Title of Invention: SEALANT COMPOSITION

Technical Field

[0001] The present invention relates to a sealant composition. The sealant composition is preferably used for, for example, a building material, particularly a joint part of the building material.

Background Art

[0002] In the case that a coating material such as a paint, a putty and an adhesive is applied to a surface of a sealant, when the adhesion of the coating material to the surface is poor, there is the problem that deformation such as blistering or wrinkles of the coating material is caused.

Patent Document 1 discloses that the use of a curable composition comprising a crosslinkable silane compound having an amino group and/or a functional group which is hydrolyzed to generate an amino group, and an isocyanurate group in a molecule, and a crosslinkable silyl group-containing resin can improve the adhesion of a top coating paint, even if a matting agent is blended.

Patent Document 2 discloses that the addition of carbon black to a curable com position comprising an isocyanate group-containing urethane prepolymer and an oxygen-curable unsaturated compound can improve the adhesion of a top coating paint.

Citation List

Patent Literature

[0003] PTL 1: JP-A-2004-67782[PTL 2Patent Document 2: JP-A-2012- 193285

Summary of Invention

Technical Problem

[0004] However, when the conventional methods are used, the adhesion improvement of the coating material to the sealant is not necessarily satisfactory, and a further adhesion improvement is required. In addition, both of excellent adhesion of the coating material and excellent workability at the time of a sealing process are required.

Solution to Problem

[0005] As result of intensive studies, the present inventors discovered that the adhesion of the coating material to the sealant can be improved by combining specific particles with a polymer and a curing catalyst, and using the particles in a specific amount. Namely, the present invention provides a sealant composition comprising:

(A) a reactive polymer,

(B) particles having a particle diameter of 0.015 to 2 mm, and (C) a curing catalyst,

wherein the sealant composition comprises 0.05 to 15 % by volume, based on the sealant composition, of the particles (B).

Furthermore, the present invention provides a cured material of the sealant com position.

Advantageous Effects of Invention

[0006] The present invention can provide the sealant composition having excellent adhesion of the coating material to the surface of the sealant composition. Furthermore, according to the present invention, the sealant composition has excellent workability at the time of sealing treatment. In addition, according to the present invention, the generation of blooming at the time of adding a shine inhibitor can be prevented.

Description of Embodiments

[0007] dngredients of sealant composition>

(A) Reactive polymer

A reactive polymer comprising an arbitrary reactive group can be used as the reactive polymer. The reactive group may be at least one selected from a hydrolytic silyl group, an isocyanate group, an epoxy group, an amino group and a hydroxyl group. The reactive group is preferably a hydrolytic silyl group or an isocyanate group in view of physical properties, workability, weatherability, adhesiveness and hardenability.

[0008] Examples of the reactive polymer include a reactive group-containing polyether polymer, a reactive group-containing silicone polymer, a reactive group-containing polyurethane polymer, a reactive group-containing polysulfide polymer, a reactive group-containing acrylic polymer, a reactive group-containing polyisobutylene polymer, a reactive group-containing rubber polymer such as SBR and a butyl rubber, which may be used one alone or in combination of at least two.

[0009] Examples of the hydrolytic silyl group-containing reactive polymer include a hy drolytic silyl group-containing polyether polymer, a hydrolytic silyl group-containing silicone polymer, a hydrolytic silyl group-containing polyurethane polymer, a hy drolytic silyl group-containing polysulfide polymer, a hydrolytic silyl group-containing acrylic polymer, a hydrolytic silyl group-containing polyisobutylene polymer and hy drolytic silyl group-containing rubber polymer. Preferably, the hydrolytic silyl group- containing reactive polymer is the hydrolytic silyl group-containing polyether polymer (a modified silicone), the hydrolytic silyl group-containing acrylic polymer, and the hydrolytic silyl group-containing polyisobutylene polymer. Since physical properties can be adjusted to a low modulus and a high extension, and excellent weatherability is obtained, the alkoxysilyl group-containing polyether polymer and/or acrylic polymer are preferably used as the hydrolytic silyl group-containing reactive polymer. [0010] Examples of the isocyanate group-containing reactive polymer include an isocyanate group-containing polyether polymer, an isocyanate group-containing silicone polymer, an isocyanate group-containing polyurethane polymer, an isocyanate group-containing polysulfide polymer, an isocyanate group-containing acrylic polymer, an isocyanate group-containing polyisobutylene polymer and an isocyanate group-containing rubber polymer. Preferably, the isocyanate group-containing reactive polymer is the isocyanate group-containing polyether polymer, the isocyanate group-containing acrylic polymer and the isocyanate group-containing polyisobutylene polymer.

[0011] A weight- average molecular weight of the reactive polymer may be 1,000 to 50,000, preferably 3,000 to 40,000. Herein, the weight- average molecular weight is in terms of polystyrene. The weight- average molecular weight can be measured by gel permeation chromatography (GPC). The sealant composition may contain the reactive polymer having the above-mentioned weight-average molecular weight range in the amount of at least 5 % by weight, preferably at least 10 % by weight, based on the sealant com position.

The amount of the reactive polymer may be 5 to 60 % by weight, for example, 10 to 50 % by weight, particularly 15 to 40% by weight, based on the sealant composition.

[0012] (B) Spherical particles having particle diameter of 0.015 to 2 mm

The sealant composition contains particles including (B) spherical particles having a particle diameter of 0.015 to 2 mm. Particles contained in the sealant composition may consist of the particles (B) or may comprise other particles in addition to the particles (B). The amount of the spherical particles (B) may be 0.03 to 20 % by volume, preferably 0.05 to 15 % by volume, for example, 3 to 14 % by volume, based on the sealant composition. The spherical particles (B) may one alone or in combination of at least two. When a type of the spherical particles (B) is at least two (particularly two), the total amount of the spherical particles (B) may be at most 15 % by volume, for example, at most 12 % by volume, preferably 0.05 to 7.5 % by volume (for example, 0.1 to 3.0 % by volume), based on the sealant composition. When a type of the spherical particles (B) is one, the amount of the spherical particles (B) may be 0.05 to 5.5 % by volume, for example, 0.1 to 3.0 % by volume, based on the sealant com position. Since the sealant composition comprises the spherical particles (B), a surface area becomes large and adhesion of coating materials such as a paint applied to a sealant composition surface is improved. The tendency of the adhesiveness becomes more remarkable as the particle diameter is larger.

[0013] In the present invention, the term "spherical" means not only a shape of a true sphere, but also a shape of an ellipse and may mean a shape of an approximately sphere free from a big dimple or a keen protrusion on a particle surface. A ratio of a major axis to a minor axis of the particles (B) (major axis/minor axis) (an average of particles or each of particles) may be 1 to 3, preferably 1.01 to 2.5, particularly 1.02 to 2.

[0014] The particles (B) are solid particles at a normal temperature (20°C). A melting point of the particles (B) may be at least 50°C, preferably at least 75°C, more preferably at least l00°C, furthermore preferably at least 200°C. The particles (B) may be crystalline or glassy, for example, an inorganic glass (a silicate glass) or an organic glass.

[0015] A filler and an aggregate which are generally used can be used as the particles (B).

The particles (B) may be inorganic particles, such as a mineral, volcanic ash soil (for example, Shirasu) and ceramics; organic particles, such as a silicone resin, an epoxy resin, polystyrene, an acrylic resin and a phenol resin; and an organic-inorganic composite particle compositing an inorganic material and an organic material.

Preferably, the particles (B) are silica, alumina, silica alumina, Shirasu and glass. Particles may be treated by various surface treatment agents (for example, a silane coupling agent). The glass may be inorganic glass such as soda lime glass, borosilicate glass, silica glass, and aluminosilicate glass, or may be organic glass such as acryl or polycarbonate. The inorganic glass is preferable.

[0016] The particles (B) may have a shape of a bead or a shape of a balloon (a shape of hollow) which may have a penetration hole.

[0017] Preferably, the particles (B) are a combination of spherical particles which have different particle size distribution. Preferably, in a volume-based particle size dis tribution measurement of particles (B), a chart of a particle presence ratio obtained by plotting a particle diameter as a horizontal axis and a particle presence ratio as a vertical axis has at least two (for example, two, three and four, preferably two) local maxima in a range between 0.015 mm and 2 mm of the horizontal axis. A difference of particle diameter between one local maximum and an adjacent local maximum in the range between 0.015 mm and 2 mm of the horizontal axis may be at least 0.1 mm, for example, at least 0.2 mm, preferably at least 0.3 mm, more preferably at least 0.5 mm, particularly at least 0.7 mm.

[0018] In the present specification, mere "particle diameter" does not mean a statistical particle diameter, such as average particle diameter and a median particle diameter, but "particle diameter" means a particle diameter of each particle. In the present speci fication, "central particle diameter" means a central particle diameter (a median particle diameter) on basis of volume. The particle diameter and the central particle diameter can be measured by a well-known method, for example, according to JIS Z 8825:2013.

[0019] (Bl) First spherical particles and (B2) Second spherical particles

The particles (B) may be a combination of:

(Bl) first spherical particles having a particle diameter of 0.8 mm to 2 mm, and (B2) second spherical particles having a particle diameter of O.lmm to less than 0.8 mm.

Preferably, in a volume-based particle size distribution measurement (by a laser diffraction and scattering method using CA-950V2 manufactured by HORIBA Ltd.) of each of the first spherical particles (Bl) and the second spherical particles (B2), a chart of a particle presence ratio obtained by plotting a particle diameter as a horizontal axis and a particle presence ratio as a vertical axis has a single local maximum in the range of the above-mentioned particle diameter.

[0020] The first spherical particles (Bl) may be the same material as the second spherical particles (B2), or the first spherical particles (Bl) may be a material different from the second spherical particles (B2). For example, the first spherical particles (Bl) may be glass, and the second spherical particles (B2) may be alumina. When the first spherical particles (Bl) and the second spherical particles (B2) are used, and further when the first spherical particles (Bl) are a material different from the second spherical particles (B2), the adhesion of coating materials, such as a paint applied to the sealant com position surface is improved. In addition, a design sense peculiar to the present invention is exhibited, and a feeling (for example, sense of unity with a silica sand- containing coating material) is improved.

[0021] Preferably, the particle diameter of the first spherical particles (Bl) is 0.9 to 1.6 mm, for example, 1.0 mm to 1.4 mm. Preferably, the particle diameter of the second spherical particles (B2) is 0.15 to 0.7 mm, for example, 0.2 mm to 0.6 mm.

[0022] In the sealant composition, the amount of the first spherical particles (B 1) may be 0.05 to 15 % by volume, for example, 0.5 to 13 % by volume, more preferably 1.5 to 10 % by volume, based on the sealant composition.

[0023] In the sealant composition, the amount of the second spherical particles (B2) may be 0.05 to 15 % by volume, for example, 0.5 to 13 % by volume, preferably 1.5 to 10 % by volume, or 3 to 12 % by volume, based on the sealant composition.

[0024] A volume ratio of the first spherical particles (Bl) to the second spherical particles (B2) may be, for example, 10:90 to 90:10, preferably 20:80 to 70:30, more preferably 30:70 to 50:50, or 25:75 to 45:55.

[0025] Other particles (B')

The sealant composition may also comprise other particles (B') other than the particles (B), as other particles. The amount of the other particles (B') may be 1 to 500 parts by weight, for example, 2 to 100 parts by weight, particularly 3 to 50 parts by weight, specially 5 to 40 parts by weight, based on 100 parts by weight of the particle (B). Alternatively, the amount of the other particles (B') may be 0 to 70% by weight, for example, 0.1 to 60 % by weight, particularly 1 to 50 % by weight, based on the sealant composition.

[0026] The other particles (B') are different from particles (B). The other particles (B') may be nonspherical (for example, fibrous or needle-like). A particle diameter of other particles (B') may be at most 90 micrometers, for example, 1 nm to 85 micrometers, particularly 5 nm to 80 micrometers. Examples of the other particles (B') include calcium carbonate, fatty acid-treated calcium carbonate, fumed silica, sedimentary silica, carbon black, talc, mica, clay, glass beads; balloons such as a Shirasu balloon, a glass balloon, a silica balloon and a plastic balloon; inorganic fibers such as a glass fiber and a metal fiber; organic fibers, such as a polyethylene fiber and a

polypropylene fiber; a needle crystal fillers such as aluminum borate, silicon carbide, silicon nitride, potassium titanate, graphite, needle crystal calcium carbonate, magnesium borate, titanium diboride, chrysotile and wollastonite.

[0027] The sealant composition may also comprise scale particles as the other particles (B').

The scale particles may have a particle diameter (or central particle diameter) of at most 2 mm, for example, 1 micrometer to 1.5 mm, particularly 5 micrometers (0.005 mm) to 1.0 mm. In the scale particles, an aspect ratio of an average particle diameter to an average thickness (average particle diameter/average thickness) may be 5 to 200, for example, 10 to 100, preferably 20 to 60. Herein, the particle diameter of scale particles means a major axis (a maximum diameter) of the scale particles. Examples of the scale particles include scale mica (for example, scale black mica) and scale silica. The amount of the scale particles may be 1 to 300 parts by volume, for example, 2 to 100 parts by volume, particularly 3 to 50 parts by volume, based on 100 parts by volume of the particle (B).

The particles contained in the sealant composition may consist of the particles (B) or may consist of the particles (B) and the other particles (B').

[0028] (C) Curing catalyst

The sealant composition comprises a curing catalyst (C). The curing catalyst (C) may be a tin compound and is preferably a compound of tetravalent tin.

[0029] In the sealant composition, the amount of the curing catalyst (C) may be 0.01 to 5 % by weight, preferably 0.1 to 2.5 % by weight, based on the sealant composition.

[0030] The curing catalyst (C) may comprises a combination of

(Cl) a silyl group-containing curing catalyst, and

(C2) a silyl group-free curing catalyst.

Any of the curing catalyst can be used. When the catalyst (C2) is used as the curing catalyst, the adhesiveness can be improved, but when used together with amine, a problem of blooming might be caused. When the amine is used together with a com bination of the catalyst (Cl) and the catalyst (C2), the adhesiveness is improved without the problem of blooming. A weight ratio of the curing catalyst (Cl) to the curing catalyst (C2) [catalyst (Cl)/catalyst (C2)] is preferably 1/10 to 10/1, more preferably 3/10 to 10/3, still more preferably 7/10 to 10/7. [0031] (Cl) Silyl group-containing curing catalyst

Examples of the silyl group-containing curing catalyst (Cl) include alkyl tin alkoxy silicate such as dibutyl tin alkoxy silicate and dioctyl tin alkoxy silicate, for example, dibutyl tin bis trialkoxy silicate, dibutyl tin bis dialkoxy silicate, dibutyl tin trialkoxy silicate and dibutyl tin dialkoxy silicate, preferably dibutyl tin bis trialkoxy silicate, more preferably dibutyl tin bis triethoxy silicate. The carbon number of the alkoxy group or the alkyl group in alkyl tin alkoxy silicate may be 1 to 8, preferably 1 to 4, more preferably 1 to 2.

[0032] (C2) Silyl group-free curing catalyst

Examples of the silyl group-free curing catalyst (C2) include tin curing catalysts such as a tin dioctoate, dibutyltin dilaurate, dibutyl tin bis acetylacetonate, dibutyltin diacetate, dibutyl tin diethyl hexanoate, dibutyl tin dioctoate, dibutyl tin oxide, and dioctyl tin oxide; and titanium curing catalysts such as tetraisopropyl titanate, tetra n- butyl titanate, partial hydrolysis condensate thereof, titanium diisopropyl bisacety- lacetate and titanium diisopropyl bisethylacetoacetate.

[0033] (D) Secondary or primary amine having melting point of -30 to l20°C

Preferably, the sealant composition comprises (D) a secondary or primary amine having a melting point of -30°C to l20°C. The amine (E) can decrease a shine on a surface of a cured material of the sealant composition. Examples of the amine (D) include lauryl amine, stearyl amine, phenyl amine, benzyl amine, decane diamine and dodecane diamine.

The amount of the amine (D) may be 0.01 to 10 % by weight, for example, 0.1 to 5 % by weight, particularly 0.2 to 3% by weight, based on the sealant composition.

[0034] (E) Plasticizer

The sealant composition may contain (E) a plasticizer. The plasticizer (E) may be a reactive plasticizer or a non-reactive plasticizer.

[0035] The reactive plasticizer may be a polyalkylene ether polymer having an average number of a hydrolytic silyl group of 0.5 to 1.2 in a molecule. A weight- average molecular weight of the polyalkylene ether polymer may be 300 to 8,000. Specific examples thereof include S-1000N manufactured by Asahi Glass Urethane Co., Ltd. The reactive plasticizer may be an acrylic polymer having a (meth) acrylate ester unit and having an average number of a hydrolytic silyl group of 0.1 to 1.2 in a molecule. The acrylic polymer may comprise, in addition to the (meth) acrylate ester unit, a unit formed from a monomer (such as an olefin having 4-12 carbon atoms, a vinyl ether, an aromatic vinyl compound, a vinyl silane and an allyl silane) which can be

copolymerized with the (meth)acrylate ester. The weight- average molecular weight of the acrylic polymer may be 300 to 8,000. Specific examples thereof include US-6170 manufactured by Toagosei Co., Ltd. The reactive plasticizers may be one alone or in combination of at least two.

[0036] Examples of the non-reactive plasticizer include polyalkylene ethers, phthalate

diesters, epoxidized hexahydrophthalate diesters, alkylene dicarboxylate diesters, alkyl benzenes, castor oils, phosphate esters, epoxidized soybean oils and epoxidized olefin plasticizers. The non-reactive plasticizer may be one alone or in combination of at least two. Preferably, the alkyl benzenes and/or the epoxidized plasticizer are used as the plasticizer, or as a part of the plasticizer. The epoxidized plasticizer has a function of catching, for example, a floating amine to have an effect of improving durability. The use of the epoxidized olefin plasticizer can give a low viscosity.

[0037] The amount of the plasticizer may be 1 to 40% by weight, preferably 5 to 15% by weight, based on the sealant composition. The amount of the reactive plasticizer and/or non-reactive plasticizer may be 1 to 40% by weight, preferably 5 to 30% by weight, particularly 10 to 20% by weight, based on the sealant composition.

[0038] (F) Other additive agent

The sealant composition may comprise another additive agent (F) in addition to the above-mentioned ingredients. Examples of the other additive agent (F) include a colorant, an organic solvent (for example, methanol, ethanol, isopropyl alcohol, butanol, acetone, methyl ethyl ketone, ligroin, ethyl acetate, tetrahydrofuran, n-hexane, heptane and an isoparaffin high-boiling point solvent), an adhesion agent (for example, silane coupling agents such as vinyl trimethoxy silane, vinyl triethoxy silane, amino silane, mercapto silane and epoxy silane and epoxy compounds such as glycidyl ether having a polyoxy alkylene skeleton), antiaging agents (for example, hindered phenols, mercaptans, sulfides, dithiocarboxylate salts, thioureas, thiophosphates and

thioaldehydes), hydration agents (such as water and a hydrate of inorganic salt), ul traviolet absorbers and light stabilizers (such as benzotriazoles and hindered amines), antioxidants (for example, hindered phenols), and thixotropic agents (for example, colloidal silica, organic bentonite, fatty acid amide and hydrogenated castor oil).

[0039] The amount of other additive agents (F) may be 0 to 80 % by weight, preferably 1 to 60 % by weight, more preferably 2 to 50 % by weight, for example, 3 to 40 % by weight, based on the sealant composition.

[0040] Coated surface>

A coated surface of the sealant composition exhibits an excellent designability, since the coated surface exhibits feeling which has characteristic protrusions.

The coated surface may have protrusions on the surface. Preferably, the coated surface may have protrusions having a height of 10 to 300 micrometers and/or at least 500 micrometers.

[0041] The height of each protrusion can be measured as a length up to a maximum top on basis of a maximum bottom by using a picture of a microscope. [0042] The coated surface may have at least 5 protrusions per 1 cm ² surface wherein the pro trusions have a height of at least 10 micrometers. Preferably, the coated surface has protrusions having a height of at least 500 micrometers (for example, 600 to 2,000 mi crometers, particularly 800 to 1,600 micrometers), in addition to protrusions having a height of 10 micrometers to less than 500 micrometers (for example, 100 micrometers to less than 500 micrometers). Preferably, the coated surface has at least 10 protrusions per 1 cm ² surface wherein the protrusions have a height of 10 to 300 micrometers (for example, 100 to 300 micrometers), and at least 5 protrusions per 1 cm ² surface wherein the protrusions have a height of at least 500 micrometers. Preferably, the coated surface has at least 10 protrusions per 1 cm ² surface wherein the protrusions have a height of at least 500 micrometers.

[0043] The protrusion may be a roundish protrusion. The "roundish" protrusion means that the protrusion does not substantially have a sharp portion, and consists of a gentle rise and fall.

[0044] A maximum of the height of the protrusion on the coated surface may be 10 to 1,600 micrometers, for example, 30 to 1,400 micrometers, preferably 100 to 1,200 mi crometers, more preferably 500 to 1,000 micrometers. When the maximum of the height of the protrusion is in such a range, a feeling peculiar to the present invention is easily exhibited. The feeling peculiar to the present invention becomes remarkable, when the coated surface has both of the protrusions having the maximum height of 100 to less than 500 micrometers, and the protrusions having the maximum height of at least 500 micrometers (preferably 500 to 1,000 micrometers).

[0045] <Curing>

The sealant composition is cured by a well-known method. For example, the curing begins with moisture in the air. The cured surface has the above-mentioned pro trusions.

[0046] The sealant composition may be:

a one-liquid type wherein the above-mentioned ingredients are mixed together; a two-liquid type having a base material comprising the above-mentioned reactive polymer, and a curing agent comprising the curing catalyst; or

a three-liquid type additionally comprising a further component of a toner comprising the colorant and the plasticizer.

[0047] The sealant composition of the present invention can be suitably used for, e.g.,

building materials, particularly a joint part in building materials such as an outer wall, an exterior and an interior.

Examples

[0048] Examples and Comparative Examples are illustrated below to more concretely explain the present invention. Units shown are based on weight, unless indicated otherwise. Procedures of tests are as follows.

[0049] Adhesion to coating material

Adhesion to a coating material was determined on the following test methods and criteria.

A coating material was applied to a cured material surface of a sealant composition, and cured at 23°C and 50%RH for 14 days. According to "5-6. Adhesion test

(Cross-cut test)" of testing methods for paints of JIS K 5600 1999, after putting a cutter onto the coating material surface (25 squares, an cut line interval of 4 mm), a gum tape was stuck on the surface and pulled off upward once, and the number of the squares which separated from the surface was recorded.

Very good: Peeling of at most 2 squares: Very good adhesion

Good: Peeling of at most 9 squares: Good adhesion

Bad: Peeling of at least 10 squares: Bad adhesion

[0050] Shine property

A Shine property was determined on the following test method and criteria. A degree of brilliancy at an incident angle of 60 degrees was recorded by a gloss meter (GM268 manufactured by Konica Minolta Inc.) for a cured material surface after a sealant was cured at 23°C and 50%RH for 14 days.

Good: Without shine: Gloss degree of 0 to 10

Bad: With shine: Gloss degree of at least 11

[0051 ] Blooming property

A blooming property was determined on the following test method and criteria. The existence of whether white crystals (white powder having less than 10 micrometers) have uniformly adhered to a cured material surface of a sealant was visually monitored after the sealant was cured at 23°C and 50%RH for 14 days.

Good: Adhesion of crystals

Bad: No adhesion of crystals

[0052] Workability

Workability was determined on the following two test methods and criteria. A sealant was tested according to "5.1 Slump tests" of "Test methods of sealants for building" in JIS A 1439 2016. A test temperature was 50°C. On the other hand, the sealant was tested according to "5.18 Application life tests" of test methods of sealants in JIS A 1439 2016. The test was conducted at a temperature of 23°C and RH 50%.

Good: Slump of not larger than 1 mm, and Application life of not larger than 4 hour: Good workability

Bad: Slump of larger than 1 mm, and Application life of larger than 4 hours: Poor workability [0053] Maximum value of protrusion height

A height (length from a maximum bottom to a maximum top) of protrusions on a cured material surface of a sealant was measured by using a microscope (VHX-1000 manufactured by KEYENCE Corporation) to determine a maximum of the height.

[0054] Feeling

Feeling of a cured material surface of a sealant was determined on the following criteria as a sense of unity over a silica sand-containing coating material having a particle diameter of 0.3 to 0.8 mm. The silica sand-containing coating material has an appearance which can be called as a shape of a sand wall, a shape of skin of a citrona small citrus fruit, or a shape of stucco shown in "4. Types and names" of JIS A 6909 2014, and particularly has an appearance which can be called as a shape of exterior thick coating stucco.

(1) Number of protrusions having a height of at least 500 micrometers

(Basically, particles having a large particle diameter are measured)

(2) Number of protrusions having a height of 10 to less than 500 micrometers

The evaluation criteria of the feeling are as follows:

Bad: Number (1) is less than 5 protrusions/cm ² and Number (2) is less than 10 pro trusions/cm ²

Fair-Good: Number (1) is at least 5 protrusions/cm ² and Number (2) is less than 10 protrusions/cm ²

Fair-Good: Number (1) is less than 5 protrusions/cm ² and Number (2) is at least 10 protrusions/cm ²

Good: Number (1) is at least 5 protrusions/cm ² and Number (2) is at least 10 pro trusions/cm ²

Very Good: Number (1) is at least 10 protrusions/cm ² and Number (2) is at least 10 protrusions/cm ²

Bad: Existence of irregularity or line on surface

[0055] Example 1

After ingredients having the number of parts by weight shown in Example 1 of the following Table 1 excluding a curing catalyst and an adhesion agent were mixed in a planetary mixer for 60 minutes, and mixed at 80°C under vacuum for 2 hours. Next, the ingredients were cooled to 30°C, and the adhesion agent and the curing catalyst were mixed with the ingredients and stirred at most 30°C under vacuum for 15 minutes, to obtain a sealant composition. A specific gravity of the obtained sealant composition was about 1.4. The above-mentioned tests were performed on the obtained sealant composition. The results are shown in Table 1.

[0056] Examples 2 to 8 and Comparative Examples 1 to 3

A sealant composition was obtained as in Example 1 except using ingredients shown in Tables 1 and 2. The above-mentioned test was performed on the obtained sealant composition. The specific gravity of the obtained sealant composition was about 1.4. The results is shown in Tables 1 and 2.

[0057]

Table 2

[0059] The ingredients shown in Tables 1 and 2 are specifically as follows:

Polymer: "S810" (modified silicone polymer) manufactured by KANEKA

Plasticizer: "DINP" (diisononyl phthalate) manufactured by New Japan Chemical Co., Ltd.

Filler: "CCR-B" (Nonspherical calcium carbonate surface-treated with a fatty acid) (Primary particle diameter of 0.08 micrometer) manufactured by Shiraishi Calcium Kaisha, Ltd.

Adhesion agent: "Sila-Ace (registered trademark) S-220" and "Sila-Ace (registered trademark) S-210" manufactured by Chisso Corp.

Additive agent:”ADK STAB (registered trademark) AO-60” and”ADK STAB (registered trademark) LA-32" manufactured by ADEKA

Primary amine compound: "FARMIN 20D" (primary fat amine) manufactured by Kao Corp. Curing catalyst x: "NEOSTANN (registered trademark) U-303" (dibutyl tin bis triethoxy silicate) manufactured by Nitto Kasei Co. Ltd.

Curing catalyst y: "NEOSTANN (registered trademark) U-220" (dibutyl tin acety- lacetonate) manufactured by Nitto Kasei Co. Ltd.

Spherical particles a: "GB30ls" (glass beads) (Particle diameter of 35-45 micrometers, True specific gravity of 2.5) manufactured by 3M Japan Limited

Spherical particles b: "GB503M" (glass beads) (Particle diameter of 1,400-2,000 mi crometers, True specific gravity of 2.5) manufactured by Potters-Ballotini Co., Ltd. Spherical particles c: "GB603M" (glass beads) (Particle diameter of 2,000-3,350 mi crometers, True specific gravity of 2.5) manufactured by Potters-Ballotini Co., Ltd. Spherical particles d: "Y-1014" (glass beads) (particle diameter of 1,000-1,400 mi crometers, True specific gravity of 2.5) manufactured by Bright Hyoshiki Reflective Indicator Co., Ltd.

Spherical particles e: "REXX 500" (alumina) (Particle diameter of 300-700 mi crometers, True specific gravity 1.06) manufactured by Mizuno Clay Co. Ltd.

Spherical particles f: "GB103T" (glass beads) (Particle diameter of 300-700 mi crometers, True specific gravity of 2.5) manufactured by Potters-Ballotini Co., Ltd. Spherical particles g: "Y-0812" (glass beads) (Particle diameter of 850-1180 mi crometers, True specific gravity of 2.5) manufactured by Bright Hyoshiki Reflective Indicator Co., Ltd.

Scale particles: "GB-AKH50" (mica) (Central particle diameter of 50 micrometers, True specific gravity of 2.9) manufactured by HOKUTO SANGYO Ltd.