WO2019026816A1 - Fluorine-containing composite particles - Google Patents

Abstract

Provided are fine particles that can exhibit higher water repellency and higher oil repellency than conventional ones. The present invention pertains to fluorine-containing composite particles obtained by coating the surface of silica fine particles with at least one of 1) a fluorine-containing compound and 2) a fluorine-containing group formed by siloxane bonding between the fluorine-containing compound and silicon in the silica fine particles, wherein (1) the fluorine-containing compound includes a functional group represented by [-Si(OR)3] (wherein, three Rs may be the same or different and each represent hydrogen or a C1-10 alkyl group) at at least one end of the main chain of perfluoropolyether, and (2) the fluorine content per unit surface area of the silica fine particles is 0.8 mg/m2 to 1.0 g/m2.

Description

Fluorine-containing composite particles

The present invention relates to a novel fluorine-containing composite particle, and more particularly to a composite particle having anti-adhesion properties (water and oil repellency).

In recent years, materials that exhibit water repellency or oil repellency have attracted attention from the viewpoint of antifouling properties, reduction of the frictional resistance at the solid-liquid interface, and the like. For example, Patent Document 1 discloses a coating film provided with metal oxide composite particles provided with a resin layer containing a polyfluoroalkyl methacrylate resin on the surface.

JP, 2014-80465, A

However, although conventional techniques such as the technique of Patent Document 1 can provide high water repellency and oil repellency to water or most oils, oil repellency (oleophobicity) is satisfactory for fatty acids such as oleic acid, for example. There is room for further improvement in that respect.

Therefore, an object of the present invention is to provide fine particles capable of exhibiting higher water repellency and oil repellency than conventional ones.

As a result of intensive studies in view of the problems of the prior art, the present inventor has found that the above object can be achieved by adopting a specific particle structure, and has completed the present invention.

That is, the present invention relates to a fluorine-containing composite particles below.
1. A composite particle in which the surface of a silica-based fine particle is coated with at least one of 1) a fluorine-containing compound and 2) a fluorine-containing group formed by siloxane bond with silicon of the silica-based fine particle,
The fluorine-containing compound is at least one distally [-Si (OR) 3] in the main chain of perfluoropolyether _(provided that three R are the same or different from each other, 1 hydrogen or carbon atoms 10 And the fluorine-containing amount per unit surface area of the silica-based fine particles is 0.9 mg / m ² to 1.0 g / m ^2. Fluorine-containing composite particles.
2. Wherein the fluorine-containing compound has a number average molecular weight of 500-2500, the fluorine-containing composite particles of the claim 1, wherein.
3. The average primary particle diameter of 3 ~ 50 [mu] m, the fluorine-containing composite particles according to any one of the claim 1 or 2.
4. The functional group at one end of the polymer and the functional group at the other end from the side to which the silica particle is bonded are [--Si (OR) of the polymer having another perfluoropolyether as the main chain _3] (provided that the three R are the same or different from each other, represent hydrogen or an alkyl group having 1 to 10 carbon atoms.) is bonded to the functional group represented by, according to any one of the items 1 to 3 Fluorine-containing composite particles.
5. The fluorine-containing compound _{(RO) 3 Si- (CH 2} ) k -NHC (= O) -CF 2 -O- (C n F 2n) m -C (= O) NH- (CH 2) k -Si _{(oR) 3} (where, R represents an alkyl group having 1 to 4 carbon atoms, n represents 1-7 integer, m is an integer of seven or more, k is an integer of 1 to 5 respectively.) the compound represented by the comprising fluorine-containing composite particles according to any one of the claim 1-4.

ADVANTAGE OF THE INVENTION According to this invention, the microparticles | fine-particles which can exhibit water repellency and oil repellency higher than before can be provided. In particular, the fluorine-containing composite particles of the present invention can exhibit high oil repellency even to fatty acids. In particular, high oil repellency (antifouling) can be obtained even with higher fatty acids such as palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid.

For this reason, the fluorine-containing composite particles of the present invention can be suitably applied to products, members, parts and the like for which an adhesion preventing effect (water and oil repellency) is required.

FIG. 1 (a) is a schematic view of a laminate formed by laminating a coating film comprising the fluorine-containing composite particles of the present invention on a substrate. FIG. 1 (b) shows a schematic view of the structure of the fluorine-containing composite particle of the present invention. FIG. 2 is a schematic view of an apparatus used to measure a sliding angle in a test example. Fig.2 (a) shows the state before jacking up a glass board. FIG.2 (b) shows the state which jacked up the glass board.

1. Fluorine-containing composite particles
Fluorine-containing composite particles of the present invention (the invention particles), the surface of the silica-based fine particles 1) fluorine-containing compound and 2) it is coated with at least one silicon and siloxane bonds to become a fluorine-containing groups of the silica-based particles The composite particles being
(1) the fluorine-containing compound, at least one end side to [-Si (OR) 3] in the main chain of perfluoropolyether _(provided that three R are the same or different from each other, hydrogen or carbon atoms represents 1 to 10 alkyl group.) also referred to as functional group (hereinafter "functional group a" represented by.) is a compound containing,
(2) Fluorine content per unit surface area of the silica fine particles are ^{0.8mg / m 2 ~ 1.0g / m} 2,
It is characterized by

A schematic view of the particles of the present invention is shown in FIG. 1 (b). The particles 26 of the present invention have a structure in which a part or the whole of the surface is coated with a fluorine-containing compound (or a fluorine-containing group) 28 using the silica-based fine particles 27 as core particles. That is, the coating layer containing the fluorine-containing compound (or the fluorine-containing group) 28 is formed on the surface of the core particle. As the fluorine-containing compound, polymers having perfluoropolyether as a main chain (in particular, linear polymers) can be suitably used. In the present invention, the fluorine-containing compound 28 may be present on the surface of the silica-based fine particle without reaction (that is, while maintaining the functional group A), but in particular, the functional group A is present on the surface of the silica-based fine particle As a result of forming a chemical bond (in particular, a siloxane bond) with a certain silica or another functional group (in particular, a hydrophilic group such as an OH group), it is preferable to exist as a fluorine-containing group (a fluorine-containing organic group). As a result, the fluorine-containing compound can be more firmly fixed to the surface of the silica-based fine particle as a fluorine-containing group.

Silica-Based Fine Particles The silica-based fine particles may be any particles containing silica (SiO ₂ ), and may be particles containing silica and other components in addition to particles consisting of silica alone. In the present invention, the silica based particles, silica is preferably fine particles containing more than 50 wt%, preferably microparticles particularly containing silica 99% by mass or more.

When the silica-based fine particles contain other components, the other components include, in addition to unavoidable impurities, for example, iron (Fe), titanium (Ti), aluminum (Al), calcium (Ca), zirconium (Zr), sodium Elements such as (Na), potassium (K), magnesium (Mg) and the like or compounds thereof can be mentioned.

Furthermore, since the silica-based fine particles may be obtained by surface treatment of the silica particles, the compound (or functional group) provided by the surface treatment may be included. Therefore, in the present invention, hydrophobic silica-based particles, hydrophilic silica-based particles or a mixture thereof can be used as the silica-based particles.

In the present invention, as the silica-based fine particles, it is possible to use hydrophilic silica particles having an OH group on the surface thereof suitably. By providing the OH groups on the surface of the silica-based fine particles, a siloxane bonding functional group A is a dehydration condensation reaction with OH groups of the silica-based fine particle surface ^{[-Si-O-Si *]} ( where, Si ^* in the silica-based particles forming a Si) contained, a fluorine-containing compound to the silica-based fine particle surface can be firmly fixed.

In addition, even when hydrophobic silica-based particles and the like are used, hydrophilic silica-based particles are used by applying hydrophilic treatment to hydrophobic silica-based particles in advance to impart OH groups and the like to the surface of the silica-based particles. As in the case, it becomes possible to fix the fluorine-containing compound on the surface of the silica-based fine particles.

The average primary particle size of the silica-based particles is usually 3 to 500 nm, and preferably 10 to 300 nm. By setting the particle diameter in the above range, more excellent water repellency and oil repellency can be obtained.

In the present invention, the measurement of the primary particle average diameter of the particles can be carried out using a transmission electron microscope or a scanning electron microscope. More specifically, the average primary particle size is determined by photographing with a transmission electron microscope or scanning electron microscope, measuring the diameters of 200 or more particles on the photograph, and calculating the arithmetic mean value be able to.

No particular limitation is imposed on the specific surface area of the silica-based fine particles, usually preferably not more than 400 meters ² / g, it is preferable in particular 10 ~ 380m ² / g. When the specific surface area exceeds 400 m ² / g, it becomes difficult to uniformly coat a fluorine compound or a fluorine-containing group described later, which may lower the yield. The specific surface area can be determined by BET1 point method using a Macsorb (manufactured MOUNTECH). Adsorption gas, using nitrogen 30 vol% helium 70% by volume of the gas, for 10 minutes at 100 ° C. as a pretreatment of the sample, after the flow of adsorbed gas, the cell containing the sample was cooled with liquid nitrogen, increased to room temperature after the adsorption completion raised, determined the surface area of the sample from the desorbed amount of nitrogen can be obtained a specific surface area by dividing the mass of the sample.

The shape of the silica-based fine particles is not particularly limited as long as it is in the form of particles, and any shape such as spherical, rod-like, needle-like, plate-like, indeterminate, scaly and spindle-like can be adopted. In particular, the silica-based fine particles are preferably spherical (substantially spherical) close to a true sphere in order to minimize the contact area with water or oil.

As these silica-based fine particles themselves, known or commercially available ones can also be used. Moreover, it is also possible to synthesize | combine by a well-known manufacturing method. Therefore, for example, silica-based particles produced by high-temperature combustion of silane tetrachloride, silica-based particles produced by a sol-gel method, and the like can be suitably used. As a commercial product, for example, product name "AEROSIL 200" ("AEROSIL" is a registered trademark. The same applies to the following), "AEROSIL 130", "AEROSIL 300", "AEROSIL 50", "AEROSIL 200 FAD", "AEROSIL 380" (or more) In addition to Nippon Aerosil Co., Ltd., “SO-01” (manufactured by Admatex Co., Ltd.) and the like can be mentioned.

Fluorine-containing compounds present on the surface of the fluorine-containing compound silica-based fine particles, at least one of the distal [-Si (OR) 3] in the main chain of perfluoropolyether _(wherein, R represents hydrogen or a carbon number 1 an alkyl group of 1-10.) is a compound containing a functional group represented by.

In the present invention, as described above, a polymer having a perfluoropolyether as a main chain can be used. By using a polymer having such a perfluoropolyether as the main chain, it is possible to secure a chain length equivalent to C8 or more without including a C8 fluorotelomer (C8 telomer) like structure that may cause environmental pollution. High water repellency and oil repellency can be obtained. In addition, the presence of an ether bond in the main chain makes it possible to firmly coat the surface of the silica-based fine particle.

As the fluorine-containing compound used in the present invention, more specifically the following general formula (1):
_{X-CF 2 -O- (C n} F 2n O) m-CF 2 -X ··· (1)
It can be suitably used compound represented by in.

In the above general formula, X is a terminal portion containing an alkoxysilane functional group [—Si (OR) ₃ ], and a perfluoropolyether having a functional group A can also be referred to as a perfluoropolyether silane.

Further, n and m in the above general formula are independent natural numbers, and the values thereof are not particularly limited. In particular, n is preferably 1 or more and 7 or less. m is preferably 7 or more and 100 or less. By setting it in such a range, the fine particles in which the surface of the silica-based fine particles is coated with the above-mentioned fluorine compound can exhibit high water repellency and oil repellency.

The functional group A in the fluorine-containing compound, as described above [-Si _(OR) 3] (provided that the three R are the same or different from each other, represent hydrogen or an alkyl group having 1 to 10 carbon atoms.) In It is a functional group represented.

In particular, when R is an alkyl group, it is preferably an alkyl group having 1 to 10 carbon atoms (in particular, a linear alkyl group), and more preferably an alkyl group having 1 to 4 carbon atoms. As such an alkyl group, a methyl group, an ethyl group, a propyl group or a butyl group is mentioned, for example.

In addition, all three Rs of the functional group A may be different, or some or all of them may be the same. When at least one of the three OR groups in the functional group is bonded to the silicon of the silica-based particles, it can be a fluorine-containing group and can be strongly linked to the silica-based particles. More preferably, if two or all of the OR groups of the above functional groups are bonded to the silica-based fine particles, the immobilization can be performed more strongly.

In particular, X in the above general formula may contain the functional group A. Therefore, all X may be a functional group A, or a part of X may be another functional group as long as the effects of the present invention are not impaired.

Furthermore, the functional group A may be directly bonded to the main chain [—CF ₂ —O— (CF ₂ O) _p — (CF ₂ CF ₂ O) _q —CF ₂ —] consisting of perfluoropolyether and, it may be bonded via a linker unit. Linker unit is for connecting the CF ₂ and a functional group A particular in the general formula of the perfluoropolyether described above. As such a linker moiety, for example, oxyalkylene group [-O-R ¹ -O-] (R ¹ represents an alkylene group), ether bond [-O-], ester bond [-C (= O) O-], an amide bond [-CONH-], include a urethane bond [-COHN-O-] and the like.

In the present invention, in particular for reasons such that the synthesis is easy, the linker portion is preferably comprising an amide bond (-CONH-). Further, -C a linker moiety _{(= O) NH- (CH 2} ) k - and more preferably contains. That, X in the general formula of the perfluoropolyether described above, for example, _{-C (= O) NH- (CH} 2) k -Si (OR) is preferably _3.

Accordingly, a suitable perfluoropolyether as the polymer main chain, the following general formula (2):
_{(RO) 3 Si- (CH 2} ) k -NHC (= O) -CF 2 -O- (CF 2 O) p - (CF 2 CF 2 O) q -CF 2 -C (= O) NH- ( _{CH 2) k -Si (OR)} 3 ··· (2)
In the fluorine-containing compounds represented.

Here, k, p and q are natural numbers that independently. Preferably the value of k is 1-6, or more preferably 2-3. If the value of k exceeds 6, it is difficult to coat the fluorine-containing compound to the silica fine particle surface. the sum of p and q correspond to m in Formula _{X-CF 2 -O- (C n} F 2n O) m -CF 2 -X. Further, _(CF 2 O) and _(CF 2 _CF 2 O) is obtained by the n = 1 and n = 2 respectively in the general formula.

The molecular weight of the polymer having a perfluoropolyether which is a fluorine-containing compound as a main chain is not particularly limited, but a number average molecular weight measured by gel permeation chromatography is preferably 500 to 5000, and particularly preferably 1000 to 3000, Among these, 1200 to 2500 are most preferable. When the number average molecular weight exceeds 5,000, it may be difficult to dissolve the polymer in a water-soluble organic solvent. If the polymer can not be dissolved in a water-soluble organic solvent, for example, when R of the functional group A is an alkyl group, the hydrolysis reaction for substituting the OR group with an OH group becomes difficult to proceed. If the OR group can not be substituted with an OH group, formation of a siloxane bond between the functional group A and the OH group on the surface of the silica-based fine particle does not proceed as described later, and the polymer is firmly bonded to the surface of the silica-based particle and coated. It becomes difficult. In addition, if any of the OR groups can not be substituted with OH groups, dehydration condensation reaction between the functional groups A of the multiple polymers does not easily occur. As a result, the polymers are less likely to become long-chained and water repellency and oil repellency decrease. There is a fear.

The application amount (coating amount) of the coating layer (fluorine-containing compound) is not limited, but is 0.8 mg / m ² or more and 1.0 g / m ² or less as the fluorine content per unit surface area of the silica-based fine particles, preferably a 0.9 mg / ^{m 2} or more 1.5 mg / ^{m 2} or less. Is less than 0.9 mg / ^{m 2,} sometimes water repellency and oil repellency are insufficient. If it exceeds 1.0 g / ^{m 2,} the processing cost becomes high.

The fluorine content, the fluorine content per unit mass of the present invention particles F (g / g) BET specific surface area of the silica-based fine particles S ^(m 2 / g) divided by the value F / S (g / ^{m 2} ). Here, the fluorine content F are quartz tube combustion decomposition - is a value measured by an ion chromatographic method. More specifically, burned in a quartz combustion tube the sample was heated to 900 ~ 10000 ° C., the resulting gas was collected by steam distillation, it detects the recovering solution as fluoride ion by ion chromatography, quantified that Accordingly, the total fluorine content determined, which can be calculated by dividing the mass of the sample.

2. Method for producing fluorine-containing composite particles
Method for producing a fluorine-containing composite particles is not particularly limited. For example, using the silica-based fine particles of the fluorine-containing compound, a method known coating, the coating layer comprising a fluorine-containing compound may be formed on the silica-based fine particle surface according to granulation methods and the like. In particular, it is possible to suitably prepare the present invention particles by a manufacturing method comprising the step (coating step) of mixing a solution of the silica-based particles or the dispersion liquid and a fluorine-containing compound thereof.

The silica-based fine particles may be mixed with the solution of the fluorine-containing compound as it is, but it is preferable to mix with the solution in the form of a dispersion in that higher dispersibility is obtained. That is, a dispersion in which silica-based particles are dispersed in a solvent can be suitably used.

As the solvent in this case, any solvent can be used as long as the silica-based fine particles do not dissolve or deteriorate. For example, other than water, aromatic hydrocarbons such as toluene and xylene, alicyclic hydrocarbon solvents such as methylcyclohexane and cyclohexane, ester solvents such as ethyl acetate and butyl acetate, ketone solvents such as methyl ethyl ketone and acetone Organic solvents such as alcohol solvents such as isopropyl alcohol and denatured ethanol can be used. In particular, any of water, a water-soluble organic solvent or a mixed solvent thereof can be suitably used. The water-soluble organic solvent is not limited, and examples thereof include methanol, ethanol, 2-propanol, propylene glycol monomethyl ether and the like.

The content of the silica-based fine particles in the dispersion may be usually set in the range of about 1 to 50% by weight from the viewpoint of the dispersibility of the silica-based fine particles in the dispersion, but is not limited thereto.

Moreover, a pH adjuster can also be mix | blended with a dispersion liquid as needed. As a pH adjuster, acids such as acetic acid and hydrochloric acid, and bases such as sodium hydroxide and ammonia can be used.

The solution of the fluorine-containing compound can be prepared by dissolving the fluorine-containing compound in a solvent.

As the fluorine-containing compound, the above-mentioned 1. The compound shown by can be used suitably. In this case, it is more preferable to use a fluorine-containing compound in which at least one of the three Rs of the functional group A is hydrogen (H) as the fluorine-containing compound used as a raw material. The OH group is contained in the functional group on the terminal side of at least one end of the polymer having a perfluoropolyether main chain, thereby forming a siloxane bond with the OH group on the surface of the silica-based fine particle, thereby forming a silica bond It is easy to firmly bond and coat the polymer. Furthermore, by having an OH group at the end of the polymer, a siloxane bond (that is, a fluorine-containing group) can be formed by dehydration condensation reaction with the OH group on the surface of the silica-based fine particle without using a water-soluble organic solvent. it can.

In addition, even if all of the functional groups A of the fluorine-containing compound used as the raw materials are alkyl groups, the water-soluble organic solvent is used in the coating step to cause water to be present to cause the OR group to undergo a hydrolysis reaction. It is converted into an OH group, and a siloxane bond can be formed by a dehydration condensation reaction with the OH group on the surface of the silica-based fine particle. As a result, the fluorine-containing compound can be strongly fixed to the surface of the silica-based fine particle as a fluorine-containing group.

The polymer may have a functional group A on one end side, but more preferably has a functional group A on both end sides. By having the functional group A on both terminal sides of the polymer, in some polymers, both terminals are bonded to the silica-based fine particles to be in a more rigid state. In some polymers, one end is bonded to the silica-based fine particle, and the other end is bonded to the other polymer end to form a long chain. Therefore, as a result of the area of the perfluoropolyether occupying on the surface of the silica-based fine particles, it becomes possible to express higher water repellency and oil repellency.

As the solvent in the solution, particularly, water, a water-soluble organic solvent or a mixed solvent thereof can be suitably used. The water-soluble organic solvent is not particularly limited as long as it is a solvent miscible with water such as methanol, ethanol, 2-propanol, propylene glycol monomethyl ether and the like. As described above, the reaction in an aqueous system makes it possible to form a siloxane bond more reliably as described above.

The content of the fluorine-containing compound in the solution of the fluorine-containing compound is not particularly limited, but generally 10 to 80% by weight, in particular 15 to 70% by weight, and further preferably 20 to 60% by weight. Is preferred.

When mixing a silica-based fine particle or a dispersion thereof with a solution of a fluorine-containing compound, the ratio of the silica-based fine particle to the solution may be appropriately set according to the coating amount of the desired fluorine-containing compound. It is preferable to adjust so that it may become the shown coating amount.

Moreover, in the present invention, it is preferable to further include a step of stirring the mixed solution after particularly mixing both. By stirring the mixed solution, it becomes possible to fully react part or all of the functional group A with the silica on the surface of the silica-based fine particle or the functional group on the silica surface to reliably form a siloxane bond.

The stirring conditions are not particularly limited as long as they are not higher than the boiling point of the solvent that occupies the majority in the solution. For example, the stirring temperature is usually about 30 to 80 ° C., preferably 40 to 70 ° C. The stirring time is usually about 1 to 96 hours, preferably 6 to 84 hours. Stirring may be performed using a commercially available stirring device.

After the stirring is completed, the particles of the present invention can be obtained in the form of a slurry. For this reason, when using this invention particle | grains for a predetermined use, it can be used in the form of a slurry as it is. In addition, after processing such as solid-liquid separation, washing, etc. is performed to the above-mentioned slurry as needed, it can also be used in the form of a substantially dried powder. The powder can also be used in the form of a dispersion obtained by dispersing it in a solvent. In addition, it is also possible to use in the form of a dispersion obtained by dispersing the slurry obtained by solid-liquid separation of the slurry in a separate solvent.

3. Using the present invention the particles of the fluorine-containing composite particles, by applying to various articles, it is possible to impart desired repellency and / or oil repellency. In particular, by forming a coating film comprising the present invention particles to the article surface, it is possible to impart water repellency and / or oil repellency.

There are no particular limitations on the material that is the object of forming the coating (that is, the object of imparting water repellency and oil repellency). The material may be, for example, metal, plastics, ceramics, rubber, fibrous materials (paper, non-woven fabric, woven fabric, etc.), composite materials of these materials, etc. Moreover, it may be any of a product, a semi-finished product, or their raw materials.

More specifically, as the materials (products, etc.), in addition to packaging materials, daily necessities (glasses, rain gear, eyebrows, etc.), building materials (roof, wallpaper, flooring, ceiling materials, tiles, window glass, etc.), dishes, cooking Appliances (pots, saucepans for gas stoves, oil panels, top plates of induction cookers, etc.), kitchenware, sports goods, clothing (hats, shoes, gloves, coats, etc.), structures (building walls, bridges, The present invention can be widely applied to transportation equipment (car, motorcycle, train, ship, etc. body outer surface), cosmetics, medicines, toys, jigs for identification, etc.

In the present invention, in particular, a packaging material is suitable as the material. The packaging material also includes both a package as a product (finished product) and its raw material. Examples of the product (finished product) include a lid of a container, and a package such as a molded container, a wrapping paper, a tray, a tube, and a bag (a pouch or the like). Moreover, as a raw material of a package body, the laminated body containing a base material and a heat seal layer, etc. can be mentioned, for example. That is, the packaging material comprised from the laminated body which contains in order 1) the water-repellent and oil-repellent coating film which contains this invention particle | grains, 2) heat seal layer, and 3) base material layer can be illustrated. As long as the water repellent and oil repellent coating film is disposed on the outermost surface of the laminate, another layer may be further laminated.

The schematic diagram of the cross section of the laminated body containing the coating film by this invention particle | grains is shown to Fig.1 (a). As shown in FIG. 1A, in the laminate 1, the particles 26 of the present invention are laminated on the surface of a substrate 10. Furthermore, the schematic diagram of the cross section of this invention particle | grains 26 is shown in FIG.1 (b). As shown in FIG. 1B, the fluorine-containing compound 26 coats the surface of the silica-based particles 27 with the silica-based particles 26 coated with the fluorine compound. In FIG. 1, the structure is schematically illustrated in an easily understandable manner, and the size, the number, and the like of each configuration do not necessarily reproduce the actual laminate.

Examples and comparative examples are shown below, and the features of the present invention are more specifically described. However, the scope of the present invention is not limited to the examples.

Example 1
Hydrophilic BET value 200 meters ² / g silica fine particles 3.0 g (Nippon Aerosil Co., AEROSIL200, average primary particle diameter = 12 nm) in ethanol solvent (Godo Co. GS Arco EP-7) was dispersed in 62.6g The This was followed by acetic acid 0.4g and pure water 10.0g was added, and stirred for 3 minutes with a glass rod, to prepare a dispersion.
Separately from this, the average of the perfluoropolyether silane (p + q of the following formula in a concentration of 10 mass% (3) is 14, the number average molecular weight 2000, k is 3, R is an ethyl group shown.) prepared 2.4 g, was mixed with ethanol solvent 21.6 g, was prepared perfluoropolyether silane ethanol solution.

_{(RO) 3 Si- (CH 2} ) k -NHC (= O) -CF 2 -O- (CF 2 O) p - (CF 2 CF 2 O) q C (= O) NH- (CH 2) k -Si (OR) ₃
... (3)

Then added perfluoropolyether silane ethanol 24.0g, prepared the dispersion was stirred for 3 minutes with a glass rod. The mixed slurry thus obtained is stirred at 50 ° C. for 3 days, and the fluorine compound-coated fine particles (fluorine-containing composite particles, fluorine content per unit surface area (F / S) = 1.1 mg / m ² A coating solution containing
Thereafter, the resulting coating solution to form a coating film with. After diluting the coating solution with an ethanol-based solvent (GS Alco EP-7 manufactured by Godo Co., Ltd.) so that the target lamination amount of the silica-based fine particles coated with the fluorine compound after drying is 1.2 g / m ² , the bar The surface of a commercially available slide glass (MICRO SLIDE GLASS S9213) was coated using a coater # 6. Next, it was heated and dried in an oven at 180 ° C. for 10 seconds to evaporate the ethanol-based solvent. There was thus prepared a sample of the laminate.

Example 2
BET value ^16m 2 / g of the hydrophilic silica fine particles 3.0 g (Admatechs Co., SO-C1, average primary particle diameter = 250 nm) and, dispersed in ethanol solvent (Godo Co. GS Arco EP-7) 62.6 g I did. This was followed by acetic acid 0.4g and pure water 10.0g was added, and stirred for 3 minutes with a glass rod, to prepare a dispersion.
Separately from this, the average of the perfluoropolyether silane (p + q of the following formula in a concentration of 10 mass% (3) is 14, the number average molecular weight 2000, k is 3, R is an ethyl group shown.) prepared 0.2 g, was mixed with ethanol solvent 1.8g, was prepared perfluoropolyether silane ethanol solution.

_{(RO) 3 Si- (CH 2} ) k -NHC (= O) -CF 2 -O- (CF 2 O) p - (CF 2 CF 2 O) q C (= O) NH- (CH 2) k -Si (OR) ₃
... (3)

Then added perfluoropolyether silane ethanol solution 2.0g, prepared the dispersion was stirred for 3 minutes with a glass rod. The mixed slurry thus obtained was stirred for 3 days under the conditions of 50 ° C., the fluorine compound-coated microparticles (fluorine-containing composite particles, the fluorine content per unit surface area (F / S) = 1.3mg / m 2 A coating solution containing Using the obtained coating solution, samples were prepared similarly laminate as in Example 1.

Example 3
Perfluoropolyether silane 1.8g, except for using the perfluoropolyether silane ethanol solution 18g prepared using ethanol solvent 16.2g, the same procedure as in Example 1, the fluorine compound-coated microparticles (fluorine-containing composite particles, fluorine content per unit surface area coating solution containing (F / S) = 0.9mg / m 2) was prepared. Using the obtained coating solution was prepared sample of the laminate in the same manner.

Comparative Example 1
Silica fine particles (trade name "AEROSIL200" manufactured by Nippon Aerosil Co., Ltd., BET specific surface area: 200m ² / g, average primary particle size 12 nm) 5 g was placed in a reaction vessel, commercially available surface treatment agent while stirring in a nitrogen gas atmosphere spray 500 g, then 200 after stirring for 30 min at ° C., and cooled. This gave a fluorine compound-coated microparticles (fluorine content per unit surface area (F / S) = 0.4mg / m 2).
Incidentally, as the surface treatment agent of the polyfluoro octyl methacrylate, 2-N, N-diethylaminoethyl methacrylate, 2-hydroxyethyl methacrylate and 2,2'-ethylenedioxy aqueous dispersion of a copolymer of diethyl dimethacrylate (solids Concentration: 20% by weight) was used.
It was prepared coating liquid The surface modified silica fine particles are dispersed in ethanol 100 ml. As in Example 1 by using the obtained coating liquid was manufactured a sample of the laminate.

Comparative example 2
Perfluoropolyether silane 1.2g, except for using the perfluoropolyether silane ethanol solution 12g adjusted using ethanol solvent 10.8g, the same procedure as in Example 1, the fluorine compound-coated microparticles (fluorine-containing composite particles, fluorine content per unit surface area coating solution containing (F / S) = 0.7mg / m 2) was prepared. As in Example 1 by using the obtained coating liquid was manufactured a sample of the laminate.

Comparative example 3
_{CF 3 (CF 2) 3 (} CH 2) 2 OH ( product name "FA-4" UNIMATEC Ltd. (Ltd.)) 0.25 g was added and dissolved in methanol 30 ml, silica sol (product name into the solution " methanol silica sol; 30 wt% nano silica containing "manufactured by Nissan chemical Co.) 1.67 g and tetraethoxysilane (trade name" Dynasylan a "Evonik Japan Ltd.) 0.25 ml was added, while stirring with a magnetic stirrer , added 25 wt% aqueous ammonia 0.25 ml, the reaction was carried out for 5 hours. After completion of the reaction, the methanol was removed and aqueous ammonia under reduced pressure using an evaporator, redispersed overnight resulting powder in methanol of approximately 20 ml. Centrifuged using the next day centrifuge tube, the supernatant discarded, the new methanol were added thereto to carry out a rinsing operation. After three times this rinse work, the mouth of the centrifuge tube covered with aluminum foil, and placed overnight in a 70 ℃ of oven. The next day and dried for overnight 50 ° C. a vacuum dryer to obtain a white powder. A coating solution was prepared by dispersing 5.0 g of the fluorine-containing nanosilica composite particles before firing obtained in 95.0 g of an ethanol-based solvent (GS Alco EP-7 manufactured by Gordo). As in Example 1 by using the obtained coating liquid was manufactured a sample of the laminate.

Test Example 1
It was measured sliding angle at 25 ° C. for a sample of the resulting laminate in each of Examples and Comparative Examples. The results are shown in Table 1.
As the measurement method of the sliding angle using the apparatus shown in FIG. As shown in FIG. 2 (a), an electric lab jack 30 (manufactured by Auto Lab jacks ALJ200-H, AS ONE Corporation), established the foundation 20, so as to extend over the electric laboratory jack 30 and the base 20, 30 cm × 70cm × Place the glass plate 36 of 3 mm, further digital angle meter 38 (digital goniometer mini DPM-1, Toei Kogyo Co., Ltd.) in a plate 36 carrying the. At this time, turn on the digital angle meter 38, the plate 36 is adjusted lifting height of the electric lab jack 30 so that the horizontal (inclination 0 °).
The side 32 of the plate 36 in contact with the base 20 and the base 20 were fixed with a commercially available tape so that the plate 36 does not move in the horizontal direction. On the other hand, the side is supported by an electric lab jack 30 of the plate 36 was not fixed.
Thus, as shown in FIG. 2 (b), the electric lab jack 30 when jacked up, the plate 36 and Kosudo while always in contact with the upper end portion 34 of the electric lab jack 30 a plate 36 is inclined. And one side 32 of the plate 36 which is fixed a base 20, and the distance Y between the upper portion 34 of the electric lab jack 30 and 50 cm.
It was then placed in a surface in which fine particles are coated with the laminate 1 obtained in Examples and Comparative Examples to the plate 36 coating solution was layered on top. Paste the commercial tape at the four corners of the laminated body 1, and fixed to the plate 36.
Thereafter, the micropipette tip 40 (Ibis pipet tip, manufactured by Ibis) was attached to a micropipette (pipetman P20, manufactured by GILSON), 20 μl of the sample 42 was weighed out, and the sample 42 was dropped gently on the laminate 1. Here, as sample 42, pure water, oleic acid (NAA-34, manufactured by NOF Corporation, content: 98 mass% or more as fatty acid) and edible olive oil (AJINOMOTO olive oil) were used respectively.
Then, the electric lab jack 30 was jacked up at a speed of 1 cm / sec, the plate 36 was inclined, and when it was confirmed that the sample 42 was visually rolled off, the jack up was stopped and displayed on the digital angle meter 38 the angle was recorded as the sliding angle.
In each of Examples and Comparative Examples, each measured 5 times for each sample was determined sliding angle of the mean. The results are shown in Table 1. In addition, even if the plate 36 was inclined to 45 degrees, the jackup was stopped at 45 degrees when the part or all of the sample did not roll while adhering to the laminate 1.

As shown in Table 1, the sliding angle of water showed a very small sliding angle in both Example 1 and Comparative Example 1, but the sliding angle of oleic acid and olive oil in Example 1 was the comparative example. The sliding angle was much smaller than 1. Thus, it can be seen that the fluorine-containing composite particles of the present invention can exhibit high oil repellency also to higher fatty acids such as oleic acid as well as specific oil components such as olive oil and the like.

Claims (5)

1. A composite particle in which the surface of a silica-based fine particle is coated with at least one of 1) a fluorine-containing compound and 2) a fluorine-containing group formed by siloxane bond with silicon of the silica-based fine particle,
   (1) the fluorine-containing compound, at least one end side to [-Si (OR) 3] in the main chain of perfluoropolyether _(provided that three R are the same or different from each other, hydrogen or carbon atoms a compound containing a functional group represented by an alkyl group having 1 to 10.),
   (2) Fluorine content per unit surface area of the silica fine particles are ^{0.8mg / m 2 ~ 1.0g / m} 2,
   Fluorine-containing composite particles, characterized in that.
2. The fluorine-containing composite particle according to claim 1, wherein the number average molecular weight of the fluorine-containing compound is 500 to 2,500.
3. The fluorine-containing composite particle according to claim 1, wherein the average primary particle diameter is 3 to 500 nm.
4. The functional group at one end of the polymer and the functional group at the other end from the side to which the silica particle is bonded are [--Si (OR) of the polymer having another perfluoropolyether as the main chain _3. The fluorine-containing composite according to claim 1, wherein the fluorine-containing complex is bonded to a functional group represented by the formula ₃ ] (provided that three R's are the same or different and each represents hydrogen or an alkyl group having 1 to 10 carbon atoms). particle.
5. The fluorine-containing compound _{(RO) 3 Si- (CH 2} ) k -NHC (= O) -CF 2 -O- (C n F 2n) m -C (= O) NH- (CH 2) k -Si _{(oR) 3} (where, R represents an alkyl group having 1 to 4 carbon atoms, n represents 1-7 integer, m is an integer of seven or more, k is an integer of 1 to 5 respectively.) the compound represented by the comprising fluorine-containing composite particles according to claim 1.

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