EP4590775A1

EP4590775A1 - Cross-linkable composition and method for producing coating layer using the composition

Info

Publication number: EP4590775A1
Application number: EP24702487.0A
Authority: EP
Inventors: Noboru Kuroda; Chika MOTOMURA
Original assignee: Wacker Chemie AG
Current assignee: Wacker Chemie AG
Priority date: 2023-02-27
Filing date: 2024-01-23
Publication date: 2025-07-30
Also published as: JP2024121795A; CN120019122A; WO2024179752A1; KR20250097965A

Abstract

Provided is a cross-linkable composition that can be cured to form a coating layer which has good repeated paintability and excellent repeated removability, is smooth, and exhibits a certain hardness. The cross-linkable composition includes a diorganopolysiloxane whose molecular chain terminals are blocked with a triorganosilyl group as a component (A)-(I), a diorganopolysiloxane having a specific amino group and a specific alkoxy group as a component (A)- (II), a certain silane and/or a partial hydrolysate thereof as a component (B), an alkoxysilane having two or more alkoxy groups having 5 or less carbon atoms as a component (C), and an organosilicon compound having a group containing an NH2 group as a component (D).

Description

CROSS -LINKABLE COMPOSITION AND METHOD FOR PRODUCING COATING LAYER USING THE COMPOSITION

Technical Field

[0001] The present invention relates to a cross-linkable composition based on an organosilicon compound, and a production method and use of the cross-linkable composition, in particular, a use of the cross-linkable composition for forming a coating layer that allows repeated painting and repeated removal .

[0002] Graffiti on the surfaces of exterior walls of buildings, stone structures, railway vehicles, bridge piers, fences, traffic signs, and the like has become a social problem. Thus, anti-graffiti sheets and coatings have been developed .

[0003] For example, PTL 1 has an object of providing a silicone composite antifouling sheet that exhibits a stable long-term antifouling property, cleanability, easiness of cleaning, and wear resistance, can be easily attached to an adherend, and can conform its shape to cracks and shifts on the applied surface. PTL 1 thus discloses a silicone composite antifouling sheet including a substrate layer composed of a fluororesin and a silicone adhesive layer laminated on one surface of the substrate layer.

[0004] PTL 2 discloses a cross-linkable composition that can be used in anti-graffiti coating that, without pretreatment using a primer, adheres well to the subsurface, but is for the most part not adhered to by graffiti.

[0005] All of the sheets and coatings for preventing graffiti represented by the above-mentioned literatures have properties that make it difficult for graffiti to adhere and that make it easy to remove graffiti. The surface on which graffiti hardly adheres thus has poor paintability, causing a problem in that it cannot be painted with a sufficient aesthetic appearance. Furthermore, in PTL 1, although graffiti can be removed with an adhesive tape, there is also a problem in that it takes time and labor to remove graffiti over a wide area. Citation List Patent Literature [0006] PTL 1: Japanese Patent Application Laid-Open No.

2022-092493

PTL 2: Japanese Translation of PCT Patent Application Publication No. 2019-527245 (corresponding to WO2018/ 162033 ) Summary Of Invention Technical Problem [0007] In recent years, the following paint usage is becoming more and more popular. That is, a paint is applied to a surface of a concrete wall or the like, and after the paint is viewed for a certain period of time, it is removed and replaced with another paint. Alternatively, paints, notes, or the like on an iron board for outdoor use are repeatedly erased and replaced.

In such a usage, it is necessary to form a coating layer that not only allows easy removal of the paint attached to the layer, but also has good paintability and writability to prevent the paint from being repelled or washed out.

Furthermore, in order to apply the paint with a good appearance, the coating layer, which is the surface to be painted, needs to be smooth and have a certain degree of hardness .

Especially when a large painting surface is used outdoors, it is required that the paint be able to be removed from the coating layer with a stream of water instead of a solvent, a dry eraser, an adhesive tape, or the like from the viewpoints of easiness of work, reduction of environmental impact, and safety. [0008] For example, an anti-graffiti coating using the composition disclosed in PTL 2 has a problem in which a paint to be applied to the coating surface does not adhere to it for the most part, resulting in a painting failure, or the paint is repelled on the coating surface, making it difficult to maintain a sufficient aesthetic appearance.

[0009] In view of the above-described circumstances, an object of the present invention is to provide a cross-linkable composition that can be cured to form a coating layer that has good repeated paintability, excellent repeated removability, and a certain hardness.

Solution To Problem

[0010] The present inventors have found that the above- mentioned problems can be solved by a cross-linkable composition including a component (A) - (I) that is a diorganopolysiloxane whose molecular chain terminals are blocked with a triorganosilyl group, a component (A) - (II) that is a diorganopolysiloxane having a specific amino group and a specific alkoxy group, a component (B) that is a certain silane and/or a partial hydrolysate thereof, a component (C) that is an alkoxysilane having two or more alkoxy groups having 5 or less carbon atoms, and a component (D) that is an organosilicon compound having a group containing an NH2 group, thereby completing the present invention.

[0011] Specifically, the present invention provides a cross-linkable composition including: a component (A) - (I) that is a diorganopolysiloxane having a linear or branched structure whose molecular chain terminals are blocked with a triorganosilyl group; a component (A) - (II) that is a diorganopolysiloxane having a linear or branched structure having, per molecule, at least two (R²R³NCH2) groups and at least four (OR⁴) groups (R² represents a hydrogen atom or an optionally substituted monovalent linear or branched hydrocarbon group having 1 to 6 carbon atoms,

R³ is an optionally substituted monovalent linear or branched hydrocarbon group having 1 to 6 carbon atoms, a cyclic saturated hydrocarbon group having 5 or 6 carbon atoms, or a phenyl group, and

R⁴s, which may be the same as or different from each other, each represent an optionally substituted monovalent hydrocarbon group) ; a component (B) that is a silane represented by the following formula (1) and/or a partial hydrolysate thereof, (R²R³NCH₂) Si (OR⁴) 3 (1) ; a component (C) that is an alkoxysilane represented by the following formula (2) ,

R²¹4-xSi (OR²²) _x (2)

(in the formula (2) , R²¹(s) , which may be the same as or different from each other, represents an optionally substituted monovalent hydrocarbon group having 1 to 6 carbon atoms, and

R²²s, which may be the same as or different from each other, each represent an optionally substituted monovalent hydrocarbon group having 1 to 5 carbon atoms, with x being 2, 3, or 4 ) ; and a component (D) that is an organosilicon compound including a unit represented by the following formula (3) , in which at least one group D is present per molecule, and at least one group D has an NH₂ group,

DfSl (OR³²) _eR³¹dO(4-d-e-f)/₂ (3)

(in the formula (3) , R³¹(s) , which may be the same as or different from each other, represents an optionally substituted, nitrogen-free monovalent SiC-bonded organic group,

R³²(s) , which may be the same as or different from each other, represents a hydrogen atom or an optionally substituted hydrocarbon group,

D(s) , which may be the same as or different from each other, represents a monovalent SiC-bonded group having at least one nitrogen atom not bonded to a carbonyl group (C=0) , d is 0 or 1, e is 0, 1, 2, or 3, f is 0 or 1, and the sum of d, e, and f is 4 or less) . [0012] The above-mentioned cross-linkable composition is applied to a substrate such as concrete and cured to form a coating layer. The coating layer exhibits good paintability without cissings or the like when a paint is applied to a surface of the coating layer and also exhibits good removability whereby few paint residues remain when the applied paint is removed. Furthermore, the coating layer maintains good paintability and removability after multiple application/removal cycles. Thus, the coating layer is useful as a coating layer that allows repeated painting and repeated removal .

[0013] The paint applied to the coating layer of the present invention is not particularly limited. Examples of the paint includes a lacquer, a powder paint, an aqueous (water-based) paint, and a synthetic resin paint such as an epoxy resin paint, a urethane resin paint, a fluororesin paint, a polyester resin paint, a melamine resin paint, and an acrylic resin paint.

[0014] The cross-linkable composition of the present invention may be in any aspect and form as long as it is in the form of at least one liquid or more and can be cured by moisture to finally form a cured product of the composition.

[0015] The component (A) - (I) has good compatibility with each of the components (A) - (IT) , (B) , (C) , and (D) , which are silanes or siloxanes. Thus, the component (A) - (I) in the uncured state exists in a state of being uniformly dispersed in the cross-linkable composition that includes these components. When the cross-linkable composition, in which each component is uniformly mixed, is applied to a substrate such as concrete or wood, it undergoes a cross-linking reaction with a water content such as moisture in the air and produces a coating layer by moisture-curing. The formed coating layer includes a matrix formed by cross-linking of the components (A) - (II) , (B) , (C) , and (D) , and also includes the component (A) - (I) dispersed in the matrix without participating in the cross-linking reaction.

In this process, the (R²R³NCH2) group and the (OR⁴) group possessed by the component (A) - (II) and the NH2 group possessed by the component (D) promote adhesion of the coating layer to the substrate, so that the coating layer adheres well to the substrate .

On the other hand, since the component (A) - (I) having no cross-linkable group does not participate in matrix formation, the component (A) - (I) bleeds to the surface of the coating layer over time after the cross-linkable composition is cured. When a paint or the like is applied to the surface of the coating layer, the paint can be removed by a solvent, scrubbing with a cloth, sponge, or the like, an adhesive tape, or the like. However, since the component (A) - (I) has water repellency and oil repellency, the paint can be easily removed with a stream of water without using a solvent, an adhesive tape, or the like.

[0016] If the bleeding amount of the component (A) - (I) is excessive, although the paint can be easily removed, the paint is repelled by the coating surface, causing a problem in that the paint cannot be applied with a sufficient aesthetic appearance .

However, in the present invention, the presence of the component (C) , i.e., the alkoxysilane in the matrix increases the hardness of the coating layer, and at the same time, reduces the bleeding amount of the component (A) - (I) to the surface of the coating layer compared to a case without the component (C) . Thus, even with a coating layer obtained by curing the composition including the component (A) - (I) , it is possible to paint the surface with a sufficient aesthetic appearance without cissings. Furthermore, even when the coating layer includes the component (C) , a certain amount of the component (A) - (I) bleeds to the surface of the coating layer, so that the removability of the paint can be maintained .

In the coating layer including the component (C) , the component (A) - (I) , because of its water repellency, remains on the surface of the coating layer without being washed out when the paint is removed with a stream of water, and the component (A) - (I) bleeds from the inside of the coating layer little by little over a long period of time. Thus, even if the painting and the paint removal are repeatedly performed, the characteristic that the paint can be easily removed is maintained for a long period of time.

[0017] Furthermore, it is confirmed that the hardness of the coating layer including the component (C) is enhanced compared to the coating layer that does not include the component (C) or compared to the coating layer that includes an alkoxysilane having two or more alkoxy groups with 6 or more carbon atoms. The high-hardness coating layer is less susceptible to cracking and peeling from the substrate even when the paint is repeatedly applied and removed. Thus, it is particularly suitable for long-term repeated use and outdoor use .

[0018] The component (C) itself also has a low viscosity and reduces the viscosity of the cross-linkable composition as a whole before curing. Thus, the workability of the composition is good when it is applied to a substrate. Since the composition can be applied uniformly and thinly, a smooth surface of the coating layer can be obtained, allowing paint that is applied to the coating surface to exhibit a good aesthetic appearance.

Description Of Embodiments

[0019] Hereinafter, the present invention will be described in detail.

[0020] According to a first aspect of the present invention, the cross-linkable composition includes: a component (A) - (I) that is a diorganopolysiloxane having a linear or branched structure whose molecular chain terminals are blocked with a triorganosilyl group; a component (A) - (II) that is a diorganopolysiloxane having a linear or branched structure having, per molecule, at least two (R²R³NCH2) groups and at least four (OR⁴) groups

(R² represents a hydrogen atom or an optionally substituted monovalent linear or branched hydrocarbon group having 1 to 6 carbon atoms,

R⁴s, which may be the same as or different from each other, each represent an optionally substituted monovalent hydrocarbon group) ; a component (B) that is a silane represented by the following formula (1) and/or a partial hydrolysate thereof, (R²R³NCH₂) Si (OR⁴) ₃ (I) ; a component (C) that is an alkoxysilane represented by the following formula (2) ,

R²¹4-xSi (OR²²) _x (2)

DfSi (OR³²) eR³¹dO ( 4-d-e-f ) /₂ (3)

D(s) , which may be the same as or different from each other, represents a monovalent SiC-bonded group having at least one nitrogen atom not bonded to a carbonyl group (C=0) , d is 0 or 1, e is 0, 1, 2, or 3, f is 0 or 1, and the sum of d, e, and f is 4 or less) .

[0021] The above-mentioned cross-linkable composition may serve as a composition for forming a coating layer that allows repeated painting according to a second aspect of the present invention .

The term "coating layer that allows repeated painting" described herein refers to a coating layer that has 10 or less cissings with a diameter (|) of 2 mm or less ((|) < 2 mm) per square meter (/m²) and no cissings with a diameter (|) of 2 mm or more ((|) > 2 mm) per square meter, as determined by a repeated paintability evaluation method described below.

Repeated paintability evaluation method:

A cross-linkable composition is applied to a substrate and then cured to form a coating layer.

On the surface of the resulting coating layer, acrylic lacquer spray (brown) manufactured by Nippon Paint Co., Ltd. is sprayed in an area of 30 cm x 20 cm from 30 cm above the surface of the coating layer (before drying, the application amount is 100 g/m²) . After standing for 2 hours, the paint is removed by jetting water against the paint at a distance of 10 cm from the surface of the coating layer using a household high-pressure washer. These processes are repeated 10 times to obtain a surface evaluation test piece for repeated paintability evaluation.

On the surface evaluation test piece for repeated paintability evaluation, the acrylic lacquer spray (brown) manufactured by Nippon Paint Co., Ltd. is sprayed in an area of 30 cm x 20 cm from 30 cm above the surface of the coating layer, and the presence or absence of cissings is visually inspected .

The following is the evaluation criteria for repeated paintabiilty .

A: No visible cissings

B: More than 0 and less than 10 cissings (with (|) < 2 mm) /m² and no cissings with (|) > 2 mm

C: 10 or more cissings (with (|) < 2 mm) /m², more than 0 and less than 10 cissings (with 2 mm < (|) < 5 mm) /m², and no cissings with (|) > 5 mm

D: 10 or more cissings (with 2 mm < (|) < 5 mm) /m² and no cissings with (|) > 5 mm

E: There are cissings with (|) > 5 mm

Thus, the coating layer obtained by curing the crosslinkable composition according to the present invention is evaluated as the rank A or B by the above-described evaluation method .

[0022] The cross-linkable composition may be a crosslinkable composition according to a third aspect of the present invention characterized in that the cross-linkable composition includes the components (A) - (I) , (A) - (IT) , (B) , (C) , and (D) , and the addition of the component (C) enhances repeated paintability of the coating layer obtained by curing the cross-linkable composition.

[0023] Component (A) - (I) :

The component (A) - (I) bleeds from the inside of the coating layer to the surface of the coating layer after the cross-linkable composition is cured and this component facilitates removal of a paint applied to the surface of the coating layer. [0024] Specifically, the component (A) - (I) is a nonfunctional diorganopolysiloxane having a linear or branched structure whose molecular chain terminals are blocked with a triorganosilyl group where the structure has a main chain being composed of a diorganosiloxane unit as a repeating unit. Specifically, the main chain is composed of a repeating unit represented by the following formula (4) wherein c is 1 or 2 : R_cSiO₄-c/2 (4) .

The number of the repeating units per molecule (degree of polymerization) of the component (A) - (I) may be 1 to 500, and is preferably 10 to 200, and more preferably 10 to 100. The degree of polymerization may be measured, for example, as the number-average degree of polymerization (or number-average molecular weight) in terms of polystyrene-equivalent value in gel permeation chromatography analysis using toluene or the like as a developing solvent.

[0025] The component (A) - (I) may contain an Si-OH group at the molecular chain terminals and/or a part of the side chain of the molecular chain. In this case, the content of the Si- OH group is preferably 5 mol % or less, more preferably 1 mol % or less, and even more preferably 0.1 mol % or less with respect to R in the component (A) - (I) .

[0026] The groups R (when c is 2) are independently determined, and examples of the group R include an alkyl group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a 1-n-butyl group, a 2-n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a hexyl group such as an n-hexyl group, a heptyl group such as an n-heptyl group, an octyl group such as an n-octyl group and an iso-octyl group including a 2 , 2 , 4-trimethylpentyl group, a nonyl group such as an n-nonyl group, a decyl group such as an n-decyl group, a dodecyl group such as an n-dodecyl group, and an octadecyl group such as an n-octadecyl group, a cycloalkyl group such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a methylcyclohexyl group, an alkenyl group such as a 1-propenyl group and a 2-propenyl group, an aryl group such as a phenyl group, a naphthyl group, an anthryl group, and a phenanthryl group, an arkaryl group such as an o-tolyl group, an m-tolyl group, a p-tolyl group, a xylyl group, and an ethylphenyl group, and an aralkyl group such as a benzyl group, an a-phenylethyl group, and a 0- phenylethyl group.

[0027] When R is a substituted group and c is 2, the groups R are each independently determined, and examples of the group R include a haloalkyl group such as a 3,3,3- trif luoroprop-l-yl group, a 1 , 1 , 1 , 3 , 3 , 3-hexaf luoroprop-2-yl group, and a heptaf luoroprop-2-yl group.

[0028] The group R is preferably a monovalent hydrocarbon group having 1 to 18 carbon atoms, optionally substituted with a halogen atom, more preferably an alkyl group, and particularly preferably a methyl group.

[0029] The component (A) - (I) used in the present invention is preferably a liquid at 25°C and 1, 000 hPa .

[0030] The component (A) - (I) used in the present invention may have a viscosity, at 25°C, of 20 mPa-s to 100, 000 mPa-s, preferably 50 mPa-s to 10, 000 mPa-s, and even more preferably 70 mPa-s to 500 mPa-s.

One type of diorganopolysiloxanes with the viscosity falling within the above-mentioned range may be used alone as the component (A) - (I) or two or more types thereof may be used in combination as appropriate. When the viscosity falls within the above-mentioned range, the viscosity of the crosslinkable composition as a whole before curing falls within an appropriate range, so that the workability is good and the smoothness of the obtained coating layer is good. Particularly in use applications where the viscosity of the cross-linkable composition as a whole needs to be kept low so that workability needs to be improved, the viscosity may be in the range of 70 mPa-s to 500 mPa-s, for example. On the other hand, suppose a case where a high viscosity of the entire cross-linkable composition is permitted and it is necessary to make the bleeding rate of the component (A) - (I) slow while maintaining the repeated paintability and repeated removability of the resulting coating layer over a longer period of time. In this case, it is possible to use a compound having a higher viscosity as a part or all of the component (A) - (I) .

Note that the viscosity described herein is a value measured at 25°C and at a shear rate of 10/s using a rotational viscometer (according to JIS K 7117-2) unless otherwise specified .

[0031] The blending amount of the component (A) - (I) may be

1 part by mass or more and less than 20 parts by mass, more preferably 2 parts by mass or more and 15 parts by mass or less, and even more preferably 5 parts by mass or more and 10 parts by mass or less, relative to 100 parts by mass of the total amount of the components (A) - (I) and (A) - (II) .

When the content of the component (A) - (I) falls within the above-mentioned range, it is possible to suppress a phenomenon in which the surface of the coating layer sticks or the coating layer repels the paint applied to its surface. [0032] The component (A) - (I) (diorganopolysiloxane) may be selected from compounds commercially available or prepared by methods known to those skilled in the art.

[0033] Component (A) - (II) :

The component (A) - (II) is a main component constituting the matrix formed by curing of the cross-linkable composition, and also serves to promote favorable adhesion of the coating layer obtained after curing to a substrate.

[0034] The component (A) - (II) is a diorganopolysiloxane having a linear or branched structure having, per molecule, at least two (R²R³NCH2) groups and at least four (OR⁴) groups. Specifically, the component (A) - (II) is composed of repeating units represented by the following formula (4) and the following formula (5) , where the following formula (4) is the same as that for the component (A) - (I) :

R_cSiO₄-c/2 (4) , and

(R²R³NCH₂) (OR⁴)_mSiO₃-m/2 (5) .

Herein, R² represents a hydrogen atom or an optionally substituted monovalent linear or branched hydrocarbon group having 1 to 6 carbon atoms,

R⁴s, which may be the same as or different from each other, each represent an optionally substituted monovalent hydrocarbon group.

[0035] The degree of polymerization of the main chain per molecule of the component (A) - (II) may be 1 to 2500, preferably 10 to 1000, and more preferably 10 to 800.

One type of diorganopolysiloxanes having the degree of polymerization of the main chain falling within the above- mentioned range may be used alone as the component (A) - (II) or two or more types thereof may be used in combination as appropriate. When the degree of polymerization falls within the above-mentioned range, it is possible to set the hardness of the coating layer obtained from the cross-linkable composition to a suitable range.

[0036] The component (A) - (II) may contain an Si-OH group at the molecular chain terminal and/or a part of the side chain of the molecular chain. In this case, the content of the Si-OH group is preferably 5 moll or less, more preferably 1 moll or less, and even more preferably 0.1 moll or less with respect to (OR⁴) in the component (A) - (II) .

[0037] Examples of the hydrocarbon group R² include an alkyl group such as a methyl group, an ethyl group, an n- propyl group, an isopropyl group, a 1-n-butyl group, a 2-n- butyl group, an isobutyl group, a tert-butyl group, an n- pentyl group, an isopentyl group, a neopentyl group, a tertpentyl group, and a hexyl group such as an n-hexyl group . [ 0038 ] The group R² is preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, or a 1 -n- butyl group, more preferably an ethyl group or a 1 -n-butyl group, or particularly preferably an n-butyl group .

[ 0039 ] Examples of the group R³ include an alkyl group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a 1 -n-butyl group, a 2 -n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, and a hexyl group such as an n-hexyl group, a cycloalkyl group such as a cyclopentyl group and a cyclohexyl group, and a phenyl group .

[ 0040 ] The group R³ is preferably a methyl group, an ethyl group, an n-propyl group, a 1 -n-butyl group, or a cyclohexyl group, more preferably an ethyl group, an n-butyl group, or a cyclohexyl group, or particularly preferably an n-butyl group . [ 0041 ] It is preferable that the groups R² and R³ be the same group .

[ 0042 ] The group (R²R³NCH2 ) is preferably an N, N- dimethylaminomethyl group, an N, N-diethylaminomethyl group, an N, N-di-n-propylaminomethyl group, an N, N-di-n-butylaminomethyl group, an N-n-butylaminomethyl group, an N-butan-2- ylaminomethyl group, an N-cyclopentylaminomethyl group, or an N, N-cyclohexylaminomethyl group, more preferably an N, N- dimethylaminomethyl group, an N, N-diethylaminomethyl group, an N, N-di-n-propylaminomethyl group, or an N, N-di-n- butylaminomethyl group, or particularly preferably an N, N-di- n-butylaminomethyl group .

[ 0043 ] Examples of the group R⁴ include those defined for the group R . Speci fically, the groups R⁴ are preferably each independently an alkyl group having 1 to 6 carbon atoms , particularly preferably a methyl or ethyl group .

[ 0044 ] The blending amount of the component (A) - ( I I ) may be 80 parts by mass or more and less than 99 parts by mass, more preferably more than 85 parts by mass and less than 98 parts by mass, and even more preferably more than 90 parts by mass and less than 95 parts by mass or less, relative to 100 parts by mass of the total amount of the components (A) - (I) and (A) - (II) .

The total amount of the components (A) - (I) and (A) - (II) may be 20 parts by mass or more and 95 parts by mass or less, more preferably 30 parts by mass or more and 90 parts by mass or less, and even more preferably 40 parts by mass or more and 85 parts by mass or less, relative to 100 parts by mass of the total amount of the cross-linkable composition as a whole.

When the contents of the components (A) - (I) and (A) - (II) fall within the above-mentioned respective ranges, it is possible to achieve both good removability and good paintability .

[0045] The component (A) - (II) used in the present invention is an already-known compound and can be prepared, for example, by dealcoholizing an a,o- dihydroxydiorganopolysiloxane (A0) with a silane represented by the formula (1) .

(R²R³NCH₂) Si (OR⁴) ₃ (1)

If desired, the component (A) - (II) can also be prepared in situ during the production of the cross-linkable composition according to the present invention. The a,o- dihydroxydiorganopolysiloxane (A0) used for preparing the component (A) - (II) used in the present invention has a numberaverage molar mass Mn of preferably less than 45,000 g/mol, more preferably less than 40,000 g/mol, even more preferably less than 35,000 g/mol, and particularly preferably less than 30, 000 g/mol . [0046] The units represented by the formula (4) present in the component (A) - (II) used in the present invention are preferably those with c being 2, essentially. As a result of the preparation, the component (A) - (II) may also include units represented by the formula (4) with c being 1. The component (A) - (II) used according to the present invention preferably includes, per molecule, at most one unit represented by the formula (4) with c being 1, and particularly preferably does not include that unit.

[0047] The component (A) - (II) used in the present invention is preferably represented by the following formula (6) :

[ (R⁴O) ₂ (R²R³NCH₂) SiO- (SiR₂O) _n-J o (OR⁴) ₂-o (R²R³NCH₂) SiO-

(SiR₂O) n-Si (R²R³NCH₂) (OR⁴) ₂-O [0- (SiR₂O) n-Si (R²R³NCH₂) (0R⁴) ₂] _O (6)

In the formula (6) , o may be the same as or different from one another and represents 0, 1, or 2. Further, n may be the same or different and represents an integer of from 10 to 600.

[0048] The - (SiR₂O)_n- moieties in the formula (6) each independently have a number-average molar mass Mn of preferably less than 45,000 g/mol, more preferably less than 40,000 g/mol, even more preferably less than 35,000 g/mol, and particularly preferably less than 30,000 g/mol.

[0049] Examples of the component (A) - (II) used in the present invention include:

(EtO) 2 [ (n-C₄H₉) 2NCH2] SiO- (SiMe₂O) _X-Si [CH₂N (n-C₄H₉) 2] (OEt) 2, (EtO) 2 [ (n-C₄H₉) 2NCH2] SiO- (SiMe₂O) _x (OEt) [ (n-C₄H₉) 2NCH2] SiO- (SiMe₂O) _X-Si [CH₂N(n-C₄H₉) 2] (OEt) 2,

(EtO) 2 [ (n-C₄H₉) 2NCH2] SiO- (SiMe₂O) _x (OEt) [ (n-C₄H₉) 2NCH2] SiO- (SiMe₂O) _X-Si [CH₂N(n-C₄H₉) 2] (OEt) - (SiMe₂O) _X-Si [CH₂N (n-C₄H₉) 2] (OEt) 2, [ (EtO) 2 [ (n-C₄H₉) 2NCH2] SiO- (SiMe₂O) _x] 2 [ (n-C₄H₉) 2NCH2] SiO- (SiMe₂O) _X-Si [CH₂N(n-C₄H₉) 2] ( (OEt) 2,

[ (EtO) 2 [ (n-C₄H₉) 2NCH2] SiO- (SiMe₂O) _x] 2 [ (n-C₄H₉) 2NCH2] SiO- (SiMe₂O) _X-Si [CH₂N(n-C₄H₉) 2] (OEt) - (SiMe₂O) _X-Si [CH₂N (n-C₄H₉) 2] (OEt) 2, and

[ (EtO) 2 [ (n-C₄H₉) 2NCH2] SiO- (SiMe₂O) _x] 2 [ (n-C₄H₉) 2NCH2] SiO- (SiMe₂O) _X-Si [CH₂N(n-C₄H₉) 2] [- (SiMe₂O) _X-Si [CH₂N (n-C₄H₉) 2] (OEt) 2] 2. Specifically, the component (A) - (II) is preferably (EtO) 2 [ (n- C₄H₉) 2NCH2] SiO- (SiMe₂O) _X-Si [CH₂N(n-C₄H₉) 2] (OEt) 2 or (EtO) 2 [ (n- C₄H₉) 2NCH2] Sio- (SiMe₂O) _x (OEt) [ (n-C₄H₉) ₂NCH₂] SiO- (SiMe₂O) _x-

Si [CH2N (n-C₄H₉) 2] (OEt) 2, and particularly preferably (EtO) 2 [ (n- C₄H₉) 2NCH2] SIO- (SlMe₂O) _X-S1 [CH₂N(n-C₄H₉) 2] (OEt) 2. In the formulas, Me is a methyl group, Et is an ethyl group, and x may be the same as or different from one another, and represents an integer of 10 to 405.

[0050] The component (A) - (II) used in the present invention is preferably a liquid at 25°C and 1,000 hPa . [0051] The component (A) - (II) used in the present invention may have a viscosity, at 25°C, of 400 mPa-s to 20,000 mPa-s, preferably 800 mPa-s to 15, 000 mPa-s, and even more preferably 1, 000 mPa-s to 10, 000 mPa-s. When the viscosity thereof falls within this range, the viscosity of the crosslinkable composition as a whole before curing falls within an appropriate range, and thus the workability and the smoothness of the obtained coating layer are good.

[0052] Component (B) :

The component (B) in the present invention is a silane represented by the following formula (1) and/or a partial hydrolysate thereof:

(R²R³NCH₂) Si (OR⁴) 3 (1) .

The component (B) used in the present invention is an already-known compound and can be readily prepared by common methods in silicon chemistry.

[0053] Examples of the component (B) used in the present invention include:

N, N- dimethyl aminomethyl triethoxysilane, N, N- di ethyl aminomethyl triethoxysilane, N, N- di -n-propyl aminomethyl triethoxysilane, N, N-di-n-butyl aminomethyl triethoxysilane, N-n-butyl aminomethyl triethoxysilane, N-butan-2-ylaminomethyl triethoxysilane, N- cyclopentyl aminomethyl triethoxysilane, N- cyclohexyl aminomethyl triethoxysilane, N, N- dimethylaminomethyl trimethoxysilane, N, N- diethylaminomethyl trimethoxysilane, N, N- di -n-propyl aminomethyl trimethoxysilane, N, N-di-n-butyl aminomethyl trimethoxysilane, N-n-butyl aminomethyl trimethoxysilane, N-butan-2-ylaminomethyl trimethoxysilane, N- cyclopentyl aminomethyl trimethoxysilane, N-cyclohexylaminomethyltrimethoxysilane, and partial hydrolysates of these. Specifically, the component (B) is preferably

N, N- dimethyl aminomethyl triethoxysilane, N, N- di ethyl aminomethyl triethoxysilane, N, N- di -n-propyl aminomethyl triethoxysilane, N, N-di-n-butyl aminomethyl triethoxysilane, N- cyclopentyl aminomethyl triethoxysilane, N-cyclohexylaminomethyltriethoxysilane, or a partial hydrolysate thereof. The component (B) is particularly preferably

N, N- di ethyl aminomethyl triethoxysilane, N, N-di-n-butyl aminomethyl triethoxysilane, N-cyclohexylaminomethyltriethoxysilane, or a partial hydrolysate thereof.

[0054] If the component (B) takes the form of a partial hydrolysate of the silane represented by the formula (1) , the component (B) is preferably a partial hydrolysate having 2 to 10 silicon atoms.

[0055] The content of the component (B) in the crosslinkable composition according to the present invention may be 5 parts by mass or more and 20 parts by mass or less, is preferably 5 parts by mass or more and 15 parts by mass or less, and even more preferably 5 parts by mass or more and 10 parts by mass or less, relative to 100 parts by mass of the total amount of the components (A) - (I) and (A) - (II) .

The component (B) contributes to the cross-linking reaction with the components (A) - (II) , (C) , and (D) to form a matrix. The component (B) being included in an amount falling within the above-mentioned range can thus maintain the crosslinking density to be within a suitable range and is capable of forming a coating layer having a sufficient hardness. In addition to this, the component (B) being included in such an amount can maintain good removability of the paint while maintaining good adhesion between the substrate and the coating layer.

[0056] Component (C) ) :

The component (C) , which is an alkoxysilane, is a component that is incorporated by being cross-linked into the matrix that is formed by the cross-linkable composition so as to enhance the hardness of the coating layer and maintain a reduced bleed amount of the component (A) - (I) to the surface of the coating layer.

A low viscosity of the component (C) can lower the viscosity of the cross-linkable composition as a whole, and the workability when the cross-linkable composition is applied to a substrate is improved. The composition including the component (C) can be uniformly applied, without resulting in unevenness, to a substrate, and a smooth coating layer can thus be obtained after curing.

[0057] The component (C) is an alkoxysilane represented by the following formula (2) and preferably has no nitrogen atom: R²¹4-xSi (OR²²) _x (2)

R²²s, which may be the same as or different from each other, each represent an optionally substituted monovalent hydrocarbon group having 1 to 5 carbon atoms, with x being 2, 3, or 4 ) .

[0058] The groups R²¹ (when x is 2) are independently determined, and examples of the group R²¹ include an alkyl group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a 1 -n-butyl group, a 2 -n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a hexyl group such as an n-hexyl group, a heptyl group such as an n-heptyl group, an octyl group such as an n-octyl group and an iso-octyl group including a 2 , 2 , 4 -trimethylpentyl group, a nonyl group such as an n-nonyl group, a decyl group such as an n-decyl group, a dodecyl group such as an n-dodecyl group, and an octadecyl group such as an n-octadecyl group, a cycloalkyl group such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a methylcyclohexyl group, an alkenyl group such as a 1 -propenyl group and a 2 -propenyl group, an aryl group such as a phenyl group, a naphthyl group, an anthryl group, and a phenanthryl group, an arkaryl group such as an o-tolyl group, an m-tolyl group, a p-tolyl group, a xylyl group, and an ethylphenyl group, and an aralkyl group such as a benzyl group, an a-phenylethyl group, and a 0- phenylethyl group .

[ 0059 ] When R²¹ is a substituted group and x is 2 , the groups R²¹ are each independently determined, and examples of the group R²¹ include a haloalkyl group such as a 3 , 3 , 3- tri f luoroprop- l-yl group, a 1 , 1 , 1 , 3 , 3 , 3-hexaf luoroprop-2-yl group, and a heptaf luoroprop-2-yl group .

[ 0060 ] The group R²¹ is preferably an unsubstituted linear or branched alkyl having 1 to 6 carbon atoms or a phenyl group , and particularly preferably a methyl , ethyl , vinyl , n- pentyl or n-hexyl group . When the group R²¹ has 6 or less carbon atoms , a coating layer having an adequate hardness can be obtained .

The group R²¹ is preferably a non-aromatic hydrocarbon group because the removability is further improved .

[ 0061 ] The groups R²² are each a group defined for the group R .

The groups R²² are preferably each independently an alkyl group having 1 to 6 carbon atoms , particularly preferably a methyl or ethyl group, and most preferably an ethyl group.

[0062] In the formula (2) , x represents 2, 3, or 4, preferably 3 or 4, and even more preferably 4. When x is 3 or more, the hardness of the obtained coating layer is more suitable. For example, when x is 3 or more, the Shore A hardness of the obtained coating layer can be 30 or more, and when x is 4 or more, the Shore A hardness can be 40 or more. [0063] Examples of the component (C) include tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane, tetra-n-butoxysilane, tetra-i- butoxysilane, tetra-t-butoxysilane, methyltrimethoxysilane, methyl triethoxysilane, ethyl trimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n- propyltriethoxysilane, n-propyltri-n-propoxysilane, n- butyltrimetoxysilane, and n-butyltrimetriethoxysilane .

[0064] The blending amount of the component (C) may be 10 parts by mass or more and less than 200 parts by mass, more preferably 15 parts by mass or more and 150 parts by mass or less, and even more preferably 20 parts by mass or more and 100 parts by mass or less, relative to 100 parts by mass of the total amount of the components (A) - (I) and (A) - (II) .

When the component (C) is included in an amount falling within the above-mentioned range, it is possible to set the hardness of the obtained coating layer to a suitable range (for example, the Shore A hardness is 30 or more and 60 or less) , and to set the bleed amount of the component (A) - (I) to the surface of the coating layer to a suitable range. [0065] Component D:

The component (D) , which is an organosilicon compound, is a catalyst for the cross-linking reaction of the crosslinkable composition and also serves as a reactive catalyst which is incorporated into a matrix formed by the crosslinking reaction to form a coating layer. The component (D) also has the function of enhancing the adhesion of the coating layer to a substrate. In the cross-linkable composition of the present invention, a catalyst other than the component (D) can be used in combination as a catalyst, but it is desirable not to use a catalyst containing a metal from the viewpoint of environment and safety.

[0066] The component (D) is an organosilicon compound including a unit represented by the following formula (3) , in which at least one group D is present per molecule, and at least one group D has an NH2 group,

DfSi (OR³²) eR³¹dO ( 4-d-e-f ) /2 (3)

D(s) , which may be the same as or different from each other, represents a monovalent SiC-bonded group having at least one nitrogen atom not bonded to a carbonyl group (C=O) , d is 0 or 1, e is 0, 1, 2, or 3, f is 0 or 1, and the sum of d, e, and f is 4 or less) .

[0067] The component (D) in the present invention may be any compound selected from the group consisting of a silane, i.e., a compound represented by the formula (3) in which d + e + f = 4 and a siloxane, i.e., a compound including a unit represented by the formula (3) in which d + e + f < 3. The component (D) is preferably a silane.

More preferably, the component (D) in the present invention is a silane having at least one alkoxy group. [0068] Example of the group D include the groups represented by the following formulas: H2NCH2-, H2N(CH2)3-, H₂N(CH₂) 2NH (CH₂) 3-, H₂N(CH₂) 2NH (CH₂) 3NH (CH₂) 3-, H3CNH (CH₂) 3-, C₂H₅NH (CH₂) 3-, H₂N(CH₂)₄-, H₂N(CH₂)₅-, H (NHCH₂CH₂) ₂- (CH₂) 3-, C4H9NH (CH₂) ₂NH (CH₂) 3-, cyclo-CeHnNH (CH₂) 3-, ( CH₃ ) ₂N ( CH₂ ) 3- , and (C₂H₅)₂N(CH₂)₃-.

[0069] The group D is preferably a H₂N(CH₂)3- group, a

H₂N(CH₂) ₂NH (CH₂) 3- group, a H₃CNH(CH₂)₃- group, a C₂H₅NH (CH₂) 3- group, or a cyclo-CeHnNH (CH₂) 3- group, more preferably a H₂N (CH₂) ₂NH (CH₂) 3- group, or a cyclo-CeHnNH (CH₂) 3-group, and particularly preferably a H₂N (CH₂) ₂NH (CH₂) 3- group.

[0070] Examples of the component (D) , i.e., organosilicon compounds include 3-aminopropyltrimethoxysilane, 3- (2- aminoethyl) aminopropyltrimethoxysilane, 3- aminopropyltriethoxysilane, 3- (2- aminoethyl) aminopropyltriethoxysilane, 3- aminopropyldimethoxymethylsilane, 3- (2- aminoethyl) aminopropyldiethoxymethylsilane, 3- aminopropyl diethoxymethyl si lane, 3- aminopropyl (methyl ) silsesquioxane, ethoxy-terminated (CAS No. 128446-60-6) , poly [3- (2-aminoethyl ) aminopropyl ] methylsiloxane, hydroxy-terminated (CAS No. 106214-80-6) , and a 3— (2— aminoethyl ) aminopropylsiloxane-dimethylsiloxane copolymer (CAS No. 67923-07-3) .

[0071] The component (D) is preferably 3- aminopropyltriethoxysilane, 3- (2- aminoethyl) aminopropyltrimethoxysilane, 3- (2- aminoethyl) aminopropyldiethoxymethylsilane, 3- aminopropyl (methyl ) silsesquioxane, ethoxy-terminated (CAS No. 128446-60-6) , or a 3- (2-aminoethyl ) aminopropylsiloxanedimethylsiloxane copolymer (CAS No. 67923-07-3) . The component (D) is particularly preferably 3- (2- aminoethyl) aminopropyltrimethoxysilane, 3- aminopropyl (methyl ) silsesquioxane, ethoxy-terminated (CAS No. 128446-60-6) , or a 3- (2-aminoethyl ) aminopropylsiloxanedimethylsiloxane copolymer (CAS No. 67923-07-3) .

[0072] The number of amino groups in the component (D) is not particularly limited as long as the component contains at least one amino group. When the component (D) contains two or more amino groups, the adhesion strength between the substrate and the coating layer tends to be further enhanced.

[0073] The content of the component (D) in the crosslinkable composition according to the present invention may be 0.1 parts by mass or more and 2 parts by mass or less, preferably 0.1 parts by mass or more and 1.5 parts by mass or less, and more preferably 0.1 parts by mass or more and 1.0 part by mass or less, relative to 100 parts by mass of the total amount of the components (A) - (I) and (A) - (II) .

If the amount is not less than 0.1 parts by mass, the hydrolysis and condensation reactions of the cross-linkable composition (containing the components (A) - (I) and (A) - (II) ) can be accelerated. On the other hand, when the content is less than 0.1 parts by mass, the effect of catalyzing the hydrolysis and condensation reactions decreases, and at the same time, the adhesion decreases. In addition, when the component (D) is blended in an amount exceeding 2 parts by mass and the cross-linkable composition of the present invention is a moisture-curable composition, hydrolysis and condensation reactions may proceed during storage of the moisture-curable composition, and storage stability may deteriorate, such as gelation and curing occur during storage. [0074] The component (D) , i.e., an organosilicon compound, used in accordance with the present invention is already known and can be prepared by methods common in chemistry. The commercially available component (D) is available from WACKER Chemie AG, Munich, Germany under the name GENIOSIL (registered trademark) GF91, GENIOSIL (registered trademark) GF93, GENIOSIL (registered trademark) GF94, GENIOSIL (registered trademark) GF95, GENIOSIL (registered trademark) GF96, WACKER HAFTVERMITTLER AMS60, and WACKER HAFTVERMITTLER AMS70. [0075] In addition to the above-mentioned components (A) -

(I) , (A) - (II) , (B) , (C) , and (D) , the cross-linkable composition according to the present invention may further include any material which has been conventionally used in compositions which can be cross-linked by condensation reaction. Examples of the materials may include an organosiloxane as a component (E) , a filler as a component (F) , an organic solvent as a component (G) , a plasticizer as a component (H) , a catalyst as a component (I) , and a pigment as a component (J) .

[0076] Preferably, the cross-linkable composition according to the present invention does not include any additional component other than the components (A) - (I) to (J) . [0077] Component (E) :

The component (E) , which can optionally be blended, is a component that contributes to the hardness enhancement of the coating layer.

The component (E) is an organosiloxane which contains two to 30 units represented by the following formula (4) . The component (E) contains at least one unit of the formula (4) , in which b is not 0, per molecule.

R⁶a ( R⁷o ) bS i 0 ( 4-a-b ) /2 (4)

(in the formula (4) , R⁶(s) , which may be the same as or different from each other, represents a monovalent SiC-bonded hydrocarbon group, optionally substituted with a halogen atom, or an Si-bonded halogen atom,

R⁷(s) , which may be the same as or different from each other, represents an optionally substituted monovalent hydrocarbon group, a is 0 or 1, b is 0, 1, 2, or 3, and a + b < 4 ) .

[0078] The component (E) used in the present invention is already known and commercially available, for example, under the name WACKER (registered trademark) TES40 from WACKER Chemi e AG.

[0079] Examples of the component (E) include:

(MeSiO3/2) o.37 (MeSi (OEt) O2/2) o.46 (MeSi (OEt) 2O1/2) 0.17 (wherein Mw = 2,400 g/mol, Mn = 900 g/mol, and Mw/Mn = 2.7) , (MeSiC>3/2) o.38 (MeSi (OEt) O2/2) o.46 (MeSi (OEt) 2O1/2) 0.15 (Me2SiC>2/2) 0.

01 (wherein Mw = 2,800 g/mol, Mn = 1,000 g/mol, and Mw/Mn = 2.8) ,

(MeS10>3/2) 0.30 (MeSi (OMe) O2/2) 0.47 (MeSi (OMe) 2O1/2) 0.23 (wherein

Mw = 2,300 g/mol, Mn = 600 g/mol, Mw/Mn = 3.8) , (MeSiC>3/2) 0.32 (MeSi (OMe) O2/2) o.48 (MeSi (OMe) 2O1/2) 0.20 (wherein

Mw = 3,300 g/mol, Mn = 900 g/mol, and Mw/Mn = 3.7)

(Si (OEt) 2O2/2) 0.42 (Si (OEt) O3/2) 0.19 (Si (OEt) 3O1/2) 0.39 (wherein

Mw = 1,000 g/mol, Mn = 800 g/mol, and Mw/Mn = 1.2)

(Si (OEt) 2O2/2) o.48 (Si (OEt) O3/2) 0.35 (Si (OEt) 3O1/2) 0.09 (S1O4/2) o.os (wherein Mw = 1,400 g/mol, Mn = 900 g/mol, and Mw/Mn = 1.6) , (iso-OctSi (OMe) O2/2) 0.09 ( iso-0ctSi03/2 ) o.oe (iso-

OctSi (OMe) 2O1/2) o.os (MeSiO3/2) 0.23 (MeSi (OMe) O2/2) 0.35 (MeSi (OMe) 2O1/2) 0.1 9 (wherein Mw = 1,400 g/mol, Mn = 600 g/mol, and Mw/Mn = 2.3) , and

(iso-OctSi (OMe) O2/2) 0.12 ( iso-0ctSi03/2 ) 0.05 (iso-

OctSi (OMe) 2O1/2) o.os (MeSiO3/2) 0.22 (MeSi (OMe) O2/2) 0.33 (MeSi (OMe) 2O1/2) 0.2 0 (wherein Mw = 1, 600 g/mol, Mn = 700 g/mol, and Mw/Mn = 2.3) . In the formulas, Me represents a methyl group, Et represents an ethyl group, and iso-Oct represents a 2 , 4 , 4-trimethylpentyl group .

[0080] The component (E) is preferably a group represented by the formula (4) wherein R⁶ is a methyl group (Me) , R⁷ is an ethyl group (Et) , a is 0 or 1 and b is 1, 2 or 3. Examples thereof include:

(MeSiO3/2) 0.37 (MeSi (OEt) O2/2) o.46 (MeSi (OEt) 2O1/2) 0.17 (wherein

Mw = 2,400 g/mol, Mn = 900 g/mol, and Mw/Mn = 2.7) , (MeSiO3/2) o.38 (MeSi (OEt) O2/2) o.46 (MeSi (OEt) 2O1/2) 0.15 (Me2SiO2/2) 0.

01 (wherein Mw = 2,800 g/mol, Mn = 1,000 g/mol, and Mw/Mn = 2.8) ,

(MeSiOs/2) 0.30 (MeSi (OMe) O2/2) 0.47 (MeSi (OMe) 2O1/2) 0.23 (wherein

Mw = 2,300 g/mol, Mn = 600 g/mol, and Mw/Mn = 3.8) , (MeSiOs/2) 0.32 (MeSi (OMe) O2/2) o.48 (MeSi (OMe) 2O1/2) 0.20 (wherein

Mw = 3,300 g/mol, Mn = 900 g/mol, and Mw/Mn = 3.7) , (Si (OEt) 2O2/2) 0.42 (Si (OEt) O3/2) 0.19 (Si (OEt) 3O1/2) 0.39 (wherein Mw = 1,000 g/mol, Mn = 800 g/mol, and Mw/Mn = 1.2) , and

(Si (OEt) 2O2/2) o.48 (Si (OEt) O3/2) 0.35 (Si (OEt) 3O1/2) 0.09 (S1O4/2) o.os (wherein Mw = 1,400 g/mol, Mn = 900 g/mol, and Mw/Mn = 1.6) . The component (E) is particularly preferably a group represented by the formula (4) wherein R⁷ is Et and a is 0. Examples thereof include:

(Si (OEt) 2O2/2) 0.42 (Si (OEt) O3/2) 0.19 (Si (OEt) 3O1/2) 0.39 (wherein Mw = 1,000 g/mol, Mn = 800 g/mol, and Mw/Mn = 1.2) , and

(Si (OEt) 2O2/2) o.48 (Si (OEt) O3/2) 0.35 (Si (OEt) 3O1/2) 0.09 (S1O4/2) o.os (wherein Mw = 1,400 g/mol, Mn = 900 g/mol, and Mw/Mn = 1.6) . [0081] The component (E) has a weight-average molar mass

Mw of preferably 500 to 10,000 g/mol, particularly preferably 500 to 8,000 g/mol. [0082] The component (E) has a number-average molar mass

Mn of preferably 200 to 5,000 g/mol, particularly preferably 200 to 3,000 g/mol. [0083] The component (E) has a polydispersity Mw/Mn of preferably 1 to 5, particularly preferably 1 to 4. [0084] In the present invention, the weight-average molar mass Mw and the number-average molar mass Mn, rounded to the nearest hundred, according to DIN 1333:1992-02, paragraph 4, are determined by gel permeation chromatography (GPC) or size exclusion chromatography (SEC) according to DIN 55672-1 using a polystyrene standard and a differential refractive index detector (RI detector) . Unless otherwise stated, THE is used as an eluent for phenyl-containing components and toluene as an eluent for non-phenyl-containing components. The analysis is performed at a column temperature of 45°C. The polydispersity is represented by the quotient Mw/Mn. [0085] The component (E) is preferably a liquid at 25°C and 1,000 hPa . [0086] The content of the component (E) in the crosslinkable composition according to the present invention may be 0 parts by mass or more and 40 parts by mass or less, preferably 1 part by mass or more and 20 parts by mass or less, and more preferably 4 parts by mass or more and 10 parts by mass or less, relative to 100 parts by mass of the total amount of the components (A) - (I) and (A) - (II) .

When the component (E) is included within the above- mentioned range, the viscosity of the cross-linkable composition can be made within a range suitable for application of the composition to a substrate, and the workability is good.

The addition of the component (C) can lower the viscosity of the cross-linkable composition, and obtain a coating layer with a smooth surface. In addition, the component (E) is used together to coexist therein, it is possible to enhance the hardness of the coating layer while suppressing a significant increase in the viscosity of the cross-linkable composition. [0087] Component (F) :

The component (F) , which can optionally be blended, is a filler. The component (F) functions as an anti-sagging agent for the cross-linkable composition.

[0088] Examples of the optionally added component (F) include a reinforcing filler such as carbon black and silica. As the component (F) , silica is preferable, and fumed silica is particularly preferable.

[0089] The component (F) , i.e., silica used according to the present invention may be surf ace-treated . In particular, the fumed silica used as the component (F) is surface-modified with a trimethylsiloxy group.

[0090] In a case where the cross-linkable composition according to the present invention includes the component (F) , the content of the component (F) may be 0 parts by mass or more and 30 parts by mass or less, preferably 5 parts by mass or more and 30 parts by mass or less, and more preferably 8 parts by mass or more and 15 parts by mass or less, relative to 100 parts by mass of the total amount of the components (A) - (I) component and the (A) - (II) . The cross-linkable composition according to the present invention preferably includes the component (F) .

[0091] Component (G) :

The component (G) , which can optionally be blended, is an organic solvent. [0092] Examples of the optional component (G) include saturated hydrocarbons having 6 to 20 carbon atoms, which may be linear, branched, or cyclic, such as mixed hydrocarbon mixtures of CAS number 64742-47-8.

[0093] The optional component (G) is preferably a hydrocarbon mixture of saturated hydrocarbons having 6 to 20 carbon atoms, selected from branched compounds and cyclic compounds .

[0094] The component (G) is preferably a liquid at 25°C and 1,000 hPa .

[0095] The component (G) preferably has an initial boiling point (IBP) (ASTM D86) in the temperature range of 90°C to 270°C and a dry point (DP) (ASTM D86) in the temperature range of 100°C to 310°C.

[0096] The optional component (G) has a density at 15.6°C in the range of 0.699 to 0.831 g/cm³ (EN ISO12185) .

[0097] The optional component (G) preferably has a kinetic viscosity at 40°C of 0.5 mm²/s to 8 mm²/s, particularly preferably 2 mm²/s to 5 mm²/s (ASTM D445) .

[0098] In a case where the cross-linkable composition according to the present invention includes the component (G) , the content of the component (G) may be 0 parts by mass or more and 40 parts by mass or less, preferably 5 parts by mass or more and 30 parts by mass or less, and more preferably 10 parts by mass or more and 20 parts by mass or less, relative to 100 parts by mass of the total amount of the components (A) - (I) and (A) - (II) . The cross-linkable composition according to the invention preferably contains the component (G) .

[0099] Component (H) : The component (H) , which can be optionally blended, is a plasticizer .

[0100] The optional component (H) is preferably a diorganyl-polysiloxane whose terminals are blocked with a triorganylsiloxy group, particularly preferably a dimethylpolysiloxane whose terminals are blocked with a trimethylsiloxy group.

[0101] The component (H) is preferably a liquid at 25°C and 1,000 hPa .

[0102] In particular, the component (H) is a dimethylpolysiloxane whose terminals are blocked with a trimethylsiloxy group and which is a liquid at 25°C and 1,000 hPa .

[0103] The component (H) preferably has a viscosity at

25°C of 5 to 1000 mPa-s, and particularly preferably 35 to 100 mPa-s .

[0104] In a case where the cross-linkable composition according to the present invention includes the component (H) , the content of the component (H) may be 0 parts by mass or more and 20 parts by mass or less, preferably 5 parts by mass or more and 20 parts by mass or less, and more preferably 5 parts by mass or more and 10 parts by mass or less, relative to 100 parts by mass of the total amount of the components (A) - (I) and (A) - (II) .

[0105] Component (I) :

The component (I) , which can be optionally blended, is a catalyst .

[0106] The optional component (I) , i.e., the optional catalyst is any compound conventionally used in moisture curing systems, and examples of such a catalyst include a diorganotin compound, a titanium alkoxylate, a titanium chelate, zinc 2-ethylhexanoate, and bismuth (III) 2- ethylhexanoate .

[0107] It is preferable that the cross-linkable composition according to the invention preferably do not contain any metal-containing catalyst (I) . Furthermore, it is particularly preferable that the cross-linkable composition according to the invention do not contain any catalyst (I) . [0108] Component (J) :

The component (J) , which can be optionally blended, is a pigment . [0109] Examples of the optional component (J) include inorganic pigments such as titanium dioxide and yellow, red and black iron oxide pigments . [0110] In a case where the cross-linkable composition according to the present invention includes the component (J) , the content of the component (J) may be 0 parts by mass or more and 2 parts by mass or less, preferably 0.5 parts by mass or more and 2.0 parts by mass or less, relative to 100 parts by mass of the total amount of the components (A) - (I) and (A) - (ID • [0111] The viscosity of the cross-linkable composition, which is the final product containing the components (A) - (I) to (D) and optional components as required, is not particularly limited, and is preferably, for example, in the range of 1, 000 mPa-s or more and 5, 000mPa-s or less. When the viscosity falls within the above-mentioned range, the workability when the cross-linkable composition is applied to a substrate is good, and a smooth coating layer can be obtained after the cross-linkable composition is cured. [0112] The present invention also provides a crosslinkable composition including: relative to 100 parts by mass of the total amount of the components (A) - (I) and (A) - (II) , the component (B) in an amount of 5 parts by mass or more and 20 parts by mass or less, the component (C) in an amount of 10 parts by mass or more and 200 parts by mass or less, the component (D) in an amount of 0.1 parts by mass or more and 2 parts by mass or less, optionally, the component (E) in an amount of 0 parts by mass or more and 40 parts by mass or less, optionally, the component (F) in an amount of 0 parts by mass or more and 30 parts by mass or less, and optionally, the component (G) , i.e., an organic solvent in an amount of 0 parts by mass or more and 40 parts by mass or less.

[0113] The cross-linkable composition of the present invention is a moisture-curable composition, and may be a multi component composition such as two or more component composition, or can be a one component composition. When the cross-linkable composition is used as a moisture-curable coating agent for obtaining a coating layer by applying the composition to a substrate, the cross-linkable composition is particularly preferably a one component composition, which does not require a mixing work during application.

[0114] A method for producing the cross-linkable composition of the present invention that is used as a one component moisture-curable coating agent is not particularly limited, and the cross-linkable composition may be produced by mixing individual components in any order.

Furthermore, a method for producing the cross-linkable composition of the present invention preferably includes: a first mixing step of blending the component (A) - (I) into a mixture of the component (A) - (II) and the component (B) ; a second mixing step of blending the component (C) into the mixture obtained in the first mixing step; and a third mixing step of blending the component (D) into the mixture obtained in the second mixing step.

[0115] First mixing step:

The component (A) - (II) used in the first mixing step of the above-mentioned method for producing the cross-linkable composition can be obtained by a known method of mixing a diorganopolysiloxane having silanol groups at respective terminals of the molecular chain and an excessive amount of the component (B) , and causing a dealcoholization reaction.

In the first mixing step, the component (A) - (I) is introduced into the mixture of the unreacted component (B) and the component (A) - (II) obtained as described above and mixed. The temperature during mixing is not particularly limited, and it can be 0°C or higher and 80°C or lower, preferably 20°C or higher and 50°C or lower.

In a case where the cross-linkable composition includes the filler (F) , the filler (F) may be blended together with the component (A) - (II) in the first mixing step. When the filler (F) is included, it is preferable that mixing be performed by a mixing method with a high shear force applied, for example, using a dissolver mixer or the like.

If the component (F) is introduced before the other liquid components ( (A) - (I) , (B) , (C) , (D) , etc.) are introduced, the viscosity of the mixture increases, and a shear force is easily applied. Thus, the dispersibility of the component (F) in the cross-linkable composition is improved .

When the component (F) is included, the viscosity of the mixture after blending the component (F) , i.e., the mixture of the component (A) - (I) , the component (A) - (II) , the component (B) , and the component (F) is preferably 10,000 mPa-s or more and 100,000 mPa-s or less for obtaining good dispersibility, and more preferably 2,000 mPa-s or more and 50, 000 mPa-s or less .

[0116] Second mixing step:

The second mixing step in the above-mentioned method for producing the cross-linkable composition is a step of introducing and mixing the component (C) into the mixture obtained in the first mixing step. The temperature during mixing is not particularly limited, and it can be 0°C or higher and 80°C or lower, preferably 20°C or higher and 50°C or lower.

In a case where the cross-linkable composition includes the component (E) , the component (E) may be blended together with the component ( C ) in the second mixing step . [ 0117 ] Third mixing step :

The third mixing step in the above-mentioned method for producing the cross-linkable composition is a step of introducing and mixing the component ( D) into the mixture obtained in the second mixing step . The temperature during mixing is not particularly limited, and it can be 0°C or higher and 80°C or lower, preferably 20°C or higher and 50°C or lower . I f the mixture is placed in an environment containing moisture , the cross-linking reaction proceeds after the component ( D) is blended . Thus , after the component ( D) is introduced in the third mixing step, the mixture is preferably stored in a nitrogen atmosphere or under reduced pressure . [ 0118 ] The cross-linkable composition of the present invention has storage stability in a temperature range of 20°C or higher and 40°C or lower in the absence of water, and the cross-linkable composition undergoes a cross-linking reaction upon contact with water .

[ 0119 ] The present invention further provides a method for producing a coating layer including : an application step of applying the above-mentioned cross-linkable composition to a substrate ; and a curing step of moisture-curing the cross-linkable composition applied in the application step .

Speci fic examples of the application method in the application step include an application method to the surface of a substrate by a general and conventionally known application method such as painting, blowing, scraping, rolling, spraying, brushing, pouring, spatula coating, dipping, or roller coating . [ 0120 ] In the method of the present invention, the application amount of the cross-linkable composition is 50 g or more and 400 g or less , preferably 70 g or more and 200 g or less , per square meter of a substrate surface area . The application amount can be 50 g or more and 200 g or less for a smooth substrate such as a metal substrate, and it may be 100 g or more and 400 g or less for a porous substrate such as wood .

[0121] The substrate to which the cross-linkable composition is applied is not particularly limited, and examples of the substrate include a cement-based material, a gypsum board, asphalt, wood, metal, a resin, a tile, glass, a natural stone, an artificial stone, and a combination thereof.

These substrates may be pre-treated with a primer.

[0122] Examples of the metal used as the substrate include iron, aluminum, titanium, copper, and an alloy containing these. The metal may be treated by electrodeposition coating or the like.

Examples of metal oxides used as the substrate include a silicon oxide, an aluminum oxide, a zirconium oxide, a titanium oxide, and mixtures of these metal oxides.

[0123] Examples of the cement-based material used as the substrate include concrete, mortar, a siding board, ALC (light aerated concrete) , a slate board, a calcium silicate board, and a woody cement board, .

[0124] Examples of the wood used as the substrate include solid natural wood, and a wood product such as a chipboard made from wood, a board made of wood chips, plywood, a laminate board, and veneer. Examples of the solid natural wood include fir, spruce, alder, beech, pine, oak, poplar, linden, willow, maple, cedar, birch, Hevea brasiliensia, cherry, larch, juniper, yew, black locust, elm, walnut, mahogany, rosewood, teak, Borneo teak, pencil cedar, and olive, without being limited thereto.

[0125] As the resin used as the substrate, for example, the type is not particularly limited, and examples of the resin include a synthetic resin such as an acrylic resin, an acrylic urethane resin, an acrylic silicone resin, a urethane resin, an alkyd resin, an amino resin, an unsaturated polyester resin, an epoxy resin, a vinyl butyral resin, and a vinyl chloride resin.

[0126] The coating layer obtained by curing the crosslinkable composition of the present invention has a suitable hardness (e.g., a Shore A hardness of 30 or more and 60 or less) . Here, while the coating layer has the hardness, it also has flexibility. Thus, it is possible to obtain a coating layer that favorably adheres to a stretchable material such as wood, and that hardly cracks or peels off after curing .

[0127] It is also possible to further apply (overcoat) the cross-linkable composition before curing to the surface of the coating layer that has been obtained by applying and curing the cross-linkable composition on the substrate surface by the above-mentioned method. That is, when cracks, chips, scratches, or the like occur in the coating layer due to aged deterioration, physical impact, or the like, the coating layer can be repaired by applying the cross-linkable composition.

The surface of the coating layer has good paintability, and even when the cross-linkable composition is overcoated on the surface of the coating layer, overcoating can be performed without causing cissings. The cross-linkable composition after overcoating forms a cured product with the same chemical composition as the coating layer before overcoating by moisture curing. Thus, the new coating layer adheres well to the previous coating layer before overcoating, and it is less likely to be peeled off with high-pressure washing water or the like. Thus, the new coating layer obtained after overcoating can also exhibit good repeated paintability and repeated removability while maintaining its hardness.

[0128] The cross-linkable composition may contain any one or two or more selected from the group consisting of octamethylcyclotetrasiloxane (D4) , decamethylcyclopentasiloxane (D5) , dodecamethylcyclohexasiloxane (D6) , tetradecamethylcycloheptasiloxane (D7) , and hexadecamethylcyclooctasiloxane (D8) .

The total content of (D4) , (D5) , (D6) , (D7) , and (D8) may be less than 0.1 parts by mass (i.e., less than 1,000 ppm) relative to 100 parts by mass of the entire amount of the cross-linkable composition.

When the total content of (D4) to (D8) contained in the cross-linkable composition falls within the aforementioned range, the flashing point of the whole composition may be increased, and safety during storage may be improved.

A cross-linkable composition containing (D4) to (D8) in an amount of less than 0.1 parts by mass as the total content of (D4) to (D8) relative to 100 parts by mass of the total amount of the cross-linkable composition can be produced by using the components (A) - (I) and (A) - (II) in which the total content xA of (D4) to (D8) is less than 0.1 parts by mass, the component (B) in which the total content xB of (D4) to (D8) is less than 0.1 parts by mass, and the component (C) in which the total content xC of (D4) to (D8) is less than 0.1 parts by mass such that the total content Xa + xB + xC is less than 0.1 parts by mass .

The respective contents of (D4) to (D8) are measured by gas chromatography. The measurement condition of gas chromatography may be appropriately selected in accordance with a conventionally known method. [0129] As a method for reducing the contents of (D4) to (D8) in the cross-linkable composition, a method of subjecting each component to a heating treatment under reduced pressure is widely known. For example, it is preferable that a heating treatment under reduced pressure be performed at 180°C and 20 mmHg for about 8 hours during production of each of or all raw materials for the components (A) - (I) to (D) .

[0130] The cross-linkable composition of the present invention may include an optional component in addition to the above-described components as long as the object of the present invention is achieved. For example, any other materials, such as a defoamer, a cure rate modifier, additives, and the like can be included.

[0131] The present invention further provides a crosslinkable composition characterized in that the cross-linkable composition includes the above-mentioned components (A) - (I) , (A) - (II) , (B) , (C) , and (D) , and blending 10 parts by mass or more and 200 parts by mass or less of the component (C) relative to 100 parts by mass of the total amount of the components (A) - (I) and (A) - (II) improves the repeated paintability and enhances hardness of the cured product of the cross-linkable composition.

[0132] The repeated paintability of the cured product described herein can be evaluated by the following evaluation method .

Repeated paintability evaluation method:

On the surface of the coating layer obtained by curing the cross-linkable composition of the present invention, acrylic lacquer spray (brown) manufactured by Nippon Paint Co., Ltd. is sprayed in an area of 30 cm x 20 cm from 30 cm above the surface of the coating layer (before drying, the application amount is 100 g/m²) . After standing for 2 hours, the paint is removed by jetting water against the paint at a distance of 10 cm from the surface of the coating layer using a household high-pressure washer. These processes are repeated 10 times to obtain a surface evaluation test piece for repeated paintability evaluation.

[0133] The present invention also provides a laminate including a substrate and a coating layer obtained by curing the above-mentioned cross-linkable composition. The laminate has a coating layer on the surface that is excellent in repeated paintability and repeated removability . Thus , the laminate is useful as a board that is expected to be used repeatedly . For example , such a board is painted on the surface , and after the paint is viewed for a certain period of time , it is removed with high pressure washing water and replaced with another paint . The laminate can be used, for example , for a steel board installed at a construction site or an outdoor gathering place , a protective fence , an outer surface of a vehicle such as a wrap advertising vehicle , an advertising signboard, an elevated bridge pier surface , an outer wall of a public structure , or the like .

[ 0134 ] The hardness of the cured product can be evaluated by measuring a Shore A hardness with a type A durometer based on the method defined in JIS K 6253 .

Examples

[ 0135 ] The present invention will be speci fically described on the basis of examples and comparative examples as well as respective blending amounts of the components in Tables 1 and 2 and evaluation results , but the present invention is not limited to the following examples .

[ 0136 ] Method for preparing evaluation test piece :

A cross-linkable composition obtained by mixing respective components shown in Tables 1 and 2 was applied to a slate substrate with a roller in an amount of 100 g per square meter of substrate surface area . Then, the applied substrate was allowed to stand for 7 days under conditions of a temperature of 23°C and a humidity of 50% . A cured product ( coating layer ) thus obtained was used as a test piece for evaluation of paintability, repeated paintability, painting retainability, repeated painting retainability, removability, repeated removability, and smoothness .

[ 0137 ] Workability evaluation method :

The viscosity of the cross-linkable composition before curing was measured using a rotational viscometer in a temperature condition of 25°C. In this measurement, the workability was evaluated as good if the viscosity was 1,000 mPa-s or more and 5, 000 mPa-s or less.

[0138] Paintability evaluation method:

On the surface of the evaluation test piece, acrylic lacquer spray (brown) manufactured by Nippon Paint Co., Ltd. is sprayed in an area of 30 cm x 20 cm from 30 cm above the surface of the coating layer, and the presence or absence of cissings is visually inspected.

In the following evaluation criteria, A or B was evaluated as good paintability.

A: No visible cissings

B: More than 0 and less than 10 cissings (with (|) < 2 mm) /m² and no cissing with (|) > 2 mm

E: There are cissings with (|) > 5 mm [0139] Repeated paintability evaluation method:

On the surface of the evaluation test piece, the acrylic lacquer spray (brown) manufactured by Nippon Paint Co., Ltd. is sprayed in an area of 30 cm x 20 cm from 30 cm above the surface of the coating layer (before drying, the application amount is 100 g/m²) . After standing for 2 hours, the paint is removed by jetting against the paint at a distance of 10 cm from the surface of the evaluation test piece using a household high-pressure washer. These processes are repeated 10 times to obtain a surface evaluation test piece for repeated paintability evaluation.

On the surface of the evaluation test piece for repeated paintability evaluation, the acrylic lacquer spray (brown) manufactured by Nippon Paint Co., Ltd. is sprayed in an area of 30 cm x 20 cm from 30 cm above the surface of the coating layer, and the presence or absence of cissings is visually inspected .

In the following evaluation criteria, A or B was evaluated as good repeated paintability .

A: No visible cissings

B : More than 0 and less than 10 cissings (with (|) < 2 mm) /m² and no cissings with (|) > 2 mm

C : 10 or more cissings (with (|) < 2 mm) /m² , more than 0 and less than 10 cissings (with 2 mm < (|) < 5 mm) /m² , and no cissings with (|) > 5 mm

D : 10 or more cissings (with 2 mm < (|) < 5 mm) /m² and no cissings with (|) > 5 mm

E : There are cissings with (|) > 5 mm [ 0140 ] Painting retainability evaluation method :

The evaluation test piece was showered with water at a temperature of 25°C under a condition of 0 . 1 kgf/cm² for 30 minutes from a height of 30 cm . After the test piece was allowed to stand for 2 hours and dried, the surface of the test piece was visually inspected . In the following evaluation criteria, A or B was evaluated as good painting retainability .

A: No visible peeling

B : No visible peeling but a few cracks

C : Visible peeling with peeling area of less than 5% D : Peeling area of 5% or more and less than 30% E : Peeling area of 30% or more

[ 0141 ] Repeated painting retainability evaluation method :

The surface of the evaluation test piece was showered with water at a temperature of 25°C under the condition of 0 . 1 kgf/cm² for 30 minutes from a height of 30 cm, and then the test piece was allowed to stand for 2 hours and dried . After these processes were repeated 10 times , the surface of the test piece was visually inspected . In the following evaluation criteria, A or B was evaluated as good repeated painting retainability . A: No visible peeling

B : No visible peeling but a few cracks

C : Visible peeling with peeling area of more than 0% and less than 5%

D : Peeling area of 5% or more and less than 30%

E : Peeling area of 30% or more

[ 0142 ] Removability evaluation method :

On the surface of the evaluation test piece , the acrylic lacquer spray (brown) manufactured by Nippon Paint Co . , Ltd . was sprayed in an area of 30 cm x 20 cm from 30 cm above the surface of the coating layer (before drying, the application amount was 100 g/m² ) , and the test piece was then allowed to stand for 2 hours . After that , the lacquer was removed by j etting water against the lacquer at a distance of 10 cm from the surface using a high-pressure washer at a pump pressure of 100 bar, and a degree of removal ( residual paints of acrylic lacquer ) was visually evaluated . In the following evaluation criteria, A or B was evaluated as good removability .

A: No residual paints

B : Residual paints of more than 0% and 5% or less

C : Residual paints of more than 5% and 10% or less

D : Residual paints of more than 10% and less than 30%

E : Residual paints of 30% or more

[ 0143 ] Repeated removability evaluation method :

On the surface of the evaluation test piece , the acrylic lacquer spray (brown) manufactured by Nippon Paint Co . , Ltd . was sprayed in an area of 30 cm x 20 cm from 30 cm above the surface of the coating layer (before drying, the application amount was 100 g/m² ) , and the test piece was then allowed to stand for 2 hours . After that , the lacquer was removed by j etting water against the lacquer at a distance of 10 cm from the surface using a high-pressure washer at a pump pressure of 100 bar . These processes were repeated 10 times . Then, the above-mentioned acrylic lacquer spray was sprayed on the surface of the evaluation test piece , and the lacquer was removed by jetting water against the lacquer at a distance of 10 cm from the surface using a high-pressure washer with a pump pressure of 100 bar. Then, a degree of removal (residual paints of lacquer) was visually evaluated. In the following evaluation criteria, A or B was evaluated as good repeated removability .

A: No residual paints

B: Residual paints of more than 0% and 5% or less

C: Residual paints of more than 5% and 10% or less

D: Residual paints of more than 10% and less than 30%

E: Residual paints of 30% or more

[0144] Smoothness evaluation method:

The surface of the evaluation test piece was visually inspected. In the following evaluation criteria, A or B was evaluated as good smoothness.

A: Almost no paint unevenness

B: Some paint unevenness

C: Large amount of paint unevenness

[0145] Touch dry time evaluation method:

Thirty minutes after the film was formed, the film was touched with a finger every hour from 1 hour to 7 hours, and after 24 hours. When it is felt that the film does not stick to the finger at the specified time, it is determined that the touch dry condition has been reached, and that time is taken as the touch dry time.

[0146] Hardness evaluation method of evaluation test piece :

The Shore A hardness of a cured product of a 5 mm-thick sheet was measured according to JIS K 6249. [0147] Example 1:

A fumed silica filler was added as the component (F) to a mixture of a linear polydimethylsiloxane having a viscosity of 5, 240 mPa-s at 25°C and containing an (N,N-di-n- butylaminotriethoxy ) diethoxysilyl group at both terminals as the component (A) - (II) , and an (N,N-di-n- butylaminotriethoxy) triethoxysilane as the component (B) .

Note that the component (A) - (II) included a mixture of two components, one having a viscosity at 25°C of 6,000 mPa-s and the other having a viscosity at 25°C of 2,000 mPa-s, having different numbers of dimethylsiloxy units at a mass ratio of 53.0:40:9.

To the resulting mixture, a linear polydimethylsiloxane having a viscosity of 100 mPa-s and containing a trimethylsilyl group blocked at both terminals was added as the component (A) - (I) . The mixture was stirred at 25°C for 10 minutes at a stirring speed of 400 rpm.

Then, tetraethoxysilane as the component (C) , a tetraethoxysilane oligomeric hydrolysate as the component (E) , and an isoparaffinic solvent as the component (G) were added to the mixture, and the resulting mixture was stirred at 25°C for 5 minutes at a stirring speed of 400 rpm.

Finally, 3- ( 2-aminoethyl ) aminopropyltrimethoxysilane was added as the component (D) , and the mixture was stirred at 25°C for 5 minutes at a stirring speed of 400 rpm. The mixture was then stirred under a pressure of 100 hPa for additional 25 minutes for degassing to obtain a cross-linkable composition according to Example 1. [0148] Here, the fumed silica filler is a fumed silica commercially available as HDK (registered trademark) H2000 from WACKER Chemie AG. The fumed silica has a carbon content of 2.3 to 3.2 wt% (according to DIN ISO10694) and a tap density of 100 to 250 g/1 (according to DIN EN ISO787011) , and has been surface-modified with a trimethylsiloxy group. The BET surface area of the fumed silica before the surface treatment is 190 to 210 m²/g.

The tetraethoxysilane oligomeric hydrolysate is commercially available from WACKER Chemie AG as WACKER (registered trademark) TES40 and has a density of 1.06 to 1.07 g/cm³ at 20°C (DIN51757) , a flash point of 62°C (DIN51755) , and an SiO2 content of about 41%. The isoparaffinic solvent is an organic solvent commercially available from ExxonMobil Chemical as ISOPAR (registered trademark) M. [0149] The obtained cross-linkable composition had a low viscosity of 3,200 mPa-s and good workability, and the coating layer obtained after curing exhibited good smoothness.

The results of the paintability and the repeated paintability were also extremely good. The repeated painting retainability was also good, and the removability and the repeated removability were also extremely good. The Shore A hardness of the coating layer was 52, which was sufficient. [0150] Example 2:

A cross-linkable composition according to Example 2 was obtained in the same manner as that in Example 1 except that the tetraethoxysilane oligomeric hydrolysate as the component (E) was not blended. [0151] The viscosity of the obtained cross-linkable composition was slightly higher than that in Example 1. However, the coating layer obtained after curing exhibited good smoothness. Although the Shore A hardness of the coating layer was lower than that in Example 1, it was within a range for sufficient hardness. [0152] Example 3:

A cross-linkable composition according to Example 3 was obtained in the same manner as that in Example 1 except that methyltriethoxysilane was used as the component (C) instead of tetraethoxysilane . [0153] The evaluation results were almost the same as those of Example 1, but the Shore A hardness of the coating layer was lower than that of Example 1. [0154] Example 4:

A cross-linkable composition according to Example 4 was obtained in the same manner as that in Example 1 except that tetramethoxysilane was used as the component (C) instead of tetraethoxysilane . [0155] The evaluation results were as good as those of

Example 1.

[0156] Example 5:

A cross-linkable composition according to Example 5 was obtained in the same manner as that in Example 1 except that methyltrimethoxysilane was used as the component (C) instead of tetraethoxysilane. [0157] The evaluation results were almost the same as those of Example 1, but the Shore A hardness of the coating layer was lower than that of Example 1.

On the basis of the results of Examples 1, 3, and 5, it was confirmed that addition of the component having four alkoxy groups bonded to a silicon atom (a 4-functional silane) as the component (C) increases the hardness of the coating layer more than addition of the component having three alkoxy groups bonded to a silicon atom (a 3-functional silane) . [0158] Example 6:

A cross-linkable composition according to Example 6 was obtained in the same manner as that in Example 1 except that the amount of tetraethoxysilane used as the component (C) was decreased to approximately a half of the amount in Example 1, and SILRES MSE 100 manufactured by WACKER Chemie AG, which is an oligomer of methyltrimethoxysilane, was further added as the component (E) . [0159] The paintability, repeated paintability, and painting retainability were slightly inferior to those of Example 1. This is believed to be due to the poor compatibility of SILRES MSE 100 with other components in the composition. On the other hand, favorable results as those in Example 1 were obtained in terms of removability and repeated removability . [0160] Example 7:

A cross-linkable composition according to Example 7 was obtained in the same manner as that in Example 1 except that aminopropyltrimethoxysilane was used as the component (D) instead of 3- (2-aminoethyl ) aminopropyltrimethoxysilane . [0161] The same good results as those in Example 1 were obtained except that the viscosity of the cross-linkable composition slightly increased. [0162] Example 8:

A cross-linkable composition according to Example 8 was obtained in the same manner as that in Example 1 except that phenyltriethoxysilane was blended as the component (C) instead of tetraethoxysilane. [0163] The removability and repeated removability slightly decreased but were within the allowable ranges. [0164] Comparative Example 1:

A cross-linkable composition according to Comparative Example 1 was obtained in the same manner as that in Example 1 except that components corresponding to the component (C) and the component (E) were not blended. [0165] Since the component (C) was not included, the viscosity of the cross-linkable composition was high and the workability was poor. Furthermore, the obtained coating layer was observed to be highly uneven, resulting in poor smoothness .

The paintability was very poor, and this is thought to be due to the large amount of the component (A) - (I) bleeding to the surface and causing the paint repelling. After removing the paints 10 times, the repeated paintability was slightly improved, but the results were unsatisfactory. It is thought that, although the paintability was improved from the initial stage as the component (A) - (I) on the surface decreased by removing the paints multiple times, the results were still unsatisfactory.

The results of the painting retainability and the repeated painting retainability were also poor. The hardness of the coating layer was also insufficient.

On the other hand, the removability and the repeated removability were good. [0166] Comparative Example 2:

A cross-linkable composition according to Comparative Example 2 was obtained in the same manner as that in Example 1 except that the component corresponding to the component (C) was not blended but the component (E) was blended. [0167] Compared to the results of Comparative Example 1, the workability, the paintability, the repeated paintability, the painting retainability, the repeated painting retainability, and the hardness of the coating layer were slightly improved. This is thought to be the effect of blending the component (E) . However, these evaluation results were all unsatisfactory. [0168] Comparative Example 3:

A cross-linkable composition according to Comparative Example 3 was obtained in the same manner as that in Example 1 except that the component corresponding to the component (C) was not blended, and a methyltrimethoxysilane oligomer, SILRES MSE 100, manufactured by WACKER Chemie AG was blended as the component (E) instead of the tetraethoxysilane oligomeric hydrolysate . [0169] The result of the smoothness of the obtained coating layer was poor due to the high viscosity of the crosslinkable composition. Furthermore, the results of the removability and the repeated removability were poor. [0170] Comparative Example 4:

A cross-linkable composition according to Comparative Example 4 was obtained in the same manner as that in Example 1 except that isooctyltriethoxysilane was blended as the component (C) instead of tetraethoxysilane. [0171] The obtained coating layer was very soft and lacked hardness, and the painting retainability was slightly reduced. It is assumed that the organic group (isooctyl group) of isooctyltriethoxysilane is bulky, which causes steric hindrance and reduces the crosslink density. [0172] In each of Examples 1 to 8 and Comparative Examples 1 to 4, the touch dry time was 2 hours or longer and 3 hours or shorter.

Furthermore, in Examples 1 to 7, the total content of octamethylcyclotetrasiloxane (D4) , decamethylcyclopentasiloxane (D5) , dodecamethylcyclohexasiloxane (D6) , tetradecamethylcycloheptasiloxane (D7) , and hexadecamethylcyclooctasiloxane (D8) was less than 0.3 parts by mass relative to 100 parts by mass of the entire cross- linkable composition.

[0173] [Table 1]

[0174] Some or all of the above-described embodiments may be described as following appendices, but are not limited to the following description. Each of the appendices can also be combined with each of claims recited in the claim section.

[0175] (Appendix 1)

A cross-linkable composition including: a component (A) - (I) that is a diorganopolysiloxane having a linear or branched structure whose molecular chain terminals are blocked with a triorganosilyl group; a component (A) - (II) that is a diorganopolysiloxane having a linear or branched structure having, per molecule, at least two (R²R³NCH2) groups and at least four (OR⁴) groups (R² represents a hydrogen atom or an optionally substituted monovalent linear or branched hydrocarbon group having 1 to 6 carbon atoms,

R⁴s, which may be the same as or different from each other, each represent an optionally substituted monovalent hydrocarbon group) ; a component (B) that is a silane represented by the following formula (1) and/or a partial hydrolysate thereof, (R²R³NCH₂) Si (OR⁴) ₃ (1) ; a component (C) that is an alkoxysilane represented by the following formula (2) , R²¹4-xSi (OR²²) _x (2)

R²²s, which may be the same as or different from each other, each represent an optionally substituted monovalent hydrocarbon group having 1 to 5 carbon atoms, with x being 2, 3, or 4 ) ; and a component (D) that is an organosilicon compound including a unit represented by the following formula (3) , in which at least one group D is present per molecule, and at least one group D has an NH2 group,

DfSi (OR³²) eR³¹dO ( 4-d-e-f ) /2 (3)

[0176] Appendix 2:

The cross-linkable composition according to Appendix 1, further including a component (E) that is an organosiloxane which contains two to 30 units represented by the following formula (4) , and that contains at least one unit of the formula (4) , in which b is not 0, per molecule:

R⁶a ( R⁷o ) _bS i 0 ( 4-a-b ) /2 (4)

[0177] Appendix 3:

The cross-linkable composition according to Appendix 1 or 2, wherein the group R²² in the component (C) is an ethoxy group .

[0178] Appendix 4:

The cross-linkable composition according to any one of Appendices 1 to 3, wherein the group (R²R³NCH2) in the component (A) - (II) is one selected from the group consisting of an N, N-dimethylaminomethyl group, an N, N-diethylaminomethyl group, an N, N-di-n-propylaminomethyl group, and N,N-di-n butylaminomethyl group. [0179] Appendix 5:

The cross-linkable composition according to any one of Appendices 1 to 4, further including a component (F) that is a filler .

[0180] Appendix 6:

The cross-linkable composition according to any one of Appendices 1 to 5, including: relative to 100 parts by mass of a total amount of the components (A) - (I) and (A) - (II) , the component (B) in an amount of 5 parts by mass or more and 20 parts by mass or less, the component (C) in an amount of 10 parts by mass or more and 200 parts by mass or less, the component (D) in an amount of 0.1 parts by mass or more and 2 parts by mass or less, optionally, the component (E) in an amount of 0 parts by mass or more and 40 parts by mass or less, optionally, the component (F) in an amount of 0 parts by mass or more and 30 parts by mass or less, and optionally, the component (G) , i.e., an organic solvent in an amount of 0 parts by mass or more and 40 parts by mass or less. [0181] Appendix 7:

A one-component moisture-curable coating agent including the cross-linkable composition according to any one of Appendices 1 to 6.

[0182] Appendix 8:

A method for producing the cross-linkable composition according to any one of Appendices 1 to 6, including: a first mixing step of blending the component (A) - (I) into a mixture of the component (A) - (II) and the component (B) ; a second mixing step of blending the component (C) into the mixture obtained in the first mixing step; and a third mixing step of blending the component (D) into the mixture obtained in the second mixing step.

[0183] Appendix 9:

A method for producing a coating layer including: an application step of applying the cross-linkable composition according to any one of Appendices 1 to 6 to a substrate; and a curing step of moisture-curing the cross-linkable composition applied in the application step.

[0184] Appendix 10:

The method according to Appendix 9, wherein the crosslinkable composition is used in an amount of 50 g or more and 400 g or less per square meter of a substrate surface area. [0185] Appendix 11:

A method for repairing a coating layer which is a cured product of the cross-linkable composition according to any one of Appendices 1 to 6, including overcoating the cross-linkable composition according to any one of Appendices 1 to 6 on a surface of the coating layer.

[0186] Appendix 12:

The method according to any one of Appendices 9 and 10, wherein the substrate is one selected from the group consisting of a cement-based material, a gypsum board, asphalt, wood, metal, a resin, a tile, glass, a natural stone, an artificial stone, and a combination thereof.

[0187] Appendix 13:

A cross-linkable composition including the component (A) - (I) , the component (A) - (II) , the component (B) , the component

(C) , and the component (D) , wherein the component (C) is blended in an amount of 10 parts by mass or more and 200 parts by mass or less relative to 100 parts by mass of the total amount of the components (A) - (I) and (A) - (II) , thereby improving repeated paintability and hardness of a cured product of the cross-linkable composition. [0188] Appendix 14:

A laminate including a substrate and a coating layer obtained by curing the above-mentioned cross-linkable composition according to any one of Appendices 1 to 6.

Claims

[Claim 1] A cross-linkable composition comprising: a component (A) - (I) that is a diorganopolysiloxane having a linear or branched structure whose molecular chain terminals are blocked with a triorganosilyl group; a component (A) - (II) that is a diorganopolysiloxane having a linear or branched structure having, per molecule, at least two (R²R³NCH2) groups and at least four (OR⁴) groups

R²¹4-xSi (OR²²) _x (2)

DfSi (OR³²) _eR³¹dO(4-d-e-f)/2 (3)

[Claim 2] The cross-linkable composition according to claim 1, further comprising a component (E) that is an organosiloxane which contains two to 30 units represented by the following formula (4) , and that contains at least one unit of the formula (4) , in which b is not 0, per molecule:

R⁶a ( R⁷o ) _bS i 0 ( 4-a-b ) /2 (4)

R⁷(s) , may be the same as or different from each other, represents an optionally substituted monovalent hydrocarbon group, a is 0 or 1, b is 0, 1, 2, or 3, and a + b < 4 ) . [Claim 3] The cross-linkable composition according to claim 1 or 2, wherein the group R²² in the component (C) is an ethoxy group .

[Claim 4] The cross-linkable composition according to claim 1 or 2, wherein the group (R²R³NCH2) in the component (A) - (IT) is one selected from the group consisting of an N,N- dimethylaminomethyl group, an N, N-diethylaminomethyl group, an N, N-di-n-propylaminomethyl group, and N,N-di-n butylaminomethyl group.

[Claim 5] The cross-linkable composition according to claim 1 or 2, further comprising a component (F) that is a filler.

[Claim 6] The cross-linkable composition according to claim 1 or 2, comprising: relative to 100 parts by mass of a total amount of the components (A) - (I) and (A) - (IT) , the component (B) in an amount of 5 parts by mass or more and 20 parts by mass or less, the component (C) in an amount of 10 parts by mass or more and 200 parts by mass or less, the component (D) in an amount of 0.1 parts by mass or more and 2 parts by mass or less, a component (E) in an amount of 0 parts by mass or more and 40 parts by mass or less, the component (E) being an organosiloxane which contains two to 30 units represented by the following formula (4) , and containing at least one unit of the formula (4) , in which b is not 0, per molecule:

R⁶a ( R⁷O ) bS i 0 ( 4-a-b ) /2 (4)

(in the formula (4) , R⁶(s) , which may be the same as or different from each other, represents a monovalent SiC-bonded hydrocarbon group, optionally substituted with a halogen atom, or an Si-bonded halogen atom, R⁷(s) , which may be the same as or different from each other, represents an optionally substituted monovalent hydrocarbon group, a is 0 or 1, b is 0, 1, 2, or 3, and a + b < 4) , a component (F) that is a filler in an amount of 0 parts by mass or more and 30 parts by mass or less, and a component (G) that is an organic solvent in an amount of 0 parts by mass or more and 40 parts by mass or less.

[Claim 7] A one-component moisture-curable coating agent comprising the cross-linkable composition according to claim 1 or 2.

[Claim 8] A method for producing the cross-linkable composition according to claim 1 or 2, comprising: a first mixing step of blending the component (A) - (I) into a mixture of the component (A) - (II) and the component (B) ; a second mixing step of blending the component (C) into the mixture obtained in the first mixing step; and a third mixing step of blending the component (D) into the mixture obtained in the second mixing step.

[Claim 9] A method for producing a coating layer comprising: an application step of applying the cross-linkable composition according to claim 1 or 2 to a substrate; and a curing step of moisture-curing the cross-linkable composition applied in the application step.

[Claim 10] The method according to claim 9, wherein the crosslinkable composition is used in an amount of 50 g or more and 400 g or less per square meter of a substrate surface area.

[Claim 11] A method for repairing a coating layer which is a cured product of the cross-linkable composition according to claim 1 or 2, the method comprising overcoating the crosslinkable composition according to claim 1 or 2 on a surface of the coating layer.

[Claim 12] The method according to claim 9, wherein the substrate is one selected from the group consisting of a cement-based material, a gypsum board, asphalt, wood, metal, a resin, a tile, glass, a natural stone, an artificial stone, and a combination thereof.

[Claim 13] A cross-linkable composition comprising: a component (A) - (I) that is a diorganopolysiloxane having a linear or branched structure whose molecular chain terminals are blocked with a triorganosilyl group; a component (A) - (II) that is a diorganopolysiloxane having a linear or branched structure having, per molecule, at least two (R²R³NCH2) groups and at least four (OR⁴) groups

R²¹4-xSi (OR²²) _x (2)

R²²s, which may be the same as or different from each other, each represent an optionally substituted monovalent hydrocarbon group having 1 to 5 carbon atoms, with x being 2, 3, or 4 ) ; and a component (D) that is an organosilicon compound including a unit represented by the following formula (3) , in which at least one group D is present per molecule, and at least one group D has an NH2 group, DfSi (OR³²) _eR³¹dO(4-d-e-f)/2 (3)

D(s) , which may be the same as or different from each other, represents a monovalent SiC-bonded group having at least one nitrogen atom not bonded to a carbonyl group (C=0) , d is 0 or 1, e is 0, 1, 2, or 3, f is 0 or 1, and the sum of d, e, and f is 4 or less) , wherein the component (C) is blended in an amount of 10 parts by mass or more and 200 parts by mass or less relative to 100 parts by mass of a total amount of the components (A) - (I) and (A) - (II) , thereby improving repeated paintability and hardness of a cured product of the cross-linkable composition. [Claim 14] A laminate comprising: a substrate; and a coating layer obtained by curing the cross-linkable composition according to claim 1 or 2.