JP2002309018A - Method for modifying surface of fluororesin formed product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for modifying the surface of a fluororesin formed product, which is used for imparting high adhesive durability to the surface of the fluororesin formed product, especially for imparting high adhesive durability to rubbers, in particular, high conductive silicone rubbers. SOLUTION: This method for modifying the surface of the fluororesin formed product is characterized by adhering a solution, dispersion or suspension containing an organic silicon compound, an ultraviolet light-absorbing compound and a fluorosurfactant to the surface of the fluororesin formed product and then irradiating the adhered surface with an ultraviolet laser beam.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a modification of the surface of a fluororesin molded article for imparting high adhesion durability to the surface of the fluororesin molded article, particularly to rubber, especially high-conductivity silicone rubber. On quality law.

[0002]

2. Description of the Related Art Compared with other resins, fluororesins are excellent in water repellency, oil repellency, slidability, antifouling properties, heat resistance, chemical resistance, electrical properties, and the like. However, due to the inert surface, not only is it difficult to apply an adhesive or a paint, but also it is difficult to form a composite with other materials.

Various methods have been proposed as solutions to such a problem. For example, (i) a method of treating with a complex compound solution prepared from a tetrahydrofuran solution of sodium metal and naphthalene [Nelson (ERNelson)
Ind. Eng. Chem., 50, 329 (1958).
), (Ii) Method using glow discharge [see Kakuda et al., Industrial Materials, Vol. 29 (No. 2), p. 105 (1981)], (iii) High-frequency sputter etching under low pressure (See JP-B-53-22108).
(iv) A method of irradiating a laser beam in a special gas atmosphere such as B (CH ₃ ) ₃ or Al (CH ₃ ) ₃
196834), (v) a method of directly irradiating excimer laser light (see Japanese Patent Publication No. 3-57143),
(vi) Method of processing by low-temperature plasma sputter etching (Japanese Patent Publication No. 58-21928, Japanese Patent Application Laid-Open No. 2-1274)
No. 42 and Japanese Patent Publication No. 3-58375) and (vii) a method of kneading a light-absorbing substance in advance and then irradiating an ultraviolet laser beam (see JP-A-5-125208).
And the like.

[0004] However, these reforming methods have the following problems. In the case of the method (i), there is a danger of ignition during the treatment, and the treatment liquid is unstable. Therefore, not only is there a problem in work hygiene, but also when the modified surface is exposed to sunlight or high temperature. There is a disadvantage that the adhesiveness and the like are significantly reduced. Method (ii) has a disadvantage that the surface modification effect is significantly lower than that of a fluorine-free polymer such as polyethylene. In the case of the method (iii), the processing speed is low, and not only the etched resin component adheres to the inside of the expensive and large-sized vacuum processing apparatus, but also the easily-frayable unevenness formed on the resin surface has a low flow rate. However, there is a problem that sufficient adhesiveness, paintability, and the like are not brought about to a water-soluble adhesive or paint. In the case of the method (iv), there is a problem that the processing speed is slow, and a highly toxic gas and an expensive and large-sized vacuum processing apparatus are required. Method
In the case of (v), there is a problem that the adhesiveness and wettability of the fluororesin surface cannot be sufficiently improved. Further, method (vi)
In the case of (1), since the chemical composition of the treated surface does not change, it is difficult to obtain a high adhesive strength. It is necessary to perform a long-time treatment under the above-mentioned treatment conditions, which is insufficient as an industrial treatment technique. Furthermore, in the case of the method (vii), there is a drawback that the method cannot be applied to the surface modification of a fluororesin molded body containing no light-absorbing substance.

[0005] The applicants of the present application have previously solved the problems of the above-mentioned method of modifying the surface of a fluororesin, and have provided a method capable of imparting high adhesiveness and wettability to the surface of a fluororesin in general. No. 2983438). However, a fluororesin molded body whose surface is modified by this method is mixed with a rubber material (for example, silicone) containing various additives (for example, a conductivity-imparting agent, a vulcanizing agent, a vulcanization aid, and a softening agent). Rubber, butadiene rubber, styrene rubber, chloroprene rubber, ethylene propylene rubber, natural rubber, etc.), especially conductive silicone rubber containing additives such as conductive carbon black, or thermally conductive silicone highly filled with silica / alumina It has been found that there is a problem that the bonding durability is poor when bonded with rubber or the like.

[0006] This problem is caused, for example, by various rollers used in electronic copiers and laser beam printers, etc.
That is, various rollers (for example, a charging roller, a developing roller, a transfer roller, a fixing roller, and the like) having a structure in which the coating layer of a metal cylindrical core body whose outer peripheral surface is coated with a rubber material is further covered with a fluororesin tube. Pressure roller, etc.).

[0007]

SUMMARY OF THE INVENTION The present invention solves the above technical problems and provides a high adhesive durability, especially a high adhesive durability to rubber, especially conductive silicone rubber and heat conductive silicone rubber. It is intended to provide a method that can be applied to the resin surface.

[0008]

That is, the present invention is to provide a solution, dispersion or suspension containing an organosilicon compound, a UV-absorbing compound and a fluorine-based surfactant on the surface of a fluororesin molded article, The present invention relates to a method for modifying the surface of a fluororesin molded body, which comprises irradiating an ultraviolet laser beam to the adhered surface.

The fluororesin molded article to which the present invention is applied is a molded article produced from a fluorine-containing organic polymer compound. As the base resin of the molded article, polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkoxyethylene copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer
(FEP), tetrafluoroethylene-hexafluoropropylene-perfluoroalkoxyethylene terpolymer (EPE), tetrafluoroethylene-ethylene copolymer (ETFE), polychlorotrifluoroethylene (PC
TFE), trifluorochloroethylene-ethylene copolymer (ECTFE), polyvinylidene fluoride (PVDF),
Polyvinyl fluoride (PVF), tetrafluoroethylene-
Perfluoromethoxyethylene copolymer (MFA), vinylidene fluoride-hexafluoropropylene copolymer, tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride terpolymer (THV), tetrafluoroethylene-propylene copolymer , Daiel Thermoplastic (Daikin Industries), Central Soft (Central Glass), Teflon AF (Dupont), Cytop (Asahi Glass), Dyneon HTE (3M), and a mixture of any two or more of these Resin is exemplified. Further, silica, alumina, silicon carbide, silicon nitride or the like may be appropriately added for the purpose of improving abrasion, and carbon black or the like may be appropriately added for the purpose of imparting electric conductivity. The specific form of the fluororesin molded article to be treated according to the present invention is not particularly limited, but examples include sheets, films, tubes, pipes, porous membranes, and molded articles having any other shapes.

As the organosilicon compound, a known compound may be appropriately used.
(Triphenylsilyl) acetylene, phenylsilane,
Examples include tetraphenoxysilane, triphenylsilane, tribenzylsilane, allyltriphenylsilane, triphenylvinylsilane, phenyltriethoxysilane, and the like. If desired, two or more of these organosilicon compounds may be used in combination.

The UV-absorbing compound may be any known one itself, and is not particularly limited. However, aromatic UV-absorbing compounds such as aromatic hydrocarbons, aromatic carboxylic acids and the like Salts, aromatic aldehydes, aromatic alcohols, aromatic amines and salts thereof, aromatic sulfonic acids and salts thereof, phenols and the like are preferred. The following are examples of this type of aromatic ultraviolet absorbing compound.

Naphthalene, phenanthrene, anthracene, naphthacene, pyrene, perylene, fluorenone, fluoranthene, 9-acetylanthracene, 9-methylanthracene, anthraquinonecarboxylic acid, anthracene
-9-Methanol, biphenyl, sodium benzoate, phthalic acid, benzaldehyde, benzyl alcohol, phenylethanol, benzenesulfonic acid, 2-naphthalenesulfonic acid, sodium anthraquinone-2-sulfonate, phenol, cresol, 2,4-dihydroxybenzophenone 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 4-dodecyloxy-2-hydroxybenzophenone, 2-hydroxy-4-octadecyloxybenzophenone, 2,2′-dihydroxy-4 -Methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxy-5
Sulfobenzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2'-hydroxy-
4-chlorobenzophenone, 2 (2'-hydroxy-5
(Methoxyphenyl) benzotriazole, 2 (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) benzotriazole, 2 (2′-hydroxy-3′-t-butyl-5 ′
-Methylphenyl) benzotriazole, phenyl salicylate, p-octylphenyl salicylate, p salicylic acid
-T-butylphenyl, carboxyphenyl salicylate, strontium salicylate, methyl salicylate, dodecyl salicylate, resorcinol monobenzoate,
2-ethylhexyl-2-cyano-3,3-diphenyl acrylate, ethyl-2-cyano-3,3-diphenyl acrylate, Ni-bisoctylphenyl sulfide, [2,2′-thiobis (4-t-octylphenolato) )]
-N-butylamine-Ni.

As the fluorine-based surfactant used together with the above-mentioned organosilicon compound and ultraviolet-absorbing compound, a surfactant known per se having a fluorocarbon chain as a hydrophobic group may be appropriately used. The following surfactants are exemplified as this type of fluorine-based surfactant. (1) Anionic fluorinated surfactant R _f COOM R _f SO ₂ N (R) ₂ CH ₂ COOM R _f CONRYOSO ₃ M R _f SO ₂ NRYOSO ₃ M R _f SO ₃ M R _f CH ₂ O (CH ₂ ) ₂ SO ₃ M

Embedded image

Embedded image

Embedded image In the above formula, R _f and R _f ′ represent a fluoroalkyl group, R represents a hydrogen atom or a lower alkyl group, Y represents a lower alkylene group, M represents a hydrogen atom, -N
H _{3 represents} an alkali metal atom or an alkaline earth metal atom.

[0014] (2) a cationic fluorocarbon surfactant _{R f CONHYN (R) (R} ') · HX R f SO 2 NHYN (R) (R') · HX

Embedded image

Embedded image In the above formula, R _f , R and Y are as defined above, R ′ represents a hydrogen atom or a lower alkyl group, and HX
Represents an acid, and X represents a halogen atom or an acid radical.

(3) Amphoteric fluorinated surfactant

Embedded image

Embedded image In the above formula, R _f , R and Y are as defined above.

(4) Nonionic fluorinated surfactant R _f OH

Embedded image

Embedded image In the above formula, R _f and R are as defined above,
n shows the number of 1-30. Note that two or more of the above-mentioned fluorine-based surfactants may be used in combination as needed.

Suitable commercially available fluorine-based surfactants include “Surflon S-” manufactured by Seimi Chemical Co., Ltd.
111 "(perfluoroalkyl carboxylate)," Surflon S-112 "(perfluoroalkyl phosphate)," Surflon S-113 "(perfluoroalkyl carboxylate)," Surflon S-121 "(perfluoroalkyl Alkyltrimethylammonium salt), "Surflon S-1
31 ”(perfluoroalkyl betaine),“ Surflon S
-132 "(perfluoroalkyl betaine)" Surflon S-141 "(perfluoroalkylamine oxide)," Surflon S-145 "(perfluoroalkylethylene oxide adduct)," Surflon S-381 "
(Perfluoroalkyl-containing oligomer), "Surflon S-383" (Perfluoroalkyl-containing oligomer), "Surflon S-393" (Perfluoroalkyl-containing oligomer), "Surflon SC-101" (Perfluoroalkyl-containing oligomer), "Surflon S
“C-105” (perfluoroalkyl-containing oligomer), “Surflon KH-40” (perfluoroalkyl ethylene oxide adduct) and “Surflon SA-
100 "(perfluoroalkyl-containing special combination product) and the like.

Further, other suitable commercially available fluorine-based surfactants include "Fluorad FC-430" (fluorinated alkyl ester) and "Fluorad FC-431" (fluorinated alkyl ester) manufactured by Sumitomo 3M Limited. And “F-Top EF-102” (perfluorosulfonate), “F-Top EF-103” (perfluorosulfonate), “F-Top EF-104” (perfluorosulfone) manufactured by Mitsubishi Materials Corporation Acid salt), "EFTOP EF-122" (perfluoroalkylethylene oxide adduct), "EFTOP E
F-351 "(fluorinated alkyl ester)," F-Top EF-352 "(fluorinated alkyl ester),
Examples include “F-Top EF-801” (fluorinated alkyl ester), “F-Top EF-802” (fluorinated alkyl ester), and “F-Top EF-601” (fluorinated alkyl ester).

The above-mentioned organosilicon compound, ultraviolet-absorbing compound and fluorine-containing surfactant are used in a solution containing water or a water-soluble organic solvent as a solvent from the viewpoint of the efficiency of modification of the surface of the fluororesin molded article and workability. , As a dispersion or suspension. As a solvent for the solution or the like, a mixture of water and a water-soluble organic solvent, for example, a lower alcohol (eg, methanol, ethanol, isopropanol, butanol, etc.) may be used. When used as an aqueous solution, a water-soluble organic solvent, for example, a lower alcohol such as isopropanol may be appropriately blended to increase the solubility of the organosilicon compound, the ultraviolet absorbing compound and the fluorine-based surfactant. .

The concentration of a solution of an organosilicon compound in water and / or a water-soluble organic solvent as a solvent depends on the type of the compound, the solubility in water and the like, the type of fluororesin to be treated, and the coexisting ultraviolet absorbing compound. It depends on the type and concentration of the fluorinated surfactant and is not particularly limited, but is generally 0.05 to 10% by weight, preferably 0.1 to 10% by weight.
1 to 5% by weight.

The concentration of the solution or the like of the ultraviolet-absorbing compound, the type of the compound and the solubility in water, the type of the fluororesin to be treated, the type and the concentration of the coexisting organosilicon compound and the fluorine-based surfactant, and the like. Although not particularly limited, it is generally 0.05 to 10% by weight,
Preferably it is 0.1 to 5% by weight.

Further, the concentration of the above-mentioned fluorine-based surfactant in an aqueous solution or the like may be any concentration at which the above-mentioned organosilicon compound and ultraviolet-absorbing compound are uniformly and uniformly present on the surface of the fluororesin molded article. Although not particularly limited, it is generally 0.05 to 2% by weight, preferably 0.5 to 2% by weight.
1 to 1% by weight.

The method for causing the aqueous solution of the above-mentioned organosilicon compound, ultraviolet absorbing compound and fluorine-containing surfactant to be present on the surface of the fluororesin molded article may be any of a coating method, a spraying method, a dipping method and the like. Good. After the aqueous solution or the like is present on the surface of the fluororesin molded body, a drying treatment may be performed before the irradiation with the ultraviolet laser beam. For the drying treatment, natural drying is sufficient.
It may be performed at 150 ° C. forcibly. Due to the action of the fluorinated surfactant, the organosilicon compound and the ultraviolet absorbing compound are uniformly present at a sufficient concentration on the surface of the fluororesin molding.

In the present invention, the surface of the molded article is irradiated with an ultraviolet laser beam under the conditions in which the above-mentioned organosilicon compound, ultraviolet-absorbing compound and fluorine-containing surfactant are present on the surface of the molded article. As the ultraviolet laser light, those having a wavelength of 400 nm or less are desirable, and argon laser light, krypton ion laser light,
d: YAG laser, _{N 2} laser, but dye laser light and excimer laser light, and the like, in particular, excimer laser light 193~308nm are preferred. In particular, KrF excimer laser light (wavelength: 248 nm), ArF excimer laser light (wavelength: 193 nm), and XeCl excimer laser light (308 nm) that can stably obtain high output for a long time are preferable. Excimer laser light irradiation is usually performed at room temperature and in the air, but may be performed in an oxygen atmosphere. The irradiation conditions of the excimer laser beam depend on the type of the fluororesin and the desired degree of surface modification, but the general irradiation conditions are as follows. Fluence: about 20 mJ / cm ² / pulse or more Incident energy: about 0.1 J / cm ² or more Number of shots: about 100 or less

Particularly preferred KrF excimer laser light, Ar
Irradiation conditions commonly used for the F excimer laser beam and the XeCl excimer laser beam are as follows. KrF fluence: 30 to 500 mJ / cm ² / pulse Incident energy: 0.2 to 2.0 J / cm ² Number of shots: 1 to 20 ArF fluence: 20 to 150 mJ / cm ² / pulse Incident energy: 0.1 to 1. 0 J / cm ² shot number: 1 to 20 XeCl fluence: 100 to 600 mJ / cm ² / pulse Incident energy: 0.1 to 2.0 J / cm ² shot number: 1 to 20

[0026]

The present invention will be described below with reference to examples.Example 1 In a 1% by weight aqueous solution of anthraquinone carboxylic acid, add
Freon S-132 ”(commercially available from Seimi Chemical Co., Ltd.)
Product; perfluoroalkyl betaine) at a concentration of 1% by weight
After addition, (triphenylsilyl) acetylene is added in 1
Pretreatment liquid is prepared by dispersing at the concentration of wt%
did. Applicator (Yashimitsu Seiki Co., Ltd. “YA
The pretreatment liquid is made of PFA using a "type applicator").
Apply on the surface of film (thickness: 100μm)
Kr.
Irradiated with F excimer laser light (irradiation amount: 0.6 J /
cm ²). Silicone rubber of the resulting surface-modified film
The following test evaluated the adhesive durability to the adhesive.Adhesion durability test Test film (150mm × 150mm × 100μm)
And aluminum plate (120mm × 120mm × 1m
m) with one-component addition type silicone rubber (volume resistivity: 1 ×
10³Ω · cm) and laminate this
Heating at 120 ° C for 30 minutes under load condition
Therefore, an adhesion test piece was prepared. The obtained adhesive test piece was
The adhesive test piece was left in a constant temperature bath at
When the film is removed from the water bath and peeled,
Check if the rubber adheres to the film and peels off
To evaluate the adhesive durability. Prepared in Example 1
Test film shows good adhesion after 2000 hours
Was.

Comparative Example 1 A test film prepared in the same manner as in Example 1 except that (triphenylsilyl) acetylene was not dispersed in the pretreatment liquid was subjected to an adhesion durability test.
After 0 hour, the silicone rubber showed no adhesion and peeling.

Example 2 To a 1% by weight ethanol solution of fluorene was added “Fluorad FC-430” (commercially available from Sumitomo 3M Limited; fluorinated alkyl ester) at a concentration of 1% by weight. A pretreatment solution was prepared by adding at a concentration of% by weight. The pretreatment liquid is applied to the surface of a PFA film (thickness: 100 μm) using an applicator (“Y-type applicator” manufactured by Yoshimitsu Seiki Co., Ltd.) (applied thickness: 25 μm), and naturally dried for about 30 minutes. The coated film was irradiated with KrF excimer laser light (irradiation amount: 0.4 J / cm ² ). The obtained surface-modified film was treated with a one-component addition type silicone rubber (thermal conductivity: 4.2 W).
/ M · ° C.), the adhesive durability test described above showed good adhesion even after 2000 hours.

Comparative Example 2 A test film prepared in the same manner as in Example 2 except that phenylsilane was not added to the pretreatment liquid was subjected to an adhesion durability test. No longer show.

Example 3 1% by weight of "Fluorard FC-430" (commercially available from Sumitomo 3M; fluorinated alkyl ester) was added to a 1% by weight ethanol solution of 9-acetylanthracene.
, A phenylsilane was added at a concentration of 1% by weight to prepare a pretreatment liquid. The pretreatment liquid was applied to the surface of a PTFE film (thickness: 100 μm) using an applicator (“YA type applicator” manufactured by Yoshimitsu Seiki Co., Ltd.) (coating thickness: 25 μm).
m), the coating film naturally dried for about 30 minutes was irradiated with KrF excimer laser light (irradiation amount: 0.6 J / cm ² ).
The obtained surface-modified film was subjected to the above-mentioned adhesion durability test using a one-component addition type silicone rubber (volume resistivity: 1 × 10 ³ Ω · cm). Was.

Comparative Example 3 A test film prepared in the same manner as in Example 3 except that phenylsilane was not added to the pretreatment liquid was subjected to an adhesion durability test. After about 1500 hours, the silicone rubber was peeled off. No longer show.

When the surface-modified films obtained in Examples 1 to 3 were subjected to surface analysis by XPS (X-ray photoelectron spectroscopy), introduction of silicon atoms and an increase in the amount of oxygen atoms were confirmed.

[0033]

According to the present invention, it is possible to impart a high adhesive durability to a fluororesin molded article, particularly to a rubber, especially a highly conductive silicone rubber. In this case, excellent heat resistance, which is a characteristic of the fluororesin,
The chemical resistance and the electrical properties are not impaired.
Therefore, the fluororesin molded article surface-modified by the present invention can be used, for example, with various rollers (for example, a charging roller, a developing roller, a transfer roller, a fixing roller, and a pressure roller) used in an electronic copying machine or a laser beam printer. Roller, etc.).

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (reference) // C08L 27:12 C08L 27:12 F term (reference) 4F006 AA18 AB63 AB64 AB67 BA00 BA01 BA04 BA06 BA16 CA00 CA08 DA04 4F073 AA01 AA03 AA12 AA13 AA28 BA15 BA44 BA50 BB01 CA46 EA01 EA21 EA60 EA61 EA62 EA63 EA64 EA72 EA77 4J038 DL021 DL031 JC32 KA09 PA17 PC08

Claims (8)

[Claims] 1. A solution, dispersion or suspension containing an organosilicon compound, an ultraviolet-absorbing compound and a fluorine-based surfactant is attached to the surface of a fluororesin molded body, and the surface of the attachment is irradiated with ultraviolet laser light. A method for modifying the surface of a fluororesin molded body, characterized in that: 2. The method of claim 1, wherein the organosilicon compound is selected from the group consisting of (triphenylsilyl) acetylene, phenylsilane, tetraphenoxysilane, triphenylsilane, tribenzylsilane, allyltriphenylsilane, triphenylvinylsilane and phenyltriethoxysilane. 2. The method according to claim 1, which is one or more compounds. 3. The method according to claim 1, wherein the ultraviolet absorbing compound is an aromatic ultraviolet absorbing compound. 4. The aromatic ultraviolet absorbing compound is selected from aromatic hydrocarbons, aromatic carboxylic acids and salts thereof, aromatic aldehydes, aromatic alcohols, aromatic amines and salts thereof, and aromatic sulfonic acids. 3. The method according to claim 2, which is one or more compounds selected from the group consisting of and salts thereof and phenols. 5. A fluorosurfactant comprising a perfluoroalkyl phosphate, a perfluoroalkyl carboxylate,
The method according to claim 1, which is one or more surfactants selected from the group consisting of perfluoroalkyltrimethylammonium salts, perfluoroalkylbetaines, perfluoroalkylamine oxides and adducts of perfluoroalkylethylene oxide. 6. The method according to claim 1, wherein the ultraviolet laser light is an ArF excimer laser light, a KrF excimer laser light or a XeCl excimer laser light. 7. The method according to claim 1, wherein the surface of the fluororesin molding is coated with an aqueous solution of an organosilicon compound, an ultraviolet absorbing compound and a fluorine-based surfactant. 8. The method according to claim 1, wherein the surface of the fluororesin molding is coated with a lower alcohol solution of an organosilicon compound, an ultraviolet absorbing compound and a fluorine-based surfactant.