials, anti-reflective materials, friction-reducing materials, adhesive materials (substrates for applying adhesives), heat-sealing materials, painting equipment, antibacterial materials, virus inactivation materials, anti-fungal materials, light-collecting materials, cell culture container materials, sound-absorbing materials, heat-dissipating materials, gas-adsorbing materials, and bioabsorbable materials.

[0047] The resin product of this embodiment can utilize various functions that are imparted by the protrusions formed on the surface of the resin member. The resin product of the present embodiment may be made of only the resin member of the first embodiment, or may be a combination of the resin member of the first embodiment with other members. As the other members, members made of materials such as resin, metal, ceramic, glass, and carbon can be used without any particular limitation. EXAMPLES

[0048] The present disclosure will be described in more detail below with reference to examples, but the present disclosure is not limited to these examples.

[0049] <Example 1> (1) Preparation of the mold A mold was prepared by anodizing the surface of an aluminum-containing substrate, which had an oxide film with pores about 100 nm in diameter and about 1200 nm in depth arranged with center-to-center spacing of about 100 nm.

[0050] (2) Preparation of resin parts Poly(4-methyl-1-pentene) (TPX-MX0020, Mitsui Chemicals, Inc.) was introduced as a resin that was melted by heating into the cavity of an injection molding die that used the above-mentioned mold as a part of the die. The resin was cooled in this state, and the solidified resin was removed from the die. Figure 1 shows an electron microscope image of the surface of the removed resin part that had been in contact with the mold. As shown in FIG. 1, an array of protrusions with diameters of 200 nm or less was observed on the surface of the resin member that had been in contact with the template.

[0051] (3) Contact angle measurement Ion-exchanged water (2 μL) was dropped onto the surface of the obtained resin member on which the protrusions were formed, and the contact angle was measured 1 minute after the drop. The measurement was performed under conditions of 24°C and 31% relative humidity. The contact angle calculated by the tangent method from the image of the water droplet taken with a digital camera was 122°. On the other hand, when the contact angle with water on the surface of a resin workpiece produced in the same manner as above except that no mold was used was measured, it was 102°. From the above results, it is understood that the water repellency of the resin member is increased by the protrusions formed on the surface.

[0052] (4) Gloss measurement The gloss of the surface of the resin member on which the protrusions were formed was measured by the following method, and the result was 48%. On the other hand, when the surface gloss of a resin workpiece produced in the same manner as above except that no mold was used was measured, it was found to be 54%. From the above results, it is understood that the glossiness of the resin member is hardly changed by the protrusions formed on the surface.

[0053] <Example 2> A resin part was produced in the same manner as in Example 1, except that a mixture of 10 parts by mass of a triblock polymer having a main chain composed of polyethylene and silicone (EXFORA, Mitsui Chemicals, Inc.) and 90 parts by mass of polypropylene (J105G, Prime Polymer Company) was used as the resin. FIG. 2 shows an electron microscope image of the surfaces of the resin parts that were in contact. As shown in FIG. 2, an array of protrusions with diameters of 200 nm or less was observed on the surface of the resin member that had been in contact with the mold.

[0054] Ion-exchanged water (2 μL) was dropped onto the surface of the obtained resin member on which the protrusions were formed, and the contact angle was measured 1 minute after the drop. The measurement was performed under conditions of 24°C and a relative humidity of 31%. The contact angle calculated by the tangent method from an image of the water droplet taken with a digital camera was 140°. On the other hand, when the contact angle with water on the surface of a resin workpiece produced in the same manner as above except that no mold was used was measured, it was 96°. From the above results, it is understood that the water repellency of the resin member is increased by the protrusions formed on the surface.

[0055] The gloss of the surface of the resulting resin member on which the protrusions were formed was measured in the same manner as in Example 1, and was found to be 27%. On the other hand, when the gloss of a resin workpiece produced in the same manner as above except that no mold was used was measured, it was found to be 47%. From the above results, it is understood that the glossiness of the resin member is reduced (the matteness is increased) due to the protrusions formed on the surface.

Claims

1. Contains a resin that melts or softens when heated, A resin member having protrusions on its surface, the protrusions having a diameter of 200 nm or less.

2. The resin member according to claim 1 , wherein the protrusions have an aspect ratio of 0.25 or more.

3. The resin member according to claim 1 , wherein the protrusions have a height of 50 nm or more.

4. The resin member according to claim 1 , further comprising a region in which the center-to-center distance between the protrusions is 300 nm or less.

5. The number of the protrusions is 100 / μm ２ The resin member according to claim 1 , further comprising a region in which the thickness is equal to or greater than the thickness of the resin member.

6. The resin member according to claim 1 , wherein the resin includes a polyolefin.

7. The resin member according to claim 6 , wherein the polyolefin contains at least one of a side chain having 3 or more carbon atoms and a siloxane bond.

8. The resin member according to claim 1 , which is an injection molded product.

9. Providing a template having holes with diameters of 200 nm or less; bringing a resin melted or softened by heating into contact with the mold; The method for producing a resin member includes the steps of:

10. The method for producing a resin member according to claim 9 , wherein the hole has an aspect ratio of 0.25 or more.

11. The method for producing a resin member according to claim 9 , wherein the contacting method is an injection molding method.

12. The method for producing a resin member according to claim 9 , wherein the mold is obtained by anodizing a surface of a base material containing aluminum.

13. The resin member according to any one of claims 1 to 8 is included, A resin product selected from the group consisting of water-repellent materials, oil-repellent materials, anti-reflective materials, friction-reducing materials, adhesive materials (substrates for applying adhesives), heat-sealing materials, painting equipment, antibacterial materials, virus inactivating materials, anti-fungal materials, light-collecting materials, cell culture container materials, sound-absorbing materials, heat-dissipating materials, gas-adsorbing materials, and bioabsorbable materials.

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