JP2007016096A - Curable composition, composition for coating, coating material, antifouling coating material, cured product thereof and antifouling method of base material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a curable composition having excellent spray coatability, a coating material and an antifouling method of an underwater structure. <P>SOLUTION: The curable composition contains (A) an organopolysiloxane having 500-25,000 number average molecular weight, and both molecular terminals of condensation-reactive functional groups, and (B) silica. The component (B) (i) is hydrophobic silica alone, or (ii) contains the hydrophobic silica. The composition preferably contains a hydrolyzable group of an organosilane or a partially hydrolyzed product thereof besides the components (A) and (B). The thickness of the film can be thickened, the coating process can be shortened, the amount of a solvent in the coating material can be reduced, the composition can complies with the PRTR regulation, and the composition exhibits good antifouling properties for a long period when used as the antifouling coating material. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a curable composition, a coating composition, a paint, an antifouling paint, a cured product thereof, and a substrate antifouling method. More specifically, the present invention is, for example, excellent in spray coating properties, can be thickened by a single coating, can shorten the coating period, and can obtain a coating film having a uniform thickness by the coating. The resulting coating film is excellent in coating film strength, coating film hardness, rubber physical properties, etc., exhibits excellent antifouling performance for a long period of time, and further has excellent storage stability before coating, The present invention relates to a coating composition, a paint, an antifouling paint, a cured product thereof, and an antifouling method for a substrate such as an underwater structure or a ship outer plate.

  Conventionally, in the production of a curable silicone composition, whether it is a one-component type or a two-component type, in order to sufficiently exhibit various properties after curing, such as surface smoothness and rubber strength, hydrophilic silica, or Hydrophobic silica surface-treated with hexamethyldisilazane or the like is blended.

  However, hydrophilic silica has poor affinity with silicone oil, and aggregates of fillers such as silica are produced in the curable silicone composition, and rubber having excellent characteristics even when such a composition is cured. Cannot be obtained. In addition, the hydrophobic silica has a good affinity with silicone oil, does not cause much aggregation in the composition, silica is relatively well dispersed, has a good thixotropy, and is suitable for vertical surfaces. Can be expected to be thickened by a single coating. However, this composition has a high viscosity and poor spray coating properties, and when diluted with a solvent, the thixotropy is suddenly lost, and the coating film sags or the smoothness of the coating film decreases. There is.

For example, (1): JP-A-10-316933 discloses (a) number average molecular weight of 20,000 to 10
A coating composition containing, as a main component, 10,000 room temperature curable silicone rubbers, (b) a room temperature curable silicone rubber having a number average molecular weight of 500 to 20,000, and (c) silicone oil,
Further, a coating composition containing hydrophobic fumed silica (d) is also shown. In this way, with a coating composition in which hydrophobic fumed silica is blended with two types of silicone rubbers having different molecular weights, it is possible to increase the film thickness by only one coating, but the storage stability of the coating is lacking and preparation is possible. Agar-like agglomeration is thought to be caused by secondary aggregation of silica during storage, so spray coating properties during painting are poor, and the coating surface is non-uniform during coating formation (thickness, color tone, etc. are uneven and smeared) There is a problem that a good coating film such as film thickness and rubber strength cannot be formed.

  By the way, underwater structures, fishing nets, etc. are used for a long time in water, especially in seawater.There are a lot of marine organisms such as hydro-insects, bugs, Aosa, Aonori, Serpura, oysters in contact with seawater. If attached or propagated, the original functions of underwater structures and fishing nets may be impaired. Among them, underwater structures such as water supply and drainage outlets of thermal power and nuclear power plants are constructed and fixed at predetermined positions in the sea, and aquaculture nets and stationary nets are left in the seawater for a long time. Breeding is remarkable, and frequent replacement, removal and cleaning must be performed, resulting in a large economic loss.

In order to solve such problems, antifouling paints are widely applied to the surface of underwater structures, fishing nets, seawater equipment, etc. for the purpose of preventing adhesion of marine organisms.
For example, (2): Japanese Examined Patent Publication No. 63-2959 discloses a non-toxic antifouling paint composition obtained by mixing a chemical reaction curable silicone rubber, a petrolatum or liquid paraffin mixture, and a low viscosity silicone oil. In this publication, it is described that if this composition is applied to the wetted part of an underwater structure, the growth of marine organisms can be prevented over a long period of time. However, with this non-toxic antifouling paint composition, it is difficult to obtain a sufficiently thick film just by applying it once, and the obtained coating film is inferior in strength and hardness and easily damaged. is there.

  (3): In Japanese Examined Patent Publication No. 60-3433, the applicant of the present application previously mixed an oligomer-like room-temperature-curing silicone rubber with paraffin or petrolactam, which is a petroleum direct distillation low critical surface tension substance. Although it is disclosed a coating for preventing marine organism adhesion diluted with an organic solvent, it has excellent long-term antifouling properties, but it is difficult to obtain a sufficient thick film only by applying it once. There was room for improvement in terms of conversion.

Further, the applicants previously proposed (4): Japanese Patent No. 2522854 discloses (A) an organopolysiloxane in which both ends of a molecular chain are blocked with silanol groups or hydrolyzable groups, and (B) Formula “R ¹ _a SiX _4-a (wherein R ¹ represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, X represents a hydrolyzable group, and a represents 0 or 1) And (C) in one molecule: ≡SiR ² OSiR ³ _b Y _3-b (wherein R ² is unsubstituted or substituted divalent carbonization) represents a divalent hydrocarbon group containing a hydrogen group or an ether bond, R ³ is an unsubstituted or substituted monovalent hydrocarbon group, Y is a hydrolyzable group, b is 0, 1 or 2. Here, R ^{When 2} is a divalent hydrocarbon group containing an ether bond, the carbon atom of the hydrocarbon group is directly bonded. A curable organopolysiloxane composition comprising at least one group represented by the formula (excluding an organopolysiloxane in which two or more trimethylsiloxy groups are bonded to Si atoms) and a cured product thereof. Further, the publication describes that as a filler, fine powdered silica, fumed silica, precipitated silica, etc., and those whose surfaces are hydrophobized with silane or the like may be blended. In addition, the publication describes that the cured product has no fear of environmental pollution and has a long-lasting antifouling effect, however, the curable organopolysiloxane composition described in the publication. However, there is room for improvement in terms of thickening, strength, hardness and the like of the coating film, and there are cases where the film is easily damaged, and there is room for further improvement in these respects.

In addition, in (5): JP-A-2001-139816, the applicants of the present application include (A) an organopolysiloxane having a condensation-reactive functional group at both ends of the molecule, and (B) hydrophobic silica. A curable composition in which the hydrophobic silica (B) is heat-treated with the organopolysiloxane (A), and the organopolysiloxane (A) is represented by the formula [α _{]: W 3-a (R} 1 a) Si (R 2) O- (Si (R 2) O) n -Si (R 1 a
) W _3-a (W in formula [α] represents a hydroxyl group or a hydrolyzable group, and R ¹ and R are C 1-12.
A monovalent hydrocarbon group, n represents an integer of 5 or more, and a represents 0, 1 or 2. The composition suitable for antifouling paints is proposed. By coating this curable composition, a coating film having a uniform film thickness and excellent long-term antifouling performance can be obtained. In particular, a fine solvent content type having a low content of xylene or the like as a solvent contained in the composition (eg: Solvent content is 1-10% by volume in the composition
In the case of a curable composition of about a degree, pinholes and craters are generated in the coating film, and the antifouling property may be lowered, and there is room for further improvement in these respects.

Further, in (6): Japanese Patent Application Laid-Open No. 2001-181509, the applicants of the present application (A) condensed at both ends of the molecule as in the case of the curable composition described in Japanese Patent Application Laid-Open No. 2001-139816 (5). A curable composition containing an organopolysiloxane having a reactive functional group and (B) hydrophobic silica and further containing hydrophilic silica has been proposed. As in the case of the curable composition disclosed in Japanese Utility Model Laid-Open No. 2001-139816 (5), in particular, in the case of a curable composition having a small solvent content type such as xylene as a solvent contained in the composition, the coating composition is applied. Pinholes and craters are generated in the film, and the antifouling property may be lowered, and there is room for further improvement in these respects.
JP 10-316933 A Japanese Examined Patent Publication No. 63-2959 Japanese Patent Publication No. 60-3433 Japanese Patent No. 2522854 JP 2001-139816 A JP 2001-181509 A

  The present invention is intended to solve the problems associated with the prior art as described above, and can reduce the solvent content contained in the paint, comply with the PRTR regulations, and can be thickened with a single coating. The object of the present invention is to provide a curable composition that can be shortened and the coating process can be shortened, and that the resulting cured coating film is excellent in long-term antifouling properties and the like.

  In addition, the present invention, when used as a coating material, particularly a paint, is excellent in paintability and the like (ie excellent in low solvent properties) even if the solvent content is reduced, can conform to PRTR regulations, and is excellent in spray paintability. The coating film can be made thicker by one-time coating and the coating period can be shortened. Furthermore, there is no pinhole, crater, etc. in the coating film obtained by applying the coating material with low solvent content, and the coating film surface is uniform. In addition, the obtained coating film is excellent in coating film strength and coating film hardness, and when used as an antifouling paint, excellent antifouling performance is exhibited for a long period of time. Furthermore, the object of the present invention is to provide a curable composition excellent in storage stability during storage before coating, in particular, a coating composition, a curable coating composition, and an antifouling coating composition.

  In addition, the present invention provides electrical parts, building materials, crafts, clothing industrial products, and medical products that are excellent in coating film strength, coating film hardness, surface smoothness, etc. when used as a coating material, particularly a paint as described above. And providing an antifouling coating film that exhibits excellent antifouling performance for a long period of time when used as an antifouling paint, or an underwater structure coated with the coating film, a ship skin, etc. It is an object.

  It is an object of the present invention to provide a method for producing a curable composition, a coating composition, and a curable (antifouling) coating composition so that a thick film having the above characteristics can be obtained by a single coating. It is said.

  Furthermore, the present invention is capable of forming a coating film having excellent properties as described above on the surface of various substrates such as the surface of an underwater structure, which is safe for an operator and can be efficiently formed without fear of environmental pollution. It is an object of the present invention to provide a method for forming a coating film on the surface of an electrical component or the like and a method for preventing the surface of a substrate such as a ship outer plate, an underwater structure, or a fishing net.

The curable composition according to the present invention is
(A) an organopolysiloxane having a number average molecular weight Mn (polystyrene conversion) measured by GPC of 500 to 25000 and both ends of the molecule being condensation-reactive functional groups;
(B) contains silica.

In the present invention, the silica (B) is
(i) hydrophobic silica, or
(ii) Hydrophobic silica and hydrophilic silica are desirable.

  The organopolysiloxane (A) in the present invention has the following formula [α]:

(Wherein, W represents a hydroxyl group or a hydrolyzable group, R ¹ and R each independently represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms, and a plurality of R ¹ , R may be the same or different from each other, n represents an integer of 5 or more, and a represents 0, 1 or 2.

In the present invention, when W in the formula [α] is a hydroxyl group and a is 2, in addition to the component (A) and the component (B),
(C) Formula [I]: in R ¹ _a SiX _4-a (wherein [I], R ¹ represents a monovalent hydrocarbon radical unsubstituted or substituted C1-8, X is a hydrolyzable group And a represents 0 or 1.)
It is desirable to contain the organosilane shown by these, or its partial hydrolyzate.

In the present invention, the hydrophilic silica is preferably heat-treated at a temperature of 100 ° C. or higher with the component (A).
In this invention, it is desirable to contain the said component (B) in the quantity of 1-100 weight part with respect to 100 weight part of said components (A).

Moreover, it is desirable to contain the said component (C) in the quantity of 1-20 weight part with respect to 100 weight part of said component (A).
In the present invention, the weight ratio of the hydrophobic silica (A) and the hydrophilic silica (B) ((A) / (B)) = 1.
It is desirable to contain at / 99-99 / 1.

In the present invention, the silicone oil (D) is preferably contained in an amount of 0.1 to 200 parts by weight with respect to 100 parts by weight of the component (A).
The silicone oil (D) preferably has a viscosity of 20 to 120 cs.

In the present invention, it is preferable that the solvent (E) further contains butyl acetate and / or ethylcyclohexane, and further both.
In this invention, it is preferable that the non volatile matter in a curable composition is 90% or more.

The curable composition of the present invention preferably further contains a catalyst, an antifouling agent and / or a colorant.
In the method for producing a curable composition according to the present invention, when producing the curable composition, the component (A) and at least the hydrophilic silica of the component (B) are heated to a temperature of 100 ° C. or higher. It is characterized by including the process of heat-processing by.

The coating composition according to the present invention comprises any one of the curable compositions described above.
In the present invention, the coating composition is preferably used as a paint or an antifouling paint.

The cured product according to the present invention is obtained by curing any of the curable compositions described above.
The coating film and antifouling coating film according to the present invention are formed by applying and curing the curable composition described above. The base material with a coating film according to the present invention is characterized in that the surface of the base material is coated with a coating film obtained by curing the curable composition according to any one of the above, Examples include electrical parts, electronic products, building materials, craft products, clothing industry products, medical products, and the like.

  In the method for forming a coating film on the surface of a substrate according to the present invention, the surface of the substrate such as the electrical component is coated or impregnated with a coating material comprising any of the curable compositions described above, and then The coating material is cured to form a coating film.

  The antifouling substrate according to the present invention is characterized in that the surface of the substrate that comes into contact with seawater or fresh water is coated with a coating film obtained by curing the curable composition described above. And as said base material, an underwater structure, a ship outer plate, a fishing net, and fishing gear are preferable.

  The antifouling method for a substrate according to the present invention comprises applying or impregnating an antifouling paint comprising any one of the curable compositions described above onto the surface of a substrate such as the underwater structure, and then the antifouling paint. Is cured to form an antifouling coating film.

  According to the present invention, the content of the solvent contained in the paint can be reduced, the PRTR regulations can be satisfied, the film thickness can be increased by a single coating, and the coating process can be shortened. The obtained cured coating film provides a curable composition having excellent long-term antifouling properties.

  In addition, according to the present invention, particularly when used as a coating composition or paint, even if the solvent content is reduced, the coating property is excellent (that is, the low solvent property is excellent), the PRTR regulation is satisfied, and the spray coating property is achieved. The film can be made thicker by a single coating and the coating period can be shortened, and the coating film obtained by coating the coating material with a low solvent content is free from pinholes, craters, etc. A good coating film with excellent uniformity is obtained, and the obtained coating film is also excellent in coating film strength and coating film hardness, and exhibits excellent antifouling performance for a long time when used as an antifouling paint. Further, a curable composition having excellent storage stability is provided before coating.

  Such a curable composition is suitably used as a coating composition, particularly as a curable coating composition or an antifouling coating composition. The cured product according to the present invention, particularly the cured coating product, is excellent in a good balance of rubber properties such as surface gloss, rubber hardness, and tensile strength. The underwater structure or ship outer plate coated with has properties such as long-term antifouling properties.

  According to the method for producing a curable composition according to the present invention, a desired thick film coating can be performed on the surface of a substrate standing upright by a single coating, and the coating material and paint, particularly high coating efficiency. A curable composition such as an antifouling paint can be produced. According to the antifouling method for a substrate surface according to the present invention, it is possible to reduce the solvent, and a coating film having excellent characteristics as described above can be safely applied to the surface of various substrates such as the surface of an underwater structure. In addition, a desired coating can be efficiently formed without fear of environmental pollution.

Hereinafter, the curable composition, the coating composition, the paint, the antifouling paint, the cured product thereof, and the antifouling method of the substrate according to the present invention will be specifically described.
<Curable composition>
The curable composition according to the present invention has (A) a specific number average molecular weight Mn (polystyrene equivalent value, the same applies hereinafter), and both ends of the molecule (chain molecule or molecular main chain) are condensation-reactive groups. The organopolysiloxane which is a functional group and (B) silica are contained.

As this silica (B), (B) (i) hydrophobic silica is contained, and hydrophilic silica is not contained.
The (A) organopolysiloxane having a specific number average molecular weight Mn and (B) (ii) “hydrophobic silica and hydrophilic silica” are contained.

Hereinafter, the organopolysiloxane (A) will be described first.
<Organopolysiloxane (A)>
As the above-mentioned organopolysiloxane (A), a polymer which is a main component of an organosilicone as described in Japanese Patent No. 2522854 (corresponding publication: JP-A-4-106156), particularly preferably a liquid polymer Such an organopolysiloxane (A) is represented by the following formula [α]:

(In the formula [α], W represents a hydroxyl group (—OH) or a hydrolyzable group, R ¹ and R each independently represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms, A plurality of R ¹ and R may be the same or different from each other, n represents an integer of 5 or more, and a represents 0, 1 or 2.

In this formula [α], when a = 0, 1, W is a hydrolyzable group, and when a = 2, W is preferably a hydroxyl group (—OH). In the present invention, when W in the formula [α] is a hydroxyl group and a is 2, in addition to the component (A) and the component (B) described above, (C) Formula [I]: R ¹ _a SiX _4-a (In Formula [I], R ¹ represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms; It represents a decomposable group, and a represents 0 or 1. It is preferable that an organosilane represented by the above or a partial hydrolyzate thereof is contained.

  Hereinafter, the organopolysiloxane (A) represented by the formula [α] will be described first. When W in the formula [α] is a hydrolyzable group, examples of such hydrolyzable group include an alkoxy group, an acyloxy group, an alkenyloxy group, an iminoxy group, an amino group, an amide group, an aminooxy group. Group etc. are mentioned, An alkoxy group is preferable.

  As the alkoxy group, those having 1 to 10 carbon atoms are desirable, and one or more oxygen atoms may be interposed between carbon atoms. For example, methoxy group, ethoxy group, propoxy group, butoxy group, A methoxyethoxy group, an ethoxyethoxy group, etc. are mentioned. The acyloxy group is preferably an aliphatic or aromatic group represented by the formula: RCOO— (wherein R is an alkyl group having 1 to 10 carbon atoms, an aromatic group having 6 to 12 carbon atoms), for example, , Acetoxy group, propionoxy group, butyroxy group, benzoyloxy group and the like.

The alkenyloxy group preferably has about 3 to 10 carbon atoms, and examples thereof include an isopropenyloxy group, an isobutenyloxy group, and a 1-ethyl-2-methylvinyloxy group. The iminoxy group (= N-OH, oxyimino group, ketoxime group) is preferably one having about 3 to 10 carbon atoms, for example, a ketoxime group, a dimethyl ketoxime group, a methyl ethyl ketoxime group, a diethyl ketoxime group, A cyclopentanoxime group, a cyclohexanoxime group, etc. are mentioned.

  The amino group is preferably one having 1 to 10 carbon atoms, for example, N-methylamino group, N-ethylamino group, N-propylamino group, N-butylamino group, N, N-dimethylamino group, N , N-diethylamino group, cyclohexylamino group and the like. The amide group preferably has 2 to 10 carbon atoms, and examples thereof include an N-methylacetamide group, an N-ethylacetamide group, and an N-methylbenzamide group.

The aminooxy group preferably has 2 to 10 carbon atoms in total, and examples thereof include an N, N-dimethylaminooxy group and an N, N-diethylaminooxy group. R ¹ and R each independently represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms, more preferably 1 to 10 carbon atoms, and particularly preferably 1 to 8 carbon atoms. Examples of the hydrogen group include an alkyl group, an alkenyl group, an aryl group, a cycloalkyl group, an aralkyl group, and the like.

  The alkyl group may be any type of linear, branched or alicyclic alkyl group, and the linear or branched alkyl group having 1 to 10, preferably about 1 to 8 carbon atoms. A cycloalkyl group having 3 to 6 carbon atoms is preferred. Examples of such linear or branched alkyl groups include alkyl groups such as methyl group, ethyl group, propyl group, butyl group, 2-ethylbutyl group and octyl group, particularly preferably methyl group. Examples of the cyclic alkyl group include a cyclohexyl group and a cyclopentyl group.

  The alkenyl group preferably has 2 to 10 carbon atoms, preferably about 2 to 8 carbon atoms, and examples thereof include a vinyl group, a hexenyl group, and an allyl group. The aryl group preferably has 6 to 15 carbon atoms, preferably about 6 to 12 carbon atoms, and examples thereof include a phenyl group, a tolyl group, a xylyl group, a naphthyl group, a diphenyl group, and the like, and a phenyl group is particularly preferable.

As a cycloalkyl group, a C3-C8 thing is desirable, for example, a cyclohexyl group etc. are mentioned. The aralkyl group preferably has a total carbon number of 7 to 10, preferably about 7 to 8, and examples thereof include a benzyl group and a 2-phenylethyl group. Some or all of the hydrogen atoms bonded to the carbon atoms in these groups R ¹ may be substituted with halogen atoms such as F, Cl, Br, and I, cyano groups, and the like. Examples thereof include a chloromethyl group, a 3,3,3-trifluoropropyl group, and a 2-cyanoethyl group.

R is preferably an unsubstituted monovalent hydrocarbon group, particularly preferably a methyl group or a phenyl group. In addition, in the organopolysiloxane (A) represented by the formula [α], when a plurality of R ¹ and a plurality of R are present, the plurality of R ¹ and the plurality of R Alternatively, R ¹ and R may be the same as or different from each other.

In the present invention, the component (A) is an organopolysiloxane (organopolysiloxane [α]) represented by the above formula [α], and any one or two of W, R ¹ , R, and n Those different in one or more may be used alone or in combination of two or more.

The number average molecular weight Mn (polystyrene equivalent value) measured by GPC (column: xylene divinylbenzene gel column) of such an organopolysiloxane (A) is usually 500 to 25000, preferably 1,000 to 20,000, particularly Preferably 2,000-13,000
0. In the present invention, since the organopolysiloxane (A) having such a number average molecular weight Mn is used, the resulting curable composition and coating composition have a high solid type (eg, solid content) with a low solvent content. It can be used as a composition with a content of 90 to 99% by volume, and was established in the PRTR method {1999 (Heisei 11)] Legal "} benefits, paintability, excellent sagging prevention when the resulting composition is diluted with a solvent, excellent long-term storage, smooth coating with a thick film with few coatings Film formation is possible, and the film has excellent pinholes and craters.

The viscosity at 25 ° C. of such an organopolysiloxane (A) varies depending on the use of the curable composition to be used and is not generally determined. However, the coating properties of the resulting composition, and when the resulting composition is diluted with a solvent In view of sagging prevention, etc., usually 25 cS (cSt) ~
1,500,000 cS (1.5 million cS), preferably 25 to 500,000 cS, more preferably 500 to 20,000 cS, particularly preferably 500 to 3,500 cS (both measured at 25 ° C.). Particularly low viscosity as component (A), for example 25-15
000 cS, preferably 500 to 15000 cS, more preferably 500 to 3500 cS, and more specifically 1000 cS (both 25 c
When a low-viscosity organopolysiloxane (A) is used, a high solid paint can be suitably formed. It should be noted that organopolysiloxanes with high viscosity (20,000 cSt) as shown in the examples of JP-A No. 2001-181509 are inferior in coating workability, particularly sprayability, when prepared into a high solid paint, Prone to pinholes and craters.
<Hydrophobic silica, hydrophilic silica (B)>
Silica includes hydrophilic silica (surface untreated silica) such as wet method silica (hydrated silica) and dry method silica (fumed silica, anhydrous silica); surface treatment such as hydrophobic wet silica and hydrophobic fumed silica Hydrophobic silica.

In the present invention, (i) hydrophobic silica is used alone or (ii) hydrophobic silica and hydrophilic silica are used in combination as the silica component (B). For this reason, when the obtained curable composition is used for a coating material (coating composition), a paint, particularly an antifouling paint, it has excellent stability during preparation, storage and storage, and has sufficient thixotropy, The film can be thickened by a single coating, and the resulting coating has excellent balance of rubber properties such as hardness, tensile strength, and elongation, and when used as an antifouling coating, it also has antifouling properties. Are better.

  In the present invention, those having the following characteristics may be used as they are as these silica components, but in a preferred embodiment thereof, as will be described in detail later, this silica component (B), that is, hydrophobic silica and hydrophilic silica. Of these, at least the hydrophilic silica is preferably heat treated together with a part or all of the component (A). Furthermore, both the hydrophilic silica and the hydrophobic silica are one of the components (A). It is desirable that the heat treatment is performed together with some or all.

Among these silicas (B), wet-process silica usually has an adsorbed water content (also referred to as water content) of about 4 to 8%, a bulk density of 200 to 300 g / L, and primary particles. The diameter is 10 to 30 mμ, and the specific surface area (BET surface area) may be 10 m ² / g or more,
Preferably 50 to 800 m ² / g, more preferably about 100 to 300 m ² / g.

Dry process silica (fumed silica) usually has a moisture content of 1.5% or less. This dry silica has a low initial moisture content of, for example, 0.3% or less, such as immediately after production. However, the moisture content gradually increases if left untreated, and after several months have passed since production. Then, for example, it becomes about 0.5 to 1.0%. In addition, the bulk density of such dry process silica varies depending on the type and is not unconditionally determined. For example, it is 50 to 100 g / L, the primary particle diameter is 8 to 20 mμ, and the specific surface area (BET surface area) is: 10m may be any ² / g or more, but is preferably 100 to 400 m ² / g, more preferably 180～300M ² / g approximately.

Hydrophobic fumed silica is a surface-treated dry process silica with an organosilicon compound such as methyltrichlorosilane, dimethyldichlorosilane, hexamethyldisilazane, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, etc. The water content is usually 0.3% or less, in many cases 0.1 to 0.2%, and the specific surface area may be 10 m ² / g or more, preferably 100 to 300 m ^2. / G, more preferably 120 to 230 m ² / g, the primary particle size is 5 to 50 mμ, and the bulk density is 50 to
100 g / L.

  In the hydrophobic fumed silica (heat treated hydrophobic fumed silica) heat-treated with the component (A), the moisture adsorbed on the surface of the hydrophobic silica is physically reduced and removed, and the moisture content is Usually, it is 0.2% or less, preferably 0.1% or less, particularly 0.05 to 0.1%, and other physical property values such as bulk density are the same as those of the hydrophobic silica.

  Such component (B) is usually used in an amount of 1 to 100 parts by weight, preferably 2 to 50 parts by weight, particularly preferably 5 to 30 parts by weight, based on 100 parts by weight of the component (A). It is desirable to be contained in the curable composition. When the silica component (B) is contained in such a quantity in the curable composition, the coating film strength and coating film hardness are excellent, the thixotropy is good, the viscosity is appropriate, and the coating is particularly good. Spray coating can be performed, and for example, even on a vertically erected substrate surface, it is preferable because the coating film can be thickened by a single coating.

  In addition, when the said component (B) is less than the said range, sufficient coating-film intensity | strength and coating-film hardness are not obtained, but desired thixotropy is not obtained, but desired thickening is carried out by one coating especially spray coating. If the amount of the component (B) exceeds the above range, the viscosity of the paint becomes excessively high, and it is necessary to dilute with a solvent such as thinner to an appropriate viscosity suitable for coating. Thickening by painting may not be possible.

  In the present invention, as the silica component (B), the above-described hydrophobic silica (I) is used alone, and the hydrophilic silica (B) may not be blended. Thus, as the component (B), when the hydrophilic silica (b) is not contained and only the hydrophobic silica (a) is contained, the physical properties of the paint tend to improve the thixotropy and sagging properties, Moreover, the physical properties of the cured coating film tend to be excellent in coating film strength, coating film hardness, and coating film smoothness.

Further, in the present invention, as the silica component (B), the hydrophobic silica (A) such as the hydrophobic fumed silica and the hydrophilic silica (B) such as surface untreated silica are used in a weight ratio ((A) / (B)) is 1 /
It is desirable to use these in an amount of 99 to 99/1, preferably 20/80 to 80/20, particularly preferably 30/70 to 70/30. When hydrophobic fumed silica (I) and hydrophilic silica (B) are used in combination in such a quantitative ratio, the resulting curable composition has excellent paint stability during preparation, storage and storage, and sufficient thixotropy. The coating film obtained by curing the composition tends to be excellent in coating film strength and coating film hardness.
<Organosilane or its partial hydrolyzate (C)>
In the present invention, when the component (A) is represented by the formula [α], W in the formula [α] is a hydroxyl group, and a is 2, such a component (A) In addition to the above component (B), (C) Formula [I]: R ¹ _a SiX _4-a (wherein R ¹ is an unsubstituted or substituted carbon atom having 1 to 8 carbon atoms) A monovalent hydrocarbon group similar to R, R ¹ and the like in the formula [α] is shown, X is a hydrolyzable group similar to W in the formula [α], and a is 0 or 1. It is preferable that the organosilane shown by (4) or its partial hydrolyzate is contained.

That is, in the present invention, the component (A) is a molecule (chain molecule, molecular chain).
In the case of using an organopolysiloxane having both ends of hydroxyl groups (—OH), specifically, a curable organopolysiloxane having both ends of molecular chains blocked with silanol groups (≡Si—OH), It is particularly preferable to use the component (A) in combination with the component (C) as a crosslinking agent / curing agent. Further, for example, when a curable organopolysiloxane having both molecular ends blocked with hydrolyzable groups is used as the component (A), it can be sufficiently cured even without the curing agent component (C). In such a case, it is more preferable to include the component (C).

  X is a hydrolyzable group similar to W in the formula [I]. Specific examples of the organosilane represented by the formula [I] or a (partial) hydrolyzate thereof include, for example, methyltrimethoxysilane, methyltri (methylethylketoxime) silane, methyltripropenyloxysilane, methyl Examples include triacetoxysilane and silane compounds obtained by substituting methyl groups of these silane compounds with vinyl groups, phenyl groups, trifluoropropyl groups, and the like, and partial hydrolysates thereof. In this case, the hydrolyzable group is preferably a ketoxime group.

These organosilanes or hydrolysates thereof (C) can be used in an amount of 1 to 60 parts by weight with respect to 100 parts by weight of the organopolysiloxane (A), but usually 1 to 20 parts by weight. It is desirable that it is contained in the curable composition of the present invention in an amount of preferably 2 to 10 parts by weight. When organosilane or its hydrolyzate (C) is contained in the composition in such an amount, the crosslinking reaction of component (A) proceeds well, and the resulting coating film has an appropriate hardness. There is a tendency to be excellent in economic efficiency.
<Silicone oil (D)>
The curable composition according to the present invention may contain a silicone oil (D). Examples of such a silicone oil (D) include non-reactive (non-condensable) silicone oils and curable compositions. It is not particularly limited as long as it is a silicone oil that bleeds out from the cured product, but it is preferably a component (D) different from the component (A), a silicone oil represented by the following formulas [II] and [IV], A silicone oil having a group represented by [III] is preferred.

Among these silicone oils (D), silicone oils [II] and [IV] do not exhibit reactivity or self-condensation with the component (A), and have an antifouling function on the coating surface (layer). The silicone oil [III] is considered to have a function of forming a layer (film), and the silicone oil [III] reacts with the component (A) as a coating film forming component to form a cured coating film. When it is immersed in water, it hydrolyzes over time, and the terminal group becomes a group “≡SiR ⁴ OH” having an alcoholic hydroxyl group, bleeds out to the surface of the coating film, and exhibits the effect of preventing the adhesion of marine organisms. It's thought to be.
(R ² ) ₃ SiO (SiR ³ ₂ O) _n Si (R ² ) ₃ ... [II]
(In the formula [II], a plurality of R ^{2 s} may be the same as or different from each other, and represent an alkyl group, aryl group, aralkyl group or fluoroalkyl group having 1 to 10 carbon atoms, and a plurality of R ^{3 s} are the same as each other. Or each R ³ represents an alkyl group having 1 to 10 carbon atoms, an aryl group, an aralkyl group or a fluoroalkyl group, and n represents a number from 0 to 150.)
_{^{≡SiR 4 OSiR 5 b Y 3-}} b ····· [III]
(In the formula [III], R ⁴ represents an unsubstituted or substituted divalent hydrocarbon group or a divalent hydrocarbon group containing an ether bond, R ⁵ represents an unsubstituted or substituted monovalent hydrocarbon group, and Y represents a hydrolyzed group. Degradable group, b is 0
, 1 or 2. )
_{^{R 6 x Si (R 7 -Z}} ) y O (4-xy) / 2 ····· [IV]
(In the formula [IV], R ⁶ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group or an aralkyl group, and R ⁷ has an ether group, an ester group or —NH— interposed therebetween. Represents a divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, and Z may be blocked with an amino group, a carboxyl group, an epoxy group, or an alkyl group or acyl group having 1 to 6 carbon atoms. 1 represents a monovalent polar group that is a polyethylene glycol or polypropylene glycol group, and x and y are 0.01 ≦ x <3.99, 0.02 ≦ y <4, and 0.02 ≦ x + y <, respectively. 4).

  Among the silicone oils (D), as the silicone oil [II], those described in JP-A-10-316933 can be used, and the number average molecular weight Mn is 180 to 10,000, preferably 1. , And a viscosity of 20 to 10,000 centistokes (cSt), preferably 30 to 1,000 centistokes (particularly preferably 50 to 150 centistokes (cSt (cs), measured at 25 ° C.). The same shall apply hereinafter).

Examples of such silicone oil [II] include dimethyl silicone oil in which all of R ² and R ³ are methyl groups, and phenyl methyl silicone in which a part of the methyl groups of these dimethyl silicone oils are substituted with phenyl groups. Examples of the oil include methylphenyl silicone oil. Specifically, as such methylphenyl silicone oil, for example, “KF-54, KF-56, KF-50” (manufactured by Shin-Etsu Chemical Co., Ltd.), “SH510, SH550” (manufactured by Toray Dow Corning Silicone) ), “TSF431, TSF433” (manufactured by Toshiba Silicone Co., Ltd.), etc.

As the silicone oil having the group represented by the above formula [III] (silicone oil [III]), those described in Japanese Patent No. 2522854 can be used, and the number average molecular weight is 250 to 10,000, Preferably, the viscosity is 1,000 to 5,000, and the viscosity is 20 to 30,000 centistokes (cSt), preferably 30 to 3000 centistokes, particularly preferably 50 to 150 centistokes (cSt, both measured at 25 ° C. The same shall apply hereinafter).
≡SiR ⁴ OSiR ⁵ _b Y _3-b・ ・ ・ ・ ・ [III]
(Wherein [III], R ⁴ represents a divalent hydrocarbon group containing a divalent hydrocarbon group or an ether bond unsubstituted or substituted, R ⁵ is an unsubstituted or substituted monovalent hydrocarbon group, Y hydrolysis Degradable group, b is 0
, 1 or 2. )
Specific examples of R ⁴ include unsubstituted or substituted divalent hydrocarbon groups such as a methylene group, an ethylene group, a propylene group, a butylene group, and a hexamethylene group; or “— (CH ₂ ) _p -O- (CH _{2) q} - "(wherein, p, q is a divalent hydrocarbon group containing an ether bond represented by each independently represent an integer of 1-6) and the like; and the like. .

R ⁵ represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms in the same manner as R ¹ in the formula [I] of the component (C). Y represents the same group as the hydrolyzable group X in the formula [I] of the component (C).

Specific examples of the silicone oil [III] having at least one group represented by the formula [III] include (CH ₃ ) ₃ as described in the above-mentioned Japanese Patent No. 2522854. SiO [(CH ₃ ) ₂ SiO] _m [R ⁷ R ⁸ SiO] _n (CH ₃ ) ₂ SiC ₃ H ₆ —OH, HO—C ₃ H ₆ — [(CH ₃ ) ₂ SiO] [(CH ₃ ) ₂ SiO] _m [R ⁷ R ⁸ SiO] _n — (CH ₃ ) ₂ Si—C ₃ H ₆ —OH, (CH ₃ ) ₃ SiO [(CH ₃ ) ₂ SiO] _m [R ⁷ R ⁸ SiO] _n Examples include those obtained by blocking the hydroxyl group of silicone oil represented by [(CH ₃ ) (C ₃ H ₆ —OH) SiO] _l [(CH ₃ ) ₂ SiCH ₃ ] with a hydrolyzable group. However, in the above formulas, R ⁷ ,
The R ^8, aryl groups such as phenyl and tolyl groups; a benzyl group, aralkyl groups such as β- phenylethyl group; a halogenated alkyl group such as trifluoropropyl group; As such, the R ^7, R ⁸ Among them, an unsubstituted or substituted monovalent hydrocarbon group, at least one of which is selected from a group other than a methyl group, can be mentioned. m, n, and l are all positive numbers.

In addition, from the viewpoint of storage stability of the resulting composition, as exemplified below, the above silicone oil is represented by the formula: “R ⁵ _b SiY _3-b ” (R ⁵ , Y, and b are represented by the formula [III] It may be the same as in the case of the above)). (CH ₃ ) ₃ SiO [(CH ₃ ) ₂ SiO] _{m
^{[R 7 R 8 SiO] n}} (CH 3) 2 SiC 3 H 6 -O-R 5 b SiY 3-b, HO-C 3 H 6 - [(CH 3) 2 SiO] [(CH 3) 2 SiO _{^{] m [R 7 R 8 SiO}} ] n - (CH 3) 2 Si-C 3 H 6 -O-R 5 b SiY 3-b, (CH 3) 3 SiO [(CH 3) 2 SiO] m [R such as _{^{7 R 8 SiO] n [(}} CH 3) (C 3 H 6 -O-R 5 b SiY 3-b) SiO] l [(CH 3) 2 SiCH 3].

As the silicone oil [IV], specifically, those described in JP-A-10-316933 can be used, and the number average molecular weight Mn is 250 to 30,000, preferably 1,000 to 20, And a viscosity of 20 to 30,000 centistokes, preferably 30 to 3,000 centistokes, particularly preferably 50 to 150 centistokes.
_{^{R 6 x Si (R 7 -Z}} ) y O (4-xy) / 2 ····· [IV]
(In the formula [IV], R ⁶ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group or an aralkyl group, and R ⁷ has an ether group, an ester group or —NH— interposed therebetween. Represents a divalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, and Z may be blocked with an amino group, a carboxyl group, an epoxy group, or an alkyl group or acyl group having 1 to 6 carbon atoms. 1 represents a monovalent polar group that is a polyethylene glycol or polypropylene glycol group, and x and y are 0.01 ≦ x <3.99, 0.02 ≦ y <4, and 0.02 ≦ x + y <, respectively. 4).

As such silicone oil [IV], preferably, in the above formula [IV], R ⁶ is a methyl group or a phenyl group, and R ⁷ is a methylene group, an ethylene group or a propylene group is desirable. . In addition, as Z, when the terminal is a polyethylene glycol or polypropylene glycol group which may be blocked with an alkyl group or acyl group having 6 or less carbon atoms, the number of oxyethylene and oxypropylene as a repeating unit is 10 to 60 preferable. Examples of the alkyl group for end-capping include a methyl group, an ethyl group, a propyl group, and a butyl group. Examples of the acyl group for end-capping include a ketoxime group, an acetyl group, and a propionyl group. .

  Specifically, as silicone oils in which the polar group Z is an amino group, “SF8417” (manufactured by Toray Dow Corning), “ISI4700, ISI4701” (manufactured by Toshiba Silicone), “FZ3712, AFL-40” (Japan) Unicar) and the like. Examples of the silicone oil in which the polar group Z is a carboxyl group include “XI42-411” (manufactured by Toshiba Silicone), “SF8418” (manufactured by Toray Dow Corning Silicone), “FXZ4707” (manufactured by Nihon Unicar), and the like. . Silicone oils whose polar groups are epoxy groups include “SF8411” (manufactured by Toray Dow Corning Silicone), “XI42-301” (manufactured by Toshiba Silicone), “L-93, T-29” (Nihon Unicar Company). Manufactured) and the like. Examples of the silicone oil in which the polar group Z is an alkyl group or an acyl group include “ISI4460, ISI4445, ISI4446” (manufactured by Toshiba Silicone), “SH3746, SH8400, SH3749, SH3700” (manufactured by Toray Dow Corning Silicone), “X -31-1234-99 "(manufactured by Shin-Etsu Silicone) and the like.

In the present invention, among these silicone oils (D), the viscosity (measurement condition: 25 ° C.) is preferably 20 to 120 cst, and more preferably 50 to 100 cst (A) organopolysiloxane These are more preferable in terms of compatibility, and the resulting coating film has excellent antifouling properties.

In the present invention, such silicone oil (D), preferably any one or two of silicone oil [II], silicone oil [III] and silicone oil [IV] is used.
It is desirable that the seeds or more are contained in an amount of 0.1 to 200 parts by weight, preferably 20 to 100 parts by weight in total with respect to 100 parts by weight of the component (A).

  When the amount of this silicone oil (D) is in the above range, for example, when used as an antifouling paint, there is a tendency to obtain a (antifouling) coating film excellent in both antifouling properties and coating film strength. If it is less, the antifouling property is lowered, and if it is more than the above range, the coating strength may be lowered.

[Production of curable composition]
Such a curable composition according to the present invention, in particular, a coating composition, a curable coating composition, and an antifouling coating composition are used in the case where hydrophobic silica and hydrophilic silica are used in combination as the component (B). In advance, part or all of the component (A) and at least the hydrophilic silica of the component (B), preferably both hydrophilic silica and hydrophobic silica,
Under normal pressure or reduced pressure, after heat treatment at 100 ° C. or higher and below the decomposition temperature of the blended components, preferably 100 to 300 ° C., more preferably about 140 ° C. to 200 ° C., usually about 30 minutes to 3 hours, In addition to the remaining component (A), (B), and component (C) used as necessary, the component (D) can be further blended as necessary.

  Further, when only the hydrophobic silica (I) of the hydrophobic silica and the hydrophilic silica is used alone as the component (B), such a curable composition according to the present invention, particularly a coating composition. Products, curable coating compositions and antifouling coating compositions are prepared in advance by subjecting part or all of component (A) and hydrophobic silica (I) as component (B) to the same conditions (pressure, temperature). , Time), and then the remainder (A), (C), (D), etc. added as necessary can be blended.

  In the present invention, conventionally known organosiloxane curing catalysts, antifouling agents, thixotropy imparting agents, plasticizers, inorganic dehydrating agents (stabilizers), anti-sagging / anti-settling agents (thickening agents), coloring pigments, Dyes, other film forming components, solvents (eg butyl acetate, ethylcyclohexane, xylene), bactericides, fungicides, anti-aging agents, antioxidants, antistatic agents, flame retardants, heat conduction improvers, adhesion A property-imparting agent or the like may be added at a predetermined ratio all at once or in an arbitrary order, stirred and mixed, and dissolved or dispersed in a solvent.

  When hydrophobic silica and hydrophilic silica are used in combination as component (B) as described above, at least hydrophilic silica, preferably both hydrophilic silica and hydrophobic silica, are used as component (A). When the heat treatment is performed, the components (A) and (B) in the resulting composition are excellent in affinity and there is no aggregation of the filler component such as the component (B). For example, the resulting coating composition, for example, The antifouling coating composition exhibits appropriate fluidity, thixotropy, etc., and can be applied to a vertical coating surface or the like with a small number of coatings such as a single coating of a desired sufficient thickness.

  In addition, when hydrophobic silica is used alone as the component (B), when the hydrophobic silica and the component (A) are heat-treated, a composition having the same physical properties as those described above, in particular, thick film, Coating compositions, antifouling paint compositions and the like having excellent performance of uniformity can be obtained.

In the case of stirring and mixing the above-described blending components, conventionally known mixing and stirring devices such as a loss mixer, a planetary mixer, and a universal Shinagawa stirrer are appropriately used. As the catalyst, for example, those described in Japanese Patent No. 2522854 can be preferably used. Specifically, for example, tin carboxylates such as tin naphthenate and tin oleate; dibutyltin diacetate, Tin compounds such as dibutyltin dioctoate, dibutyltin dilaurate, dibutyltin dioleate, dibutyltin oxide, dibutyltin dimethoxide, dibutylbis (triethoxysiloxy) tin; tetraisopropoxy titanium, tetra n-butoxy titanium, tetrakis (2-ethylhexoxy) In addition to titanate esters or titanium chelate compounds such as titanium, dipropoxybis (acetylacetonato) titanium, titanium isopropoxyoctyl glycol; etc., zinc naphthenate, zinc stearate, zinc-2-ethyl octoate, iron- 2 Organometallic compounds such as ethylhexoate, cobalt-2-ethylhexoate, manganese-2-ethylhexoate, cobalt naphthenate, alkoxyaluminum compound; 3-aminopropyltrimethoxysilane, N-β (amonoethyl ) Aminoalkyl group-substituted alkoxysilanes such as γ-amonopropyltrimethoxysilane; amine compounds such as hexylamine, dodecyldodecylamine phosphate, dimethylhydroxylamine, diethylhydroxylamine, and salts thereof; and benzyltriethylammonium acetate Quaternary ammonium salts; lower fatty acid salts of alkali metals such as potassium acetate, sodium acetate and lithium odorate; tetramethylguanidylpropyltrimethoxysilane, tetramethylguanidylpropylmethyldimethoxy Orchids, silanes or siloxanes containing tetramethylguanidylpropyltrimethoxysilane (trimethylsiloxy) guanidyl group such as a silane; and the like.

These catalysts are used in an amount of 10 parts by weight or less, preferably 5 parts by weight or less, and more preferably 1 part by weight or less based on 100 parts by weight of the component (A), and a preferred lower limit when using these catalysts. The value is 0.001 part by weight or more, particularly 0.01 part by weight or more.
<Optional component>
As described above, when the curable composition according to the present invention is used as, for example, a coating composition, particularly a paint composition or an antifouling paint composition, particularly a curable antifouling paint composition, the above components are used. In addition to (A), (B) and the component (C) used as necessary, an antifouling agent, a plasticizer, an inorganic dehydrating agent, a carboxylic acid metal salt, a sauce as described in detail below if necessary. Anti-settling / anti-settling agent (fading agent), pigments, other film forming components, other fillers, flame retardants, thixotropic agents, heat conduction improvers, solvents, antifungal agents, antibacterial agents, matting agents In addition, various components such as a fragrance may be contained.
<Anti-fouling agent>
The antifouling agent may be either inorganic or organic. As the inorganic antifouling agent, conventionally known antifouling agents can be used, and among these, copper and inorganic copper compounds are preferable.
Organic antifouling agent As organic antifouling agent, metal-pyrithiones represented by the following formula (vi) [wherein R ^{1 to} R ⁴ each independently represent hydrogen, an alkyl group, an alkoxy group, or a halogenated alkyl group. , M represents a metal such as Cu, Zn, Na, Mg, Ca, Ba, Pb, Fe, and Al, and n represents a valence]:

, Tetramethylthiuram disulfide, carbamate compounds (eg, zinc dimethyldithiocarbamate, manganese-2-ethylenebisdithiocarbamate), 2, 4, 5,
6-tetrachloroisophthalonitrile, N, N-dimethyldichlorophenylurea, 4,5-dichloro-2-n-octyl-3 (2H) isothiazoline, 2,4,6-trichlorophenylmaleimide, 2-methylthio-4- Examples thereof include t-butylamino-6-cyclopropyl striazine.

Among the above organic antifouling agents, copper pyrithione (in formula (vi), M = Cu), zinc pyrithione (in formula (vi), M = Zn), N, N-dimethyldichlorophenylurea, 2,4,6- Trichlorophenylmaleimide, 2-methylthio-4-t-butylamino-6-cyclopropylstriazine, 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one, 2,4,5,6- Tetrachloroisophthalonitrile is preferred.

  Among these organic antifouling agents, metal pyrithiones and / or 4,5-dichloro-2-n-octyl-4-isothizolin-3-one are preferable, and further, when used in combination, antifouling performance is excellent. It is particularly preferable to use copper pyrithione and / or 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one, and it is more preferable to use these in combination.

In the antifouling paint composition containing such an organic antifouling agent, for example, in addition to copper and / or an inorganic copper compound, the organic antifouling agent is usually 0.1 to 20% by weight, preferably 0.5%. It is desirable that it be contained in an amount of -10% by weight. Moreover, with respect to 100 weight part of solid content contained in a coating composition, this organic antifouling agent is 0.1-150 weight part normally as solid content, Preferably it is the quantity of 0.1-100 weight part. It is desirable that it be included.
<Plasticizer (chlorinated paraffin)>
Examples of the plasticizer include TCP (tricresyl phosphate), chlorinated paraffin, polyvinyl ethyl ether, and the like. These plasticizers can be used alone or in combination of two or more. These plasticizers contribute to the improvement of crack resistance of a coating film (also referred to as “antifouling coating film”) made of the resulting antifouling coating composition.
<Inorganic dehydrating agent>
The inorganic dehydrating agent also functions as a stabilizer and can further improve the storage stability of the antifouling coating composition. Examples of such an inorganic dehydrating agent include anhydrous gypsum (CaSO ₄ ) and synthetic zeolite-based adsorbents. (Trade name: molecular sieve, etc.), silicates and the like, and anhydrous gypsum and molecular sieve are preferably used. Such inorganic dehydrating agents can be used alone or in combination.

In the curable coating composition containing such an inorganic dehydrating agent, this inorganic dehydrating agent is usually 0.1 to 10% by weight, preferably 0.1 to 10% by weight, in the non-tin coating composition of the present invention. It may be contained in an amount of about 5% by weight.
<Carboxylic acid metal salt>
The curable coating composition according to the present invention may further contain a carboxylic acid metal salt.

As the carboxylic acid metal salt, those having a molecular weight of usually 50 to 1000, preferably 100 to 600 are used. As the carboxylic acid constituting such a carboxylic acid metal salt, a carboxylic acid having an alicyclic structure (eg, naphthenic acid), a carboxylic acid having an aromatic ring structure (eg, α- (2-carboxyphenoxy) stearic acid) , Rosin resin acid, fatty acid, and the like, and naphthenic acid, rosin resin acid, and fatty acid are preferable.
<Anti-sagging / Anti-settling agent (fading agent)>
Anti-sagging and anti-settling agents (fading agents) include organoclay Al, Ca, Zn stearate salts, lecithin salts, alkyl sulfonate salts, polyethylene wax, amide wax, hydrogenated castor oil wax system Polyamide wax and mixtures thereof, synthetic fine powder silica, oxidized polyethylene wax, and the like. Polyamide wax, synthetic fine powder silica, oxidized polyethylene wax, and organic clay are preferably used. Examples of such anti-sagging and anti-settling agents are those marketed under the trade names such as “DISPARON 305” and “DISPARON 4200-20” manufactured by Enomoto Kasei Co., Ltd. and “DISPARON A630-20X”. Is mentioned.

Such an anti-sagging / anti-settling agent is blended in the curable coating composition in an amount of 0.1 to 10% by weight, for example.
<Pigment>
As the pigment, various conventionally known organic and inorganic pigments can be used.

Examples of organic pigments include carbon black, phthalocyanine blue, and bitumen.
Examples of inorganic pigments are neutral and non-reactive such as titanium white, bengara, barite powder, silica, tankal, talc, chalk, iron oxide powder, etc .;
Examples thereof include zinc oxide (ZnO, zinc oxide), white lead, red lead, zinc dust, lead oxide powder, and the like (active pigments) that are basic and reactive with acidic substances in the paint.

Various colorants such as dyes may also be included. Such various pigments are blended in the curable composition, particularly in the curable coating composition, for example, in an amount of about 0.5 to 45% by weight in total.
<Other coating film forming components>
As the coating film forming component, a coating film forming component other than the above-described organopolysiloxane (A) may be contained within a range not contrary to the object of the present invention. As, for example, acrylic resin, acrylic silicone resin, unsaturated polyester resin, fluororesin, polybutene resin, urethane resin (rubber), polyamide resin, vinyl chloride copolymer resin, chlorinated rubber (resin), chlorinated olefin resin, Styrene / butadiene copolymer resin, ethylene-vinyl acetate copolymer resin, vinyl chloride resin, alkyd resin, coumarone resin, trialkylsilyl acrylate (co) polymer (silyl resin), difficult or water-insoluble resin such as petroleum resin (Hereinafter also referred to as difficult / water-insoluble resin).
<Other fillers, flame retardants, thixotropic agents, heat conduction improvers, adhesive components, etc.>
As fillers other than those mentioned above, diatomaceous earth, iron oxide, zinc oxide, titanium oxide, alumina and other metal oxides or surfaces thereof treated with a silane compound; calcium carbonate, magnesium carbonate, zinc carbonate, etc. In addition, asbestos, glass fiber, carbon black, quartz powder, aluminum hydroxide, gold powder, silver powder, surface-treated calcium carbonate, glass balloon, and the like. These fillers may be used alone or in combination of two or more.

Examples of the thixotropic property-imparting agent include polyethylene glycol, polypropylene glycol, and derivatives thereof. Examples of the flame retardant include antimony oxide and paraffin oxide. Examples of the heat conduction improver include boron nitride and aluminum oxide. Examples of the adhesive component include a substance containing one or more groups such as an alkoxysilyl group, an epoxy group, a hydrosilyl group, an acrylic group, and a hydroxysilyl group, or a mixture of these substances.
<Solvent (E)>
The curable composition such as the curable coating composition of the present invention may or may not contain a solvent. However, the low boiling point solvent, particularly the boiling point of the solvent is 100 ° C. or less, particularly 50 It is also preferable from the viewpoint of PRTR measures to contain as little as possible a low boiling point solvent of about -80 ° C or to keep it in a small amount. Further, when a solvent is used in the present invention, it is desirable to use one or a combination of two or more high boiling solvents having a boiling point of 100 ° C. or higher, preferably about 110 to 150 ° C.

In the present invention, the various components as described above can be used by dissolving or dispersing in a solvent, if necessary.
Examples of the solvent that can be used here include, for example, aliphatic (which may have an alicyclic structure), aromatic, ketone, ester, ether, alcohol, etc. Various solvents that can be blended are used.

  Examples of the aliphatic solvent (which may have an alicyclic structure) include ethylcyclohexane (boiling point 132 ° C.), methylcyclohexane (boiling point 100.9 ° C.), n-hexane (boiling point 68.7 ° C.), n-heptane (98.4 ° C), n-decane and the like aliphatic solvents which may have an alicyclic structure, among these aliphatic solvents having an alicyclic structure in terms of the above high boiling point, especially Ethylcyclohexane is preferred.

Examples of the aromatic solvent include xylene (boiling point: 138 to 144 ° C.), toluene (boiling point 110.6 ° C.), and the like.
Examples of the ketone solvent include MIBK (boiling point 115.9 ° C.), cyclohexanone (boiling point 155.7 ° C.), and the like.
Examples of ester solvents include butyl acetate (boiling point 126.1 ° C), isobutyl acetate (boiling point 110 to 119 ° C), and the like.
Examples of the ether solvent include propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate (PMAC), and the like.
Examples of the alcohol solvent include isopropyl alcohol.

These solvents are used alone or in combination of two or more.
In the present invention, it is preferable to use a combination of an aliphatic solvent which may have an alicyclic structure and an ester solvent, and in particular, ethylcyclohexane (boiling point 132) of the aliphatic solvent having the alicyclic structure. ° C) and an ester solvent butyl acetate (boiling point: 126.1 ° C) are preferably used in terms of PRTR regulations, coating film uniformity, and the like.

In particular, in the present invention, when the component (A) having the number average molecular weight Mn, silica (B), and ethylcyclohexane (I) and butyl acetate (B), which are the solvents, are used in combination, it is apparent in Table 2. Thus, when the obtained paint is applied immediately after the production of the paint, there is no occurrence of craters, excellent sagging properties (limit film thickness), excellent workability in coating, and a good coating state, Even when the same coating is applied after storage at 50 ° C for 3 months, the spray coating and sagging properties are excellent, the leveling property (coating flattening property) is excellent, the crater is not generated, and the coating state is good. In addition, the storage state of the paint tends to be good. In particular, butyl acetate (b) is 10 to 99% by weight, preferably 50 to 95% by weight in 100% by weight of the total of ethylcyclohexane (b) and butyl acetate (b) as the solvent. When the combination of (A) and (B) is used in an amount, the above-mentioned effect tends to be remarkable.

  Such a solvent can be used in any amount, but can be used in an amount of, for example, 0.1 to 9999 parts by weight, preferably 1 to 50 parts by weight with respect to 100 parts by weight of the component (A). However, consideration of the environment and securing of paintability, smooth coating film is obtained, balance with securing of excellent coating film performance such as few pinholes and craters in coating film, long-term storage stability etc. Considering the viewpoint more, it is particularly preferably used in an amount of 1 to 15 parts by weight relative to 100 parts by weight of the component (A).

Further, it is used in the curable composition of the present invention in an amount of 1 to 99% by weight, preferably 5 to 50% by weight, particularly preferably 5 to 10% by weight, for the same reason. The viscosity (25 ° C., B-type viscometer, No. 3 rotor) of a curable composition such as a curable coating composition diluted as necessary with such a solvent is coatability (sagging property), applied once In consideration of the film thickness obtained by the above, for example, it is about 0.01 to 100 poise / 25 ° C., preferably about 0.1 to 50 poise / 25 ° C. In other words, it is about 0.001 to 10 Pa · s, preferably about 0.01 to 5 Pa · s, and particularly preferably about 0.1 to 2 Pa · s.

  The curable composition of the present invention is used as a coating material (coating composition) for surface coating of various substrates such as electric parts, electronic parts, building materials, craft supplies, clothing industrial articles, medical supplies, seawater or It is suitably used as an antifouling paint for surface antifouling of substrates that come into contact with fresh water, for example, substrates such as underwater structures, ship skins, fishing nets, and fishing gear.

  In addition, it is also used as an anti-icing paint and a water repellent. Thus, the curable composition of the present invention has a wide range of industries such as electricity / electronics, building materials / crafts, clothing industry, medical care, agriculture / forestry / fishery industry, power generation, port / civil engineering construction, shipbuilding or ship repair, especially ship painting. Used in the field.

  In particular, when the curable composition is applied as a coating composition to a substrate surface such as an electrical component, electronic article, building material, craft article, clothing industrial article, or medical article, the composition has a low viscosity. The balance between high thixotropy is excellent, so thickening can be achieved with a single coating and coating workability is good. By coating and curing such a composition, for example, flame retardancy, rubber strength, surface A substrate with a coating film excellent in smoothness and the like is obtained.

  In particular, curable compositions as described above are used as paints, particularly antifouling paints (antifouling paint compositions), for example, underwater structures such as thermal and nuclear power plants, seawater use equipment (eg seawater) Pumps, etc.), megafloats, bay roads, submarine tunnels, harbor facilities, canals, waterways, etc. for various civil engineering works such as sludge diffusion prevention films, ships, especially ship skins, fishing materials (eg ropes, fishing nets, floats) , Buoys, etc.) on the surface of various molded products according to a conventional method once to multiple times and cured, it is excellent in antifouling property, and the antifouling agent component can be gradually released over a long period of time. However, an antifouling substrate such as an antifouling film-coated ship or an underwater structure having moderate flexibility and excellent crack resistance can be obtained. In such coating, conventionally known coating means such as brushes, rolls, sprays, dip coaters and the like are widely used.

  The antifouling coating film obtained by applying and curing the curable antifouling coating composition according to the present invention on the surface of various molded bodies (base materials) is a water tank such as Aosa, Barnacle, Aonori, Cell plastic, Oyster, Fusakomushi. It has excellent antifouling properties such as being able to prevent organisms from sticking for a long time. In particular, the curable antifouling paint composition is used for the surface of these base materials (materials) even when the material of the water supply / drainage port, mega float, ship, etc. of nuclear power plants is FRP, steel, wood, aluminum alloy, etc. Adheres well. The curable antifouling coating composition may be overcoated on the surface of an existing antifouling coating film.

  Also, for example, if the curable antifouling coating composition is applied and cured on the surface of an underwater structure, adhesion of marine organisms can be prevented, and the function of the structure can be maintained for a long period of time. For example, it is possible to prevent the mesh of the fishing net from being blocked and to reduce the risk of environmental pollution. The curable antifouling paint composition according to the present invention may be applied directly to a fishing net, or applied to the surface of a ship or an underwater structure or the like on which a base material such as a rust preventive agent or primer has been applied in advance. May be.

  Furthermore, the surface of a ship that has already been coated with a conventional antifouling paint or that has been coated with the curable antifouling paint composition of the present invention, particularly an FRP ship or an underwater structure, is used for repair. The curable antifouling coating composition of the present invention may be overcoated. Thus, although the thickness of the antifouling coating film formed on the surface of a ship, an underwater structure, etc. is not specifically limited, For example, it is about 30-150 micrometers / time.

The antifouling coating film according to the present invention obtained as described above, or the coating film on the surface of the water contact part of the ship / underwater structure, is formed from the curable antifouling coating composition as described above, and is an environmental pollution. It has excellent long-term antifouling properties against a wide range of ships and underwater structures.
[The invention's effect]
When the curable composition according to the present invention is used as a coating composition, particularly a paint, an antifouling paint composition, etc., it exhibits a good balance between low viscosity and high thixotropy, and there is no nozzle clogging or disturbance. Excellent paintability, can be thickened by a single coating, shortens the coating period, and the coating film surface uniformity (film thickness uniformity or surface smoothness) A cured product is obtained, and the obtained coating film is excellent in coating film strength (rubber strength) and coating film hardness. When used as an antifouling paint, the resulting coating film has excellent antifouling performance for a long period of time. In addition, it has excellent storage stability during storage before coating. Accordingly, a curable composition suitable as a coating composition, particularly as a curable coating composition or an antifouling coating composition is provided. The

In addition, according to the present invention, as described above, the coating film strength and coating film hardness are excellent, and various cured products such as coating films and coating cured products that exhibit excellent antifouling performance for a long period of time, Provided are an antifouling coating film, an underwater structure coated with the coating film and having these characteristics, a ship skin, and the like. Furthermore, according to the present invention, a coating film having excellent properties as described above can be efficiently formed on the surface of various substrates such as the surface of an underwater structure, safely for the operator, and without fear of environmental pollution. It is possible to provide a method for forming a coating film on the surface of a substrate such as an electronic component and a method for preventing soiling of a substrate such as an underwater structure.
[Example]
Hereinafter, although an example and a comparative example explain the present invention still more concretely, the present invention is not limited at all by the example and comparative example which concern. In addition, the composition value etc. which are described in the following synthetic examples, examples, and comparative examples are parts by weight.
[ Synthesis of Silicone Oil (D)]
[Synthesis Example 1]

  Following formula:

193 g of an organopolysiloxane containing an alcoholic hydroxyl group represented by the formula and 60 g of methyltri (methylethylketoxime) silane are mixed and reacted at room temperature, and the formula:

A silicone oil (D) containing a ketoxime-based organopolysiloxane represented by the formula {viscosity: 65 cSt / 25 ° C., number average molecular weight Mn: 3500} was obtained. This silicone oil contained unreacted raw material methyltri (methylethylketoxime) silane.
[Preparation of organopolysiloxane coating compositions (A) to (F) described in Table 1]
Both molecular ends are blocked with silanol groups, viscosity is 1,000 cst (1,000 cst), number average molecular weight Mn measured by GPC (in terms of polystyrene): 9,400 dimethylpolysiloxane in 50 parts by weight, 10 parts by weight of hydrophobic fumed silica surface-treated with methyldisilazane mixed and stirred for 2 hours at 150 ° C. (see * 2)
Similarly, the same hydrophobic silica described in Table 1 was mixed with 50 parts by weight of organopolysiloxane and stirred at room temperature (see * 3), and 10 parts by weight of hydrophilic silica described in Table 1 was added to organopolysiloxane. A mixture of 50 parts by weight of siloxane and stirred at 150 ° C. for 2 hours and heat-treated (see * 4) was blended in the blending amounts shown in Table 1, and sufficiently mixed and dispersed with a stirrer.

Furthermore, a crosslinking agent and a catalyst were added in the blending amounts shown in Table 1 and mixed uniformly to obtain a room temperature curable organopolysiloxane coating composition having a composition as shown in (A) to (F).
These property values and coating film properties are shown in Table 1.

In Table 1, * 1, 2, 3, 4 and test methods are as follows. Moreover, in the table | surface, various silica is the quantity (weight part) of the silica with respect to 100 weight part of organopolysiloxane (A).
* 1: Organopolysiloxane: manufactured by Shin-Etsu Chemical Co., Ltd., chemical formula: “HO (CH ₃ · CH ₃ · SiO) _m H” (viscosity at 25 ° C .: 1,000 cs, number average molecular weight measured by GPC (25 ° C.)) Mn (polystyrene conversion): 9,400).
* 2: Heat treated hydrophobic fumed silica: Silica obtained by mixing and stirring the hydrophobic fumed silica listed in Table 1 and the above organopolysiloxane by mixing and stirring at 150 ° C. for 2 hours, manufactured by Shin-Etsu Chemical Co., Ltd. The content is 0.05%, the bulk density is 50 g / L, the primary particle diameter is 10 mμ, and the specific surface area (BET surface area) is 180 m ² / g.
* 3: Room-temperature treated hydrophobic fumed silica: Silica obtained by mixing and stirring the hydrophobic fumed silica listed in Table 1 and the above organopolysiloxane at room temperature for 2 hours, manufactured by Shin-Etsu Chemical Co., Ltd., with a moisture content of 0.2% The bulk density is 50 g / L, the primary particle diameter is 10 mμ, and the specific surface area (BET surface area) is 180 m ² / g.
* 4: Heat treated hydrophilic silica: silica obtained by mixing and stirring the hydrophilic silica described in Table 1 and the above organopolysiloxane at 150 ° C. for 2 hours, manufactured by Shin-Etsu Chemical Co., Ltd., moisture content 1.0%, bulk density 60 g / L, primary particle diameter 12 mμ, specific surface area (BET surface area) 190 m ² / g.
[Test method]
(A) Viscosity: The viscosity was determined by measuring the viscosity (Pa · s / 25 ° C.) of the organopolysiloxane coating composition obtained in Table 1 with a B-type viscometer (No. 3 rotor).
(B) Coating film properties: Coating film properties are determined by coating each organopolysiloxane coating composition (A) to (F) on a stainless steel plate, leaving it to stand at 25 ° C. and 55% RH for 7 days, and curing it. A 2 mm coating was prepared and examined.

  Table 1 shows the results.

[Examples 1 to 4, Comparative Examples 1 to 6]
In 100 parts by weight of each organopolysiloxane coating composition (A) to (F) obtained in Table 1, silicone oil, a mixed solvent of butyl acetate and ethylcyclohexane (4 parts by weight of butyl acetate, Ethylcyclohexane (1 part by weight), xylene, “Solvesso NO100” (manufactured by Exxon Chemical Co., Ltd., solvent), and mineral spirit were sequentially added and mixed and stirred until uniform to obtain each antifouling coating composition. The property values and paint workability of each paint were investigated.

The results are shown in Table 2.
Further, an antifouling test (6 to 30 months) was performed on each antifouling paint immediately after preparation.
The results are shown in Table 3.

In Table 2, * 7, 8, 9, 10 and test methods are as follows. Moreover, (parentheses) such as various silicone oil amounts are blending amounts (parts by weight) with respect to 100 parts by weight of the organopolysiloxane (A).
* 7: “SH510”: dimethylphenyl silicone oil, viscosity: 100 centistokes, number average molecular weight Mn (polystyrene conversion): 3,400, manufactured by Toray Dow Corning Silicone.
* 8: “TSF431”: dimethylphenyl silicone oil, viscosity: 100 centistokes, number average molecular weight Mn (polystyrene conversion): 3,300, manufactured by Toshiba Silicones. * 9: “KF50”: dimethylphenyl silicone oil, viscosity: 100 centistokes, number average molecular weight Mn (polystyrene conversion): 3,300, manufactured by Shin-Etsu Chemical Co., Ltd.
* 10: “X-313-1234-99”: polyether-modified silicone oil, viscosity: 115 centistokes, number average molecular weight Mn (polystyrene conversion): 3,400, manufactured by Shin-Etsu Chemical Co., Ltd.

[Test method]
(A) Paint property value: The paint property value was measured in the same manner as in Example (A). The painting workability and antifouling test are as follows.
(B) Coating workability: 70mm x 150mm x 1mm (thick) mild steel plate is attached to the center of a 1000mm x 1000mm x 1mm (thick) tin plate, and airless spray painting is performed with the tin plate leaning vertically. The film thickness was determined after the coating film was dried, and the limit film thickness at which film sagging occurred was confirmed.
(C) Antifouling test: An epoxy base coating is applied to a 100 mm x 300 mm x 5 mm (thickness) PVC plate with a thickness of 200 µm, and each antifouling coating is applied with a brush to a dry film thickness of 150 µm. Then, after drying for 3 days, it was immersed in Miyajima Bay for 30 months, and the antifouling property was evaluated by visual observation.
(D) Evaluation of paint stability and paint workability: Further, after preparing each antifouling paint, tests were conducted on the paint state (stability) and paint workability after 3 months at 50 ° C.

The results are also shown in Table 2 above.
(E) Antifouling test: Further, after preparing an antifouling paint, an antifouling test was conducted on the antifouling paint after 3 months (storage) at 50 ° C.

The results are shown in Table 4.
The test method is as follows.
[Test method]
Paint state (stability): Put each antifouling paint shown in Table 2 in a can and leave it in a 50 ° C incubator for 3 months in a sealed state. And inspected.

[Example 5]
Viscosity at 25 ° C. having 1,000 mol of diphenylsiloxy units (—Ph ₂ SiO—, Ph: phenyl group) in one molecule and having both ends of the molecular chain (molecule) blocked with hydroxyl groups is 1,000 cS, 50 parts by weight of dimethylpolysiloxane having a number average molecular weight Mn (polystyrene equivalent) of 9,200 measured by GPC, 10 parts by weight of hydrophilic silica having a BET specific surface area of 200 m ² / g,
10 parts by weight of hydrophobic silica having a BET specific surface area of 130 m ² / g whose surface was treated with hexamethyldisilazane was stirred and mixed at 150 ° C. for 2 hours. Thereafter, the mixture was diluted with 50 parts by weight of the same dimethylpolysiloxane having 5 mol% diphenylsiloxy group in one molecule and having both ends of the molecule blocked with hydroxyl groups and having a viscosity at 25 ° C. of 1,000 cS. 10 parts by weight of oxime silane, 0.1 part by weight of dibutyltin dioctoate and 1.0 part by weight of aminopropyltrimethoxysilane were defoamed and mixed. To this composition was further added 30 parts by weight of a mixed solvent of butyl acetate and ethylcyclohexane (24 parts by weight of butyl acetate and 6 parts by weight of ethylcyclohexane) to obtain a curable silicone solution of 25 mPa · s. When this was coated on an aluminum wall surface with a coating roll, a coating thickness of 400 microns could be obtained. When this composition was cured under the conditions of 23 ° C./55% RH / 7 days, it had gloss on the surface, good transparency, durometer type A hardness: 60, and tensile strength of 4.0 MPa. A cured cured product having excellent rubber properties was obtained.
[Comparative Example 3]
Dimethylpolysiloxane having 5 mol% diphenylsiloxy units in one molecule, viscosity at 25 ° C. with both ends of the molecular chain blocked with a hydroxyl group, a viscosity of 1,000 cS, and a number average molecular weight Mn (polystyrene conversion): 9,200 50 parts by weight and 20 parts by weight of hydrophilic silica having a BET specific surface area of 200 m ² / g were stirred and mixed at 150 ° C. for 2 hours. Thereafter, the mixture was diluted with 50 parts by weight of the same dimethylpolysiloxane having 5 mol% diphenylsiloxy group in one molecule and having both ends of the molecular chain blocked with hydroxyl groups and a viscosity at 25 ° C. of 1,000 cS. 10 parts by weight of tanoxime silane, 0.1 part by weight of dibutyltin dioctoate and 1.0 part by weight of aminopropyltrimethoxysilane were defoamed and mixed. To this composition was further added 30 parts by weight of a mixed solvent of butyl acetate and ethylcyclohexane (24 parts by weight of butyl acetate and 6 parts by weight of ethylcyclohexane) to obtain a curable silicone solution of 15 mPa · s. When this was coated on an aluminum wall surface with a coating roll, it was the limit to obtain a coating thickness of 100 microns, and sagging occurred when attempting to obtain a thickness greater than that.
[Example 6]
Viscosity at 25 ° C. in which both ends of the molecular chain are blocked with a hydroxyl group is 1,000 cS (1,000 cS), number average molecular weight Mn (polystyrene conversion): 50 parts by weight of dimethylpolysiloxane of 9,400, BET specific surface area of 200 m ² 5 parts by weight of hydrophilic silica / g and 10 parts by weight of hydrophobic silica having a BET specific surface area of 130 m ² / g whose surface was treated with hexamethyldisilazane were stirred and mixed at 150 ° C. for 2 hours. Thereafter, the molecular chain was capped with hydroxyl groups at both ends and diluted with 50 parts by weight of the same dimethylpolysiloxane having a viscosity at 25 ° C. of 1,000 cS (1,000 cS), 10 parts by weight of methyltributanoxime silane, dibutyltin 0.1 parts by weight of octoate and 1.0 part by weight of aminopropyltrimethoxysilane were defoamed and mixed, and 20 parts by weight of a mixed solvent of butyl acetate and ethylcyclohexane (16 parts by weight of butyl acetate, 4 parts by weight of ethylcyclohexane). The viscosity was adjusted by addition to obtain a curable silicone composition having a viscosity of 40 mPa · s. When this composition was coated on an electronic substrate with a dispenser and cured under conditions of 23 ° C./55% RH / 7 days, a glossy silicone film having a very good appearance was formed on the substrate. . This film had physical properties of a good rubber having a durometer type A hardness of 50 and a tensile strength of 3.5 MPa.
[Comparative Example 4]
Viscosity at 25 ° C. in which both ends of the molecular chain are blocked with hydroxyl groups is 1,000 cS (1,000 cS), number average molecular weight Mn (polystyrene conversion): 50 parts by weight of 9,400 dimethylpolysiloxane, and the surface is dimethyldichlorosilane 15 parts by weight of hydrophobic silica having a BET specific surface area of 130 m ² / g treated with the above was mixed at room temperature.

Thereafter, the polymer chain is diluted with 50 parts by weight of the above dimethylpolysiloxane having both ends blocked with hydroxyl groups and a viscosity at 25 ° C. of 1,000 cS, and 10 parts by weight of methyltributanoxime silane and 0.1 parts by weight of dibutyltin dioctoate. Parts, 1.0 part by weight of aminopropyltrimethoxysilane were defoamed and mixed, and 20 parts by weight of a mixed solvent of butyl acetate and ethylcyclohexane (16 parts by weight of butyl acetate, 4 parts by weight of ethylcyclohexane) was added to adjust the viscosity. Thus, a curable silicone composition having a viscosity of 60 mPa · s was obtained.

Although this composition was coated on an electronic substrate with a dispenser, it was inferior in dischargeability from a nozzle and was cured under the conditions of 23 ° C./55% RH / 7 days. An erased silicone film was formed.
[Example 7]

Hydrophilic silica 5 having a viscosity of 700 cS and a number average molecular weight Mn (polystyrene equivalent): 50 parts by weight of 9,000 dimethylpolysiloxane and a BET specific surface area of 200 m ² / g. BE treated with hexamethyldisilazane on weight and surface
5 parts by weight of hydrophobic silica having a T specific surface area of 130 m ² / g was stirred and mixed at 150 ° C. for 2 hours. Thereafter, the polymer chain was diluted with 50 parts by weight of the same dimethylpolysiloxane having a viscosity of 700 cS having both ends blocked with hydroxyl groups and having a viscosity at 700C, then 2.0 parts by weight of zinc carbonate, 10 parts by weight of vinyltributanoxime silane, A curable silicone composition having a viscosity of 8 Pa · s was obtained by mixing 1.5 parts by weight of aminopropyltrimethoxysilane and a platinum catalyst so that the concentration of platinum atoms was 300 ppm. When this composition was dip-coated on glass fiber and cured under the conditions of 23 ° C./55% RH / 7 days, a good flame-retardant coating film having a substantially uniform film thickness of about 1 mm was obtained.
[Comparative Example 5]
Hydrophilic silica 10 having a viscosity of 700 cS and a number average molecular weight Mn (polystyrene equivalent): 50 parts by weight of 9,000 dimethylpolysiloxane and a BET specific surface area of 200 m ² / g. The parts by weight were stirred and mixed at 150 ° C. for 2 hours. afterwards,
Diluted with 50 parts by weight of the above dimethylpolysiloxane having a viscosity of 700 cS with both ends blocked with hydroxyl groups and then having a viscosity of 700 cS, then 2.0 parts by weight of zinc carbonate, 10 parts by weight of vinyltributanoxime silane, aminopropyl A curable silicone composition having a viscosity of 2 Pa · s was obtained by mixing 1.5 parts by weight of trimethoxysilane and a platinum catalyst so that the concentration of platinum atoms was 300 ppm. When this composition is dip-coated on glass fiber and cured under conditions of 23 ° C./55% RH / 7 days, dripping or dripping occurs during curing, and a flame-retardant cured product with a uniform film thickness cannot be obtained. It was.
[Example 8]
Hydrophilicity of 1,500 cS, number average molecular weight Mn (polystyrene conversion): 100 parts by weight of dimethylpolysiloxane of 10,000, BET specific surface area of 200 m ² / g. 30 parts by weight of silica, 15 parts by weight of hydrophobic silica having a BET specific surface area of 130 m ² / g, the surface of which was treated with dimethyldichlorosilane, and 10 parts by weight of an average degree of polymerization of 13 dimethylpolysiloxane having both molecular chains blocked with hydroxyl groups, The mixture was stirred and mixed at 150 ° C. for 2 hours. To this composition was further added 10 parts by weight of vinyltributanoxime silane, 1.5 parts by weight of aminopropyltrimethoxysilane, 20 parts by weight of a mixed solvent of butyl acetate and ethylcyclohexane (16 parts by weight of butyl acetate, 4 parts by weight of ethylcyclohexane). When added, a composition having a high thixotropy with a viscosity measured by a BL rotational viscometer of 50 Pa · s at 4 revolutions and 8 Pa · s at 20 revolutions was obtained. When this composition is cured at 23 ° C./55% RH / 7 days, it has gloss on the surface, good transparency, durometer type A hardness: 65, and tensile strength of 8.0 MPa. A cured coating product having the following was obtained.
[Comparative Example 6]
Hydrophilicity of 1,500 cS, number average molecular weight Mn (polystyrene conversion): 100 parts by weight of dimethylpolysiloxane of 10,000, BET specific surface area of 200 m ² / g. 45 parts by weight of silica and 10 parts by weight of dimethylpolysiloxane having an average degree of polymerization of 13 blocked at both ends of the molecular chain with hydroxyl groups were stirred and mixed at 150 ° C. for 2 hours. To this composition was further added 10 parts by weight of vinyltributanoxime silane, 1.5 parts by weight of aminopropyltrimethoxysilane, 20 parts by weight of a mixed solvent of butyl acetate and ethylcyclohexane (16 parts by weight of butyl acetate, 4 parts by weight of ethylcyclohexane). When added, the viscosity on the BL rotational viscometer was 15 Pa · s at 4 revolutions and 4 Pa · s at 20 revolutions, and the thixotropy was quite low.
[Comparative Example 7]
BET ratio in which molecular chain both ends are blocked with hydroxyl groups, viscosity at 25 ° C. is 1,500 cS, number average molecular weight Mn (polystyrene conversion): 10,000 parts by weight of dimethylpolysiloxane of 10,000, surface treated with dimethyldichlorosilane 45 parts by weight of hydrophobic silica having a surface area of 200 m ² / g and 10 parts by weight of dimethylpolysiloxane having an average polymerization degree of 13 in which both ends of the molecular chain were blocked with hydroxyl groups were stirred and mixed at room temperature for 2 hours. To this composition was further added 10 parts by weight of vinyltributanoxime silane, 1.5 parts by weight of aminopropyltrimethoxysilane, 20 parts by weight of a mixed solvent of butyl acetate and ethylcyclohexane (16 parts by weight of butyl acetate, 4 parts by weight of ethylcyclohexane). When added, the viscosity with a BM rotational viscometer was 550 Pa · s at 4 rotations and 120 Pa · s at 20 rotations, but the thixotropy was high but extremely high.
[Example 9]
The molecular chain both ends are blocked with a trimethoxysiloxy group (—O—Si— (OCH ₃ ) ₃ ), the viscosity at 25 ° C. is 1,000 cS (1,000 cS), the number average molecular weight Mn (polystyrene conversion): 9 , 300 dimethylpolysiloxane 50 parts by weight, 15 parts by weight of hydrophobic fumed silica having a BET specific surface area of 130 m ² / g treated with hexamethyldisilazane on the surface,
Stir and mix for 2 hours at ° C. Thereafter, both ends of the molecular chain were blocked with a trimethoxysiloxy group, and the viscosity at 25 ° C. was 1,000 cS (1,000 cS).
Diluted in parts by weight, 5 parts by weight of methyltrimethoxysilane, 0.1 part by weight of dibutyltin dioctate, 1.0 part by weight of aminopropyltrimethoxysilane were defoamed and mixed, and 10 parts by weight of butyl acetate and ethylcyclohexane The mixed solvent (8 parts by weight of butyl acetate and 2 parts by weight of ethylcyclohexane) was added to adjust the viscosity to obtain a curable silicone composition (L) (curable composition L) having a viscosity of 6 Pa · s. When this composition was cured under conditions of 23 ° C./55% RH / 7 days, a glossy silicone film having a very good appearance was formed on the substrate. The cured product had good rubber properties with a durometer type A hardness of 40 and a tensile strength of 2.7 MPa. (According to JIS 6249)
[Comparative Example 8]
Molecular chain both ends blocked with trimethoxysiloxy group, viscosity at 25 ° C. is 1,000 cS (1,000 cS), number average molecular weight Mn (polystyrene conversion): 50 parts by weight of 9,300 dimethylpolysiloxane, BET ratio 15 parts by weight of hydrophobic fumed silica having a surface area of 200 m ² / g was stirred and mixed at room temperature for 2 hours. Thereafter, both ends of the molecular chain were blocked with trimethoxysiloxy groups and diluted with 50 parts by weight of the same dimethylpolysiloxane having a viscosity at 25 ° C. of 1,000 cS, and 5 parts by weight of methyltrimethoxysilane, dibutyltin dioctoate 0 .1
Part by weight, 1.0 part by weight of aminopropyltrimethoxysilane are defoamed and mixed, and 10 parts by weight of a mixed solvent of butyl acetate and ethylcyclohexane (8 parts by weight of butyl acetate, 2 parts by weight of ethylcyclohexane) is added to the viscosity. Thus, a curable silicone composition (M) having a viscosity of 13 Pa · s was obtained. Although this composition (M) was coated on the electronic substrate with a dispenser, it was inferior in dischargeability from the nozzle as compared with the composition of Example 9, and was cured under conditions of 23 ° C./55% RH / 7 days. As a result, a milky surface-matte silicone coating film was formed on the substrate. This cured product had a durometer type A hardness of 35 and a tensile strength of 2.0 MPa. (According to JIS 6249)
As described above, according to Examples 5 to 9 and Comparative Examples 3 to 8, the curable composition of the present invention has low viscosity and high thixotropy, excellent workability at the time of coating, and coating film. It can be seen that it is excellent in strength, surface smoothness and the like.
[Examples 10 to 13 and Comparative Examples 9 to 16]
In Example 1, instead of the organopolysiloxane composition (A), in Examples 10 to 13 and Comparative Examples 13 to 16, the curable silicone composition (L) described in Example 9 was used. In Nos. 9 to 12, the curable silicone composition (M) described in Comparative Example 8 was used, and silicone oil, a mixed solvent of butyl acetate and ethylcyclohexane (butyl acetate 4 parts by weight, ethylcyclohexane 1 part by weight), xylene, and solvesso An antifouling paint composition was prepared in the same manner as in Example 1 except that NO100 and mineral spirit were used in the amounts shown in Table 5, and various physical properties were evaluated in the same manner as in Example 1.

The results are shown in Tables 5-8.
Table 5 shows the property values and paint workability when made into paint as in Table 2, Table 6 shows the antifouling property after paint as in Table 3, and Table 7 shows a predetermined period. The property values of the paint after storage are shown, and Table 8 shows the antifouling property of the paint after storage in the same manner as in Table 4.

Claims (26)

(A) an organopolysiloxane having a number average molecular weight Mn (polystyrene conversion) measured by GPC of 500 to 25000 and both ends of the molecule being condensation-reactive functional groups;
(B) A curable composition containing silica. The silica (B) is
(i) hydrophobic silica, or
The curable composition according to claim 1, comprising (ii) hydrophobic silica and hydrophilic silica. The organopolysiloxane (A) has the following formula [α]:

(Wherein, W represents a hydroxyl group or a hydrolyzable group, R ¹ and R each independently represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 12 carbon atoms, and a plurality of R ¹ And R may be the same as or different from each other, n represents an integer of 5 or more, and a represents 0, 1 or 2.)
The curable composition according to any one of claims 1 to 2. In addition to the component (A) in which W in the formula [α] is a hydroxyl group and a is 2, and the component (B),
(C) Formula [I]: R ¹ _a SiX _4-a (In Formula [I], R ¹ represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, and X represents a hydrolyzable group. And a represents 0 or 1.)
The curable composition according to any one of claims 2 to 3, comprising an organosilane represented by the formula (1) or a partial hydrolyzate thereof.   The curable composition according to any one of claims 2 to 4, wherein the hydrophilic silica is heat-treated at a temperature of 100 ° C or higher with the component (A).   The curable composition according to any one of claims 1 to 5, wherein the component (B) is contained in an amount of 1 to 100 parts by weight with respect to 100 parts by weight of the component (A).   The curable composition according to any one of claims 4 to 6, wherein the component (C) is contained in an amount of 1 to 20 parts by weight with respect to 100 parts by weight of the component (A). The hydrophobic silica (a) and the hydrophilic silica (b) are in a weight ratio ((a) / (b)) = 1/99 to 99.
The curable composition according to any one of claims 2 to 7, which is contained at 1/1.   Furthermore, the silicone oil (D) is contained in an amount of 0.1 to 200 parts by weight in total with respect to 100 parts by weight of the component (A). The curable composition as described.   The curable composition according to claim 9, wherein the silicone oil (D) has a viscosity (measured by GPC at 25 ° C.) of 20 to 120 cst.   Furthermore, butyl acetate and / or ethylcyclohexane are included as a solvent (E), The curable composition in any one of Claims 1-10 characterized by the above-mentioned.   The curable composition according to any one of claims 1 to 11, wherein a non-volatile content in the curable composition is 90% or more.   Furthermore, the curable composition in any one of Claims 1-12 containing a catalyst, an antifouling agent, and / or a coloring agent.   The production of the curable composition comprises a step of heat-treating the component (A) and at least the hydrophilic silica of the component (B) at a temperature of 100 ° C or higher. Item 14. A method for producing a curable composition according to any one of Items 2 to 13.   The coating composition which consists of a curable composition in any one of the said Claims 1-14.   The composition according to claim 15, wherein the coating composition is a paint.   The composition according to claim 16, wherein the paint is an antifouling paint.   Hardened | cured material formed by hardening | curing the curable composition as described in any one of Claims 1-13. The coating film which consists of a curable composition as described in any one of Claims 1-13. The antifouling coating film which consists of a curable composition as described in any one of Claims 1-13.   The base material with a coating film characterized by the surface of the base material being coat | covered with the coating film formed by hardening | curing the curable composition in any one of Claims 1-13.   The surface of the base material which contacts seawater or fresh water is covered with a coating film obtained by curing the curable composition according to any one of claims 1 to 13. .   The antifouling substrate according to claim 22, wherein the substrate is any one of an underwater structure, a ship outer plate, a fishing net, and fishing gear.   A coating material comprising the curable composition according to any one of claims 1 to 13 is applied or impregnated on a surface of a base material, and then the coating material is cured to form a coating film. A method for forming a coating film on a substrate surface.   Applying or impregnating the antifouling paint comprising the curable composition according to any one of claims 1 to 13 on the surface of the substrate, and then curing the antifouling paint to form an antifouling coating film. An antifouling method for a substrate, which is characterized. The antifouling method for a base material according to claim 25, wherein the base material is any one of an underwater structure, a ship outer plate, a fishing net, and fishing gear.