JP5453591B2 - Water and oil repellent antifouling member, method for producing the same, and article using the same - Google Patents

Description

The present invention relates to a water / oil repellent / antifouling member, a method for producing the same, and an article using the same, and more particularly, has high durability, can be produced at low cost, and has high safety to human bodies and the environment. The present invention relates to a water / oil repellent antifouling member, a method for producing the same, and an article using the same.

In recent years, with the improvement of living standards and the increase in hygiene awareness, there has been a demand for measures against contamination of articles around us, particularly articles made of plastic.

As a means for preventing contamination, there are a method of forming a film having a small surface energy on the surface of the member and a surface treatment method of reducing the surface energy of the surface of the member itself, but among them, a technology with less environmental impact during processing, In addition, there is a demand for a manufacturing technique that causes less environmental destruction when a product is discarded.

For example, in Patent Document 1, a film having a fluoroalkyl group and a siloxane bond is formed on the top surface of a float glass as a technique for forming a monomolecular film having low surface energy and resource saving on the surface of a member. There is disclosed a cooking device characterized in that glass is used as a window glass and the film surface is on the cooking side.

Patent Document 2 discloses a technique for antifouling treatment of the member surface itself using fluorine gas.

JP 10-137132 A JP-A-2005-290118

However, in the method described in Patent Document 1, when the base material that forms a film on the surface is a resin or the like that does not have an active hydrogen group on the surface, it is necessary to oxidize the surface in advance to introduce active hydrogen. Moreover, since a solvent is required at the time of film formation, it has the problem that environmental impact is large.
On the other hand, the method described in Patent Document 2 does not require a solvent at the time of film formation, but has a problem that the reaction requires a long time (several hours) and is therefore inefficient.

The present invention has been made in view of such circumstances, and provides a water- and oil-repellent antifouling member that can be manufactured at low cost and has a low environmental impact during processing and disposal, a method for manufacturing the same, and an article using the same. The purpose is to do.

A first aspect of the present invention, some or all of the hydrogen atoms have a one or a hydrocarbon group substituted with both a fluorine atom and a fluorocarbon group on the surface of the substrate, in the visible light region By providing a water and oil repellent and antifouling member that is transparent and has a surface roughness of 10 nm or more and 400 nm or less, the above-mentioned problems are solved.
Since the surface of the substrate has a hydrocarbon group in which some or all of the hydrogen atoms are substituted with either or both of fluorine atoms and fluorocarbon groups, the surface energy is reduced and the water and oil repellency is improved. At the same time, it is difficult to attach organic matter or the like which is a source of dirt, so that the antifouling property can also be improved.

In the water / oil repellent / antifouling member according to the first aspect of the present invention, the substrate may be a resin transparent in the visible light region .

In water-repellent, oil-repellent antifouling member according to the first aspect, the surface roughness is Ru der than 400nm or less 10 nm.
When the surface roughness of the substrate is 400 nm or less, which is the shortest wavelength of visible light, high water and oil repellency and antifouling properties can be imparted without impairing the transparency of the substrate even when the substrate is a transparent resin.

In the second aspect of the present invention, a gas atmosphere of a compound containing a fluorocarbon group is preliminarily treated in a visible light region in an oxygen gas atmosphere and a substrate having a hydrocarbon group on the surface is subjected to low-pressure plasma treatment. Among them, the above- mentioned problems are solved by providing a method for producing a water- and oil-repellent and antifouling member, characterized in that the substrate is subjected to low-pressure plasma treatment.
Compounds containing a fluorocarbon group is a plasma processing conditions, to generate fluorine radicals (· F) or · CF ₃ and the like fluorocarbon radicals. By replacing this with a hydrogen atom of a hydrocarbon group present on the surface of the substrate, a fluorocarbon group can be introduced into the surface of the substrate without using a solvent, and the surface energy of the substrate can be reduced.

In the method for producing a water / oil repellent / antifouling member according to the second aspect of the present invention, after the low-pressure plasma treatment of the substrate in an oxygen gas atmosphere in advance, The substrate is subjected to low-pressure plasma treatment in a gas atmosphere.
If the substrate is preliminarily subjected to low-pressure plasma treatment in an oxygen gas atmosphere and then the substrate is subjected to low-pressure plasma treatment in a gas atmosphere containing a fluorocarbon group, it is highly water-repellent and highly durable. An oil antifouling member can be provided efficiently.

In the method for producing a water / oil repellent / antifouling member according to the second aspect of the present invention, as the compound containing a fluorocarbon group, tetrafluoromethane (CF ₄ ), hexafluoroethane (C ₂ F ₆ ), It is preferable to use one or more of tetrafluoroethylene (C ₂ F ₄ ) and trifluoromethane (CHF ₃ ).
Since these compounds containing a fluorocarbon group are available at a relatively low cost, the manufacturing cost of the water / oil repellent / antifouling member can be reduced.

The third aspect of the present invention solves the above problem by providing an article using the water / oil repellent / antifouling member according to the first aspect of the present invention.

In the article according to the third aspect of the present invention, the water / oil repellent / antifouling member is any one of a building, an automobile, a ship, an aircraft, a train, an apparel product, a decorative product, and various daily necessities, or The member used may be sufficient.
These articles or members used for them are all used for articles that often come into contact with the human body, especially for buildings, automobiles, ships, aircraft, and trains in public places. There are many opportunities for people to touch. Accordingly, antifouling properties are strongly demanded, and the present invention can be suitably applied.

According to the present invention, there are provided a water / oil / oil repellent / antifouling component which can be produced at low cost and has a low environmental impact during processing and disposal, a method for producing the same, and an article using them. In addition, according to the method for producing a water / oil repellent / antifouling member of the present invention, water / oil / oil repellent can be provided only on the outermost surface of various substrates having a hydrocarbon group on the surface, with resource saving, energy saving and low cost. It is possible to impart a soiling function.

The water- and oil-repellent antifouling member and the article using the same according to the present invention have high antifouling property, durability, safety to human body and environment, and can exhibit antifouling property semipermanently.

It is explanatory drawing of the cross-sectional structure of the water repellent / oil repellent antifouling member which concerns on one embodiment of this invention. It is explanatory drawing of the manufacturing method of the water-repellent | oil-repellent | oil-repellent | antifouling | stain-resistant member, (a) and (b) are the group | bases before and after the low-pressure plasma processing in the gas atmosphere of the compound which has a fluorocarbon group, respectively. It is explanatory drawing which expanded the surface vicinity of material to the molecular level, and represented typically.

Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.

The water / oil repellent / antifouling member 10 according to one embodiment of the present invention is a hydrocarbon group 11 (in which a part or all of hydrogen atoms are substituted with either or both of a fluorine atom and a fluorocarbon group). In FIG. 1, the surface of the acrylic substrate 12, which is an example of a substrate, is schematically shaded). As shown in FIG. 2A, the acrylic substrate 12 is covered with hydrocarbon groups 13 on the surface. On the surface of the water / oil repellent / antifouling member 10 after the low-pressure plasma treatment, as shown in FIG. 2B, the hydrogen atoms of the hydrocarbon groups 13 covering the surface of the acrylic substrate 12 before the low-pressure plasma treatment. A part is substituted with a trifluoromethyl group 14 which is an example of a fluorocarbon group.

The water / oil repellent / antifouling member 10 is produced by subjecting the acrylic substrate 12 to low-pressure plasma treatment in a gas atmosphere of a compound containing a fluorocarbon group.
When plasma is generated by high frequency discharge in a gas atmosphere of a compound containing a fluorocarbon group, a fluorocarbon radical such as a fluorine radical (· F) or a trifluoromethyl radical (· CF ₃ ) is generated. These radicals substitute the hydrogen atom of the hydrocarbon group on the surface of the acrylic substrate 12 with the trifluoromethyl group 14 (FIG. 2B). Alternatively, when a gas of a compound having an unsaturated bond such as tetrafluoroethylene is used, a perfluoroalkyl group having a large carbon number can also be generated by plasma polymerization.

For the low-pressure plasma treatment, any plasma treatment apparatus that can be used for plasma surface treatment or low-temperature ashing can be used. Specific examples of the form of the chamber include a flow tube type, a bell jar type, etc., and as a form of the electrode for discharge, a parallel plate type, a coaxial cylindrical type, a curved counter plate type such as a cylinder, a sphere, etc. Examples include a hyperboloid opposed flat plate type and a plurality of fine wire opposed flat plate types. The high frequency current can be applied by either a capacitive coupling method or an induction method using an external electrode. The output of the high-frequency power source is appropriately adjusted depending on the material and size of the base material, the type of compound containing a fluorocarbon group used, the type and volume fraction of the added gas, the volume and pressure of the chamber, etc. For example, 10 to 250 W.

Examples of the compound containing a fluorocarbon group that has been confirmed to be usable include CF ₄ , C ₂ F ₆ , C ₂ F ₄ , and CHF ₃ . In principle, even a compound that contains a CF ₃ group and is liquid at normal temperature and pressure can be used as long as it can be gasified under low-pressure plasma processing conditions. At this time, if a trace amount (0.1 to 5% by volume) of Ar, He or the like is mixed, there is an effect of stabilizing the discharge.

Further, if a small amount of oxygen (0.1 to 15% by volume) is contained, the resin surface is replaced with a CF ₃ group while oxidizing the resin surface, which has an effect of increasing the processing efficiency. Alternatively, low-pressure plasma treatment may be performed in a gas atmosphere of a compound containing a fluorocarbon group after performing low-pressure plasma treatment in an oxygen gas atmosphere in advance and performing surface oxidation etching.

Further, in the present embodiment, the acrylic substrate 12 made of acrylic resin is described as an example of the substrate, but as the substrate, any substrate having a resin containing a hydrocarbon group on the surface can be used. Even things can be used. Specific examples of the resin include polyurethane, polyester, polyethylene, polyphenylene sulfide, polyethylene terephthalate, polyethylene naphthalate, polyvinylidene chloride, polyvinyl chloride, polyolefin, polycarbonate, polyvinyl acetate, polystyrene, polysulfone, polytrimethylene terephthalate, poly Lactic acid, polyvinyl alcohol, polyvinyl pyrrolidone, polybutylene terephthalate, polybutylene naphthalate, polyvinylidene fluoride, polypropylene, polymer alloy, polymethylpentene, ionomer resin, acrylic resin, acetyl cellulose, alkyd resin, AS resin, liquid crystal polymer, ethylene propylene Examples include rubber, ABS resin, epoxy resin, urea resin, and other engineering plastics. It is. In addition to the resin, any material containing a hydrocarbon group can be used as the base material. Specific examples of the substrate other than the resin include natural and synthetic leather, natural and synthetic fibers (cotton, hemp, silk, wool, nylon, acrylic fiber, polyester, etc.), woody materials, paper, and the like. These materials may be used at least near the surface, and other portions may be made of a material that does not contain a hydrocarbon group such as metal or ceramics.

The surface roughness of the water / oil repellent / antifouling member 10 is 10 nm or more and 900 μm or less. The shape of the irregularities on the surface of the water / oil repellent / antifouling member 10 is not particularly limited as long as it does not impair the optical properties of the acrylic substrate 12 due to diffraction or irregular reflection of incident light. The shape may be irregular. In general, when the surface roughness is within the above range, the hydrophobicity of the surface after the low-pressure plasma treatment can be further improved without deteriorating the surface characteristics of the acrylic substrate 12. The surface roughness of the acrylic substrate 12 is preferably 400 nm or less, which is the shortest wavelength of visible light, more preferably 360 nm or less, and even more preferably 300 nm or less. If the surface roughness is within the above range, the optical properties of visible light such as transparency of the acrylic substrate 12 are not impaired. The surface roughness can be measured using any known method such as a surface roughness meter or a three-dimensional measuring instrument. Further, the size of the unevenness can be measured by image analysis using a stereoscopic microscope or an electron micrograph.

As a method for roughening the surface of the acrylic substrate 12 so as to have a surface roughness and irregularity in the above-mentioned range, chemical treatment with sandblasting, mechanical polishing, chromic acid mixture, phosphoric acid, alkali, etc. However, when the low-pressure plasma treatment is performed in an atmosphere containing oxygen gas, a surface having a desired surface roughness and unevenness can be obtained. The plasma processing conditions may be adjusted as appropriate.

As an article in which the water / oil repellent / antifouling member 10 is used, any of a building, an automobile, a ship, an aircraft, a train, an apparel product, a decorative product, and various daily necessities, or a member used for them can be cited. . Specific examples of articles are shown below.

(A) Examples of building materials :
Outer wall materials include wood (including processed wood), plastic materials (roof materials such as carports, rain gutters, etc.). Interior materials include wood (including processed wood), plastic materials, paper, and fibers.

(B) Examples of transportation parts such as automobiles, ships, aircraft and trains :
(1) ABS resin: lamp cover, instrument panel, interior parts, motorcycle protector, (2) Cellulose plastic: automotive mark, handle, (3) FRP (fiber reinforced resin): outer bumper, engine cover, 4) Phenol resin: brake, (5) Polyacetal: wiper gear, gas valve, carburetor parts, (6) Polyamide: Radiator fan, (7) Polyarylate: Direction indicator lens, instrument panel lens, relay housing, (8) Polybutylene Terephthalate (PBT): rear end, front fender, (9) polyamino bismaleimide: engine parts, gear box, wheel, suspension drive system, (10) methacrylic resin: lamp cover lens, instrument panel and cover, center mark, 1) Polypropylene: Bumper, (12) Polyphenylene oxide: Radiator grille, wheel cap, (13) Polyurethane: Bumper, fender, instrument panel, fan, (14) Unsaturated polyester resin: Body, fuel tank, heater housing, instrument Board.

(C) Examples of apparel products :
Also includes general natural fiber products, chemical fibers, synthetic fiber products, fur products, leather products, and paper products. Specifically, clothing, hats, ties, shoes, bags, umbrellas, raincoats, sports clothing, wall cloths, curtains, jutans, furniture, vehicle interiors, sheets, sanitary products, paper diapers, bedding, sheets, Fishing net etc.

(D) Examples of ornaments :
A resin or leather member used for watches, eyeglass frames, rings, bracelets, brooches, tie pins, earrings, necklaces, and the like.

(E) Examples of daily necessities :
(1) Paper products such as gravure paper, water and oil repellent paper, poster paper, high-grade brochure paper, (2) Television, radio, tape recorder, audio, CD, refrigerators, freezers, air conditioners, juicers, mixers for refrigeration related equipment , Fan blades, lighting fixtures, dials, permanent hair dryers, (3) skis, fishing rods, pole vaulting poles, boats, yachts, jet skis, surfboards, golf balls, bowling balls, fishing lines, fishnets , Sports equipment such as fishing floats, (4) fountain pens, ballpoint pens, sharp pencils, brush holders, binders, desks, chairs, bookshelves, racks, telephone stands, rulers, drafting tools, computers, mobile phones and other stationery and office supplies (5) Violin, viola, cello, contrabass, guitar, mandolin, piano, electronic organ Synthesizer, body or parts of the instrument and peripherals metronome etc., (6) a microphone, a speaker, earphone, housing and parts of audio equipment such as PA equipment.

Examples carried out for confirming the features and effects of the present invention will be described below.
Example 1: Production of a water / oil repellent / antifouling member having a transparent acrylic resin substrate as a base material First, after the transparent acrylic resin substrate as a base material was washed with ethanol, the conditions shown in Table 1 (Condition 1) were satisfied. Then, low-pressure plasma treatment (O ₂ plasma treatment) in an oxygen gas atmosphere was performed. Next, plasma treatment was performed in a tetrafluoromethane (CF ₄ ) atmosphere containing oxygen under the conditions shown in Table 2 (Condition 2). In Tables 1 and 2, sccm used as a unit of flow rate is a non-SI unit, and 1 sccm = 1.69 × 10 ⁻⁴ Pa · m ³ / sec.

The water droplet contact angle of the water / oil repellent / antifouling member thus obtained was measured. The measurement was performed at five different points (I to V) on the same sample. The measurement results are as shown in Table 3 below. In Table 3, “CA” means a contact angle, and “Avg.” And “SD” mean an average value and a standard deviation, respectively. The water droplet contact angle of the acrylic resin substrate before treatment was 75.0 degrees.

A significant increase in water droplet contact angle was observed for all samples. This is because, as shown in FIG. 2B, the hydrocarbon group on the surface of the acrylic resin substrate reacts with the .CF ₃ radical generated in the plasma, and the hydrogen atom is replaced with the —CF ₃ group. It is thought that the surface water repellency was improved by bonding a large number of CF ₃ groups.

Here, the O ₂ plasma treatment has an action of cleaning the surface of the acrylic resin substrate and an action of roughening the surface of the member, and the surface roughness can be controlled by arbitrarily controlling the power of the high frequency power source and the treatment time. Can be controlled within a range of several nanometers to several hundred microns, and the final water droplet contact angle can be controlled to about 165 to 100 degrees. In particular, if the water droplet contact angle was controlled to be 150 degrees or more, a high-performance oil-repellent and antifouling member with extremely low surface energy could be produced. Further, when the surface roughness was set to be equal to or less than the wavelength of visible light (for example, 400 nm), the transparency of the acrylic resin substrate used as the base material was not impaired.

In addition to CF ₄ , compounds containing CF ₂ groups or CF ₃ groups such as C ₂ F ₆ , C ₂ F ₄ , and CHF ₃ could be used similarly.

The materials that can be used are of any material that contains hydrocarbon groups, and in addition to artificial materials such as synthetic resin, synthetic leather, and synthetic fibers, it also applies to natural materials such as woody materials, paper, and wool. I was able to handle it. An example in which the same treatment was performed on PET as another resin material is shown in Example 2.

Example 2: Production of water- and oil-repellent and antifouling member based on a transparent polyethylene terephthalate resin substrate As in Example 1, first, a transparent PET (polyethylene terephthalate) resin substrate was washed with ethanol, and then in Table 1. Under the conditions (condition 1) shown, O ₂ plasma treatment was performed. Next, conditions similar to those shown in Table 2 were used except that hexafluoroethane (C ₂ F ₆ ) was used as the compound containing a fluorocarbon group, the power of the high-frequency power source was 250 W, and the treatment time was 5 minutes. Then, low-pressure plasma treatment was performed. Then, when the contact angle was measured, the water droplet contact angle of the sample was 147 degrees.
In addition, even when other compounds containing a fluorocarbon group were used, it was confirmed that the same effect was obtained if a CF ₂ group or a CF ₃ group was included.

The method for producing a water / oil repellent / antifouling member according to the present invention is applicable to any material as long as a member containing a hydrocarbon group is used on the surface. Specifically, it can be used for buildings around us, automobiles, ships, aircraft, trains, apparel products, ornaments, daily goods, and ornaments, and can impart water and oil repellency and antifouling properties to the surface. . Thereby, since adhesion of organic substances to the surface of the water / oil repellent / antifouling member is suppressed, the propagation of harmful microorganisms such as bacteria and fungi can be suppressed, and the surface can be kept clean.

10: Water- and oil-repellent antifouling member 11: Hydrocarbon group in which a part or all of hydrogen atoms are substituted with one or both of fluorine atoms and fluorocarbon groups 12: Acrylic base material 13: Carbonization Hydrogen group 14: trifluoromethyl group

Claims (6)

Some or all of the hydrogen atoms have a one or a hydrocarbon group substituted with both a fluorine atom and a fluorocarbon group on the surface of the substrate, transparent in the visible light region, and the surface roughness 10nm A water / oil / oil repellent and antifouling member having a thickness of 400 nm or less . The water / oil repellent / antifouling member according to claim 1, wherein the substrate is a resin transparent in a visible light region . Advance, in an oxygen gas atmosphere, transparent in the visible light range, after a substrate having a hydrocarbon group on the surface and low pressure plasma treatment, in a gas atmosphere of a compound containing a fluorocarbon group, a low pressure said substrate A method for producing a water- and oil-repellent and antifouling member, characterized by plasma treatment. As the compound containing the fluorocarbon _{group, CF 4, C 2 F 6} , C 2 F 4, and water-repellent, oil-repellent antifouling according to claim 3, which comprises using one or more of CHF ₃ Manufacturing method of member. Article with claim 1 or 2 water-repellent, oil-repellent antifouling member according. The water / oil repellent / antifouling member is any one of a building, an automobile, a ship, an aircraft, a train, an apparel product, a decorative product, and various daily necessities, or a member used for them. Item 5. The method for producing a water- and oil-repellent antifouling member according to Item 3 or 4 .

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