Water/oil-repellent treatment agent having heat resistance, method of preparation, and treated article

Abstract

A water/oil repellent treatment agent which includes a specific polymer-modified silane having a fluorooxyalkylene structure on the main chain and a hydrolyzable group at the end of the molecular chain, and/or a partial (co)hydrolyzate/condensate thereof, has a percent weight loss following one hour of exposure at 250° C. of 10% or less. The treatment forms a layer having excellent water and oil repellency, scuff resistance and mold release properties even when heated to 250° C. or more.

Claims

1. A water/oil repellent treatment agent comprising at least one compound selected from the group consisting of fluorooxyalkylene group-containing polymer-modified silanes of general formulas (1) to (4) below
A-Rf-QZW.sub.α  (1)
Rf-(QZW.sub.α).sub.2  (2)
A-Rf-Q-(Y).sub.βB  (3)
Rf-(Q-(Y).sub.βB).sub.2  (4), wherein Rf is —(CF.sub.2).sub.d—(OCF.sub.2).sub.p(OCF.sub.2CF.sub.2).sub.q(OCF.sub.2CF.sub.2CF.sub.2).sub.r(OCF.sub.2CF.sub.2CF.sub.2CF.sub.2).sub.s(OCF(CF.sub.3)CF.sub.2).sub.t—O(CF.sub.2).sub.d—, each d being independently an integer from 0 to 5, p, q, r, s and t being each independently an integer from 0 to 500, with the proviso that the sum p+q+r+s+t=40 to 500, and each unit shown in parentheses being randomly bondable; A is a fluorine atom, a hydrogen atom, or a monovalent fluorine-containing group having a terminal —CF.sub.3 group, —CF.sub.2H group or —CH.sub.2F group; Q is independently a single bond or a divalent organic group which may be fluorine-substituted and does not contain a hydrocarbon ether bond; Z is independently a group selected from the group consisting of a single bond, the divalent group -J.sub.2C— (where J is independently an alkyl group, a hydroxyl group or the silyl ether group K.sub.3SiO— (K being independently a hydrogen atom, an alkyl group, an aryl group or an alkoxy group), the divalent group -L.sub.2Si— (where L is independently an alkyl group, an alkenyl group, an alkoxy group or a chloro group), the trivalent group -JC═ (where J is as defined above), the trivalent group -LSi═ (where L is as defined above), the tetravalent group —C≡, the tetravalent group —Si≡, and siloxane residues having a valence of 2 to 8; W is independently a hydrolyzable group-bearing moiety of any of general formulas (5a) to (5e) below ##STR00022## R being independently an alkyl group of 1 to 4 carbon atoms or a phenyl group, X being independently a hydrolyzable group, the letter “a” being 2 or 3, the letter “l” being an integer from 0 to 10, each m being independently an integer from 1 to 10, D being a single bond or a divalent organic group of 1 to 20 carbon atoms which may be fluorine-substituted, b being an integer from 2 to 6, c being an integer from 1 to 50, and Me being a methyl group; α is an integer from 1 to 7; Y is independently a divalent group having a hydrolyzable group; β is in each instance an integer from 1 to 10; and B is independently a hydrogen atom, an alkyl group of 1 to 4 carbon atoms, or a halogen atom, and partial (co)hydrolyzates/condensates thereof in an amount of at least 50% of the total weight exclusive of diluting solvent, wherein the treatment has a percent weight loss after one hour of exposure at 250° C. that is not more than 10% of the total weight exclusive of diluting solvent.

2. The treatment agent of claim 1, wherein Y is selected from the group consisting of groups of general formulas (6) to (8) below ##STR00023## wherein R, X, the letter “a” and D are as defined above, D′ is a divalent organic group of 1 to 10 carbon atoms that may be fluorine-substituted, R.sup.1 is a monovalent hydrocarbon group of 1 to 20 carbon atoms, and e is 1 or 2.

3. The treatment agent of claim 1, wherein Q is selected from the group consisting of a single bond and divalent groups of the following formulas ##STR00024## wherein f is an integer from 2 to 4, g is an integer from 1 to 4, h is an integer from 1 to 50, and Me is a methyl group.

4. The treatment agent of claim 1, wherein the hydrolyzable group X is selected from the group consisting of alkoxy groups of 1 to 10 carbon atoms, alkoxyalkoxy groups of 2 to 10 carbon atoms, acyloxy groups of 1 to 10 carbon atoms, alkenyloxy groups of 2 to 10 carbon atoms, halogen groups, and silazane groups.

5. The treatment agent of claim 1, further comprising a fluorooxyalkylene group-containing polymer of general formula (9) below
A-Rf-A  (9), wherein Rf and A are as defined above, which fluorooxyalkylene group-containing polymer accounts for at least 0.1 wt % and not more than 50 wt % of the combined amount of the fluorooxyalkylene group-containing polymer-modified silane and/or the partial (co)hydrolyzate/condensate thereof and the fluorooxyalkylene group-containing polymer.

6. An article treated with the water/oil repellent treatment agent of claim 1.

7. An optical article treated with the water/oil repellent treatment agent of claim 1.

8. Glass, chemically toughened glass, physically toughened glass, SiO.sub.2-treated glass, sapphire glass, SiO.sub.2-treated sapphire glass, a quartz substrate, a silicon wafer or a metal treated with the water/oil repellent treatment agent of claim 1.

9. A touch panel, anti-reflective coating, wearable device, photovoltaic panel or transportation equipment window treated with the water/oil repellent treatment agent of claim 1.

10. An imprinting mold treated with the water/oil repellent treatment agent of claim 1.

11. A method of preparing the water/oil repellent treatment agent of claim 1, comprising the step of: thin-film distilling, in the temperature range of 150 to 400° C., the at least one compound selected from the group consisting of fluorooxyalkylene group-containing polymer-modified silanes of formulas (1) to (4) and partial (co)hydrolyzates/condensates thereof to remove low-boiling components.

12. A method of preparing the water/oil repellent treatment agent of claim 5, comprising the step of: thin-film distilling, in the temperature range of 150 to 400° C., a mixture of the at least one compound selected from the group consisting of fluorooxyalkylene group-containing polymer-modified silanes of formulas (1) to (4) and partial (co)hydrolyzates/condensates thereof with the fluorooxyalkylene group-containing polymer of formula (9) to remove low-boiling components.

13. A method of preparing the water/oil repellent treatment agent of claim 5, comprising the steps of: separately thin-film distilling, in the temperature range of 150 to 400° C., the at least one compound selected from the group consisting of fluorooxyalkylene group-containing polymer-modified silanes of formulas (1) to (4) and partial (co)hydrolyzates/condensates thereof and the fluorooxyalkylene group-containing polymer of formula (9) to remove low-boiling components; and mixing together the residue from each distillation.

14. The treatment agent of claim 1, wherein α is an integer of from 2 to 7 in general formula (1) or (2) and β is an integer of from 2 to 10 in general formula (3) or (4).

Description

EXAMPLES

(1) Preparation Examples, Working Examples and Comparative Examples are given below by of illustration and not by way of limitation.

(2) The following compositions were prepared as water/oil repellent treatment agents.

Preparation Example 1

(3) A 100 mL three-neck flask fitted with a Dimroth condenser, a dropping funnel, a thermometer and a magnetic stirrer was charged with 30 g of the iodo-terminated fluorinated compound having the average compositional formula (1a) below (number-average molecular weight, 3,700; iodo group concentration=0.026 mol/100 g), 1.12 g of di-t-butyl peroxide, 11.5 g of a vinyl group-containing silane compound (1b) (vinyl group concentration=0.272 mol/100 g), and 30 g of 1,3-bistrifluoromethylbenzene, and the flask interior was flushed with nitrogen. Reaction was carried out at 100° C. for 3 hours under stirring, followed by cooling to room temperature (20° C.). Next, 1.02 g of zinc powder and 30 g of methyl alcohol were added and the reaction was carried out for 12 hours at an internal temperature of 60° C. and under vigorous stirring. The reaction mixture was filtered to remove the solids, and then subjected to stripping treatment under conditions of 100° C./1 mmHg to remove solvent components, unreacted silane and low-boiling components, giving 28 g of a product of formula (1c) below. FT-IR, .sup.1H-NMR and .sup.19F-NMR analysis confirmed the loss of the terminal iodine group, the loss of the vinyl group and the presence of methoxy groups. This product is referred to below as Composition 1-1.

(4) ##STR00019##
Here, p2/q2≈1.1 and p2+q2≈38.

Preparation Example 2

(5) Composition 1-1 was subjected to thin-film distillation at 1×10.sup.−2 Pa and 130° C. to remove low-boiling components. The resulting composition was designated as Composition 1-2. The yield was 85%. In formula (1c), p2/q2≈1.1 and p2+q2≈43.

Preparation Example 3

(6) Composition 1-1 was subjected to thin-film distillation at 1×10.sup.−2 Pa and 220° C. to remove low-boiling components. The resulting composition was designated as Composition 1-3. The yield was 68%. In formula (1c), p2/q2≈1.1 and p2+q2≈64.

Preparation Example 4

(7) Composition 1-1 was subjected to thin-film distillation at 1×10.sup.−2 Pa and 300° C. to remove low-boiling components. The resulting composition was designated as Composition 1-4. The yield was 36%. In formula (1c), p2/q2≈1.1 and p2+q2≈81.

Preparation Example 5

(8) A 100 mL three-neck flask fitted with a Dimroth condenser, a dropping funnel, a thermometer and a magnetic stirrer was charged with 30 g of the carbonyl-containing fluorinated compound of the average compositional formula (2a) below (number-average molecular weight, 3,700; carbonyl group concentration=0.028 mol/100 g), 15 g of a diethyl ether solution of allylmagnesium bromide (bromo group concentration, 0.05 mol/100 g), 30 g of 1,3-bistrifluoromethylbenzene and 10 g of tetrahydrofuran, and the flask interior was flushed with nitrogen. Reaction was carried out at 60° C. for 6 hours under stirring, followed by cooling to room temperature (20° C.). Next, the reaction mixture was slowly added to a separatory funnel containing an aqueous hydrochloric acid (a mixture of 6 g of 12 N hydrochloric acid and 54 g of water) and the contents were stirred 30 minutes, following which the bottom phase was recovered. The recovered liquid was subjected to stripping treatment under 110° C./1 mmHg conditions to remove the solvent components, giving 25 g of a product of formula (2b) below. FT-IR, .sup.1H-NMR and .sup.19F-NMR analysis confirmed the loss of the methyl ester group and the presence of allyl groups.

(9) The resulting product of formula (2b) was subjected to thin-film distillation at 1×10.sup.−2 and 300° C. to remove low-boiling components. The yield was 37%.

(10) Next, a reaction vessel was charged with 20 g of the product from which low-boiling components had been removed by thin-film distillation and 0.04 g of a toluene solution of the catalyst obtained by modifying chloroplatinic acid with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane (platinum concentration, 0.5 wt %), and the contents were heated to an internal temperature of 80° C. under stirring. Trimethoxysilane (SiH group concentration=0.0082 mol/g), 2.8 g, was added dropwise over about 10 minutes from a dropping funnel, and maturing was carried out for 2 hours at an internal temperature of 80 to 90° C. This was followed by stripping treatment at 100° C./5 mmHg to remove surplus silane, giving 21 g of the product of formula (2c) below. FT-IR, .sup.1H-NMR and .sup.19F-NMR analysis confirmed the loss of the allyl groups and the loss of the SiH group. This product is referred to below as Composition 2-1.

(11) ##STR00020##
In formulas (2a) to (2c), p2/q2≈1.1 and p2+q2≈78.

Preparation Example 6

(12) The compound of formula (2a) was subjected to thin-film distillation at 1×10.sup.−2 Pa and 300° C. to remove low-boiling components, whereupon the yield was 40%. Aside from using the product thus recovered instead of the compound of formula (2a) in Preparation Example 5 and eliminating the thin-film distillation step, a compound to which trimethoxysilane had been added (2c) was obtained by the same method as in Preparation Example 5. In formula (2c), p2/q2≈1.1 and p2+q2≈79. This product is referred to below as Composition 3-1.

Preparation Example 7

(13) A 100 mL three-neck flask fitted with a Dimroth condenser, a dropping funnel, a thermometer and a magnetic stirrer was charged with 30 g of the allyl-terminated fluorinated compound of the average compositional formula (3a) below (number-average molecular weight, 3,700; allyl group concentration=0.026 mol/100 g) and 0.05 g of a toluene solution of the catalyst obtained by modifying chloroplatinic acid with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane (platinum concentration, 0.5 wt %), and the contents were heated to an internal temperature of 80° C. under stirring. Trimethoxysilane (SiH group concentration=0.0082 mol/g), 1.2 g, was added dropwise over about 5 minutes from a dropping funnel, and maturing was carried out for 2 hours at an internal temperature of 80 to 90° C. This was followed by stripping treatment at 100° C./5 mmHg to remove surplus silane, giving 31 g of the product of formula (3b) below. FT-IR, .sup.1H-NMR and .sup.19F-NMR analysis confirmed the loss of the allyl groups and the loss of the SiH group. This product is referred to below as Composition 4-1.

(14) ##STR00021##
In formulas (3a) and (3b), p2/q2≈1.0 and p2+q2≈38.

Preparation Example 8

(15) Composition 4-1 was subjected to thin-film distillation at 1×10.sup.−2 Pa and 130° C. to remove low-boiling components. The resulting composition was designated as Composition 4-2. The yield was 81%. In formula (3b), p2/q2≈1.1 and p2+q2≈45.

Preparation Example 9

(16) Composition 4-1 was subjected to thin-film distillation at 1×10.sup.−2 Pa and 220° C. to remove low-boiling components. The resulting composition was designated as Composition 4-3. The yield was 55%. In formula (3b), p2/q2≈1.1 and p2+q2≈69.

Preparation Example 10

(17) Composition 4-1 was subjected to thin-film distillation at 1×10.sup.−2 Pa and 300° C. to remove low-boiling components. The resulting composition was designated as Composition 4-4. The yield was 27%. In formula (3b), p2/q2≈1.1 and p2+q2≈85.

Preparation Example 11

(18) A mixture of 40 parts by weight of the nonfunctional perfluoropolyether FOMBLIN M07 (available under the trade name from Solvay Solexis) mixed with 60 parts by weight of Composition 1-4 was designated as Composition 5.

Preparation Example 12

(19) A mixture of 40 parts by weight of the component obtained by thin-film distillation of the nonfunctional perfluoropolyether FOMBLIN M07 at 1×10.sup.−2 Pa and 300° C. with 60 parts by weight of Composition 1-4 was designated as Composition 6.

Preparation Example 13

(20) A mixture of 60 parts by weight of the component obtained by thin-film distillation of the nonfunctional perfluoropolyether FOMBLIN M07 at 1×10.sup.−2 Pa and 300° C. with 40 parts by weight of Composition 1-4 was designated as Composition 7.

Preparation Example 14

(21) The product obtained by subjecting a mixture of 40 parts by weight of the nonfunctional perfluoropolyether FOMBLIN M07 with 60 parts by weight of Composition 1-1 to thin-film distillation at 1×10.sup.−2 Pa and 300° C. was designated as Composition 8. The yield was 35%.

(22) Method of Measuring Percent Weight Loss

(23) Each composition, in an amount of about 20 mg, was placed in an alumina sample pan having a diameter of 4.5 mm and depth of 2 mm, and the weight after one hour of exposure at 250° C. was measured, based upon which the percent weight loss was calculated. The percent weight loss for each of the compositions is given in Table 1.

(24) Measurement Conditions and Apparatus Measurement apparatus: VPE-9000 SP Saturated Vapor Pressure Evaluation System (Ulvac-Riko, Inc.) Measurement atmosphere: open air Measurement temperature: 250° C. Measurement time: 1 hour

(25) TABLE-US-00001 TABLE 1 Composition Percent weight loss (%) 1-1 32 1-2 15 1-3 8 1-4 3 2-1 3 3-1 2 4-1 35 4-2 17 4-3 10 4-4 8 5 15 6 4 7 5 8 4

Examples 1 to 6, Comparative Examples 1 to 8

(26) Preparation of Water/Oil Repellent Treatment Agents

(27) Water/oil repellent treatment agents were prepared by dissolving the respective above compositions in ethyl perfluorobutyl ether (Novec 7200, from 3M) to a solids concentration of 20 wt %.

(28) Formation of Cured Film

(29) The respective water/oil repellent treatment agents were applied by vacuum deposition under the conditions indicated below onto a piece of glass (50 mm×100 mm) having a 10 nm surface most layer of vapor-deposited SiO.sub.2 (Gorilla® Glass 2, from Corning Inc.). In each case, the treatment was cured for 1 hour at 120° C. to form a cured coat.

(30) Coating Conditions and Apparatus Coating apparatus: Small vacuum system for vapor deposition VPC-250 F Pressure: 2.0×10.sup.−3 Pa to 3.0×10.sup.−2 Pa Deposition temperature (ultimate temperature of boat): 500° C. Source-to-substrate distance: 20 mm Weight of treatment supplied: 10 mg Deposited weight: 10 mg

(31) The water repellency, abrasion resistance, mold release properties and dynamic coefficient of friction for the resulting cured coats were evaluated by the following methods. Each test, both initially and after one hour of heating at 250° C., was carried out in a 25° C., 50% humidity environment. The results are shown in Table 2, together with the compositions within the water/oil repellent treatment agents.

(32) Evaluation of Water Repellency

(33) The contact angle of the cured coat with water (droplet size: 2 μL) was measured using a DropMaster contact angle meter (Kyowa Interface Science Co., Ltd.).

(34) Evaluation of Abrasion Resistance

(35) The abrasion resistance to steel wool (#0000) was evaluated by measuring the water contact angle in the same way as described above after 2,000 rubbing cycles using a TriboGear 30S Friction Tester (Shinto Scientific Co., Ltd.).

(36) Surface area of contact: 1 cm.sup.2

(37) Load: 1 kg

(38) Evaluation of Mold Release Properties

(39) The peel strength was measured under the following conditions using the Autograph® AG-IS (Shimadzu Corporation).

(40) Pressure-sensitive adhesive treatment: Nitto No. 31B (width, 19 mm; from Nitto Denko Corporation)

(41) Pressure bonding conditions: 20 g/cm.sup.2 load

(42) Aging: 25° C./24 hours

(43) Peel rate: 300 mm/min, 180° direction

(44) Evaluation of Dynamic Coefficient of Friction

(45) The dynamic coefficient of friction with respect to a Bemcot™ (Asahi Kasel Corporation) wipe was measured under the following conditions using a 14FW Surface Property Tester (Shinto Scientific Co., Ltd.).

(46) Surface area of contact: 10 mm×35 mm

(47) Load: 100 g

(48) TABLE-US-00002 TABLE 2 Water Mold contact Abrasion release Dynamic angle resistance properties coefficient (degrees) (degrees) (N/19 mm) of friction After After After After Composition Initial heating Initial heating Initial heating Initial heating Example 1 1-3 116 115 110 111 0.05 0.05 0.03 0.03 2 1-4 115 114 111 110 0.04 0.04 0.03 0.03 3 2-1 115 115 113 113 0.05 0.05 0.03 0.03 4 3-1 115 115 114 112 0.04 0.05 0.03 0.03 5 6 115 111 111 110 0.05 0.05 0.03 0.03 6 8 115 110 110 112 0.04 0.05 0.04 0.03 Comparative 1 1-1 116 115 110 85 0.04 0.10 0.03 0.05 Example 2 1-2 115 114 111 98 0.04 0.08 0.03 0.04 3 4-1 115 97 110 58 0.04 0.25 0.03 0.18 4 4-2 115 98 110 82 0.04 0.22 0.03 0.15 5 4-3 115 105 110 85 0.05 0.20 0.03 0.14 6 4-4 115 106 110 78 0.05 0.21 0.03 0.15 7 5 115 110 110 96 0.05 0.11 0.03 0.14 8 7 115 98 98 95 0.05 0.05 0.03 0.03

(49) From the above results, in Comparative Examples 1 and 2, low-boiling components evaporated off during heating at 250° C., leading to a decline in the abrasion resistance after heating. In Comparative Examples 3 to 6, because the linkage group Q was —CF.sub.2—CH.sub.2—O—C.sub.3H.sub.6—, deterioration due to heating at 250° C. occurred. This gave rise to, after heating, a decline in the water contact angle, a decline in the abrasion resistance, a rise in peel strength and a rise in the dynamic coefficient of friction. By contrast, in Examples 1 to 3 according to the invention, it was possible to retain the properties (water contact angle, abrasion resistance, mold release properties, dynamic coefficient of friction) even after heating at 250° C. Even in Example 4, in which purification to remove low-boiling components was carried out on an intermediate product, excellent properties comparable with those in Examples 1 to 3 were obtained.

(50) In Comparative Example 7, the nonfunctional polymer was not thin-film distilled, as a result of which low-boiling components evaporated off during heating at 250° C., leading to a decrease in the abrasion resistance after heating. In Comparative Example 8, the content of nonfunctional polymer was high, resulting in a poor abrasion resistance. By contrast, in Examples 5 and 6 according to the invention, it was possible to retain the properties (water contact angle, abrasion resistance, mold release properties, dynamic coefficient of friction) even after heating at 250° C.

(51) The inventive water/oil repellent treatment agent which contains a fluorooxyalkylene group-containing polymer-modified silane and/or a partial hydrolyzate/condensate thereof, or which contains both this and also a fluorooxyalkylene group-containing polymer, does not incur changes in water/oil repellency, abrasion resistance, mold release properties and dynamic coefficient of friction even when heated at 250° C. Hence, following film formation on a substrate, this treatment is able to retain its performance even on passing through processes at temperatures of 250° C. or more. The water/oil repellent treatment agent of the invention is thus exceedingly useful, particularly in applications such as touch panel displays and anti-reflective coatings on which finger oils are likely to adhere yet for which visibility is important. The inventive treatment is also useful as a mold release agent in thermal imprinting and the like.

(52) Japanese Patent Application No. 2014-232583 is incorporated herein by reference.

(53) Although some preferred embodiments have been described, many modifications and variations may be made thereto in light of the above teachings. It is therefore to be understood that the invention may be practiced otherwise than as specifically described without departing from the scope of the appended claims.