JP2860979B2 - Surface treatment method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating a surface of a substrate, which imparts a sufficient contamination-preventing effect to the surface of the substrate and also provides excellent weather resistance.

[0002]

2. Description of the Related Art Substrates such as glass and resin are used for automobile parts,
It is widely used as OA equipment and home electric appliances. On the surface of these substrates, garbage floating in cars, offices, indoors, etc. adheres, oily substances mixed with oils for foods and equipment, etc. which are difficult to wipe off, Fingerprints are adhered by hands and become contaminated, so that these contaminants are difficult to adhere.Furthermore, it is necessary to take measures for antifouling so that once contaminated substances can be easily removed. Become.

[0003] Japanese Patent Application Laid-Open No. 1-126244 and the like disclose a method for preventing stains on a glass surface by directly applying a polymer substance such as polydimethylsiloxane to the glass surface or immersing it in a treating agent. A forming technique is disclosed. Further, a technique of forming a chemically adsorbed monomolecular film containing fluorine on a glass surface by a chemisorption method is also known.

[0004] Japanese Patent Publication No. 7-53913 discloses that as a means for stain-proofing a metal surface, a chromate skin cover containing a silica sol silane coupling agent is formed on an upper layer of a zinc plating skin cover, and an isocyanate based cover is formed on the upper layer. There is disclosed a technique relating to an organic composite plated steel sheet which is coated with a thin film using a coating composition.

Further, in order to enhance the antifouling effect of the antireflection filter, there has been proposed a technique of forming a film of a compound obtained by subjecting a perfluoropolyether compound to silane treatment on the upper layer of the antireflection film.

[0006]

However, all of the above-mentioned techniques have a certain effect in order to enhance the effect of preventing pollution, but the effect is remarkable under severe conditions such as outdoor exposure. It was not satisfactory in terms of weather resistance. In view of the above situation,
SUMMARY OF THE INVENTION An object of the present invention is to provide a method for treating a surface of a substrate, which has a sufficient contamination-preventing action, has a permanent action, and has sufficient weather resistance.

[0007]

The surface treatment method of the present invention comprises a silicon-containing organic fluorine-containing polymer (1) represented by the following general formula (I), a fluorine-containing organic solvent (2), and a silane compound ( A method for treating a surface of a substrate, characterized by applying a treatment liquid containing 3) to the surface of the substrate.

[0008]

Embedded image

In the formula, Rf represents a perfluoroalkyl group. Z represents a fluorine or trifluoromethyl group.
a, b, c, d, and e each independently represent 0 or an integer of 1 or more, and a + b + c + d + e is at least 1
As described above, the order in which the repeating units defined by a, b, c, d, and e are present is not limited in the formula. Y
Represents hydrogen or an alkyl group having 1 to 4 carbon atoms. X is
Represents hydrogen, bromine or iodine. R ¹ represents a hydroxyl group or a hydrolyzable substituent. R ² represents hydrogen or a monovalent hydrocarbon group. l represents 0, 1 or 2. m is 1,
Represents 2 or 3. n represents an integer of 1 or more. Hereinafter, the present invention will be described in detail.

[0010] The surface treatment method of the present invention comprises applying a treatment liquid to the surface of a substrate. The first component of the treatment liquid is the silicon-containing organic fluoropolymer (1) represented by the general formula (I). In the formula represented by the above general formula (I), Rf is not particularly limited as long as it is a perfluoroalkyl group constituting the organic fluoropolymer, and may be, for example, a linear or linear C1-16 group. Branched ones can be mentioned. Preferably, CF ₃ -, C ₂ F
₅ -, C ₃ F ₇ - a.

Z in the above formula (I) may be fluorine or a trifluoromethyl group. The above general formula (I)
A, b, c, d, and e represent the number of repeating units of the perfluoropolyether chain constituting the main skeleton of the silicon-containing organic fluorine-containing polymer, and are 0 or an integer of 1 or more.
Although it is not particularly limited as long as + b + c + d + e is 1 or more, it is preferably independently 0 to 200, and more preferably independently 0 to 50 in consideration of the molecular weight of the silicon-containing organic fluorine-containing polymer described later. It is. a + b + c + d + e is preferably 1 to 100.

The order of existence of the repeating units a, b, c, d, and e is described in this order in the general formula (I) for convenience. In view of the above, the bonding order of these repeating units is not limited to this order.

Y in the above formula (I) represents hydrogen or an alkyl group having 1 to 4 carbon atoms. The alkyl group having 1 to 4 carbon atoms is not particularly limited, and includes, for example, methyl, ethyl, propyl, butyl and the like, and may be linear or branched. X of the above general formula (I)
Represents hydrogen, bromine or iodine. When X is bromine or iodine, the silicon-containing organic fluorine-containing polymer of the present invention has high radical reactivity, so that it is convenient to bond it to another compound by a chemical bond.

In the general formula (I), 1 represents the number of carbon atoms of the alkylene group existing between the carbon constituting the perfluoropolyether chain and silicon bonded thereto, and
Or 2, more preferably 0.

M in the above general formula (I) represents the number of substituents R ¹ bonded to silicon, and is 1, 2 or 3.
R ² is bonded to the silicon where the substituent R ¹ is not bonded.

R ¹ represents a hydroxyl group or a hydrolyzable substituent. The hydrolyzable substituent is not particularly limited, and is preferably, for example, halogen,
-OR ³ , -OCOR ³ , -OC (R ³ ) = C (R ⁴ )
^{_{2, -ON = C (R 3}} ) 2, -ON = CR 5 [ wherein, R
³ represents an aliphatic hydrocarbon group or an aromatic hydrocarbon group,
R ⁴ represents hydrogen or an aliphatic hydrocarbon group having 1 to 4 carbon atoms, and R ⁵ represents a divalent aliphatic hydrocarbon group having 3 to 6 carbon atoms. And the like. More preferably, chlorine, -OCH _3, is -OC ₂ H _5.

R ² represents hydrogen or a monovalent hydrocarbon group. The monovalent hydrocarbon group is not particularly limited,
Preferred examples include methyl, ethyl, propyl, butyl and the like, which may be linear or branched.

In the general formula (I), n represents an integer of 1 or more, and there is no particular upper limit. However, in order to achieve the object of the present invention, n is preferably an integer of 1 to 10. The above n
Represents an integer in the general formula (I), and the silicon-containing organic fluoropolymer according to the present invention exists as a mixture of the polymer represented by the general formula (I) having such an integer n. Is also good. As described above, when the silicon-containing organic fluoropolymer is present as a mixture, the above n can be represented as an average value in the mixture, and when the silicon-containing organic fluoropolymer is present as a mixture, In consideration of the object of the present invention, the average value of n is preferably 1.3 to 3, and particularly preferably 1.5 to 2.5.

The silicon-containing organic fluoropolymer preferably has a molecular weight of 5 × 10 ² to 1 × 10 ⁵ . 5 × 10
^If it is less than ² , the effect of the present invention will not be exhibited, and if it exceeds 1 × 10 ⁵ , processability will be poor. More preferably, 1 × 10
^{It is 3} to 1 × 10 ⁴ .

Preferred examples of the silicon-containing organic fluorine-containing polymer include, for example, those represented by the following general formula (II).

[0021]

Embedded image

In the formula, p represents an integer of 1 or more. Y,
X, R ¹ , R ² , l, m, and n are the same as described above. P in the general formula (II) is not particularly limited as long as it is an integer of 1 or more, but is preferably 1 to 200, and more preferably 1 in consideration of the molecular weight of the silicon-containing organic fluoropolymer of the present invention. ~ 50.

The silicon-containing organic fluoropolymer preferably has a molecular weight of 5 × 10 ² to 1 × 10 ⁵ . 5 × 10
^If it is less than ² , the effect of the present invention will not be exhibited, and if it exceeds 1 × 10 ⁵ , processability will be poor. More preferably, 1 × 10
^{It is 3} to 1 × 10 ⁴ .

The above silicon-containing organic fluorine-containing polymer is
Usually, commercially available perfluoropolyether is used as a raw material and, for example, iodine is introduced into the terminal, and then, for example, the following general formula [wherein, Y, R ¹ , R ² , l,
m is the same as above. For example, by reacting a vinylsilane compound represented by the formula

[0025]

Embedded image

The second component constituting the treatment liquid used in the surface treatment method of the present invention is a fluorinated organic solvent (2). The fluorinated organic solvent (2) is not particularly limited, and examples thereof include perfluorohexane, perfluoromethylcyclohexane, perfluoro-1,3-dimethylcyclohexane, and HCFC225. Among them, HCFC225 is preferred because the silicon-containing organic fluoropolymer (1) can be easily dissolved and is easily available.

The third component constituting the treatment liquid used in the surface treatment method of the present invention is a silane compound (3). The silane compound (3) is not particularly limited,
For example, general formula (III) Si (OR ¹¹ ) ₄ (III) [wherein, R ¹¹ represents an aliphatic hydrocarbon group, and its carbon number is not particularly limited. Alkoxide compounds of silicon represented by the general formula (III), and partial hydrolysis condensation products of the compounds represented by the general formula (III). Above all,
Tetraethoxysilane is preferred because it is easily available.

The composition ratio of each of the components (1), (2) and (3) constituting the treatment liquid used in the surface treatment method of the present invention is not particularly limited, but (1) :( 2) is The weight ratio is preferably from 1: 1 to 1: 10000. (1)
If the amount of the component is too large, the viscosity of the solution will increase, thereby impairing the workability. If the amount is too small, the effect of preventing contamination will be insufficient. More preferably, it is 1: 4 to 1: 1000. Further, (1) :( 3) is preferably in a weight ratio of 10: 1 to 1: 100. (1) If the amount of the component is too large, the effect of improving the weather resistance will be insufficient, and if it is too small, the effect of preventing contamination will be insufficient. More preferably, 5:
1 to 1:10.

In applying the treatment liquid of the present invention, for example, fine powder fillers such as silica, alumina, titanium oxide, carbon and cement, alkoxides such as titanium and aluminum, and other low molecular weight polytetrafluoroethylene, A fine powder of a fluororesin such as a tetrafluoroethylene / hexafluoropropylene copolymer or the like can be added as a hardness adjuster or an extender. Further, the hardness can be adjusted by further adding a usual crosslinking agent or a curing catalyst such as water, hydrochloric acid, sulfuric acid, carboxylic acid, sulfonic acid and the like.

In applying the treatment liquid of the present invention, a method of applying the treatment liquid to the surface of a target substrate can be employed. Examples of the coating method include brush coating, spray coating, spin coating, dip coating,
Roll coating, gravure coating, curtain flow coating and the like can be mentioned.

In the surface treatment method of the present invention, the thickness of the layer formed by the treatment liquid is not particularly limited, but is preferably 0.001 to 0.03 μm. 0.
If it is less than 001 μm, the effect of preventing contamination is poor,
If the thickness exceeds 0.03 μm, the layer is too thick, which causes an obstacle in use, which is not preferable.

The surface treatment method according to the second aspect of the present invention provides a treatment solution comprising a silicon-containing organic fluoropolymer (1) represented by the general formula (1) and a fluoroorganic solvent (2) ( M) is applied to the surface of a substrate having an underlayer formed on the surface thereof using a treatment liquid (N) containing a silane compound [excluding the silicon-containing organic fluoropolymer (1)] (3). It consists of doing.

The silane compound (3) is treated with an organic solvent such as methyl alcohol, ethyl alcohol, isopropyl alcohol, ethyl acetate, acetone or the like or a water solvent to obtain a treatment solution (N) having a predetermined concentration. The concentration is not particularly limited, but is preferably in the range of 2 to 80% by weight. If it is less than 2% by weight, it takes a long time to form the silica sol, and if it exceeds 80% by weight, the liquid viscosity becomes too high and the workability is impaired. The above treatment liquid (N)
Then, an ordinary catalyst, for example, hydrochloric acid is added thereto, and the mixture is allowed to stand for a predetermined period of time to form a silica sol. The standing time is not particularly limited, but is, for example, 2 to 10 days. The dilution concentration varies depending on the desired thickness of the underlayer, but is, for example, in the range of 0.2 to 2% by weight.

Next, the diluted treatment liquid (N) is applied to the surface of the substrate. As the application method, for example, brush coating, spray coating, spin coating, dip coating, roll coat coating,
Gravure coat coating, curtain flow coating and the like can be mentioned. By the above operation, a gel layer of the silanol polymer is formed on the surface of the base material.

Next, by heating the base material, an underlayer mainly composed of silicon oxide can be formed. The heating temperature varies depending on the base material.
~ 300 ° C. The heating time is not particularly limited, but is, for example, in the range of 10 minutes to 3 hours. Although the thickness of the formed underlayer is not particularly limited, it is usually 0.05
０．１0.1 μm.

Thereafter, the treatment liquid (M) is applied to the surface of the substrate having the underlayer formed on the surface. Examples of the coating method include brush coating, spray coating, spin coating, dip coating, roll coating, gravure coating, curtain flow coating, and the like.

In the surface treatment method of the present invention, the thickness of the layer formed by the treatment liquid (M) is not particularly limited, but is preferably 0.001 to 0.03 μm. If it is less than 0.001 μm, the effect of preventing contamination is poor, and if it is more than 0.03 μm, the layer is too thick, and it is not preferable because it causes trouble in use.

The substrate to which the surface treatment method of the present invention can be applied includes, for example, the following easily contaminated portions and the like. Accessories such as tie pins, necklaces, and earrings; taps, brass instruments, woodwind instruments, golf clubs, door handles, dumbbells,
Metal or plated products such as cutlery; ceramic materials such as insulators, tiles, sanitary ware, tableware, and roof tiles; stone materials such as tombstones, go stones, and marble; Leather products such as shoes, bags, watch bands and baseball gloves.

Household electric appliances such as fan blades, microwave oven doors, refrigerator surfaces, etc .; contact glass for copy machines, OH
Mirror of P body, OHP sheet, keyboard, telephone,
Office supplies such as office desks; Housewares such as glasses, cupboard doors, mirrors, window glasses, light umbrellas, chandeliers; Building materials such as show windows, telephone boxes, aquarium glass;
Vehicle parts such as vehicle glass and painted surface of car body; Glasses frame, underwater glasses glass, goggles, helmet, clock face cover glass and other accessories; Pachinko glass, playing cards, Mahjong pie, etc .; Painted surfaces such as pianos.

The surface treatment method of the present invention is characterized by the fact that the contamination preventing action is permanent and that it has sufficient weather resistance, so that it is suitable for applying the surface treatment method of the present invention. Among the above-mentioned various substrates, for example, those listed below are preferable. Door handles; Ceramic materials such as roof tiles; Stone materials such as tombstones, go stones, marbles, etc .; Contact glass for photocopiers; Window glass; Vehicle parts such as vehicle glass and painted surfaces; Glass for pachinko machines; Play equipment.

[0041]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Synthesis Example 1 In a 2.0 L four-necked flask equipped with a stirrer, a dropping funnel, a reflux condenser and a thermometer, 2617 g (10.3 mol) of iodine and 213.2 g (1.54 mol) of potassium carbonate And 9000 g of hexachloro-1,3-butadiene were charged, and while maintaining the temperature of the system at 160 ° C., under a nitrogen stream, the chemical formula F- (CF ₂ CF ₂ CF ₂ O) n
Ω-fluoropolyperfluorooxetane acyl fluoride represented by —CF ₂ CF ₂ COF (average molecular weight 3
900) 4000 g (1.03 mol) was added dropwise at a rate of 10 mL / min.

After the completion of the dropwise addition, the reaction temperature was raised to 185 ° C., and the reaction was carried out for 20 hours. After completion of the reaction, the system was cooled, and the potassium salt was separated by filtration. From the liquid phase separated into two layers, the lower layer was separated using a separating funnel. This was washed several times with acetone, dissolved in 1 L of perfluorohexane, and fine insolubles were filtered off with a glass filter. The volatiles were completely distilled off from the resulting solution under reduced pressure to obtain 3890 g (yield 95%) of the chemical formula F- (C
_{F 2 CF 2 CF 2 O)} ω represented by n -CF ₂ CF ₂ I
-A fluoropolyperfluorooxetane iodide was obtained. According to the infrared absorption spectrum, -C at 1890 cm ^-1
The absorption of (＝ O) F completely disappeared, and a new absorption of —CF ₂ I occurred at 910 cm ⁻¹ . From ¹⁹ F-NMR using trichlorofluoromethane (CFC-11) as a standard, 2
Absorption of 0.7 ppm of -C (= O) F completely disappears,
At −66.7 ppm, absorption originating from —OCF ₂ CF ₂ I occurs, and at −87.6 ppm, —OCF ₂ CF
Absorption occurs derived from the ₂ I. From the integral, the conversion is 1
00% was calculated.

Synthesis Example 2 A sample equipped with a stirrer, a dropping funnel, a reflux condenser and a thermometer was prepared.
00mL4 one during neck flask was synthesized in Synthesis Example 1 formula _{F- (CF 2 CF 2 CF 2} O) represented by n -CF ₂ CF ₂ I ω- fluoropolyether perfluoro oxetane iodide 40g die chlorofluorocarbon solvent 80 g of S-316 (manufactured by Daikin Industries, Ltd.) and 1.5 g (1 × 10 ^-2 mol) of di-t-butyl peroxide were charged, and the inside of the system was sufficiently purged with nitrogen. 16.1 g (0.10 g) of vinyltrichlorosilane was dropped from the dropping funnel.
Mol) was added dropwise. After completion of the dropwise addition, the temperature in the system was raised to 120 ° C., and the reaction was performed for 4 hours. After completion of the reaction, volatile matters were completely distilled off under reduced pressure to obtain 38.7 g (yield: 90%) of a silicon-containing organic fluorine-containing polymer having terminal iodine (A). ¹⁹ F-NM with CFC-11 as standard
From R, the absorption at -66.7 ppm and -87.6 ppm completely disappeared, and a wide absorption band appeared at -89.2 to -90.0 ppm. Also, from ¹ H-NMR, 1.4 to
Although broad absorption band appeared at 3.0 ppm, the chemical formula as an internal standard _{F- (CF 2 CF 2 CF 2} O) n -CF 2 CF
_The degree of polymerization of trichlorovinylsilane was calculated to be 2.0 by adding 5.0 mol% of ω-fluoropolyperfluorooxetane hydride represented by ₂ H.

Synthesis Example 3 2 equipped with a stirrer, a dropping funnel, a reflux condenser and a thermometer
In a 00 mL four-necked flask, 34.4 g of the silicon-containing organic fluoropolymer (A) synthesized in Synthesis Example 2 (8 × 1
( ^0.3 mol) was dissolved in 50 g of perfluorohexane, and 2.1 g (3.2 × 10 ^-2 mol) of zinc was dispersed under vigorous stirring. The system was cooled in an ice water bath, and 10 g of anhydrous methanol was added dropwise under a nitrogen stream. After completion of the dropwise addition, the ice-water bath was removed, and the reaction was carried out for 2 hours while heating under reflux. After completion of the reaction, insolubles were separated by filtration, and the lower layer was separated from the liquid phase separated into two layers using a separating funnel. After the obtained solution was washed three times with anhydrous methanol, the volatile components were completely distilled off under reduced pressure, whereby 31.6 g of a hydrogenated silicon-containing organic fluorine-containing polymer (B) was obtained (yield). 92%).
^{From 1} H-NMR, absorption of Si—OCH ₃ appeared at 3.5 ppm. The chemical formula F- (CF ₂ CF _{2
CF 2 O) n -CF 2 CF} 2 was added ω- fluoropolyether perfluoro oxetane hydride 5.0 mol% represented by H, the integrated intensity of the broad absorption bands of 1.2~3.0ppm 16. It was confirmed that the degree of polymerization was 2.0 from an increase in 0% and an intensity ratio with the absorption band of 3.5 ppm.

Example 1 Silicon-containing organic fluorine-containing polymer (B) obtained in Synthesis Example 3
A treatment liquid was prepared by mixing 99.8% by weight of HCFC225 and 0.1% by weight of tetraethoxysilane with 0.1% by weight. The glass plate was washed with water before use, and then thoroughly washed with methanol and acetone. The glass plate thus prepared was dipped in the above-mentioned treatment solution for 1 minute, pulled up, and then dried at 60 ° C. and 80% RH.
Let stand for minutes. Then, it was sufficiently washed with HCFC 225 to remove excess processing solution molecules. The sample prepared in this manner is used for 16 hours (equivalent to 3.3 years) in a sunshine weatherometer (manufactured by Iwasaki Electric Co., SUV-W13).
Was subjected to an accelerated weather resistance test, and the contact angle with water was compared before and after the test. The water contact angle was measured using a contact angle meter (CA-DT type manufactured by Kyowa Interface Science Machine Co., Ltd.). The results are shown in Table 1.

Comparative Example 1 The silicon-containing organic fluorine-containing polymer (B) obtained in Synthesis Example 3
A processing liquid was prepared in the same manner as in Example 1, except that 99.9% by weight of HCFC225 was mixed with 0.1% by weight, and a test liquid was similarly provided. Table 1 shows the results
It was shown to.

[0048]

[Table 1]

[0049]

Since the surface treatment method of the present invention has the above-mentioned structure, it has a sufficient effect of preventing contamination, has a long-lasting effect, and has sufficient weather resistance. It can be suitably used for a substrate that requires a contamination prevention action under a variety of conditions.

Continuation of front page (56) References JP-A-50-97616 (JP, A) JP-A-4-224137 (JP, A) JP-A-9-124998 (JP, A) JP-A-9-61605 (JP, A) (A) JP-A-1-294709 (JP, A) (58) Fields studied (Int. Cl. ⁶ , DB name) C03C 17/30 C08G 65/48 C08J 7/04 C09D 171/02

Claims (5)

(57) [Claims] 1. A silicon-containing organic fluorine-containing polymer (1), a fluorine-containing organic solvent (2) and a silane compound represented by the following general formula (I), provided that the silicon-containing organic fluorine-containing polymer (1) Exclude] A method for treating the surface of a substrate, comprising applying a treatment liquid containing (3) to the surface of the substrate. Embedded image In the formula, Rf represents a perfluoroalkyl group. Z is
Represents a fluorine or trifluoromethyl group. a, b, c,
d and e each independently represent an integer of 0 or 1 or more, and a + b + c + d + e is at least 1 or more;
The order in which the repeating units a, b, c, d, and e are present is not limited in the formula. Y represents hydrogen or an alkyl group having 1 to 4 carbon atoms. X represents hydrogen, bromine or iodine. R ¹ represents a hydroxyl group or a hydrolyzable substituent. R ² represents hydrogen or a monovalent hydrocarbon group.
l represents 0, 1 or 2. m represents 1, 2 or 3. n represents an integer of 1 or more. 2. A treatment liquid (N) containing a silane compound (excluding a silicon-containing organic fluoropolymer (1) represented by the following general formula (1)) (3) is applied to the surface of a substrate. After coating to form a base layer, a treatment liquid (M) containing a silicon-containing organic fluoropolymer (1) represented by the following general formula (1) and a fluoroorganic solvent (2) Is applied on the undercoat layer. Embedded image In the formula, Rf represents a perfluoroalkyl group. Z is
Represents a fluorine or trifluoromethyl group. a, b, c,
d and e each independently represent an integer of 0 or 1 or more, and a + b + c + d + e is at least 1 or more;
The order in which the repeating units a, b, c, d, and e are present is not limited in the formula. Y represents hydrogen or an alkyl group having 1 to 4 carbon atoms. X represents hydrogen, bromine or iodine. R ¹ represents a hydroxyl group or a hydrolyzable substituent. R ² represents hydrogen or a monovalent hydrocarbon group.
l represents 0, 1 or 2. m represents 1, 2 or 3. n represents an integer of 1 or more. 3. The silicon-containing organic fluoropolymer has a molecular weight of 5 × 10 ² to 1 × 10 ^5.
Or the surface treatment method according to 2. 4. Silicon-containing organic fluoropolymer (1)
Is a silicon-containing organic fluorine-containing polymer represented by the following general formula (II). Embedded image In the formula, p represents an integer of 1 or more. Y represents hydrogen or an alkyl group having 1 to 4 carbon atoms. X represents hydrogen, bromine or iodine. R ¹ represents a hydroxyl group or a hydrolyzable substituent. R ² represents hydrogen or a monovalent hydrocarbon group. l
Represents 0, 1 or 2. m represents 1, 2 or 3.
n represents an integer of 1 or more. 5. The silicon-containing organic fluorine-containing polymer has a molecular weight of 5 × 10 ² to 1 × 10 ^5.
The surface treatment method described.