JP5310549B2 - Coating liquid for forming low refractive index film, production method thereof and antireflection material - Google Patents

Abstract

Disclosed is a coating solution for forming a coating film, which can be cured at a low temperature even on a substrate having a high water contact angle, and can form a coating film having high light transmissivity, high hardness, excellent scratch resistance and a low refractive index. Also disclosed is a method for producing the coating solution. Further disclosed is an anti-reflection material utilizing the coating film. Specifically disclosed is a coating solution for forming a low refractive index coating film, which comprises: a polysiloxane (A) which has a silicon atom having a fluorinated organic group bound thereto; a linear alkylamine compound (B) having 20 or less carbon atoms; and an amine compound (C) which has 20 or less carbon atoms in total and has a cyclic group having 10 or less carbon atoms in its structure.

Description

  The present invention relates to a coating solution for forming a low refractive index film containing polysiloxane, a production method thereof, a low refractive index film formed from the coating solution, and an antireflection material having the coating film.

  Conventionally, it is known that when a coating having a refractive index smaller than that of the substrate is formed on the surface of the substrate, the reflectance of light reflected from the surface of the coating is lowered. And the low refractive index film which shows such a reduced light reflectance is utilized as a light reflection preventing film, and is applied to the surface of various base materials.

For example, Patent Document 1 discloses an alcohol dispersion of MgF ₂ fine particles produced by reacting a magnesium salt or an alkoxymagnesium compound as an Mg source with a fluoride salt as an F source, or an improvement in film strength. For this purpose, a solution obtained by adding tetraalkoxysilane or the like is used as a coating solution, which is coated on a glass substrate and heat-treated at a temperature of 100 to 500 ° C. to form an antireflection film exhibiting a low refractive index on the substrate. A method is disclosed.

  Further, Patent Document 2 discloses a hydrolytic polycondensate such as tetraalkoxysilane, which is a coating liquid obtained by mixing two or more kinds having different average molecular weights and a solvent such as alcohol to form a coating film. It is disclosed that a film is formed by adding means such as mixing ratio at the time of mixing and control of relative humidity. The coating is obtained by heating at a temperature of 250 ° C. or higher, exhibits a refractive index of 1.21 to 1.40, has micropits or irregularities having a diameter of 50 to 200 nm, and has a thickness of 60 to 160 nm. . A low reflection glass in which the coating is formed on a glass substrate is manufactured.

Patent Document 3 discloses a low reflectance glass comprising glass, a lower layer film having a high refractive index formed on the surface thereof, and an upper layer film having a low refractive index formed on the surface thereof. ing. The upper layer film is formed by using a fluorine-containing silicone compound having a polyfluorocarbon chain such as CF ₃ (CF ₂ ) ₂ C ₂ H ₄ Si (OCH ₃ ) ₃ and 5 to 90% by mass of Si (OCH ₃ ) ₄ with respect to this. A hydrolyzed silane coupling agent such as acetic acid in the presence of a catalyst such as acetic acid in an alcohol solvent at room temperature, and then applying a co-condensate solution prepared by filtration onto the lower layer film. This is performed by heating at 120 to 250 ° C.

Patent Document 4 discloses a silicon compound represented by Si (OR) ₄ , a silicon compound represented by CF ₃ (CF ₂ ) _n CH ₂ CH ₂ Si (OR ¹ ) ₃ , and R ² CH ₂ OH. A coating solution is disclosed in which a polysiloxane solution is produced by heating a reaction mixture containing the indicated alcohol and oxalic acid in a specific ratio at a temperature of 40 to 180 ° C. in the absence of water. A coating having a refractive index of 1.28 to 1.38 and a water contact angle of 90 to 115 degrees is formed by applying this coating solution to the surface of the substrate and thermosetting at a temperature of 80 to 450 ° C. .

JP 05-105424 A Japanese Patent Application Laid-Open No. 06-157076 Japanese Patent Laid-Open No. 61-010043 JP 09-208898 A

  In recent years, antireflection films used for various display devices such as the above are used for antireflection base materials used in the display devices such as liquid crystal and plasma, which are becoming larger, lighter and thinner. The prevention film has a tendency to reduce the thickness of the film for the purpose of weight reduction and high transparency, and therefore, the problem is that the damage caused by heat increases. Therefore, it is possible to obtain an antireflection substrate by low-temperature treatment that does not damage the film, and there has been an increasing demand for a coating solution for forming a thermosetting film that cures at a relatively low temperature. It was desired. However, the curing temperature of the conventional low refractive index coating as described above is not necessarily low enough, and it is desired to further lower the curing temperature.

Furthermore, the antireflection film used in the above various display devices has a coating film having a refractive index lower than that of the substrate on the surface of a film substrate such as a triacetyl cellulose film with a hard coat or a polyethylene terephthalate film with a hard coat. It is obtained by formation. In that case, depending on the material of the hard coat and the presence or absence of a surface treatment such as a hydrophilization treatment, the water contact angle of the surface of the base film forming the low refractive index film has various sizes. It is difficult to form a high hardness, low refractive index film having high scratch resistance on a substrate film having a high water contact angle.
Thus, an object of the present invention is to provide a coating solution that is excellent in storage stability, sufficiently cured by heat treatment at a low temperature, and can form a coating film having a low refractive index and excellent scratch resistance, an efficient production method thereof, An object of the present invention is to provide a coating obtained from a coating solution, and an antireflection material such as an antireflection film using the coating.

As a result of intensive studies to achieve the above object, the present inventors have found that a polysiloxane (A) having a silicon atom bonded with a fluorine-containing organic group and a linear alkylamine compound (B) having 20 or less carbon atoms. And a film obtained from a coating solution containing an amine compound (C) having a cyclic group having a total carbon number of 20 or less and a carbon number of 10 or less in the structure, and an organic solvent (D), It has been found that even a substrate having a high water contact angle exceeding 90 degrees is cured at a low temperature, and has a low refractive index excellent in high light transmission and high hardness and scratch resistance.
In the present invention, the mechanism of why the coating film formed from the coating solution has the above-mentioned excellent characteristics is not necessarily clear, but as illustrated in a later comparative example, In the case of a coating solution in which each of the above-described components is contained alone, a film having excellent storage stability, thermosetting at a low temperature, and having a low refractive index and excellent scratch resistance cannot be obtained. In the present invention, the linear alkylamine compound (B) having 20 or less carbon atoms and the amine compound (C) having an overall carbon number of 20 or less and having a cyclic group having 10 or less carbon atoms in the structure thereof are used. By combining various types of amine compounds, for the first time, a coating film having high hardness and excellent scratch resistance is provided.

（式中、Ｒ_１は炭素数３〜１０の環状基であり、Ｒ_２は単結合又は炭素数１〜１７のアルキレン基を表す。）
（６）有機溶媒（Ｄ）が、炭素数が１〜６のアルコール及び炭素数が３〜１０のグリコールエーテルからなる群から選ばれる少なくとも1種からなる上記（２）〜（５）のいずれかに記載の塗布液。
（７）ポリシロキサン（Ａ）がその有するケイ素原子の合計量を二酸化ケイ素に換算して０．１〜１５質量％含有され、アミン化合物（Ｂ）と、アミン化合物（Ｃ）が、いずれもポリシロキサン（Ａ）のケイ素原子の合計量の１モルに対して０．０１〜０．２モル含有される上記（１）〜（６）のいずれかに記載の塗布液。
（８）さらに、式（２）で表されるケイ素化合物（Ｄ）が含有される上記（１）〜（７）のいずれかに記載の塗布液。

（式中、Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４はそれぞれ独立に水素原子又は炭素数１〜５の飽和炭化水素基を表し、ｎは２以上の整数を表す。）
（９）上記（１）〜（８）のいずれかに記載の塗布液を硬化して得られる低屈折率被膜。
（１０）上記（９）に記載の低屈折率被膜が、該被膜よりもより高い屈折率を有する基材の表面上に形成された反射防止材。
（１１）含フッ素有機基が結合したケイ素原子を有するアルコキシシランを５〜４０モル％含み、かつ、濃度が全ケイ素原子を二酸化ケイ素に換算して有機溶媒中４〜１５質量％であるアルコキシシランの溶液を、上記アルコキシシランの全アルコキシド基の１モルに対して０．２〜２モルの蓚酸の存在下に縮重合してポリシロキサン（Ａ）の溶液を得る工程と、得られたポリシロキサン（Ａ）の溶液に対し、炭素数が２０以下の直鎖アルキルアミン化合物（Ｂ）と、全体の炭素数が２０以下でありかつその構造中に炭素数１０以下の環状基を有するアミン化合物（Ｃ）と有機溶媒（Ｄ）の混合溶液を混合する工程と、を含むことを特徴とする低屈折率被膜形成用塗布液の製造方法。Thus, the present invention has a gist characterized by the following.
(1) a polysiloxane (A) having a silicon atom to which a fluorine-containing organic group is bonded, a linear aliphatic amine compound (B) having 20 or less carbon atoms, and a total carbon number of 20 or less; A coating solution for forming a low refractive index film, comprising: an amine compound (C) having a cyclic group having 10 or less carbon atoms in its structure.
(2) The coating solution according to (1) above, wherein the polysiloxane (A), the aliphatic amine compound (B), and the amine compound (C) are dissolved in the organic solvent (D).
(3) The coating liquid according to the above (1) or 2, wherein the polysiloxane (A) has 5 to 40 mol% of silicon atoms bonded with fluorine-containing organic groups with respect to all the silicon atoms.
(4) The coating solution according to any one of (1) to (3), wherein the aliphatic amine compound (B) is a primary amine.
(5) The coating solution for forming a low refractive index film according to any one of (1) to (4), wherein the amine compound (C) is represented by the following formula (1).

(In the formula, R ₁ represents a cyclic group having 3 to 10 carbon atoms, and R ₂ represents a single bond or an alkylene group having 1 to 17 carbon atoms.)
(6) Any of the above (2) to (5), wherein the organic solvent (D) comprises at least one selected from the group consisting of alcohols having 1 to 6 carbon atoms and glycol ethers having 3 to 10 carbon atoms. The coating solution as described in 1.
(7) The total amount of silicon atoms contained in the polysiloxane (A) is 0.1 to 15% by mass in terms of silicon dioxide, and the amine compound (B) and the amine compound (C) are both poly Coating liquid in any one of said (1)-(6) contained 0.01-0.2 mol with respect to 1 mol of the total amount of the silicon atom of siloxane (A).
(8) The coating solution according to any one of (1) to (7), further containing a silicon compound (D) represented by the formula (2).

(In the formula, R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a saturated hydrocarbon group having 1 to 5 carbon atoms, and n represents an integer of 2 or more.)
(9) A low refractive index film obtained by curing the coating liquid according to any one of (1) to (8).
(10) An antireflection material, wherein the low refractive index film according to (9) is formed on the surface of a substrate having a higher refractive index than the film.
(11) An alkoxysilane containing 5 to 40 mol% of an alkoxysilane having a silicon atom to which a fluorine-containing organic group is bonded, and having a concentration of 4 to 15% by mass in an organic solvent when all silicon atoms are converted to silicon dioxide A polysiloxane (A) solution by polycondensation in the presence of 0.2 to 2 moles of oxalic acid with respect to 1 mole of all alkoxide groups of the alkoxysilane, and the resulting polysiloxane A linear alkylamine compound (B) having 20 or less carbon atoms and an amine compound having a total carbon number of 20 or less and a cyclic group having 10 or less carbon atoms in the structure of the solution (A) ( C) and the process of mixing the organic solvent (D) mixed solution, The manufacturing method of the coating liquid for low refractive index film formation characterized by the above-mentioned.

According to the present invention, it is possible to provide a coating liquid for forming a film that has excellent storage stability, for example, is sufficiently cured by a low-temperature heat treatment at a temperature of 20 to 70 ° C., and has a low refractive index and excellent scratch resistance.
And the film obtained from the coating liquid for film formation of this invention can be used suitably for antireflection materials, such as an antireflection film.

The present invention is described in further detail below.
<Polysiloxane (A)>
A polysiloxane having silicon atoms in the main skeleton, to which fluorine-containing organic groups are bonded, which is contained in the coating solution for forming a low refractive index film of the present invention (hereinafter also simply referred to as coating solution for forming a film or coating solution). (A) (hereinafter also simply referred to as polysiloxane (A)) is an organic group bonded to a silicon atom in the main skeleton and substituted with a fluorine atom (referred to as a fluorine-containing organic group in the present invention). In other words, it is a polysiloxane having a site in which an organic side chain substituted with a fluorine atom is bonded to a silicon atom.
As the above-mentioned fluorine-containing organic group, an organic group partially or entirely substituted with fluorine, usually an alkyl group in which some hydrogen atoms are substituted with fluorine atoms, or some hydrogen atoms are substituted with fluorine atoms In many cases, it is an alkyl group containing an ether bond. The number of fluorine atoms that the fluorine-containing organic group has is not particularly limited.

When the carbon number of the fluorine-containing organic group exceeds 15, the solubility in an organic solvent (D) described later may be insufficient. Therefore, 3-15 are preferable, as for carbon number of a fluorine-containing organic group, 3-12 are more preferable, and 3-10 are especially preferable. Examples of the fluorine-containing organic group include, but are not limited to, a trifluoropropyl group, a tridecafluorooctyl group, a heptadecafluorodecyl group, a pentafluorophenylpropyl group, and the like.
Among the fluorine-containing organic groups, the fluorine-containing alkyl group is preferable because a highly transparent film can be easily obtained, and the carbon number thereof is preferably 3 to 15, more preferably 3 to 12, and particularly preferably 3 to 10. Specific examples thereof include a trifluoropropyl group, a tridecafluorooctyl group, a heptadecafluorodecyl group, and the like.
The polysiloxane (A) may have one or more kinds of fluorine-containing organic groups as described above.

  The polysiloxane (A) is not particularly limited as long as it can form a homogeneous solution in the coating solution. In particular, when the silicon atom to which the above-mentioned fluorine-containing organic group is bonded is 5 to 40 mol% in the total silicon atoms of the polysiloxane (A), a film having a water contact angle of 90 degrees or more is easily obtained, This is preferable because a homogeneous polysiloxane (A) solution can be easily obtained. Furthermore, it is preferable that the silicon atom bonded with the fluorine-containing organic group is 10 to 40 mol% in the total silicon atoms of the polysiloxane (A) because the reflectance can be further reduced. Moreover, when the silicon atom which couple | bonded the fluorine-containing organic group is 5-25 mol% in all the silicon atoms of polysiloxane (A), since abrasion resistance can be made higher, it is preferable. In view of the reflectance and scratch resistance, the silicon atom bonded with the fluorine-containing organic group is particularly preferably 10 to 25 mol in the total silicon atoms of the polysiloxane (A).

  The method for obtaining the polysiloxane (A) having a fluorine-containing organic group is not particularly limited. Generally, it is obtained by polycondensation of the above-mentioned alkoxysilane having a fluorine-containing organic group, or the alkoxysilane and another alkoxysilane. Among these, when polycondensation of alkoxysilane having a fluorine-containing organic group and tetraalkoxysilane and further alkoxysilane other than the above is preferable, a stable and homogeneous solution of polysiloxane (A) is easily obtained. .

かかるアルコキシシランの具体例としては、トリフルオロプロピルトリメトキシシラン、トリフルオロプロピルトリエトキシシラン、トリデカフルオロオクチルトリメトキシシラン、トリデカフルオロオクチルトリエトキシシラン、ヘプタデカフルオロデシルトリメトキシシラン、ヘプタデカフルオロデシルトリエトキシシラン等が挙げられる。
また、含フッ素有機基を持つアルコキシシランと縮重合されるテトラアルコキシシランの具体例としては、テトラメトキシシラン、テトラエトキシシラン、テトラプロポキシシラン、テトライソプロポキシシラン、テトラブトキシシラン等が挙げられる。Examples of the alkoxysilane having a fluorine-containing organic group include alkoxysilanes represented by the following formula (3). In the formula, R ¹ is a fluorine-containing organic group, and R ² is a hydrocarbon group having preferably 1 to 5 carbon atoms.

Specific examples of such alkoxysilanes include trifluoropropyltrimethoxysilane, trifluoropropyltriethoxysilane, tridecafluorooctyltrimethoxysilane, tridecafluorooctyltriethoxysilane, heptadecafluorodecyltrimethoxysilane, heptadecafluoro. Examples include decyltriethoxysilane.
Specific examples of tetraalkoxysilane that is polycondensed with alkoxysilane having a fluorine-containing organic group include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, and tetrabutoxysilane.

Other alkoxysilanes other than tetraalkoxysilane that are polycondensed with alkoxysilanes having fluorine-containing organic groups are alkoxysilanes in which organic groups other than fluorine-containing organic groups and / or hydrogen atoms are bonded to silicon atoms. Specific examples thereof are listed below. Trimethoxysilane, triethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, butyltrimethoxysilane, butyltriethoxysilane, pentyltri Methoxysilane, pentyltriethoxysilane, heptyltrimethoxysilane, heptyltriethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, Octadecyltrimethoxysilane, octadecyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, vinyl Limethoxysilane, vinyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyl Trialkoxysilanes such as trimethoxysilane and γ-methacryloxypropyltriethoxysilane, dialkoxysilanes such as dimethyldimethoxysilane and dimethyldiethoxysilane, and trialkylalkoxysilanes such as trimethylmethoxysilane and trimethylethoxysilane.
Other alkoxysilanes may be used alone or in combination of two or more.

  The amount of the alkoxysilane having a fluorine-containing organic group used to obtain the polysiloxane (A) is such that the polysiloxane (A) is in a homogeneous solution state in the organic solvent (D), and the effect of the present invention is impaired. It is not limited as long as it is not. In particular, when the alkoxysilane having a fluorine-containing organic group is 5 to 40 mol% of the total alkoxysilane, it is easy to obtain a film having a contact angle of water of 90 degrees or more, and a homogeneous polysiloxane (A) solution It is preferable because it is easy to obtain. Moreover, when the alkoxysilane having a fluorine-containing organic group is 10 to 40 mol% of the total alkoxysilane, the reflectance can be further reduced, which is preferable. Moreover, when the alkoxysilane having a fluorine-containing organic group is 5 to 25 mol% of the total alkoxysilane, it is preferable because scratch resistance can be further increased. In view of the reflectance and scratch resistance, the alkoxysilane having a fluorine-containing organic group is particularly preferably 10 to 25 mol% of the total alkoxysilane.

As a method for obtaining a polysiloxane (A) having a fluorine-containing organic group, for example, an alkoxysilane having a fluorine-containing organic group and, if necessary, an organic solution of tetraalkoxysilane and another alkoxysilane in the presence of oxalic acid. And a method of polycondensation by heating. Specifically, after adding succinic acid to alcohol in advance to obtain an alcohol solution of succinic acid, the above-mentioned various alkoxysilanes are mixed while the solution is heated.
The amount of succinic acid present is preferably 0.2 to 2 mol with respect to 1 mol of all alkoxy groups of the alkoxysilane used. The heating can be performed at a liquid temperature of preferably 0 to 180 ° C., and preferably several tens of times under reflux in a container equipped with a reflux pipe so that the liquid does not evaporate or volatilize. It takes about 10 to 10 hours.

In the case of obtaining the polysiloxane (A) having the fluorine-containing organic group, when a plurality of alkoxysilanes are used, a mixture in which alkoxysilanes are mixed in advance may be used. It may be added.
In the case of polycondensation of alkoxysilane, the concentration in which all silicon atoms of alkoxysilane in the organic solvent are converted into oxides (hereinafter referred to as SiO ₂ conversion concentration) is preferably 20% by mass or less, and particularly preferably 4%. It is preferable to heat in the range of ˜15% by mass. By selecting such a concentration range, gel formation can be suppressed and a homogeneous polysiloxane (A) solution can be obtained.

  The organic solvent (hereinafter also referred to as a polymerization solvent) used when polycondensing the alkoxysilane is not particularly limited as long as it dissolves the alkoxysilane. In general, since an alcohol is generated by a polycondensation reaction of an alkoxysilane, an alcohol or an organic solvent having good compatibility with the alcohol is used. In particular, alcohols, glycols, or glycol ethers are preferable. Specific examples of such a polymerization solvent include alcohols such as methanol, ethanol, propanol, and n-butanol, glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether. It is done. A plurality of the above organic solvents may be mixed and used.

In the present invention, for the polysiloxane (A) having a fluorine-containing organic group, the solution obtained by the above-described method may be used as it is as the polysiloxane (A) solution, or if necessary, by the above-described method. The obtained solution may be concentrated, diluted by adding a solvent (hereinafter also referred to as a dilution solvent), or substituted with another solvent to obtain a polysiloxane (A) solution.
When substituting with another solvent, the solvent (hereinafter, also referred to as “substitution solvent”) may be the same solvent used for polycondensation or may be another solvent. The solvent is not particularly limited as long as the polysiloxane (A) is uniformly dissolved, and one kind or plural kinds of solvents can be arbitrarily selected and used.

  Specific examples of the substitution solvent and the dilution solvent include alcohols such as methanol, ethanol, isopropanol, butanol and diacetone alcohol; ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; ethylene glycol, propylene glycol, hexylene glycol and the like. Glycols such as methyl cellosolve, ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, glycol ethers such as diethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether; acetic acid methyl ester, acetic acid ethyl ester, lactate ethyl ester, etc. And the like.

<Amine compound (B)>
The linear aliphatic amine compound (B) having 20 or less carbon atoms (also referred to as amine compound (B) in the present invention) contained in the coating liquid of the present invention has 2 to 20 carbon atoms, Preferably, it is a linear aliphatic amine compound having 2 to 8 carbon atoms. This amine compound (B) is preferably a linear alkylamine. The amine compound (B) is preferably a primary amine. In the case of an amine compound having 20 or more carbon atoms, the solubility may be remarkably lowered, and the refractive index may be increased. For this reason, those having a small number of carbon atoms are preferred.

The amine compound _{(B), CH 3 CH 2} NH 2, CH 3 (CH 2) 2 NH 2, CH 3 (CH 2) 3 NH 2, CH 3 (CH 2) 4 NH 2, CH 3 (CH 2 ) ₅ NH ₂ , CH ₃ (CH ₂ ) ₆ NH ₂ , CH ₃ (CH ₂ ) ₇ NH ₂ , CH ₃ (CH ₂ ) ₈ NH ₂ , CH ₃ (CH ₂ ) ₉ NH ₂ , CH ₃ (CH ₂ ) ₁₀ NH ₂ , CH ₃ (CH ₂ ) ₁₁ NH ₂ , CH ₃ (CH ₂ ) ₁₂ NH ₂ , CH ₃ (CH ₂ ) ₁₃ NH ₂ , CH ₃ (CH ₂ ) ₁₄ NH ₂ , CH ₃ (CH ₂ ) ₁₅ NH ₂ , CH ₃ (CH ₂ ) ₁₆ NH ₂ , CH ₃ (CH ₂ ) ₁₇ NH ₂ , CH ₃ (CH ₂ ) ₁₈ NH ₂ , CH ₃ (CH ₂ ) ₁₉ NH ₂ , OHCH ₂ NH ₂ , OH (CH ₂ ) ₂ NH ₂ , OH (CH ₂ ) ₃ NH ₂ , OH (CH ₂ ) ₄ NH ₂ , OH (CH ₂ ) ₅ NH ₂ , OH (CH ₂ ) ₆ NH ₂ , OH (CH ₂ ) ₇ NH ₂ , OH (CH ₂ ) ₈ NH ₂ , OH (CH ₂ ) ₉ NH ₂ , OH (CH ₂ ) ₁₀ NH ₂ , OH (CH ₂ ) ₁₁ NH ₂ , OH (CH ₂ ) ₁₂ NH ₂ , OH (CH ₂ ) ₁₃ NH ₂ , OH (CH ₂ ) ₁₄ NH ₂ , OH (CH ₂ ) ₁₅ NH ₂ , OH (CH ₂ ) ₁₆ NH ₂ , OH (CH ₂ ) ₁₇ NH ₂ , OH (CH ₂ ) ₁₈ NH ₂ , _{OH (CH 2) 19 NH 2} , OH (CH 2) 20 NH 2 , and the like. The amine compound (B) is preferably a linear aliphatic primary amine. The amine compound (B) is preferably a linear primary amino alcohol, and particularly preferably monoethanolamine.

<Amine compound (C)>
The amine compound (C) contained in the coating solution of the present invention having a total carbon number of 20 or less and having a cyclic group having a carbon number of 10 or less in its structure (also referred to as amine compound (C) in the present invention) .) Is preferably a primary amine having a total carbon number of 20 or less, preferably 3 to 12, and having a cyclic group having 10 or less carbon atoms, preferably 3 to 10 carbon atoms in its structure. The cyclic group mentioned here means an aromatic ring or aliphatic ring such as benzene or naphthalene, but the amine compound (C) preferably has an aliphatic ring structure.

式(１)中、Ｒ_１は炭素数３〜１０、好ましくは３〜１２の環状基である。Ｒ_２は単結合又は炭素数１〜１７、好ましくは１〜３のアルキレン基を表す。
本発明において、アミン化合物（Ｃ）の好ましい具体例としては、下記の式（Ａ−１）から（Ａ−１０）等の化合物が挙げられる。特に、式（Ａ−４）、（Ａ−５）、又は（Ａ−６）の化合物が好ましい。

In the present invention, the amine compound (C) is preferably represented by the following formula (1).

In the formula (1), R ₁ is a cyclic group having 3 to 10 carbon atoms, preferably 3 to 12 carbon atoms. R ₂ represents a single bond or an alkylene group having 1 to 17 carbon atoms, preferably 1 to 3 carbon atoms.
In the present invention, preferred specific examples of the amine compound (C) include compounds such as the following formulas (A-1) to (A-10). In particular, the compound of Formula (A-4), (A-5), or (A-6) is preferable.

The amine compound (B) and the amine compound (C) may be used in the form of a salt such as an organic acid salt. In this case, the stability of the coating solution may be improved.
In addition, the amine compound (B) and the amine compound (C) in the present invention have a high effect of accelerating the curing of the film without causing rapid gelation. Furthermore, the amine compound (B) can easily obtain a sufficient film forming property on a substrate having a high water contact angle.
In addition, it is preferable to use an amine compound (C) having an aliphatic ring structure because an increase in refractive index can be suppressed.

  The content of the amine compound (B) and the amine compound (C) in the coating solution of the present invention is 1 mol of the total amount of all silicon atoms of the polysiloxane (A), and the amine compound (B) and the amine compound (C). ) Is preferably 0.01 to 0.2 mol, more preferably 0.03 to 0.1 mol. When both the amine compound (B) and the amine compound (C) are 0.01 mol or more, it is preferable because they are easily cured at a low temperature, and conversely, when the amount is 0.2 mol or less, the coating is transparent and has no unevenness. It is preferable because high film hardness is easily obtained. In particular, it is preferable to use the amine compound (B) and the amine compound (C) in the same number of moles because the hardness is good.

<Organic solvent (D)>
The organic solvent (D) which is the main solvent of the coating liquid of the present invention includes a polysiloxane (A) in which a fluorine-containing organic group is bonded to a silicon atom, an amine compound (B), an amine compound (C), and Any silicon compound (E), which will be described later, can be used as long as it dissolves the other components.
Preferred specific examples of the organic solvent (D) include aliphatic alcohols such as methanol, ethanol, isopropanol, butanol and diacetone alcohol; alicyclic alcohols such as cyclopentyl alcohol, cyclohexanol; benzyl alcohol, cinnamyl alcohol and the like. Aromatic alcohols; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone; glycols such as ethylene glycol, propylene glycol, hexylene glycol; methyl cellosolve, ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, diethylene glycol monomethyl ether , Glycol ethers such as propylene glycol monomethyl ether and propylene glycol monobutyl ether; acetic acid Chiruesuteru, ethyl acetate, and the like esters such as ethyl lactate ester. These single or plural organic solvents are used in combination.
Among them, it is preferably composed of at least one selected from the group consisting of an alcohol having 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms, and preferably a glycol ether having 3 to 10 carbon atoms, more preferably 3 to 7 carbon atoms. Is preferred.

<Silicon compound (E)>
The coating liquid for forming a low refractive index film of the present invention preferably further contains a silicon compound (E) represented by the following formula (2). Thereby, the abrasion resistance of a film can further be improved.

式（２）における、Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４は、それぞれ独立に水素原子又は炭素数が好ましくは１〜５の飽和炭化水素基を表し、ｎは２以上、好ましくは２〜５０の整数を表す。炭素数１〜５の飽和炭化水素基の具体例としては、メチル基、エチル基、プロピル基、ブチル基などが挙げられる。
ケイ素化合物（Ｅ）は、式（２）で表される化合物の複数種が混合したものでもよい。その場合、ｎが２以上の整数であることが好ましく、より好ましくは４以上の整数である。

In the formula (2), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a saturated hydrocarbon group having preferably 1 to 5 carbon atoms, and n is 2 or more, preferably 2 to 2 Represents an integer of 50. Specific examples of the saturated hydrocarbon group having 1 to 5 carbon atoms include a methyl group, an ethyl group, a propyl group, and a butyl group.
The silicon compound (E) may be a mixture of a plurality of compounds represented by the formula (2). In that case, n is preferably an integer of 2 or more, more preferably an integer of 4 or more.

Although the method to obtain the said silicon compound (E) is not specifically limited, For example, it can obtain by the method of hydrolyzing and condensing tetraalkoxysilane in organic solvents, such as alcohol. At that time, the hydrolysis may be either partial hydrolysis or complete hydrolysis. In the case of complete hydrolysis, theoretically, it is sufficient to add 0.5 moles of water of all alkoxide groups in the tetraalkoxysilane, but it is usually preferable to add an excess amount of water over 0.5 moles. On the other hand, in the case of partial hydrolysis, the amount of water is 0.5 times mol or less, but 0.2 to 0.5 times mol is preferable.
Specific examples of the tetraalkoxysilane as the raw material include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetrabutoxysilane, and are easily available as commercial products.

  The amount of water used in the reaction for obtaining the silicon compound (E) can be appropriately selected as desired, but is preferably 0.5 to 2.5 moles of all alkoxide groups in the tetraalkoxysilane. In addition, in the reaction, for the purpose of promoting hydrolysis / condensation reaction, acids such as hydrochloric acid, sulfuric acid, nitric acid, acetic acid, formic acid, oxalic acid, phosphoric acid, hydrofluoric acid, maleic acid, alkalis such as ammonia, hydrochloric acid, sulfuric acid, A catalyst such as a metal salt such as nitric acid is used. It is also common to further promote polycondensation by heating a solution in which alkoxysilane is dissolved. At that time, the heating temperature and the heating time can be appropriately selected as desired. For example, heating and stirring at room temperature to 100 ° C. for 0.5 to 48 hours, heating and stirring for 0.5 to 48 hours under reflux, etc. Is mentioned.

In the above reaction, the organic solvent used for polycondensation of tetraalkoxysilane is not particularly limited as long as it dissolves tetraalkoxysilane. In general, since an alcohol is generated by a polycondensation reaction of tetraalkoxysilane, an alcohol or an organic solvent having good compatibility with the alcohol is used.
Specific examples of such organic solvents include alcohols such as methanol, ethanol, propanol, and n-butanol, glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether. It is done. A plurality of the above organic solvents may be mixed and used.

The organic compound solution of the silicon compound (E) thus obtained has a SiO ₂ equivalent concentration of preferably 30% by mass or less. By selecting an arbitrary concentration within this concentration range, gel formation can be suppressed and a homogeneous solution can be obtained.
In addition, as a silicon compound (E), a commercial item can also be used. For example, methyl silicate 51, methyl silicate 53A, ethyl silicate 40, ethyl silicate 48, SS-C1 etc. which are all made from Colcoat are mentioned.

<Other ingredients>
The coating liquid for forming a low refractive index film of the present invention includes polysiloxane (A), amine compound (B), amine compound (C), organic solvent (D), and silicon compound as long as the effects of the present invention are not impaired. Other components other than (E), for example, inorganic fine particles, leveling agents, surfactants, and media such as water may be contained.
As the inorganic fine particles, fine particles such as silica, alumina, titania, and magnesium fluoride are preferable. A colloidal solution is particularly preferred. This colloidal solution may be a dispersion of inorganic fine particle powder in a dispersion medium or a commercially available colloidal solution.

By adding inorganic fine particles to the coating liquid of the present invention, it is possible to impart the surface shape of the formed cured film and other functions. As the inorganic fine particles, the average particle diameter is preferably 0.001 to 0.2 μm, more preferably 0.001 to 0.1 μm. When the average particle diameter of the inorganic fine particles exceeds 0.2 μm, the transparency of the cured film formed by the coating liquid may be lowered.
The inorganic fine particles are preferably added as a colloidal solution dispersed in a dispersion medium. Examples of the dispersion medium for the colloidal solution include water and organic solvents. From the viewpoint of the stability of the coating solution, the colloid solution preferably has a pH or pKa of 2 to 10, particularly 3 to 7.

Examples of the organic solvent for the dispersion medium of the colloidal solution include alcohols such as methanol, isopropyl alcohol, ethylene glycol, butanol and ethylene glycol monopropyl ether; ketones such as methyl ethyl ketone and methyl isobutyl ketone; aromatic carbonization such as toluene and xylene. Examples include hydrogens; amides such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone; esters such as ethyl acetate, butyl acetate, and γ-butyrolactone; and ethers such as tetrahydrofuran and 1,4-dioxane. .
Of these, alcohols or ketones are preferable. These organic solvents can be used alone or in admixture of two or more as a dispersion medium.
In addition, as the leveling agent and surfactant, known ones can be used, and commercially available products are particularly preferred because they are easily available.

<Coating liquid for film formation>
The coating liquid for forming a film of the present invention contains a polysiloxane (A), a linear alkylamine (B), an amine compound (C), and, if necessary, a silicon compound (E) and other components, and these are organic. It is a solution dissolved in a solvent. As an organic solvent, the organic solvent (D) mentioned above is preferable. In the present invention, the preparation method is not limited as long as the coating solution is obtained. For example, the polysiloxane (A), the amine compound (B), the amine compound (C), and the silicon compound (E) used as necessary and other components are sequentially added and mixed in an organic solvent. In this case, the order of adding each component is not particularly limited. Moreover, you may mix each solution which melt | dissolved in the organic solvent which each uses said each component. In particular, when the polysiloxane (A) solution is mixed with the mixed solution of the amine compound (B), the amine compound (C) and the organic solvent (D), generation of precipitates can be suppressed, which is preferable.

  Among these, when the polysiloxane (A) is obtained as an organic solvent solution, the polysiloxane (A) solution can be used as it is, which is preferable. When the polysiloxane (A) is obtained as an organic solvent solution, as described above, the organic solvent solution of the alkoxysilane having a silicon atom to which the fluorine-containing organic group is bonded is added to 1 mol of the alkoxide group of the alkoxysilane. Preferably, it is obtained by condensation polymerization in the presence of 0.2 to 2 mol of oxalic acid.

In the coating solution of the present invention, an acid can be mixed in advance with the polysiloxane (A) solution for the purpose of adjusting the pH. The amount of the acid is preferably 0.01 to 2.5 mol, more preferably 0.1 to 2 mol with respect to 1 mol of the silicon atom of the polysiloxane (A).
As the acid used above. Inorganic acids such as hydrochloric acid, nitric acid, sulfuric acid and phosphoric acid; monocarboxylic acids such as formic acid, acetic acid and malic acid; and organic acids such as polycarboxylic acids such as oxalic acid, citric acid, propionic acid and succinic acid. Among these, the acid in the solution state can be used as it is, but it is preferable to dilute with a polymerization solvent. It is preferable to use other acids by dissolving them in an appropriate concentration in the polymerization solvent.

In the coating liquid of the present invention, the polysiloxane (A) is preferably 0.1 to 15% by mass, more preferably 0.5 to 0.5% by converting the silicon atom of the polysiloxane (A) into silicon dioxide. It is contained in an amount of 10% by mass, and the amine compound (B) and the amine compound (C) are each preferably from 0.01 to 0.2 mol, more preferably from 0.001 mol to 1 mol of the silicon atom of the polysiloxane (A). It is contained in an amount of 03 to 0.1 mol.
Moreover, when a silicon compound (E) is contained, the silicon compound (E) is preferably 0.03 to 0.55 mol, more preferably 0.03 mol per mol of silicon atoms of the polysiloxane (A). It is suitable to contain 0.5-0.45 mol.

In the present invention, the SiO ₂ in terms of solid content concentration of the film-forming coating solution, preferably preferred that 0.1 to 15 wt%, more preferably from 0.5 to 10 mass%. When the SiO ₂ concentration is lower than 0.1% by mass, it is difficult to obtain a desired film thickness by a single application, and when it is 15% by mass or less, the pot life of the solution is more stable. The concentration in terms of SiO ₂ solid content referred to here means the concentration in which silicon atoms in the coating solution are converted to silicon dioxide. For example, in the case where only the polysiloxane (A) is contained in the coating solution, it means the concentration obtained by converting the silicon atom of the polysiloxane (A) into silicon dioxide, and the polysiloxane (A) is contained in the coating solution. When the silicon compound (E) is contained, it means a concentration obtained by converting the total amount of silicon atoms of the polysiloxane (A) and the silicon compound (E) into silicon dioxide.
The above-mentioned coating solution is prepared so that an organic solvent is added and the SiO ₂ solid content equivalent concentration is in the above range as necessary, and the organic solvent used for this manufactures polysiloxane (A). The organic solvent used for the polycondensation of the alkoxysilane during the treatment, the organic solvent used when the polysiloxane (A) solution is concentrated, diluted, or substituted with another organic solvent can be used. One or more organic solvents can be arbitrarily selected and used.

Specific examples of the coating solution for forming a low refractive index film in the present invention are given below.
[1] A coating solution containing polysiloxane (A), amine compound (B), and amine compound (C).
[2] A coating solution containing polysiloxane (A), amine compound (B), amine compound (C) and silicon compound (E).
[3] A coating liquid containing inorganic fine particles in the above [1] or [2].
[4] A coating solution containing a leveling agent or a surfactant in the above [1], [2] or [3].
[5] A coating solution in which the above [1] or [2] or [3] or [4] is dissolved in an organic solvent.

<Formation of low refractive index film>
The coating liquid for forming a film of the present invention can be applied to a substrate and thermally cured to obtain a desired film. A known or well-known method can be adopted as the coating method. For example, methods such as a dip method, a flow coating method, a spray method, a bar coating method, a gravure coating method, a roll coating method, a blade coating method, and an air knife coating method can be employed.
Examples of the base material include base materials made of plastic, glass, ceramics and the like. Plastics include polycarbonate, poly (meth) acrylate, polyethersulfone, polyarylate, polyurethane, polysulfone, polyether, polyetherketone, polytrimethylpentene, polyolefin, polyethylene terephthalate, poly (meth) acrylonitrile, triacetylcellulose, Examples thereof include sheets and films of diacetyl cellulose and acetate butyrate cellulose.

In the present invention, a substrate having a high water contact angle, for example, a substrate that has not been subjected to a treatment for enhancing hydrophilicity such as a saponification treatment, that is, a substrate having a surface with a high water contact angle of, for example, 90 degrees or more. Even when it is used, it is possible to form a low refractive index film having a high light transmittance and excellent scratch resistance and a refractive index of preferably 1.4 or less on the surface of the substrate.
The thickness of the coating film formed on the surface of the substrate can be adjusted also by the thickness of the coating film, but can also be easily adjusted by adjusting the SiO ₂ equivalent concentration of the coating solution.

The coating film formed on the substrate may be heat-cured as it is at a temperature of 20 to 70 ° C., but prior to this, it may be dried at a temperature of 20 to 70 ° C. and then heat-cured. At that time, the time required for drying is preferably 10 seconds to 12 minutes.
The time required for thermosetting can be appropriately selected according to the desired film properties, but is usually 1 hour to 10 days. When a low curing temperature is selected, it is easy to obtain a coating film having sufficient scratch resistance by increasing the curing time.
Moreover, the coating liquid for forming a water-repellent film of the present invention can provide a film having excellent scratch resistance even at a curing temperature exceeding 70 ° C. At that time, it is preferable to adjust the curing temperature and the curing time in accordance with the heat-resistant temperature of the substrate.

<Applications such as antireflection materials>
Since the coating film formed from the coating liquid of the present invention has a low refractive index of, for example, 1.4 or less as described above, it can be suitably used particularly as an antireflection material. .
When the coating of the present invention is used for an antireflection material, the antireflection ability can be easily imparted by forming the coating of the present invention on a substrate having a higher refractive index than the coating of the present invention. That is, an antireflection substrate such as an antireflection film or an antireflection glass is formed by forming the coating of the present invention on the surface of a substrate such as a plastic film or glass having a higher refractive index than the coating of the present invention. Can do.
The film of the present invention is effective even when formed as a single film on the surface of the substrate, but a laminated structure in which the film of the present invention is formed on a film that forms one or more lower layers having a high refractive index. It is also effective as an antireflection body having

The coating of the present invention can be suitably used in fields where antireflection of light is desired, such as televisions, glass cathode ray tubes, computer displays, mirrors having a glass surface, and glass showcases.
Furthermore, since the coating film of the present invention has a water contact angle of 90 degrees or more, it has water repellency and has sufficient practicality in terms of antifouling property that fingerprints and oil-based inks can be easily wiped off. Since it can be sufficiently cured even in a curing process at a relatively low temperature of 20 to 70 ° C., it is very advantageous in the production process of an antireflection substrate.
Since the film of the present invention has the above-mentioned advantages, it is particularly useful for an antireflection film for display devices such as liquid crystal and plasma and display monitors.

EXAMPLES Hereinafter, although a synthesis example, an Example, and a comparative example are shown and this invention is demonstrated concretely, this invention is restrict | limited to the following synthesis example and Example, and is not interpreted.
Abbreviations in this example are as follows.
TEOS: Tetraethoxysilane FS-13: Tridecafluorooctyltrimethoxysilane MEA: Monoethanolamine HA: Hexylamine CHA: Cyclohexylamine AMCH: Aminomethylcyclohexane CPA: Cyclopropylamine COA: Cyclooctylamine BA: Benzylamine IPA: Isopropanol cHexOH: cyclohexanol PGME: propylene glycol monomethyl ether

Measurement methods in the following synthesis examples are shown below.
[Measurement of residual alkoxysilane monomer]
The residual alkoxysilane monomer in the polysiloxane (A) solution was measured by gas chromatography (hereinafter referred to as GC).
The GC measurement was performed under the following conditions using Shimadzu GC-14B manufactured by Shimadzu Corporation.
Column: Capillary column CBP1-W25-100 (length 25 mm, diameter 0.53 mm, wall thickness 1 μm)
Column temperature: The temperature was raised from a starting temperature of 50 ° C. at 15 ° C./min to reach an ultimate temperature of 290 ° C. (3 minutes).
Sample injection volume: 1 μL, injection temperature: 240 ° C., detector temperature: 290 ° C., carrier gas: nitrogen (flow rate 30 mL / min), detection method: FID method.

[Synthesis Example 1]
A 4-necked reaction flask equipped with a reflux tube was charged with 47.67 g of ethanol, 0.27 g of oxalic acid, and 16.20 g of pure water, and 43.74 g of TEOS and 42.12 g of FS-13 were added with stirring to obtain a mixed solution. Was prepared. The solution was then heated to reflux for 3 hours and then allowed to cool to room temperature to prepare a polysiloxane solution (PS). When this polysiloxane solution (PS) was measured by GC, no alkoxysilane monomer was detected.

[Examples 1 to 4, Comparative Examples 1 to 6]
With the composition shown in Table 1, the polysiloxane solution obtained in the above synthesis example, an amine compound, and an organic solvent were mixed to prepare a coating liquid for forming a film (Q1 to Q10).
Moreover, in the comparative example, the coating liquid (T1-T3) was prepared with the composition shown in Table 1.
About these Q1-Q10 and T1-T3 or the coating film using them, evaluation shown below was performed.

<Storage stability>
The coating solution for coating formation was allowed to stand at a temperature of 25 ° C. for 1 month, and then filtered through a non-aqueous polytetrafluoroethylene filter having a pore diameter of 0.45 μm, an inner diameter of 18 mm, and a length of 22 mm (Chromatodisc 13N, Kurashiki Boseki Co., Ltd.) Those that can be filtered are indicated by ◯, and those that are clogged are indicated by ×. The results are shown in Table 2.

<Evaluation of cured film>
The coating liquid for forming a film (Q1 to Q10 and T1 to T3) is a triacetyl cellulose (hereinafter referred to as HC-TAC) film with a hard coat (film thickness is 80 μm, the water contact angle of the hard coat surface is 83 degrees, A bar coater (No. 6) was applied to a reflectance of 4.5% at a wavelength of 550 nm to form a coating film. After leaving at a temperature of 23 ° C. for 30 seconds, it was dried in a clean oven at 60 ° C. for 10 minutes and then cured at a temperature of 60 ° C. for 1 week. About the obtained hardened film, water contact angle, oil-based pen wiping property, fingerprint wiping property, adhesion, reflectance, and scratch resistance were evaluated.

The refractive index was measured using a cured film formed as follows. The prepared coating solutions (Q1 to Q10 and T1 to T3) are spin-coated on a silicon wafer to form a coating film, and then cured on a hot plate at 100 ° C. for 30 minutes to form a cured film having a thickness of 100 nm. Obtained.
These evaluation methods are as follows, and the evaluation results are shown in Tables 2 and 3.

[TAC film surface treatment method]
A TAC film with a hard coat (film thickness of 80 μm) manufactured by Nippon Paper Industries Co., Ltd. was immersed in a 5% by weight aqueous potassium hydroxide (KOH) solution heated to 40 ° C. for 3 minutes for alkali treatment, then washed with water, The mixture was neutralized by immersing in a 5% by mass sulfuric acid (H ₂ SO ₄ ) aqueous solution (liquid temperature: 23 ° C.) for 30 seconds, washed with water and dried.
[Water contact angle]
Using an automatic contact angle meter CA-Z type manufactured by Kyowa Interface Science Co., Ltd., the contact angle when 3 microliters of pure water was dropped was measured.
Moreover, the water contact angle of the hard coat surface of the TAC film used in the examples was also measured by this method.

[Oil pen wiping off]
The ink applied to the surface of the cured coating using a Pentel oil pen was wiped off using Asahi Kasei Bencot M-3, and the ease of removal was visually determined. The ink was completely wiped off, and the others were marked with x.

[Fingerprint wiping properties]
Fingerprints were attached to the surface of the cured coating, wiped with Bencot M-3 manufactured by Asahi Kasei Co., Ltd., and the ease of removal was visually determined. The fingerprint was completely wiped off, and the others were marked with x.

[Adhesion]
Cut 100 points in a grid pattern at 1 mm intervals on the cured film on the substrate, and strongly attach cello tape (Nichiban Co., Ltd., 24 mm width) to the cured film, then peel off the cello tape rapidly to remove the cured film. The presence or absence was confirmed visually. The case where there was no peeling was marked with ◯, and the case where there was peeling was marked with ×.

[Reflectance]
Using a spectrophotometer UV3100PC manufactured by Shimadzu Corporation, light having a wavelength of 550 nm was incident on the cured film at an incident angle of 5 degrees, and the reflectance was measured.

[Abrasion resistance]
The cured coating, steel wool (Nippon Steel Wool Co., # 0000) by ^{using, 200g / cm 2, 600g /} cm 2 at 10 rubbed back and forth, was determined visually how scratch the cured coating surface.
Judgment criteria are as follows.
A: No scratches-10, B: Scratches 11-20, C: Scratches 21-30, D: Scratches 30-books, E: Peeling

[Refractive index]
The refractive index of light having a wavelength of 633 nm was measured using Ellipsometer DVA-36L manufactured by Mizoji Optical Co., Ltd.

Table 2 and as shown in Table 3, in Examples 1 to 10, at a curing temperature of 60 ° C., excellent properties and more B A, at 600 g / cm ² in scratch resistance 200 g / cm ^2, the water contact Excellent characteristics with an angle of 100 degrees or more were shown.
And the storage stability of the coating liquid (Q1-Q10) was also favorable, and was stable after storage at a temperature of 23 ° C. for 6 months.
Furthermore, in Examples 1-10, the characteristic of the low refractive index below 1.360 and the low reflectance was shown.
On the other hand, Comparative Examples 1 to 3 having only the amine compound (B) or the amine compound (C), or having no amine compound, have a scratch resistance of 600 g / cm ² at a curing temperature of 60 ° C. The following was insufficient.

  Moreover, as Table 2 and Table 3 showed, Examples 1-10 were excellent in the antifouling property called fingerprint wiping property and oil-based pen wiping property, and were high in adhesiveness with a base material.

The coating solution for forming a water-repellent film of the present invention is excellent in storage stability, can be sufficiently cured by a low-temperature heat treatment at a temperature of 20 to 70 ° C., and can provide a film having a low refractive index and excellent scratch resistance. Therefore, it can be suitably used particularly for an antireflection substrate, and in particular, can be suitably used for an antireflection film for a display element.

The entire contents of the specification, claims, and abstract of Japanese Patent Application No. 2007-132683 filed on May 18, 2007 are incorporated herein as the disclosure of the specification of the present invention. Is.

Claims (11)

  A polysiloxane (A) having a silicon atom to which a fluorine-containing organic group is bonded, a linear aliphatic amine compound (B) having 20 or less carbon atoms, and a total carbon number of 20 or less and in its structure And an amine compound (C) having a cyclic group having 10 or less carbon atoms, and a coating solution for forming a low refractive index film.   The coating liquid according to claim 1, wherein the polysiloxane (A), the aliphatic amine compound (B), and the amine compound (C) are dissolved in the organic solvent (D).   The coating liquid according to claim 1 or 2, wherein the polysiloxane (A) has 5 to 40 mol% of silicon atoms bonded with fluorine-containing organic groups with respect to all the silicon atoms.   The coating liquid according to claim 1, wherein the aliphatic amine compound (B) is a primary amine. The coating liquid in any one of Claims 1-4 by which an amine compound (C) is represented by following formula (1).

(In the formula, R ₁ represents a cyclic group having 3 to 10 carbon atoms, and R ₂ represents a single bond or an alkylene group having 1 to 17 carbon atoms.)   The coating liquid according to any one of claims 2 to 5, wherein the organic solvent (D) comprises at least one selected from the group consisting of alcohols having 1 to 6 carbon atoms and glycol ethers having 3 to 10 carbon atoms.   The total amount of silicon atoms contained in the polysiloxane (A) is 0.1 to 15% by mass in terms of silicon dioxide, and both the linear amine compound (B) and the amine compound (C) are polysiloxane ( The coating solution according to any one of claims 1 to 6, which is contained in an amount of 0.01 to 0.2 mol per mol of the total amount of silicon atoms in A). Furthermore, the coating liquid in any one of Claims 1-7 in which the silicon compound (E) represented by Formula (2) contains.

(In the formula, R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a saturated hydrocarbon group having 1 to 5 carbon atoms, and n represents an integer of 2 or more.)   A low-refractive-index film obtained by heating and curing the coating solution according to claim 1.   An antireflection material, wherein the low refractive index coating according to claim 9 is formed on the surface of a substrate having a higher refractive index than the coating.   A solution of alkoxysilane containing 5 to 40 mol% of alkoxysilane having a silicon atom bonded to a fluorine-containing organic group and having a concentration of 4 to 15% by mass in an organic solvent when all the silicon atoms are converted to silicon dioxide. , A step of polycondensation in the presence of 0.2 to 2 mol of succinic acid with respect to 1 mol of all alkoxide groups of the alkoxysilane to obtain a solution of polysiloxane (A), and the resulting polysiloxane (A) A linear alkylamine compound (B) having 20 or less carbon atoms, an amine compound (C) having a total carbon number of 20 or less and having a cyclic group having 10 or less carbon atoms in its structure, And a step of mixing a mixed solution of an organic solvent (D), and a method for producing a coating solution for forming a low refractive index film.