KR20190113787A - Water repellent powder - Google Patents

Abstract

In the infrared absorption spectrum measured using Fourier transform infrared spectroscopy, Si-CH ₃ when the peak intensity of wave number 1070 cm ^-1 derived from the network structure of Si-O-Si bond is defined as 1.0 is 1.0. It is related with the water-repellent powder whose peak intensity of 1270 cm <^-1> vicinity derived from a structure is 0.2-0.7.

Description

Water repellent powder

The present disclosure relates to water repellent powder.

Conventionally, imparting water-repellent performance to substrates having transparency such as glass and plastics products has been required for many products in order to minimize the adhesion of water droplets and to secure a watch. Usually, a water repellent performance is obtained by forming a film (henceforth "water repellent film") with the coating material excellent in water repellency on the surface of a base material. The water-repellent film generally refers to a film in which the contact angle of water becomes 90 ° or more.

As a material for forming the water repellent film, polytetrafluoroethylene (PTFE) and its derivatives are known. However, since the temperature for curing PTFE is several hundred degrees or more, the application point and the substrate are limited.

Further, Patent Documents 1 and 2 describe forming a water repellent film using a fluoroalkylsilane.

Japanese Unexamined Patent Publication No. 2002-105661 Japanese Unexamined Patent Publication No. 2000-81214

Since the water repellent film formed from fluoroalkylsilane is not enough adhesiveness with respect to a base material, it is difficult to apply a fluoroalkylsilane to a base material, and to form a water repellent film excellent in flexibility. Therefore, there is a demand for a water repellent material having excellent flexibility while maintaining water repellency.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a water-repellent powder having excellent water repellency and flexibility.

MEANS TO SOLVE THE PROBLEM As a result of earnestly researching in order to achieve the said objective, when the water-repellent powder which has a specific silicon-bonding unit, it discovered that the outstanding water repellency and flexibility were expressed, and came to completion of this invention.

In one aspect, the present invention provides a peak intensity of a wavelength of 1070 cm ^-1 derived from a network structure of a Si-O-Si bond in a infrared absorption spectrum measured using Fourier transform infrared spectroscopy as 1.0. To provide a water-repellent powder having a peak intensity of 0.2 to 0.7 around a wavenumber of 1270 cm ^-1 derived from the Si-CH ₃ structure.

In another aspect, the present invention is derived from Q and T when the silicon-containing bonding units Q, T and D are defined as follows in the solid ²⁹ Si-NMR spectrum measured using the DD / MAS method. It is to provide the water-repellent powder whose ratio Q + T: D of a signal area and the signal area derived from D is 1: 0.01-1: 0.5. However, below, an organic group is a monovalent organic group whose atom couple | bonded with the silicon atom is a carbon atom.

Q: A silicon-containing bond unit having four oxygen atoms bonded to one silicon atom.

T: A silicon-containing bonding unit having three oxygen atoms bonded to one silicon atom and one hydrogen atom or monovalent organic group.

D: A silicon-containing bonding unit having two oxygen atoms bonded to one silicon atom and two hydrogen atoms or monovalent organic groups.

In another aspect, the present invention provides a water-repellent powder having a structure represented by the following General Formula (1).

[Formula 1]

[In formula (1), R <^1> and R <^2> represents an alkyl group or an aryl group each independently, and R <^3> and R <^4> represents a alkylene group each independently.]

In another aspect, the present invention provides a water repellent powder having a ladder structure including a support portion and a crosslinking portion, wherein the crosslinking portion is represented by the following General Formula (2).

[Formula 2]

[In formula (2), R <^5> and R <^6> represents an alkyl group or an aryl group each independently, and b shows the integer of 1-50.]

From the viewpoint of further improving the water repellency and flexibility, the water repellent powder may have a ladder structure represented by the following general formula (3).

[Formula 3]

[In formula (3), R <^5> , R <^6>, R <^7> and R <^8> represent an alkyl group or an aryl group each independently, a and c respectively independently represent the integer of 1-3000, b is an integer of 1-50 Is displayed.]

From a viewpoint of improving the formation property and adhesiveness of the water repellent film with respect to the to-be-processed surface, 1-1000 micrometers may be sufficient as average particle diameter D50 of a water repellent powder.

According to the present invention, it is possible to provide a water repellent powder excellent in water repellency and flexibility. Since the water repellent powder of this invention can provide water repellency to a to-be-processed surface at low temperature, it can provide excellent water repellency to the object which does not have heat resistance. Moreover, since this water repellent powder is excellent in flexibility, it is excellent in adhesiveness to a target object and can maintain the function of water repellency for a long time.

FIG. 1: is a figure which shows an example of the solid ²⁹ Si-NMR spectrum of the water repellent powder of this embodiment.
2 is a diagram illustrating a method for calculating the biaxial average primary particle diameter of particles.
3 is a diagram showing an infrared absorption spectrum of the water repellent powder prepared in Examples and Comparative Examples.

EMBODIMENT OF THE INVENTION Hereinafter, preferred embodiment of this invention is described in detail, referring drawings as needed. However, this invention is not limited to the following embodiment.

<Definition>

In this specification, the numerical range shown using "-" shows the range which includes the numerical value described before and after "-" as minimum value and the maximum value, respectively. In the numerical range described step by step in this specification, the upper limit or the lower limit of the numerical range of any step may be replaced by the upper limit or the lower limit of the numerical range of another step. In the numerical range described in this specification, you may substitute the upper limit or the lower limit of the numerical range by the value shown in the Example. "A or B" should just contain either A and B, and may include both. The material illustrated in this specification can be used individually by 1 type or in combination of 2 or more type, unless there is particular notice. In this specification, content of each component in a composition means the total amount of the some substance which exists in a composition, when there exists a plurality of substances corresponding to each component in a composition, unless there is particular notice.

<Specific aspect of water-repellent powder>

As water-repellent powder of this embodiment, the following 1st-5th aspect is mentioned. By employ | adopting the 1st-5th aspect, it becomes easy to make compatible the water repellency and flexibility of a water repellent powder. Moreover, by employ | adopting each aspect, the water repellent powder which has water repellency and flexibility according to each aspect can be obtained. In addition, in this embodiment, a water repellent powder says "the granular body which has a porous structure."

(1st aspect)

The water-repellent powder of the present embodiment, when the peak intensity of the wave number of 1070 cm ^-1 derived from the network structure of the Si-O-Si bond is defined as 1.0 in the infrared absorption spectrum measured using Fourier transform infrared spectroscopy, wave number 1270 ㎝ vicinity ^-1 derived from Si-CH ₃ structure (e.g., the wave number range of 1280 ~ 1260 ㎝ ^-1) or may be the peak intensity of the, water-repellent powder, 0.2 to 0.7. 0.2-0.6 may be sufficient as the peak intensity of 1270 cm <^-1> vicinity, and 0.2-0.5 may be sufficient as it. The art as the peak intensity of 0.2 or more, it is possible to impart excellent water repellency derived from Si-CH ₃ structure, and, as being less than 0.7, it is possible to obtain excellent flexibility derived from a siloxane skeleton.

The infrared absorption spectrum of the water repellent powder can be measured by a Fourier transform infrared spectrometer, and in particular, it is measured with better precision by a total reflection measurement method (ATR method) using diamond as a transparent high refractive index medium (prism) in the infrared region. can do. Although it does not specifically limit to the kind of infrared spectrometer to be used, For example, FT-IR / 6300 (made by Nippon spectroscopy), ALPHA compact FT-IR (made by Brooker Optics, Inc.) etc. can be used.

(2nd aspect)

The water-repellent powder of this embodiment can contain polysiloxane which has a principal chain containing a siloxane bond (Si-O-Si). The water repellent powder may have the following M unit, D unit, T unit, or Q unit as a structural unit.

[Formula 4]

In said formula, R represents a monovalent organic group. M unit is a unit which consists of monovalent groups which the silicon atom couple | bonded with one oxygen atom. D unit is a unit which consists of a bivalent group which the silicon atom couple | bonded with two oxygen atoms. T unit is a unit which consists of a trivalent group which the silicon atom couple | bonded with three oxygen atoms. Q unit is a unit which consists of a tetravalent group which the silicon atom couple | bonded with four oxygen atoms. Information about the content of these units can be obtained by Si-NMR.

The water-repellent powder of the present embodiment has a signal area derived from Q and T when the silicon-containing bonding units Q, T and D are defined as follows in the solid ²⁹ Si-NMR spectrum measured using the DD / MAS method. And water-repellent powder whose ratio Q + T: D of the signal area derived from D is 1: 0.01-1: 0.50 may be sufficient.

Q: A silicon-containing bond unit having four oxygen atoms bonded to one silicon atom.

T: A silicon-containing bonding unit having three oxygen atoms bonded to one silicon atom and one hydrogen atom or monovalent organic group.

D: A silicon-containing bonding unit having two oxygen atoms bonded to one silicon atom and two hydrogen atoms or monovalent organic groups.

The ratio Q + T: D of the signal area derived from Q and T and the signal area derived from D may be set to 1: 0.01 to 1: 0.45, or may be set to 1: 0.02 to 1: 0.40. When the signal area ratio is set to 1: 0.01 or more, the water repellency tends to be more easily obtained, and the ratio of 1: 0.50 or less tends to be more flexible. By including the signal area ratio Q + T: D in this range, the water repellency and flexibility can be further improved.

The "oxygen atom" in Q, T and D is an oxygen atom which mainly bonds between two silicon atoms, For example, the case where it is an oxygen atom which the hydroxyl group couple | bonded with the silicon atom has can also be considered. Moreover, "organic" is a monovalent organic group whose atom couple | bonded with the silicon atom is a carbon atom, For example, a C1-C10 unsubstituted or substituted monovalent organic group is mentioned. As an unsubstituted monovalent organic group, hydrocarbon groups, such as an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an aryl group, an aralkyl group, are mentioned, for example. Moreover, as a substituted monovalent organic group, the hydrocarbon group (substituted organic group) in which the hydrogen atom of these hydrocarbon groups was substituted by the halogen atom, the predetermined | prescribed functional group, the predetermined functional group containing organic group, etc., especially a cycloalkyl group, an aryl group, an aralkyl group The hydrocarbon group in which the hydrogen atom of such rings was substituted by the alkyl group is mentioned. As a halogen atom, a chlorine atom, a fluorine atom, etc. (that is, it becomes halogen atom substituted organic groups, such as a chloroalkyl group and a polyfluoroalkyl group), As a functional group, a hydroxyl group, a mercapto group, a carboxyl group, Epoxy group, amino group, cyano group, acryloyloxy group, and methacryloyloxy group are mentioned, As a functional group containing organic group, an alkoxy group, acyl group, acyloxy group, alkoxycarbonyl group, glycidyl group, epoxy A cyclohexyl group, an alkylamino group, a dialkylamino group, an arylamino group, and an N-aminoalkyl substituted aminoalkyl group are mentioned.

The signal area ratio can be confirmed by solid ²⁹ Si-NMR spectrum. Generally, the measurement method of solid ²⁹ Si-NMR is not specifically limited, For example, although the CP / MAS method and the DD / MAS method are mentioned, in this embodiment, the DD / MAS method is employ | adopted from a quantitative viewpoint. .

The chemical shifts of the silicon-bonded units Q, T and D in the solid ²⁹ Si-NMR spectrum are Q units: -90 to -120 ppm, T units: -45 to -80 ppm, D units: 0 to -40 Since it is observed in the range of ppm, respectively, it is possible to isolate | separate the signal of silicon-bonding unit Q, T, and D, and to calculate the signal area derived from each unit. In the case of spectral analysis, an exponential function can be employed as the Window function from the viewpoint of improving the analysis accuracy, and the line broadening coefficient can be set within the range of 0 to 50 Hz.

FIG. 1: is a figure which shows an example of the solid ²⁹ Si-NMR spectrum of the water repellent powder of this embodiment measured using the DD / MAS method. As shown in FIG. 1, the signal of the silicon-bonding units Q, T, and D can be separated by solid ²⁹ Si-NMR using the DD / MAS method.

Here, the calculation method of signal area ratio is demonstrated using FIG. For example, in FIG. 1, the Q unit signal derived from silica is observed in the chemical shift range of -90-120 ppm. Moreover, in the chemical shift range of -45-80 ppm, the signal of the T unit derived from a polysiloxane compound and a trimethoxysilane reactant is observed. And in the chemical shift range of 0-40 ppm, the signal of the D unit derived from the polysiloxane compound and the dimethyldimethoxysilane reactant is observed. The signal area (integrated value) is obtained by integrating the signal in each chemical shift range. When the sum of the signal areas of the Q unit and the T unit is 1, the signal area ratio Q + T: D of FIG. 1 is calculated to be 1: 0.13. In addition, a signal area can be computed using general spectral analysis software (For example, NMR software "TopSpin" (TopSpin registered trademark) by Bruker Corporation).

(Third aspect)

The water repellent powder of this embodiment can have a structure represented by following General formula (1).

[Formula 5]

The water repellent powder of this embodiment may have a structure represented by following General formula (1a) as a structure containing the structure represented by Formula (1).

[Formula 6]

In formulas (1) and (1a), R ¹ and R ² each independently represent an alkyl group or an aryl group, and R ³ and R ⁴ each independently represent an alkylene group. Here, as an aryl group, a phenyl group and a substituted phenyl group are mentioned, for example. As a substituent of a substituted phenyl group, an alkyl group, a vinyl group, a mercapto group, an amino group, a nitro group, and a cyano group are mentioned, for example. P shows the integer of 1-50 in a formula (1a). In formula (1a), two or more R <^1> may be the same or different, and similarly, two or more R <^2> may be the same or different, respectively. In formula (1a), two R <^3> may be same or different, respectively, and similarly, two R <^4> may be same or different, respectively.

From the viewpoint of further improving the water repellency and flexibility of the water repellent powder, in the formula (1) and the formula (1a), each of R ¹ and R ² may be an alkyl group having 1 to 6 carbon atoms or a phenyl group independently. The alkyl group may be a methyl group. In formulas (1) and (1a), R ³ and R ⁴ may each independently be an alkylene group having 1 to 6 carbon atoms. The alkylene group may be an ethylene group or a propylene group. P can be 2-30 in formula (1a), and 5-20 may be sufficient.

(Fourth aspect)

The water repellent powder of the present embodiment may be a water repellent powder having a ladder structure having a support portion and a crosslinked portion, and the water repellent powder having a structure represented by the following general formula (2) may be used. By introducing such a ladder structure into the skeleton of the water repellent powder, the water repellency and flexibility can be improved. In addition, in this embodiment, a "ladder type structure" is what has a bridges which connect two struts and struts (so-called "ladder" form). In this aspect, although the skeleton which forms a water repellent powder may have a ladder structure, the water repellent powder may have a ladder structure partially.

[Formula 7]

In formula (2), R <^5> and R <^6> represents an alkyl group or an aryl group each independently, and b shows the integer of 1-50. Here, as an aryl group, a phenyl group and a substituted phenyl group are mentioned, for example. As a substituent of a substituted phenyl group, an alkyl group, a vinyl group, a mercapto group, an amino group, a nitro group, and a cyano group are mentioned, for example. In addition, in formula (2), when b is an integer greater than or equal to 2, two or more R <^5> may be the same respectively and may differ, and similarly two or more R <^{6> may} respectively be same or different.

Moreover, the conventional ladder silsesquioxane has a structure represented by the following general formula (X), and the structure of a crosslinking part is -O-. On the other hand, in the water-repellent powder of this embodiment, the structure of a crosslinked part is a structure (polysiloxane structure) represented by the said General formula (2).

[Formula 8]

In formula (X), R represents a hydroxyl group, an alkyl group, or an aryl group.

Although the space | interval of the structure used as a support part, its chain length, and the structure used as a bridge | crosslinking part is not specifically limited, From a viewpoint of improving water repellency and flexibility further, as a ladder type structure, the ladder type structure represented by following General formula (3) is shown. Can be mentioned.

[Formula 9]

In formula (3), R <^5> , R <^6> , R <^7> and R <^8> represent an alkyl group or an aryl group each independently, a and c respectively independently represent the integer of 1-3000, b represents the integer of 1-50 Indicates. Here, as an aryl group, a phenyl group and a substituted phenyl group are mentioned, for example. As a substituent of a substituted phenyl group, an alkyl group, a vinyl group, a mercapto group, an amino group, a nitro group, and a cyano group are mentioned, for example. In the formula (3), when b is an integer of 2 or more, two or more R ⁵ may be the same or different, and similarly, two or more R ⁶ may be the same or different, respectively. In the formula (3), when a is an integer of 2 or more, two or more R ⁷ may be the same or different, respectively. Similarly, when c is an integer of 2 or more, two or more R ⁸ may be the same or different, respectively.

From the viewpoint of obtaining more flexibility, in formulas (2) and (3), R ⁵ , R ⁶ , R ⁷ and R ⁸ (wherein R ⁷ and R ⁸ are only in formula (3)) are each independently An alkyl group or phenyl group having 1 to 6 carbon atoms may be used. The alkyl group may be a methyl group. In Formula (3), a and c can respectively be 6-2000 independently, and 10-1000 may be sufficient. In formula (2) and formula (3), b may be 2-30, and 5-20 may be sufficient.

(Fifth aspect)

The water-repellent powder of this embodiment consists of a polysiloxane compound which has a hydrolysable functional group or a condensable functional group, and the hydrolysis product (polysiloxane compound which the hydrolyzable functional group hydrolyzed) of the polysiloxane compound which has a hydrolysable functional group. What is obtained by drying the wet gel produced | generated from the sol containing at least 1 sort (s) of compound chosen from a group (henceforth called "polysiloxane compound group") may be sufficient. That is, the water-repellent powder of this embodiment contains the polysiloxane compound which has a hydrolysable functional group or a condensable functional group, and contains at least 1 sort (s) of compound chosen from the group which consists of a hydrolysis product of the polysiloxane compound which has a hydrolysable functional group. The dried product of the wet gel which is a condensate of a sol may be sufficient. In addition, the water-repellent powder described so far is also at least one selected from the group consisting of a hydrolyzable product of a polysiloxane compound having a hydrolyzable functional group or a condensable functional group and a polysiloxane compound having a hydrolyzable functional group. What is obtained by drying the wet gel produced | generated from the sol containing these may be sufficient.

The hydrolyzable functional group and the condensable functional group in the polysiloxane compound are not particularly limited. As a hydrolysable functional group, an alkoxy group is mentioned, for example. As a condensable functional group (except the functional group corresponding to a hydrolysable functional group), a hydroxyl group, a silanol group, a carboxyl group, a phenolic hydroxyl group, etc. are mentioned. The hydroxyl group may be contained in hydroxyl group containing groups, such as a hydroxyalkyl group. In addition, the polysiloxane compound having a hydrolyzable functional group or a condensable functional group further contains a reactive group (a functional group not corresponding to a hydrolyzable functional group and a condensable functional group) different from the hydrolyzable functional group and the condensable functional group. You may have it. As a reactive group, an epoxy group, a mercapto group, glycidoxy group, a vinyl group, acryloyl group, methacryloyl group, an amino group, etc. are mentioned. The epoxy group may be contained in epoxy group containing groups, such as glycidoxy group. These polysiloxane compounds which have a functional group and a reactive group may be used individually or in mixture of 2 or more types. Among these functional groups and reactive groups, the alkoxy group, silanol group, and hydroxyalkyl group can further improve the compatibility of the sol. In addition, the carbon number of the alkoxy group and the hydroxyalkyl group can be 1 to 6 from the viewpoint of improving the reactivity of the polysiloxane compound and the wear resistance of the water repellent powder, but from 2 to 4 in view of further improving the wear resistance of the water repellent powder. You may also

As a polysiloxane compound which has a hydroxyalkyl group, the compound which has a structure represented by following General formula (A) is mentioned, for example. By using the polysiloxane compound which has a structure represented by following General formula (A), the structure represented by the said General formula (1) and (1a) can be introduce | transduced in the skeleton of water-repellent powder.

[Formula 10]

In formula (A), R ^1a represents a hydroxyalkyl group, R ^2a represents an alkylene group, R ^3a and R ^4a each independently represent an alkyl group or an aryl group, and n represents an integer of 1 to 50. Here, as an aryl group, a phenyl group and a substituted phenyl group are mentioned, for example. As a substituent of a substituted phenyl group, an alkyl group, a vinyl group, a mercapto group, an amino group, a nitro group, and a cyano group are mentioned, for example. In formula (A), two R <^1a> may be same or different, respectively, and similarly, two R <^2a> may be same or different, respectively. In Formula (A), two or more R <^3a> may be same or different, and similarly, two or more R <^4a> may be same or different, respectively.

By using the wet gel (wet gel produced from the sol) which is a condensate of the sol containing the polysiloxane compound of the above structure, a water-repellent powder having excellent flexibility can be more easily obtained. From the same point of view, the following features may be satisfied. In formula (A), as R <^1a> , a C1-C6 hydroxyalkyl group is mentioned, for example, A hydroxyethyl group and a hydroxypropyl group are mentioned specifically ,. In formula (A), as R <^2a> , a C1-C6 alkylene group is mentioned, for example, Ethylene group and a propylene group are mentioned specifically ,. In formula (A), R <^3a> and R <^4a> may respectively independently be a C1-C6 alkyl group or a phenyl group. The alkyl group may be a methyl group. In formula (A), n can be 2-30 and 5-20 may be sufficient.

As a polysiloxane compound which has a structure represented by the said General formula (A), a commercial item can be used, For example, compounds, such as X-22-160AS, KF-6001, KF-6002, KF-6003 (all, Shin-Etsu) Chemical Industry Co., Ltd.), and compounds (all are manufactured by Momentive), such as XF42-B0970 and Fluid OFOH 702-4%, are mentioned.

As a polysiloxane compound which has an alkoxy group, the compound which has a structure represented by following General formula (B) is mentioned, for example. By using the polysiloxane compound which has a structure represented by following General formula (B), the ladder type structure containing the crosslinked part which has a structure represented by the said General formula (2) can be introduce | transduced in the skeleton of water-repellent powder.

[Formula 11]

In formula (B), R ^1b represents an alkyl group, an alkoxy group or an aryl group, R ^2b and R ^3b each independently represent an alkoxy group, R ^4b and R ^5b each independently represents an alkyl group or an aryl group, and m is 1 to 1 The integer of 50 is shown. Here, as an aryl group, a phenyl group and a substituted phenyl group are mentioned, for example. As a substituent of a substituted phenyl group, an alkyl group, a vinyl group, a mercapto group, an amino group, a nitro group, and a cyano group are mentioned, for example. In addition, in Formula (B), two R <^1b> may be same or different, respectively, two R <^2b> may be same or different, respectively, and similarly, two R <^3b> may be same or different, respectively. In the formula (B), when m is an integer of 2 or more, two or more R ^4b may be the same or different, and similarly, two or more R ^5b may be the same or different, respectively.

By using the wet gel which is a condensate of the sol containing the polysiloxane compound of the said structure or its hydrolysis product, water-repellent powder excellent in flexibility becomes easy to be obtained more. From the same point of view, the following features may be satisfied. In formula (B), as R <^1b> , a C1-C6 alkyl group and a C1-C6 alkoxy group are mentioned, for example, A methyl group, a methoxy group, and an ethoxy group are mentioned specifically ,. In formula (B), R ^2b and R ^3b may each independently be an alkoxy group having 1 to 6 carbon atoms. As this alkoxy group, a methoxy group and an ethoxy group are mentioned, for example. In formula (B), R ^4b and R ^5b may be each independently an alkyl group having 1 to 6 carbon atoms or a phenyl group. The alkyl group may be a methyl group. M can be 2-30 in a formula (B), and 5-20 may be sufficient.

The polysiloxane compound which has a structure represented by the said General formula (B) can be obtained by referring suitably the manufacturing method reported by Unexamined-Japanese-Patent No. 2000-26609, Unexamined-Japanese-Patent No. 2012-233110, etc., for example.

Moreover, since an alkoxy group hydrolyzes, the polysiloxane compound which has an alkoxy group may exist as a hydrolysis product in a sol, The polysiloxane compound which has an alkoxy group, and its hydrolysis product may be mixed. Moreover, in the polysiloxane compound which has an alkoxy group, all the alkoxy groups in a molecule may be hydrolyzed, and may be partially hydrolyzed.

The polysiloxane compound which has a hydrolysable functional group or a condensable functional group, and the hydrolysis product of the polysiloxane compound which has a hydrolysable functional group may be used individually or in mixture of 2 or more types.

In manufacturing the water-repellent powder of the present embodiment, the sol containing the polysiloxane compound or the hydrolyzate thereof may contain a silicon compound (except the polysiloxane compound) other than the polysiloxane compound. That is, the sol according to the present embodiment is at least one selected from the group consisting of a silane monomer having a hydrolyzable functional group or a condensable functional group, and a hydrolysis product of a silane monomer having a hydrolyzable functional group (hereinafter, May be further called "silane monomer group". The silicon number in a molecule | numerator in a silane monomer can be 1-6.

Although it does not specifically limit as a silane monomer which has a hydrolysable functional group, For example, alkyl silicon alkoxide is mentioned. Among the alkyl silicon alkoxides, those having three or less hydrolyzable functional groups can further improve water resistance. As an alkyl silicon alkoxide, a monoalkyl trialkoxysilane, a monoalkyl dialkoxysilane, a dialkyl dialkoxysilane, a monoalkyl monoalkoxy silane, a dialkyl monoalkoxysilane, and a trialkyl monoalkoxysilane are mentioned, for example. Examples of the alkyl silicon alkoxides include methyltrimethoxysilane, methyldimethoxysilane, dimethyldimethoxysilane, and ethyltrimethoxysilane.

Although it does not specifically limit as a silane monomer which has a condensable functional group, For example, a silane tetraol, a methyl silane triol, a dimethyl silandiol, a phenyl silan triol, a phenyl methyl silandiol, a diphenyl silandiol, n-propyl Silane triol, hexyl silane triol, octyl silane triol, decyl triane and trifluoropropyl silane triol.

The silane monomer which has a hydrolysable functional group or a condensable functional group may further have the above-mentioned reactive group different from a hydrolysable functional group and a condensable functional group. As the silane monomer having a number of hydrolysable functional groups of 3 or less and having a reactive group, vinyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-methacryl Oxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, N- Phenyl-3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, etc. can also be used.

As a silane monomer which has a condensable functional group and has the above-mentioned reactive group, vinylsilane triol, 3-glycidoxy propyl silan triol, 3-glycidoxy propylmethyl silandiol, 3-methacryloxypropyl silane triol , 3-methacryloxypropylmethylsilanediol, 3-acryloxypropylsilanetriol, 3-mercaptopropylsilanetriol, 3-mercaptopropylmethylsilanediol, N-phenyl-3-aminopropylsilanetriol, N-2- (aminoethyl) -3-aminopropylmethylsilanediol and the like can also be used.

As the silane monomer having three or less hydrolysable functional groups at the molecular end, bistrimethoxysilylmethane, bistrimethoxysilylethane, bistrimethoxysilylhexane, and the like can also be used.

The silane monomer which has a hydrolysable functional group or a condensable functional group, and the hydrolysis product of the silane monomer which has a hydrolysable functional group may be used individually or in mixture of 2 or more types.

In addition, content of the polysiloxane compound group contained in the said sol (total content of the polysiloxane compound which has a hydrolysable functional group or condensable functional group, and content of the hydrolysis product of the polysiloxane compound which has a hydrolysable functional group), It can be 5 mass parts or more with respect to 100 mass parts of total amounts of a sol, and 10 mass parts or more may be sufficient. The said content can be 50 mass parts or less with respect to 100 mass parts of total amounts of a sol, and may be 30 mass parts or less. That is, although content of a polysiloxane compound group can be 5-50 mass parts with respect to 100 mass parts of total amounts of a sol, you may further be 10-30 mass parts. When the content is made 5 parts by mass or more, good reactivity is more easily obtained, and when it is 50 parts by mass or less, good compatibility is further easily obtained.

When the sol further contains a silane monomer group, the content of the polysiloxane compound group, the content of the silane monomer group (content of the silane monomer having a hydrolyzable functional group or a condensable functional group, and a hydrolyzable functional group) The ratio of the total content of the hydrolysis product of the silane monomer to have) can be 1: 0.5 to 1: 4, but may be 1: 1 to 1: 2. By setting the ratio of the content of these compounds to 1: 0.5 or more, good compatibility is more easily obtained, and by setting it to 1: 4 or less, it is easy to further suppress the shrinkage of the gel.

The sum total of content of a polysiloxane compound group and a silane monomer group may be 5 mass parts or more with respect to 100 mass parts of total amounts of a sol, and 10 mass parts or more may be sufficient as it. The sum total of the said content can be 50 mass parts or less with respect to 100 mass parts of total amounts of a sol, and may be 30 mass parts or less. That is, although the sum total of content of a polysiloxane compound group and a silane monomer group can be 5-50 mass parts with respect to 100 mass parts of total amounts of a sol, you may further be 10-30 mass parts. When the sum total of the said content is 5 mass parts or more, favorable reactivity will be easy to be acquired more, and if it is 50 mass parts or less, favorable compatibility will become easier to be obtained further. Under the present circumstances, ratio of content of a polysiloxane compound group and a silane monomer group can be in the said range.

The sol which concerns on this embodiment may contain the silica particle further. That is, the water repellent powder of this embodiment may further have a structure based on a silica particle. As a silica particle, it can use without a restriction | limiting especially, For example, an amorphous silica particle is mentioned. As amorphous silica particle, a fused silica particle, a fumed silica particle, and a colloidal silica particle are mentioned, for example. Among them, the colloidal silica particles have high monodispersity and are easy to suppress aggregation in the wet gel formation step of the water repellent powder. The silica particles may be silica particles having a hollow structure or a porous structure.

The shape of the silica particles is not particularly limited, and examples thereof include spherical, cocoon and associative. Among these, by using spherical particles as silica particles, it becomes easy to suppress aggregation in the wet gel formation step of the water repellent powder. The average primary particle size of the silica particles may be 1 nm or more, 5 nm or more, for example, from the viewpoint of easily obtaining a water-repellent powder having an appropriate hardness and easily improving durability against heat shock and scratches. Nm or more may be sufficient. The average primary particle size of the silica particles may be, for example, 200 nm or less, 150 nm or less, or 100 nm or less from the viewpoint of easily obtaining transparent water repellent powder. From these viewpoints, an average primary particle diameter of a silica particle may be 1-200 nm, 5-150 nm may be sufficient, and 20-100 nm may be sufficient.

In addition, about a silica particle, it is possible to measure an average particle diameter from a raw material. For example, the biaxial average primary particle diameter is computed as follows from the result of having observed 20 arbitrary particle | grains by SEM. In other words, using colloidal silica particles having a solid content concentration of 5 to 40% by mass, which is usually dispersed in water, a chip obtained by cutting a wafer having a pattern wiring in a dispersion of colloidal silica particles 2 cm in width and width about 30 cm is used. After soaking for seconds, the chip is rinsed in pure water for about 30 seconds and dried with nitrogen blow. Thereafter, the chip is placed on the sample stage for SEM observation, the acceleration voltage is applied at 10 mA, the silica particles are observed at a magnification of 100,000 times, and an image is taken. Twenty silica particles are arbitrarily selected from the obtained image, and the average of the particle diameters of these particles is taken as the average particle diameter. At this time, when the selected silica particle was in the shape as shown in FIG. 2, it circumscribes to silica particle P and induces the rectangle (external rectangle L) arrange | positioned so that the long side may become longest. Then, the long side of the circumscribed rectangle L is X, the short side is Y, and (X + Y) / 2 is used to calculate the biaxial average primary particle size, and the particle size of the particle is obtained.

The number of silanol groups per 1 g of the silica particles may be 10 × 10 ¹⁸ / g or more, for example, from the viewpoint of having good reactivity and easily giving excellent water repellency and flexibility at low temperature and in a short time, 10 ¹⁸ piece / g or more may be sufficient and 100 * 10 <^18> piece / g or more may be sufficient. The number of silanol groups per 1 g of the silica particles is easy to suppress the rapid gelation in the wet gel formation step of the water repellent powder, from the viewpoint of obtaining a homogeneous water repellent powder, for example, 1000 × 10 ¹⁸ / g It may be less than 800 * 10 <^18> / g, and may be 700 * 10 <^18> / g or less. From these viewpoints, the number of silanol groups per 1g of silica particles may be 10 * 10 <^18> -1000 * 10 <^18> pieces / g, 50 * 10 <^18> -800 * 10 <^18> pieces / g may be sufficient, for example, 100 × 10 ¹⁸ ~ 700 × 10 may be a ¹⁸ / g.

Content of the said silica particle contained in the sol which concerns on this embodiment is 0.01 mass part with respect to 100 mass parts of total amounts of a sol from a viewpoint that the reactivity of the wet gel in the wet gel formation process of a water-repellent powder improves, for example, 0.01 It may be at least mass parts, may be at least 0.1 mass parts, or may be at least 0.5 mass parts. Even if the content of the said silica particle is easy to obtain the water-repellent powder of moderate hardness, and durability to heat shock and abrasion is easy to improve, it is 30 mass parts or less with respect to 100 mass parts of total amounts of a sol, for example. 20 mass parts or less may be sufficient, and 10 mass parts or less may be sufficient. From these viewpoints, although content of a silica particle can be 0.01-30 mass parts with respect to 100 mass parts of total amounts of a sol, 0.1-20 mass parts may be sufficient and 0.5-10 mass parts may be sufficient.

<Method for producing water repellent powder>

Next, the manufacturing method of a water repellent powder is demonstrated. Although the manufacturing method of a water repellent powder is not specifically limited, For example, it can manufacture by the following method.

That is, the water-repellent powder of this embodiment is a process for pulverizing the wet gel obtained in the sol generating step, the wet gel producing step of gelling the sol obtained in the sol generating step, and then aging to obtain the wet gel, and the wet gel producing step. It can manufacture by the manufacturing method mainly equipped with the wet gel grinding process, the process of washing and solvent-substituting the wet gel particle obtained by the wet gel grinding process, and the drying process of drying the wash | cleaning and solvent-substituted wet gel particle. In addition, a sol is a state before a gelation reaction arises, and in this embodiment, the said polysiloxane compound group and the silane monomer group in some cases mean the state melt | dissolved or disperse | distributed in a solvent. In addition, a wet gel means the gel solid of the wet state which contains a liquid medium but does not have fluidity.

Hereinafter, each process of the manufacturing method of the water repellent powder of this embodiment is demonstrated.

(Sol generation process)

A sol formation process is a process of mixing and hydrolyzing the polysiloxane compound mentioned above, a silane monomer, a silica particle, and a solvent as needed, and generating a sol. In this step, an acid catalyst may be further added to the solvent in order to promote the hydrolysis reaction. In addition, as disclosed in Japanese Patent No. 5250900, a surfactant, a thermohydrolyzable compound, or the like may be added to the solvent.

As the solvent, for example, water or a liquid mixture of water and alcohols can be used. Examples of the alcohols include methanol, ethanol, n-propanol, 2-propanol, n-butanol, 2-butanol and t-butanol. Among these, methanol, ethanol, 2-propanol, etc. are mentioned as alcohol which is easy to reduce interface tension with a gel wall, and has low surface tension and low boiling point. You may use these individually or in mixture of 2 or more types.

For example, when alcohols are used as the solvent, the amount of alcohols may be 4 to 8 moles with respect to 1 mole of the total amount of the polysiloxane compound group and the silane monomer group, but may be 4 to 6.5 moles, or 4.5 to 6 moles. You may make it a mole. By setting the amount of alcohols to 4 mol or more, good compatibility is more easily obtained, and by setting it to 8 mol or less, the shrinkage of the gel can be further suppressed.

As an acid catalyst, For example, inorganic acids, such as hydrofluoric acid, hydrochloric acid, nitric acid, sulfuric acid, sulfurous acid, phosphoric acid, phosphorous acid, hypophosphoric acid, bromic acid, chloric acid, a chlorochloric acid, hypochlorous acid; Acidic phosphates such as acidic aluminum phosphate, acidic magnesium phosphate and acidic zinc phosphate; And organic carboxylic acids such as acetic acid, formic acid, propionic acid, oxalic acid, malonic acid, succinic acid, citric acid, malic acid, adipic acid and azelaic acid. Among these, organic carboxylic acid is mentioned as an acid catalyst which improves the water resistance of the water repellent powder obtained further. Although acetic acid is mentioned as organic carboxylic acids, formic acid, propionic acid, oxalic acid, malonic acid, etc. may be sufficient. You may use these individually or in mixture of 2 or more types.

By using an acid catalyst, hydrolysis reaction of a polysiloxane compound and a silane monomer can be accelerated | stimulated, and a sol can be obtained in a shorter time.

The addition amount of an acid catalyst can be 0.001-0.1 mass part with respect to 100 mass parts of total amounts of a polysiloxane compound group and a silane monomer group.

As surfactant, nonionic surfactant, an ionic surfactant, etc. can be used. You may use these individually or in mixture of 2 or more types.

As a nonionic surfactant, the compound containing the hydrophilic part, such as a polyoxyethylene, and a hydrophobic part mainly consisting of an alkyl group, the compound containing a hydrophilic part, such as polyoxypropylene, etc. can be used, for example. Polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene alkyl ether etc. are mentioned as a compound containing hydrophilic parts, such as polyoxyethylene, and a hydrophobic part mainly consisting of an alkyl group. As a compound containing hydrophilic parts, such as polyoxypropylene, the block copolymer of polyoxypropylene alkyl ether, polyoxyethylene, and polyoxypropylene, etc. are mentioned.

Examples of the ionic surfactants include cationic surfactants, anionic surfactants, zwitterionic surfactants, and the like. Examples of the cationic surfactant include cetyl trimethyl ammonium bromide and cetyl trimethyl ammonium chloride. Examples of anionic surfactants include sodium dodecyl sulfonate. Examples of the zwitterionic surfactants include amino acid surfactants, betaine surfactants, and amine oxide surfactants. As an amino acid type surfactant, acyl glutamic acid is mentioned, for example. As a betaine surfactant, lauryl dimethyl amino acetate betaine and a stearyl dimethyl amino acetate betaine are mentioned, for example. As an amine oxide type surfactant, lauryl dimethylamine oxide is mentioned, for example.

These surfactants act to suppress phase separation by reducing the difference in chemical affinity between the solvent in the reaction system and the growing siloxane polymer in the wet gel formation step described later.

Although the addition amount of surfactant depends also on the kind of surfactant, the kind, and quantity of a polysiloxane compound and a silane monomer, For example, it can be 1-100 mass parts with respect to 100 mass parts of total amounts of a polysiloxane compound group and a silane monomer group. Moreover, it is good also as 5-60 mass parts.

The thermal hydrolyzable compound generates a base catalyst by thermal hydrolysis, makes the reaction solution basic, and promotes the sol gel reaction in the wet gel formation step described later. Therefore, as this thermal hydrolyzable compound, if it is a compound which can make a reaction solution basic after hydrolysis, it will not specifically limit, Urea; Acid amides such as formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, and N, N-dimethylacetamide; Cyclic nitrogen compounds, such as hexamethylenetetramine, etc. are mentioned. Among these, in particular, urea can easily obtain the promoting effect.

The amount of the thermohydrolyzable compound to be added is not particularly limited as long as it is an amount capable of sufficiently promoting the sol gel reaction in the wet gel formation step described later. For example, when urea is used as a thermal hydrolyzable compound, the addition amount may be 1-200 mass parts with respect to 100 mass parts of total amounts of a polysiloxane compound group and a silane monomer group, and may also be 2-150 mass parts. . By setting the addition amount to 1 part by mass or more, good reactivity is more easily obtained, and by setting it to 200 parts by mass or less, it is easy to further suppress precipitation of crystals and a decrease in the gel density.

The hydrolysis of the sol formation step is also dependent on the type and amount of the polysiloxane compound, silane monomer, acid catalyst, surfactant, and the like in the mixed solution. For example, the hydrolysis may be performed for 10 minutes to 24 hours in a temperature environment of 20 to 60 ° C. You may carry out for 5 minutes-8 hours in 50-60 degreeC temperature environment. Thereby, the hydrolysable functional groups in a polysiloxane compound and a silane monomer are fully hydrolyzed, and the hydrolysis product of a polysiloxane compound and the hydrolysis product of a silane monomer can be obtained more reliably.

However, when adding a thermohydrolysable compound in a solvent, you may adjust the temperature environment of a sol formation process to the temperature which suppresses the hydrolysis of a thermohydrolysable compound and suppresses gelation of a sol. The temperature at this time may be any temperature as long as it is a temperature at which the hydrolysis of the thermal hydrolyzable compound can be suppressed. For example, when using urea as a thermal hydrolyzable compound, the temperature environment of a sol formation process can be 0-40 degreeC, and also may be 10-30 degreeC.

(Wet gel formation process)

The wet gel formation step is a step of gelling the sol obtained in the sol generation step and then aging to obtain a wet gel. In this step, a base catalyst can be used to promote gelation.

As a base catalyst, For example, alkali metal hydroxides, such as lithium hydroxide, sodium hydroxide, potassium hydroxide, cesium hydroxide; Ammonium compounds, such as ammonium hydroxide, ammonium fluoride, ammonium chloride, and ammonium bromide; Basic sodium phosphate salts such as sodium metaphosphate, sodium pyrophosphate and sodium polyphosphate; Allylamine, diallylamine, triallylamine, isopropylamine, diisopropylamine, ethylamine, diethylamine, triethylamine, 2-ethylhexylamine, 3-ethoxypropylamine, diisobutylamine, 3 -(Diethylamino) propylamine, di-2-ethylhexylamine, 3- (dibutylamino) propylamine, tetramethylethylenediamine, t-butylamine, sec-butylamine, propylamine, 3- (methylamino Aliphatic amines such as) propylamine, 3- (dimethylamino) propylamine, 3-methoxyamine, dimethylethanolamine, methyldiethanolamine, diethanolamine and triethanolamine; And nitrogen-containing heterocyclic compounds such as morpholine, N-methylmorpholine, 2-methylmorpholine, piperazine and derivatives thereof, piperidine and derivatives thereof, imidazole and derivatives thereof. Among these, ammonium hydroxide (ammonia water) has high volatility and is difficult to remain in the water-repellent powder after drying, so that it does not impair water resistance well and is excellent in terms of economy. You may use a base catalyst individually or in mixture of 2 or more types.

By using a base catalyst, dehydration condensation reaction and dealcohol condensation reaction of the hydrolysis product of the polysiloxane compound group and silane monomer group in a sol can be accelerated | stimulated, and sol gelation can be performed in a short time. In this way, a wet gel having a higher strength (rigidity) can be obtained. In particular, ammonia has high volatility and hardly remains in the water repellent powder. Thus, by using ammonia as the base catalyst, a water-repellent powder having better water resistance can be obtained.

The addition amount of a base catalyst can be 0.5-5 mass parts with respect to 100 mass parts of total amounts of a polysiloxane compound group and a silane monomer group, and may also be 1-4 mass parts. By adding the amount in an amount of 0.5 parts by mass or more, gelation can be performed in a shorter time, and by using 5 parts by mass or less, a decrease in water resistance can be further suppressed.

The gelation of the sol in the wet gel formation step may be performed in a sealed container so that the solvent and the base catalyst do not volatilize. Gelling temperature can be 30-90 degreeC, for example, and may also be 40-80 degreeC. By making gelation temperature 30 degreeC or more, gelatinization can be performed in a short time and the wet gel with higher intensity | strength (stiffness) can be obtained. Moreover, since the volatilization of a solvent (especially alcohols) becomes easy to be suppressed by making gelation temperature into 90 degrees C or less, it can gelatinize, suppressing volume shrinkage.

Aging in the wet gel formation step may be performed in a sealed container so that the solvent and the base catalyst do not volatilize. By aging, the bonding of the components constituting the wet gel is strengthened, and as a result, a wet gel having a high strength (stiffness) sufficient to suppress shrinkage during drying can be obtained. Aging temperature can be 30-90 degreeC, for example, and may also be 40-80 degreeC. By setting the aging temperature to 30 ° C. or higher, a wet gel having a higher strength (rigidity) can be obtained, and by setting the aging temperature to 90 ° C. or lower, volatilization of the solvent (especially alcohols) can be easily suppressed. It can gelatinize while suppressing.

In addition, since it is often difficult to determine the end point of gelation of the sol, gelation of the sol and subsequent maturation may be performed by a series of operations continuously.

The gelation time and the aging time differ depending on the gelation temperature and the aging temperature, but the gelation time and the aging time can be summed, for example, 4 to 480 hours, or 6 to 120 hours. By setting the sum of the gelation time and the aging time to 4 hours or more, a wet gel having a higher strength (rigidity) can be obtained, and the aging effect can be more easily maintained by setting it to 480 hours or less.

In order to reduce the density of the obtained water-repellent powder or to increase the average pore size, the gelation temperature and the aging temperature can be increased within the above range, or the total time of the gelling time and the aging time can be increased within the above range. Moreover, in order to raise the density of the water-repellent powder obtained, or to reduce an average pore diameter, gelling temperature and aging temperature can be lowered in the said range, or the total time of gelation time and aging time can be shortened in the said range.

(Wet gel grinding process)

It is a process of grinding the wet gel obtained in the wet gel formation process. Grinding of the wet gel can be performed, for example, by putting the wet gel in a Henschel mixer or by performing a wet gel production process in the mixer, and operating the mixer at an appropriate rotational speed and time. In addition, the simpler grinding of the wet gel can be performed by putting the wet gel in a sealable container, or performing a wet gel formation step in a sealable container, and shaking it for a suitable time using a shaking device such as a shaker. . In addition, you may adjust the particle diameter of a wet gel using a jet mill, a roller mill, a beads mill, etc. as needed.

(Washing and Solvent Substitution Process)

The washing and solvent replacement step includes a step of washing the wet gel obtained by the wet gel grinding step (cleaning step), and a step of replacing the cleaning liquid in the wet gel with a solvent suitable for drying conditions (dry step described later) (solvent substitution). Process). The washing and solvent replacement step may be carried out in a form in which only the solvent replacement step is performed without performing the step of washing the wet gel. However, impurities such as unreacted substances and by-products in the wet gel are reduced to obtain a higher purity water repellent powder. In view of enabling the preparation of the wet gel, the wet gel may be washed.

In the washing step, the wet gel obtained in the wet gel forming step is washed. The said washing | cleaning can be performed repeatedly using water or an organic solvent, for example. At this time, heating efficiency can be improved by heating.

As the organic solvent, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, acetone, methyl ethyl ketone, 1,2-dimethoxyethane, acetonitrile, hexane, toluene, diethyl ether, chloroform, ethyl acetate And various organic solvents such as tetrahydrofuran, methylene chloride, N, N-dimethylformamide, dimethyl sulfoxide, acetic acid and formic acid can be used. You may use an organic solvent individually or in mixture of 2 or more types.

In the solvent substitution process mentioned later, in order to suppress shrinkage of the gel by drying, the solvent of low surface tension can be used. However, solvents with low surface tension generally have very low mutual solubility with water. Therefore, in the case of using a solvent having a low surface tension in the solvent substitution step, a hydrophilic organic solvent having high mutual solubility with respect to both water and a solvent having a low surface tension may be used as the organic solvent used in the washing step. . In addition, the hydrophilic organic solvent used in the washing process may serve as a preliminary substitution for the solvent substitution process. Among the above organic solvents, examples of the hydrophilic organic solvent include methanol, ethanol, 2-propanol, acetone and methyl ethyl ketone. In addition, methanol, ethanol, methyl ethyl ketone and the like are excellent in terms of economy.

As the amount of water or organic solvent used in the washing step, the solvent in the wet gel can be sufficiently substituted to be an amount capable of washing. The amount can be 3 to 10 times the amount of the wet gel. Washing can be repeated until the moisture content in the wet gel after washing | cleaning becomes 10 mass% or less with respect to a mass of silica.

The temperature environment in a washing | cleaning process can be made into the temperature below the boiling point of the solvent used for washing | cleaning, For example, when using methanol, it can be made into the heating of about 30-60 degreeC.

In the solvent substitution process, in order to suppress shrinkage in the drying process mentioned later, the solvent of the wash | cleaned wet gel is substituted by the predetermined solvent for substitution. At this time, the heating efficiency can be improved by heating. Specifically as a solvent for substitution, when drying at atmospheric pressure at the temperature below the critical point of the solvent used for drying in a drying process, the solvent of the low surface tension mentioned later is mentioned. On the other hand, in the case of supercritical drying, examples of the solvent for substitution include ethanol, methanol, 2-propanol, dichlorodifluoromethane, carbon dioxide, or a solvent in which two or more thereof are mixed. .

As a solvent of low surface tension, the solvent whose surface tension in 20 degreeC is 30 mN / m or less is mentioned. The surface tension may be 25 mN / m or less or 20 mN / m or less. As solvents of low surface tension, for example, pentane (15.5), hexane (18.4), heptane (20.2), octane (21.7), 2-methylpentane (17.4), 3-methylpentane (18.1), 2- Aliphatic hydrocarbons such as methyl hexane (19.3), cyclopentane (22.6), cyclohexane (25.2), and 1-pentene (16.0); Aromatic hydrocarbons such as benzene (28.9), toluene (28.5), m-xylene (28.7) and p-xylene (28.3); Halogenated hydrocarbons such as dichloromethane (27.9), chloroform (27.2), carbon tetrachloride (26.9), 1-chloropropane (21.8), and 2-chloropropane (18.1); Ethers such as ethyl ether (17.1), propyl ether (20.5), isopropyl ether (17.7), butyl ethyl ether (20.8), and 1,2-dimethoxyethane (24.6); Ketones such as acetone (23.3), methyl ethyl ketone (24.6), methyl propyl ketone (25.1), and diethyl ketone (25.3); Ester, such as methyl acetate (24.8), ethyl acetate (23.8), propyl acetate (24.3), isopropyl acetate (21.2), isobutyl acetate (23.7), and ethyl butyrate (24.6), is mentioned (20 in parentheses). Surface tension in ° C, and the unit is [mN / m]. Among these, aliphatic hydrocarbons (hexane, heptane, etc.) have low surface tension and are excellent in working environment. Moreover, among these, it can use also as the organic solvent of the said washing process by using hydrophilic organic solvents, such as acetone, methyl ethyl ketone, and 1, 2- dimethoxyethane. Moreover, among these, since the drying in the drying process mentioned later is easy, you may use the solvent whose boiling point at normal pressure is 100 degrees C or less. You may use said organic solvent individually or in mixture of 2 or more types.

The amount of the solvent used in the solvent replacement step may be an amount capable of sufficiently replacing the solvent in the wet gel after washing. The amount can be 3 to 10 times the amount of the wet gel.

The temperature environment in a solvent substitution process can be made into the temperature below the boiling point of the solvent used for substitution, and when heptane is used, it can be made into about 30-60 degreeC heating.

(Drying process)

In the drying step, the pulverized product of the wet gel washed and solvent-substituted as described above is dried. Thereby, water repellent powder can be finally obtained.

There is no restriction | limiting in particular as a drying method, Although well-known normal pressure drying, supercritical drying, or lyophilization can be used, from this viewpoint, it is easy to manufacture a low density water repellent powder, and normal pressure drying or supercritical drying can be used. . Moreover, atmospheric pressure drying can be used from a viewpoint that it can produce at low cost. In addition, in this embodiment, normal pressure means 0.1 Mpa (atmospheric pressure).

The water-repellent powder of this embodiment can be obtained by drying under washing | cleaning and solvent-substituted wet gel, and drying at atmospheric pressure at the temperature below the critical point of the solvent used. The drying temperature is different depending on the type of the substituted solvent, and in particular, drying at a high temperature may increase the evaporation rate of the solvent, and may be 20 to 80 ° C in consideration of the fact that a large crack may occur in the gel. . In addition, the said drying temperature may be 30-60 degreeC further. Moreover, although drying time changes with the capacity of a wet gel and drying temperature, it can be 4 to 120 hours. In addition, in this embodiment, it is also included in normal pressure drying to apply pressure and to dry quickly within the range which does not impair productivity.

The water-repellent powder of this embodiment can also be obtained by supercritical drying the wet gel which wash | cleaned and solvent-substituted. Supercritical drying can be performed by a well-known method. As a method of supercritical drying, the method of removing a solvent by the temperature and pressure more than the critical point of the solvent contained in a wet gel, for example is mentioned. Or as a method of supercritical drying, wet gel is immersed in liquefied carbon dioxide on 20-25 degreeC, about 5-20 MPa conditions, for example, all or part of the solvent contained in a wet gel is covered. After substituting with carbon dioxide having a lower critical point than the solvent, a method of removing carbon dioxide alone or a mixture of carbon dioxide and a solvent may be mentioned.

The water-repellent powder obtained by such atmospheric pressure drying or supercritical drying may be further dried at 105 to 200 ° C. for about 0.5 to 2 hours under normal pressure. This makes it easy to obtain a water-repellent powder having a low density and small pores. Further drying can be performed at 150-200 degreeC under normal pressure.

[Average particle diameter]

Although the average particle diameter D50 of the water repellent powder of this embodiment can be 1-1000 micrometers, 3-700 micrometers may be sufficient and 5-500 micrometers may be sufficient. When the average particle diameter D50 of a water repellent powder is 1 micrometer or more, the formation property and adhesiveness of the water repellent film with respect to an object become easy to be improved. In addition, the average particle diameter of a water repellent powder can be suitably adjusted with methods, such as a grinding | pulverization method, grinding | pulverization conditions, a sieve, and classification.

The average particle diameter D50 of the water repellent powder can be measured by a laser diffraction scattering method. For example, the powder is dispersed by adding a water-repellent powder to a solvent (methanol) within the range of 0.05-5 mass% of concentration, and vibrating for 15 to 30 minutes with a 50 W ultrasonic homogenizer. Thereafter, about 10 ml of the dispersion is injected into a laser diffraction scattering particle size distribution analyzer, and the particle size is measured at 25 ° C. with a refractive index of 1.3 and an absorption of 0. And the particle diameter in 50% of the integrated value (volume basis) in this particle diameter distribution is made into average particle diameter D50. As a measuring apparatus, Microtrac MT3000 (made by Nikkiso Corporation, product name) can be used, for example.

[Compression modulus]

The compressive elastic modulus at 25 degrees C of the water repellent powder of this embodiment can be 2.0 Mpa or less, 1.5 Mpa or less, 1.3 Mpa or less, or 1.0 Mpa or less. When the compressive elastic modulus is 2 MPa or less, sufficient adhesiveness can be ensured when the water-repellent powder is fixed to the workpiece. In addition, although the lower limit of a compressive elastic modulus is not specifically limited, For example, it can be 0.05 Mpa. The compressive elastic modulus can be measured using a micro compression tester "MCT-510" (manufactured by Shimadzu Corporation, product name).

<Water repellent treatment method using water repellent powder>

Next, the water repellent treatment method using the water repellent powder of the present embodiment will be described. The water repellent treatment method using the water repellent powder is not particularly limited, and for example, the object can be subjected to a water repellent treatment by the following method.

In the water repellent treatment, the water repellent powder may be directly contacted with the target surface of the object, or the water repellent treatment liquid containing the water repellent powder may be contacted with the target surface of the object. Since the water repellent powder of this embodiment has flexibility, a water repellent powder can be arrange | positioned to the to-be-processed surface of a target object, and a water-repellent part can be formed in a to-be-processed surface.

You may perform the water repellent treatment of the object using the water repellent powder of this embodiment by the method of making water repellent powder directly contact the to-be-processed surface of a target object, for example. Specifically, after the water repellent powder is disposed on the surface to be treated, it is rubbed well (coated), and the excess water repellent powder is sieved to drop, whereby the surface to be treated can be subjected to a water repellent treatment (forming a water repellent).

The water-repellent treatment of the object using the water-repellent treatment liquid containing the water-repellent powder of this embodiment may be performed by the method mainly equipped with the manufacturing process of a water-repellent treatment liquid, an application | coating process, and a drying process. Hereinafter, each process of the water repellent treatment method using the water repellent treatment liquid which concerns on this embodiment is demonstrated.

(Manufacturing Process of Water Repellent Treatment Liquid)

The water repellent treatment liquid according to the present embodiment can be produced by dispersing the water repellent powder in an organic solvent. By using the said water repellent treatment liquid, a water repellent part can be formed uniformly on the to-be-processed surface of the target object. The water repellent part may be an embodiment (water repellent film) having a film-like appearance in which fine water repellent powder is deposited at a predetermined thickness, or may be an embodiment (water repellent particles) having a particulate appearance in which coarse water repellent powder adheres to a plane.

Examples of the organic solvent include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, acetone, methyl ethyl ketone, 1,2-dimethoxyethane, acetonitrile, heptane, hexane, toluene, diethyl ether, chloroform, Various organic solvents, such as ethyl acetate, tetrahydrofuran, methylene chloride, N, N- dimethylformamide, dimethyl sulfoxide, acetic acid, formic acid, can be used. You may use an organic solvent individually or in mixture of 2 or more types.

(Application process)

An application | coating process is a process of apply | coating a water repellent liquid to a to-be-processed surface. Moreover, depending on the case, you may dry a to-be-processed surface after application | coating and volatilize a solvent. By this process, a water repellent part can be formed in a to-be-processed surface. The water repellent treatment liquid may be applied to the entire surface to be treated or may be selectively applied to a portion of the surface to be treated.

Although it does not specifically limit as a coating method, For example, a spin coat method, the dip coat method, the spray coat method, the flow coat method, the bar coat method, and the gravure coat method are mentioned. In particular, the spray coating method is preferable because the water-repellent part can be formed on the surface to be treated with irregularities with a uniform thickness, and the productivity is high and the use efficiency of the water-repellent powder is good. The coating method may be used alone or in combination of two or more.

You may form a water repellent part on a to-be-processed surface by apply | coating or impregnating a water repellent liquid to another base material (film, cloth, etc.), and then making contact with a to-be-processed surface. The coating method can be freely selected depending on the amount of water repellent treatment liquid used, the area of the surface to be treated, the characteristics, and the like.

Although the material which comprises a to-be-processed surface is not specifically limited, For example, metal, ceramics, glass, a plastic, and the material (composite material, laminated material, etc.) which combined these are mentioned. The water repellent treatment liquid can also be applied to paper, fiber, cloth, nonwoven fabric, rubber, leather and the like. When the surface to be treated is dried and the solvent is volatilized after applying the water repellent treatment liquid, the material constituting the surface to be treated may be a water-soluble organic compound, a water-soluble inorganic compound, or the like. Among these, it is preferable that the material which comprises a to-be-processed surface is a transparent material, such as glass and a plastic.

As a metal, stainless steel, aluminum, copper, a galvanized steel plate, and iron are mentioned, for example. Examples of the ceramics include alumina, barium titanate, boron nitride, and silicon nitride. As glass, a normal soda-lime glass, borosilicate glass, an alkali free glass, quartz glass, an aluminosilicate glass, etc. are mentioned, for example. Examples of the plastic include acrylic resins such as polymethyl methacrylate, aromatic polycarbonate resins such as polyphenylene carbonate, and aromatic polyester resins such as polyethylene terephthalate (PET).

As a water-soluble organic compound, glucose, sucrose, starch, polyacrylamide, polyvinyl alcohol, methyl cellulose, etc. are mentioned, for example. As a water-soluble inorganic compound, water glass, sodium chloride, sodium phosphate, sodium carbonate, sodium vanadate, sodium borate, potassium chloride, potassium carbonate, and a sulfuric acid compound are mentioned, for example.

After apply | coating a water repellent liquid, the to-be-processed surface is dried and a solvent is volatilized, and the adhesiveness of a water repellent part can further be improved. The drying temperature at this time is not particularly limited and may vary depending on the heat resistance temperature of the surface to be treated, and may be, for example, 60 to 250 ° C or 120 to 180 ° C. By making the said temperature 60 degreeC or more, more excellent adhesiveness can be achieved, and by setting it as 250 degrees C or less, deterioration by heat can be suppressed.

(Drying process)

A drying process is a process of drying the to-be-processed surface in which the water repellent part was formed.

Although it does not restrict | limit especially as a drying method, For example, a well-known drying method under atmospheric pressure can be used. The drying temperature is different depending on the heat resistance temperature and the like of the surface to be treated. From a viewpoint that solvent evaporation rate is fast enough and it is easy to prevent deterioration of a water repellent part, 20-250 degreeC may be sufficient as a drying temperature, for example, 60-180 degreeC may be sufficient as it. Although drying time changes with mass of a water repellent part, and drying temperature, it may be 1 to 24 hours, for example.

The thickness of a water repellent part is not specifically limited, It can adjust suitably by the magnitude | size of a water repellent powder, the formation method of a water repellent part, etc. When the object is treated using a water repellent treatment liquid containing a water repellent powder, the thickness of the water repellent part formed can be, for example, 1 to 1000 µm which is the particle size of the water repellent powder. On the other hand, when using the method (application method etc.) which makes water-repellent powder directly contact the to-be-processed surface, the water-repellent powder is crushed to some extent, and the thickness of a water-repellent part can be 1-500 nm, for example.

It is preferable that the adhesion amount of the water repellent powder in a to-be-processed surface is one or more per 1 mm square. By setting it as 1 or more, more excellent water repellency can be achieved. In addition, the adhesion amount of water repellent powder can be computed using a scanning electron microscope (SEM). For example, in the case of a water-repellent powder having an average particle diameter of 100 nm, a square area A (1.0 × 10 ⁻⁴ mm ² ) having a length (1.0 × 10 ⁻² mm) of 100 times the average particle diameter as one side is set. The number B of particles in the square is measured to calculate B / A. This is repeated 10 times and the average value of the obtained B / A is defined as the adhesion amount of particles.

The water repellent part formed on the surface to be treated by the water repellent powder can be an aerogel in that more excellent water repellency can be achieved. The airgel formed here is a porous body having micropores of nanometer size. It is thought that an airgel shows the outstanding water repellency in the point where there are few hydroxyl groups on the surface, and water is hard to enter into micropores. Moreover, since an airgel has a large porosity, it is thought that the refractive index of the water-repellent part which is an airgel is small, and a water-repellent part with high transparency can be obtained.

By the above-mentioned water repellent treatment method using the water repellent powder of this embodiment, the water repellent part which has the outstanding water repellency and flexibility can be formed in a to-be-processed surface. The water repellent structure in which such a water repellent part is formed can express excellent water repellency and durability.

EXAMPLE

Next, the present invention will be described in more detail with reference to the following examples, but these examples do not limit the present invention in any sense.

(Example 1)

[Production of Water-Repellent Powder 1]

As a polysiloxane compound, 40.0 parts by mass of carbinol-modified siloxane "X-22-160AS" (manufactured by Shin-Etsu Chemical Co., Ltd., product name) is used as a methyltrimethoxysilane "LS-530" (manufactured by Shin-Etsu Chemical Co., Ltd.) Product name: Hereafter, abbreviated as "MTMS", 60.0 parts by mass, 120.0 parts by mass of water and 80.0 parts by mass of methanol were mixed, 0.10 parts by mass of acetic acid was added thereto as an acid catalyst, and reacted at 25 ° C. for 8 hours. Got it. 40.0 mass parts of ammonia water of 5% concentration was added to the obtained sol as a base catalyst, and gelatinized at 60 degreeC for 8 hours, and it aged at 80 degreeC for 48 hours, and obtained the wet gel 1.

The wet gel 1 was transferred to a plastic bottle, and after being sealed, it was ground for 10 minutes at 27000 rpm using an extreme mill (MX-1000XTS manufactured by Azwan Co., Ltd.) to obtain a particulate wet gel 1. The obtained particulate wet gel 1 was immersed in 2500 parts by mass of methanol, and washed at 60 ° C. over 12 hours. This washing operation was performed three times in total while exchanging with fresh methanol. Next, the wash | cleaned particulate wet gel was immersed in 2500 mass parts of heptanes which are low surface tension solvents, and solvent substitution was performed at 40 degreeC over 12 hours. This solvent substitution operation was performed three times in total, exchanging with fresh heptane. The washed and solvent-substituted particulate wet gel was dried at 40 ° C. for 96 hours at atmospheric pressure, and further dried at 150 ° C. for 2 hours. The dried gel was sieved through a sieve (manufactured by Tokyo Screen Co., Ltd., 45 µm in diameter and 32 µm in diameter) to obtain a water repellent powder 1 having a structure represented by the general formula (1).

[Production of Water-repellent Treatment Liquid 1]

To 500.0 g of methyl ethyl ketone (MEK), 5.0 g of the water-repellent powder 1 was dispersed to obtain a water-repellent treatment liquid 1.

[Water repellent structure 1]

After dipping slide glass S7213 (Matsunami Glass Industry Co., Ltd. product name) to water repellent liquid 1 for 5 minutes, the dip processed slide glass was dried at 120 degreeC under normal pressure for 1 hour, and the water repellent structure 1 was obtained.

(Example 2)

[Production of Water-Repellent Powder 2]

200.0 parts by mass of water, 0.10 parts by mass of acetic acid, 20.0 parts by mass of CTAB and 120.0 parts by mass of urea were added thereto, and 40.0 parts by mass of polysiloxane compound A and 60.0 parts by mass of MTMS were added thereto, followed by reaction at 25 ° C. for 2 hours. To give a sol. The obtained sol gelled at 60 ° C. for 8 hours, and then aged at 80 ° C. for 48 hours to obtain a wet gel. Thereafter, in the same manner as in Example 1, a water-repellent powder 2 having a ladder structure including the structures represented by the general formulas (2) and (3) was obtained.

In addition, said "polysiloxane compound A" was synthesize | combined as follows. First, in a 1 liter three-necked flask equipped with a stirrer, a thermometer, and a Jimlot cooling tube, 100.0 parts by mass of hydroxy-terminated dimethylpolysiloxane "XC96-723" (manufactured by Momentive, Inc., product name) and methyltrimethoxysilane were added. 181.3 mass part and 0.50 mass part of t-butylamines were mixed, and it reacted at 30 degreeC for 5 hours. Then, this reaction liquid was heated at 140 degreeC under pressure reduction of 1.3 kPa for 2 hours, and the volatile matter was removed, and both terminal bifunctional alkoxy modified polysiloxane compound (polysiloxane compound A) was obtained.

[Production of Water-repellent Treatment Liquid 2]

With respect to MEK 500.0 g, 5.0 g of the water-repellent powder 2 was dispersed to obtain a water-repellent treatment liquid 2.

[Water repellent structure 2]

After dipping slide glass S7213 into water repellent liquid 2 for 5 minutes, the dip processed slide glass was dried at 120 degreeC under normal pressure for 1 hour, and the water repellent structure 2 was obtained.

(Example 3)

[Production of Water-Repellent Powder 3]

200.0 parts by mass of water, 0.10 parts by mass of acetic acid, 20.0 parts by mass of CTAB, and 120.0 parts by mass of urea, and 20.0 parts by mass of X-22-160AS, 60.0 parts by mass of MTMS and bistrimethoxysilylhexane 20.0 mass parts was added and reacted at 25 degreeC for 2 hours, and the sol was obtained. The obtained sol gelled at 60 ° C. for 8 hours, and then aged at 80 ° C. for 48 hours to obtain a wet gel. After that, in the same manner as in Example 1, water-repellent powder 3 having a structure represented by the general formula (1) was obtained.

[Production of Water-repellent Treatment Liquid 3]

About 500.0 g of MEK, 5.0 g of said water-repellent powder 3 was disperse | distributed and the water repellent liquid 3 was obtained.

[Water repellent structure 3]

After dipping slide glass S7213 into water-repellent liquid 3 for 5 minutes, the dip-treated slide glass was dried at 120 degreeC for 1 hour under normal pressure, and the water-repellent structure 3 was obtained.

(Example 4)

[Production of Water Repellent Powder 4]

200.0 parts by mass of water, 0.10 parts by mass of acetic acid, 20.0 parts by mass of CTAB and 120.0 parts by mass of urea were added thereto, 20.0 parts by mass of polysiloxane compound A, 60.0 parts by mass of MTMS and 20.0 of bistrimethoxysilylhexane. A mass part was added and reacted at 25 degreeC for 2 hours, and the sol was obtained. The obtained sol gelled at 60 ° C. for 8 hours, and then aged at 80 ° C. for 48 hours to obtain a wet gel. Then, it carried out similarly to Example 1, and obtained the water repellent powder 4 which has the ladder structure shown by the said General formula (2) and (3).

[Production of Water-repellent Treatment Liquid 4]

About 500.0 g of MEK, 5.0 g of said water-repellent powder 4 was disperse | distributed and the water repellent liquid 4 was obtained.

[Water repellent structure 4]

After dipping slide glass S7213 into water-repellent liquid 4 for 5 minutes, the dip-treated slide glass was dried at 120 degreeC for 1 hour under normal pressure, and the water-repellent structure 4 was obtained.

(Example 5)

[Production of Water-Repellent Powder 5]

200.0 parts by mass of water, 0.10 parts by mass of acetic acid, 20.0 parts by mass of CTAB and 120.0 parts by mass of urea were added thereto, 20.0 parts by mass of X-22-160AS, 20.0 parts by mass of polysiloxane compound A and 60.0 parts by mass of MTMS. It added and reacted at 25 degreeC for 2 hours, and obtained the sol. The obtained sol gelled at 60 ° C. for 8 hours, and then aged at 80 ° C. for 48 hours to obtain a wet gel. Thereafter, in the same manner as in Example 1, a water-repellent powder 5 having a structure represented by the general formula (1) and a ladder type structure represented by the general formulas (2) and (3) was obtained.

[Production of Water-repellent Treatment Liquid 5]

About 500.0 g of MEK, 5.0 g of said water-repellent powder 5 was disperse | distributed and the water repellent liquid 5 was obtained.

[Water repellent structure 5]

After dipping slide glass S7213 into water repellent liquid 5 for 5 minutes, the dip processed slide glass was dried at 120 degreeC for 1 hour under normal pressure, and the water repellent structure 5 was obtained.

(Example 6)

[Production of Water Repellent Powder 6]

200.0 parts by mass of water, 0.10 parts by mass of acetic acid, 20.0 parts by mass of CTAB and 120.0 parts by mass of urea were mixed, and dimethyldimethoxysilane KBM-22 (manufactured by Shin-Etsu Chemical Co., Ltd., product name: `` DMDMS '' below) 20.0 mass parts), 20.0 mass parts of polysiloxane compound A, and 60.0 mass parts of MTMS were added, and it reacted at 25 degreeC for 2 hours, and the sol was obtained. The obtained sol gelled at 60 ° C. for 8 hours, and then aged at 80 ° C. for 48 hours to obtain a wet gel. Then, it carried out similarly to Example 1, and obtained the water repellent powder 6 which has the ladder structure shown by the said General formula (2) and (3).

[Production of Water-repellent Treatment Liquid 6]

About 500.0 g of MEK, 5.0 g of said water-repellent powders 6 were disperse | distributed and the water-repellent treatment liquid 6 was obtained.

[Water repellent structure 6]

Slide glass S7213 was dip | poured in water repellent liquid 6 for 5 minutes. Then, the dip glass slide glass was dried at 120 degreeC for 1 hour under normal pressure, and the water repellent structure 6 was obtained.

(Example 7)

[Production of Water Repellent Powder 7]

200.0 parts by mass of water, 0.10 parts by mass of acetic acid, 20.0 parts by mass of CTAB and 120.0 parts by mass of urea were added thereto, and 40.0 parts by mass of polysiloxane compound B and 60.0 parts by mass of MTMS were added thereto, followed by reaction at 25 ° C. for 2 hours. To give a sol. The obtained sol gelled at 60 ° C. for 8 hours, and then aged at 80 ° C. for 48 hours to obtain a wet gel. After that, in the same manner as in Example 1, water-repellent powder 7 having a ladder structure shown in the general formulas (2) and (3) was obtained.

In addition, said "polysiloxane compound B" was synthesize | combined as follows. First, in a 1 liter three-necked flask equipped with a stirrer, a thermometer, and a luggage lot cooling tube, 100.0 parts by mass of XC96-723, 202.6 parts by mass of tetramethoxysilane and 0.50 parts by mass of t-butylamine were mixed. It was made to react at 5 degreeC for 5 hours. Then, this reaction liquid was heated at 140 degreeC under pressure reduction of 1.3 Pa for 2 hours, and volatile matter was removed, and both terminal trifunctional alkoxy modified polysiloxane compound (polysiloxane compound B) was obtained.

[Production of Water-repellent Treatment Liquid 7]

About 500.0 g of MEK, 5.0 g of said water-repellent powder 7 was disperse | distributed and the water repellent liquid 7 was obtained.

[Water repellent structure 7]

After dipping the slide glass S7213 into water repellent liquid 7 for 5 minutes, the dip processed slide glass was dried at 120 degreeC under normal pressure for 1 hour, and the water repellent structure 7 was obtained.

(Example 8)

[Production of Water-Repellent Powder 8]

100.0 parts by mass of water, 100.0 parts by mass of PL-2L (manufactured by Fuso Chemical Co., Ltd., spherical colloidal silica, average primary particle diameter: 20 nm), 20.0 parts by mass of CTAB and 120.0 parts by mass of urea, 20.0 mass parts of polysiloxane compound A, 20.0 mass part of DMDMS, and 60.0 mass part of MTMS were added, and it reacted at 25 degreeC for 2 hours, and the sol was obtained. The obtained sol gelled at 60 ° C. for 8 hours, and then aged at 80 ° C. for 48 hours to obtain a wet gel. Then, it carried out similarly to Example 1, and obtained the water repellent powder 8 which has the ladder structure shown by the said General formula (2) and (3).

[Production of Water-repellent Treatment Liquid 8]

About 500.0 g of MEK, 5.0g of said water-repellent powders 8 were disperse | distributed and the water-repellent treatment liquid 8 was obtained.

[Water repellent structure 8]

After dipping slide glass S7213 into water repellent liquid 8 for 5 minutes, the dip processed slide glass was dried at 120 degreeC for 1 hour under normal pressure, and the water repellent structure 8 was obtained.

(Example 9)

[Production of Water-Repellent Powder 9]

100.0 parts by mass of water, 100.0 parts by mass of PL-5L (Fuso Chemical Co., Ltd., cocoon-type colloidal silica, average primary particle size: 50 nm), 20.0 parts by mass of CTAB, and 120.0 parts by mass of urea, 20.0 mass parts of polysiloxane compound A, 20.0 mass part of DMDMS, and 60.0 mass part of MTMS were added to this, and it reacted at 25 degreeC for 2 hours, and the sol was obtained. The obtained sol gelled at 60 ° C. for 8 hours, and then aged at 80 ° C. for 48 hours to obtain a wet gel. Then, it carried out similarly to Example 1, and obtained the water repellent powder 9 which has the ladder structure shown by the said General formula (2) and (3).

[Production of Water-repellent Treatment Liquid 9]

About 500.0 g of MEK, 5.0 g of said water-repellent powders 9 were disperse | distributed and the water-repellent treatment liquid 9 was obtained.

Water repellent structure 9

After dipping the slide glass S7213 into water repellent liquid 9 for 5 minutes, the dip processed slide glass was dried at 120 degreeC for 1 hour under normal pressure, and the water repellent structure 9 was obtained.

(Example 10)

After arranging 1.0 g of water repellent powder 1 on the slide glass S7213, the surface of the slide glass was rubbed a plurality of times with the KIMEA TOKYO product made from Kuresia Co., Ltd. from the water repellent powder 1 place, and the excess water repellent powder 1 was sieved and dropped to repel the water repellent structure. 10 was obtained (In addition, in Table 2, this water repellent treatment method was described as a "drawing method".).

(Example 11)

Except having used the water repellent powder 2, it processed similarly to Example 10, and obtained the water repellent structure 11.

(Example 12)

Except having used the water repellent powder 3, it processed similarly to Example 10, and obtained the water repellent structure 12.

(Example 13)

Except having used the water repellent powder 6, it processed similarly to Example 10, and obtained the water repellent structure 13.

(Example 14)

Except having used the water repellent powder 8, it processed similarly to Example 10, and obtained the water repellent structure 14.

(Comparative Example 1)

[Production of Comparative Water-repellent Powder 1]

200.0 mass parts of water, 0.10 mass part of acetic acid, 20.0 mass parts of CTAB, and 120.0 mass parts of urea were mixed, 100.0 mass parts of MTMS was added to this, and it reacted at 25 degreeC for 2 hours, and the sol was obtained. The obtained sol gelled at 60 ° C. for 8 hours, and then aged at 80 ° C. for 48 hours to obtain a wet gel. Thereafter, a comparative water repellent powder 1 was obtained in the same manner as in Example 1.

[Production of Comparative Water-repellent Treatment Liquid 1]

About 500.0 g of MEK, 5.0 g of comparative water-repellent powders 1 were disperse | distributed and the comparative water-repellent treatment liquid 1 was obtained.

[Comparative Water Repellent Structure 1]

After dipping slide glass S7213 in the comparative water-repellent treatment liquid 5 minutes for 5 minutes, the dip-treated slide glass was dried at 120 degreeC under normal pressure for 1 hour, and the comparative water-repellent structure 1 was obtained.

(Comparative Example 2)

[Production of Comparative Water-repellent Powder 2]

200.0 parts by mass of water, 0.10 parts by mass of acetic acid, 20.0 parts by mass of CTAB, and 120.0 parts by mass of urea were added thereto, and 100.0 parts by mass of tetraethoxysilane (TEOS) was added thereto, and the mixture was reacted at 25 ° C for 2 hours for sol. Got. The obtained sol gelled at 60 ° C. for 8 hours, and then aged at 80 ° C. for 48 hours to obtain a wet gel. Thereafter, a comparative water repellent powder 2 was obtained in the same manner as in Example 1.

[Production of Comparative Water-repellent Treatment Liquid 2]

About 500.0 g of MEK, 5.0 g of comparative water-repellent powders 2 were disperse | distributed and the comparative water-repellent treatment liquid 2 was obtained.

[Comparative Water Repellent Structure 2]

After sliding slide glass S7213 for 5 minutes to comparative water-repellent liquid 2, the dip-treated slide glass was dried at 120 degreeC under normal pressure for 1 hour, and the comparative water-repellent structure 2 was obtained.

(Comparative Example 3)

Except having used the comparative water repellent powder 1, it processed like Example 10 and the comparative water repellent structure 3 was obtained.

(Comparative Example 4)

Except having used the comparative water repellent powder 2, it processed like Example 10 and the comparative water repellent structure 4 was obtained.

Table 1 shows Si raw materials (polysiloxane compounds, silane monomers, silica particles) and compounding amounts in the examples and the comparative examples.

[Various evaluation]

About the water repellent powder obtained by each Example and the comparative example, it evaluated in accordance with the following conditions. The evaluation results are shown in Table 1 or Table 2.

(1) FT-IR peak intensity measurement

The infrared absorption spectrum of the water-repellent powder was measured using "FT-IR / 6300" (made by Nihon spectroscopy) as a Fourier transform infrared spectrometer. The measurement was performed by measuring the base line with air and then attaching the measurement sample (0.01 g of water repellent powder) to the prism portion of the ATR unit. As for measurement conditions, ATR, the measurement wave number range was 400-4000 cm <^-1> , and the integration count was 128 circuits for the measurement mode. In the obtained spectral data, when the peak intensity of wave number 1070 cm ^-1 was defined as 1.0, the peak intensity of 1270 cm ^-1 was calculated.

For example, FIG. 3: is a figure which shows the infrared absorption spectrum of water repellent powder 2, water repellent powder 6, comparative water repellent powder 1, and comparative water repellent powder 2. FIG. 3, it can confirm that the peak intensity of 1270 cm <^-1> concerning water-repellent powder 2 and 6 exists in the range of 0.2-0.7. On the other hand, it can be confirmed that the peak intensity of comparative water repellent powder 1 is not in the above range. In addition, it can be confirmed that the comparative water repellent powder 2 does not have a peak at the position of 1270 cm ^-1 . About the comparative water repellent powder 2, the intensity | strength in the position of 1270 cm <^-1> was computed.

(2) Measurement of signal area ratios related to silicon-bonded units Q, T and D

As a solid ²⁹ Si-NMR apparatus, measurement was performed using "FT-NMR AV400WB" (manufactured by Brooke Biospin Co., Ltd., product name). Measurement conditions were made into measurement mode: DD / MAS method, probe: CPMAS probe of 4 mm diameter, magnetic field: 9.4 T, resonance frequency: 79 Hz, MAS rotation speed: 6 Hz, delay time: 150 second. As a standard sample, 3-trimethylsilylpropionate was used.

The measurement was performed by filling a ZrO ₂ rotor with water repellent powder and attaching it to a probe. In the spectral analysis, the line broadening coefficient was 2 Hz, and the signal area ratios (Q + T: D) related to the silicon-containing bonding units Q, T, and D obtained were obtained.

(3) compressive modulus

As the measuring device, a micro compression tester "MCT-510" (manufactured by Shimadzu Corporation, product name) was used. The water-repellent powder was set between the upper and lower pressure plates arranged in parallel, and compression was performed at a load rate of 0.0892 mN / sec. Measurement was complete | finished when the load of 4.9 mN second was applied or the measurement sample was destroyed. The compressive elastic modulus was calculated as follows from the compressive strain and the compressive stress.

Here, the compressive strain ε can be obtained from the following equation. In the formula, Δd represents the displacement (mm) of the thickness of the measurement sample by the load, and d1 represents the thickness (mm) of the measurement sample before applying the load.

ε = Δd / d1

In addition, compressive stress (sigma) (MPa) can be calculated | required from following Formula. In the formula, F represents a compressive force (N), and A represents the cross-sectional area (mm 2) of the measurement sample before applying the load.

σ = F / A

Compressive modulus E (MPa) can be calculated | required from following Formula, for example in the range of 0.1-0.2N of compressive force. In the formula, sigma ₁ represents a compressive stress (MPa) measured at a compressive force of 0.1 N, sigma ₂ represents a compressive stress (MPa) measured at a compressive force of 0.2 N, and ε ₁ represents a compressive stress at σ ₁ . The compressive strain measured is shown, and (epsilon) ₂ represents the compressive strain measured in compressive stress (sigma) ₂ .

E = (σ ₂ -σ ₁ ) / (ε ₂ -ε ₁ )

(4) measurement of contact angle

The water-repellent structure obtained by each Example and the comparative example was dried at 105 degreeC for 1 hour, and it was set as the measurement sample. Next, 2 microliters of ultrapure water droplets were dripped using the contact angle meter DMs-401 by Kyowa Interface Science, Inc., and the contact angle after 5 second was measured. The measurement was performed 5 times and the average value was made into the water contact angle.

(5) wear resistance test

In the abrasion resistance test, the Kuresia Co., Ltd. kimme towel was rubbed a plurality of times on the surface of the water repellent structure, and then dried at 105 ° C for 1 hour to obtain a measurement sample. The contact area of the kimme towel here was 20 mm x 50 mm, and weighted 0.1 kg / cm <2>. Next, 2 microliters of ultrapure water droplets were dripped using Kyowa Interface Science, Ltd. contact angle measuring device DMs-401, and the contact angle after 5 second was measured at room temperature. The measurement was performed 5 times and the average value was made into the water contact angle.

From Table 2, it can be confirmed that the water repellent structure having the water repellent part formed of the water repellent powder of the example has a large water contact angle, exhibits good water repellency, and has excellent flexibility as compared with the water repellent structure of the comparative example. In addition, as is apparent from the results of the wear resistance test, the water repellent structure of the example is superior in durability to the water repellent structure of the comparative example and can maintain good water repellency.

L: circumscribed rectangle,
P: silica particles.

Claims (6)

In the infrared absorption spectrum measured using Fourier transform infrared spectroscopy, when the peak intensity of the wave number 1070 cm ^-1 derived from the network structure of the Si-O-Si bond is defined as 1.0, it is derived from the Si-CH ₃ structure. Water-repellent powder whose peak intensity in the wavenumber of 1270 cm <^-1> is 0.2-0.7. Solid ²⁹ Si-NMR measured using DD / MAS method In the spectrum, when silicon-bonding units Q, T, and D are defined as follows, the ratio Q + T: D of the signal area derived from Q and T and the signal area derived from D is from 1: 0.01 to 1 : 0.50 phosphorus, water repellent powder.
Q: A silicon-bonded unit having four oxygen atoms bonded to one silicon atom.
T: A silicon-containing bonding unit having three oxygen atoms bonded to one silicon atom and one hydrogen atom or monovalent organic group.
D: A silicon-containing bonding unit having two oxygen atoms bonded to one silicon atom and two hydrogen atoms or monovalent organic groups.
[The said organic group is a monovalent organic group whose atom couple | bonded with the silicon atom is a carbon atom.] The water repellent powder which has a structure represented by following General formula (1).

[In formula (1), R <^1> and R <^2> represents an alkyl group or an aryl group each independently, and R <^3> and R <^4> represents a alkylene group each independently.] Water-repellent powder which has a ladder structure provided with a support part and a bridge | crosslinking part, and the said bridge | crosslinking part is represented by following General formula (2).

[In formula (2), R <^5> and R <^6> represents an alkyl group or an aryl group each independently, and b shows the integer of 1-50.] The method of claim 4, wherein
The water repellent powder which has a ladder structure shown by following General formula (3).

[In formula (3), R <^5> , R <^6> , R <^7> and R <^8> respectively independently represents an alkyl group or an aryl group, a and c respectively independently represent the integer of 1-3000, b is an integer of 1-50 Is displayed.] The method according to any one of claims 1 to 5,
The water repellent powder whose average particle diameter D50 is 1-1000 micrometers.

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