Curable polyorganosiloxane composition and use thereof, and hydrolyzable silane compound containing benzimidazolidinone moiety

Abstract

The present invention provides: a curable silicone composition which has excellent corrosion resistance and excellent uniformity; and a compound which can impart excellent corrosion resistance and excellent uniformity to a curable silicone composition. The present invention relates to: a curable polyorganosiloxane composition which comprises (A) a polyorganosiloxane having, per molecule, two or more hydrolyzable groups bonded to a silicon atom, (B) a curing catalyst, and (C) a compound containing, per molecule, a benzimidazolidinone moiety and a hydrolyzable group bonded to a silicon atom; and the component (C).

Description

Curable polyorganosiloxane composition, its uses, and hydrolyzable silane compound containing a benzimidazolidinone moiety

[0001] The present invention relates to a curable polyorganosiloxane composition, its uses, and a hydrolyzable silane compound containing a benzimidazolidinone moiety.

[0002] Among polyorganosiloxane compositions that harden at room temperature to form a rubber-like elastomer, those that undergo a hardening reaction upon contact with moisture in the air eliminate the need to weigh and mix the main body (base polymer), crosslinking agent, catalyst, etc. immediately before use, and are free of the risk of compounding errors. In addition, they have excellent adhesive properties, and are therefore widely used as coating materials for the electrical and electronic industries, as well as sealing materials for construction, etc.

[0003] As such coating materials, Patent Documents 1 and 2 describe room-temperature curable polyorganosiloxane compositions containing a polyorganosiloxane having alkoxy groups bonded to the terminal silicon atoms, an alkoxysilane, and a curing catalyst.

[0004] JP-A No. 62-252456 JP-A No. 4-293962

[0005] As electrodes and wiring in LCDs (Liquid Display Panels) and PDPs (Plasma Display Panels) become increasingly miniaturized, corrosion and migration of the electrodes and wiring are becoming more common. Corrosion of electrodes and wiring is thought to be caused by trace amounts of corrosive gases, such as hydrogen sulfide and sulfuric acid gas, present in the atmosphere, or by salt water. Therefore, there is a demand for coating materials that are highly effective in preventing corrosion of electrodes and wiring.

[0006] Room-temperature-curable polyorganosiloxane compositions containing a polyorganosiloxane having alkoxy groups bonded to terminal silicon atoms, an alkoxysilane, and a curing catalyst, as described in Patent Documents 1 and 2, have had the problem that the resulting coatings may have poor corrosion prevention (corrosion resistance). Furthermore, room-temperature-curable polyorganosiloxane compositions containing 1,2,3-benzotriazole, which is used as a rust inhibitor, have had the problem of poor composition uniformity.

[0007] An object of the present invention is to provide a curable silicone composition that has excellent corrosion resistance and uniformity. Another object of the present invention is to provide a compound that can impart excellent corrosion resistance and uniformity to the curable silicone composition.

[0008] That is, the present invention relates to the following [1] to [9]. [1] A curable polyorganosiloxane composition comprising: (A) a polyorganosiloxane having two or more silicon-bonded hydrolyzable groups per molecule and no benzimidazolidinone moieties; (B) a curing catalyst; and (C) a compound containing a benzimidazolidinone moiety and a silicon-bonded hydrolyzable group per molecule. [2] The curable polyorganosiloxane composition according to [1], wherein component (C) is a compound containing one or two benzimidazolidinone moieties, a siloxane chain, and a silicon-bonded hydrolyzable group per molecule. [3] The curable polyorganosiloxane composition according to [1], wherein component (C) is a compound represented by the following general formula (1), (2), or (3): [In the formula, A １ is expressed by formula (4) or (5): (In formula (4), R ２１ is a hydrogen atom or a hydrocarbon group) (In formula (5), R ２２ and R ２３ are each independently a hydrogen atom or a hydrocarbon group, １ is an alkylene group which may be interrupted by —S—, an alkylene group which may be interrupted by —NH—, or an alkylene group which may be interrupted by a linear or cyclic siloxane chain, and R １are each independently a hydrolyzable group or a hydrocarbon group, provided that at least one R １ is a hydrolyzable group. [In the formula, A ２ and A ３ are each independently a group represented by formula (4) or (5), ２ and X ３ are each independently an alkylene group which may be interrupted by —S—, an alkylene group which may be interrupted by —NH—, or an alkylene group which may be interrupted by a linear or cyclic siloxane chain; R ２ are each independently a hydrolyzable group or a hydrocarbon group, provided that at least one R ２ is a hydrolyzable group, R ３ are each independently a hydrocarbon group; １ is 0 or a number from 1 to 1,000. [In the formula, A ４ is a group represented by formula (4) or (5), ４ and X ５ are each independently an alkylene group which may be interrupted by —S—, an alkylene group which may be interrupted by —NH—, or an alkylene group which may be interrupted by a linear siloxane chain; R ４ are each independently a hydrocarbon group, R ５ are each independently a hydrolyzable group or a hydrocarbon group, provided that at least one R ５ is a hydrolyzable group, a is an integer of 1 or more, and when a is an integer of 2 or more, each A ４ , X ４ and R ４ are the same or different, b is 0 or an integer of 1 or more, and when b is an integer of 2 or more, each X ５ , R ４ and R ５ are the same or different, c is 0 or an integer of 1 or more, and when c is an integer of 2 or more, each R ４are the same or different, and a + b + c is an integer of 3 or greater. [4] The curable polyorganosiloxane composition according to any one of [1] to [3], further comprising one or more selected from the group consisting of (D) a crosslinking agent, (E) an adhesion promoter, and (F) a polyorganosiloxane having no silicon-bonded hydrolyzable groups. [5] A coating agent for electronic components using the curable polyorganosiloxane composition according to any one of [1] to [4]. [6] A metal surface treatment agent using the curable polyorganosiloxane composition according to any one of [1] to [4]. [7] A cured product obtained by curing the curable polyorganosiloxane composition according to any one of [1] to [4]. [8] An electronic component comprising the curable polyorganosiloxane composition according to any one of [1] to [4]. [9] (C) A compound containing a benzimidazolidinone moiety and a hydrolyzable group bonded to a silicon atom in one molecule.

[0009] The present invention provides a curable silicone composition that exhibits excellent corrosion resistance and uniformity. Another object of the present invention is to provide a compound that can impart excellent corrosion resistance and uniformity to a curable silicone composition.

[0010] [Definition of Terms] The structural units of siloxane compounds may be expressed by the following abbreviations (hereinafter, these structural units are referred to as "M unit" and "D unit", respectively). Ｈ (It is sometimes called "unit" etc.) M 　 :(CH ３ ) ３ SiO １／２ M Ｈ :(CH ３ ) ２ HSiO １／２ M Ｖ :(CH ３ ) ２ (CH ２ =CH)SiO １／２ D 　 :(CH ３ ) ２ SiO ２／２ D Ｈ :(CH３ ) HSiO ２／２ D Ｖ :(CH ３ ) (CH ２ =CH)SiO ２／２ T 　 :CH ３ SiO ３／２ Q 　 : SiO ４／２ (Tetrafunctionality)

[0011] In this specification, the use of "to" to indicate a range of values ​​means that the values ​​before and after it are included as the lower and upper limits.

[0012] In this specification, the viscosity is a value measured at 23° C. Specifically, it is a value measured under the conditions described in the examples.

[0013] In this specification, "(A) a polyorganosiloxane having two or more silicon-bonded hydrolyzable groups per molecule and no benzimidazolidinone moiety" is also referred to as "component (A)." The same applies to "(B) a curing catalyst," etc.

[0014] As used herein, the term "hydrocarbon group" refers to a group obtained by removing at least one hydrogen atom from a hydrocarbon molecule containing carbon atoms and hydrogen atoms, depending on the valence of the hydrocarbon group. The hydrocarbon group may be substituted with one or more substituents. Examples of the substituents include a halogen atom and a cyano group.

[0015] Examples of the monovalent hydrocarbon group include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, and an alkenyl group. Examples of the monovalent hydrocarbon group having no aliphatic unsaturated bond include the above-mentioned monovalent hydrocarbon groups other than an alkenyl group.

[0016] The alkyl group is a linear or branched group having 1 to 18 carbon atoms, and examples thereof include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, hexadecyl, and octadecyl. The cycloalkyl group is a monocyclic or polycyclic group having 3 to 20 carbon atoms, and examples thereof include cyclopentyl, cyclohexyl, and cycloheptyl. The aryl group is an aromatic group containing a monocyclic or polycyclic group having 6 to 20 carbon atoms, and examples thereof include phenyl, tolyl, xylyl, and naphthyl. The aralkyl group is an alkyl group substituted with an aryl group, and examples thereof include benzyl, 2-phenylethyl, and 2-phenylpropyl. The alkenyl group is a straight-chain or branched group having 2 to 6 carbon atoms, and examples thereof include a vinyl group, an allyl group, a propenyl group, a 3-butenyl group, and a 5-hexenyl group.

[0017] The monovalent hydrocarbon group may be unsubstituted or substituted with a halogen or a cyano group. Examples of alkyl groups substituted with a halogen include a chloromethyl group, a bromoethyl group, a chloropropyl group, a 3,3,3-trifluoropropyl group, and a 3,3,4,4,5,5,6,6,6-nonafluorohexyl group. Examples of aryl groups substituted with a halogen include a chlorophenyl group. Examples of alkyl groups substituted with a cyano group include a 2-cyanoethyl group.

[0018] A divalent hydrocarbon group is a group obtained by removing one hydrogen atom from the above-mentioned monovalent hydrocarbon group. The divalent hydrocarbon group is preferably an alkylene group. The alkylene group is a linear or branched group having 1 to 18 carbon atoms, and examples thereof include a methylene group, an ethylene group, a trimethylene group, a 2-methylethylene group, and a tetramethylene group. The divalent hydrocarbon group may be unsubstituted or substituted with a halogen or a cyano group.

[0019] [Curable Polyorganosiloxane Composition] The curable polyorganosiloxane composition (hereinafter also simply referred to as "composition") contains (A) a polyorganosiloxane having two or more hydrolyzable groups bonded to silicon atoms in one molecule and no benzimidazolidinone moiety, (B) a curing catalyst, and (C) a compound containing, in one molecule, a benzimidazolidinone moiety and one or more selected from the group consisting of a hydrolyzable group bonded to a silicon atom and a siloxane chain.

[0020] The composition has excellent corrosion resistance and uniformity, as well as excellent heat resistance, reliability (heat cycle resistance), etc. The corrosion resistance is preferably resistance to corrosive gases such as hydrogen sulfide gas and sulfuric acid gas, or salt water, and is particularly preferably resistance to sulfur or salt water.

[0021] [(A) Polyorganosiloxane Having Two or More Silicon-Bonded Hydrolyzable Groups Per Molecule and No Benzimidazolidinone Moiety] Component (A) is a polyorganosiloxane having two or more silicon-bonded hydrolyzable groups per molecule. Component (A) is a component that serves as the base polymer in the composition.

[0022] In this specification, "polyorganosiloxane" refers to a component having a siloxane bond (-Si-O-Si) and at least two silicon atoms per molecule. Component (A) has at least two silicon atoms per molecule, preferably at least three silicon atoms per molecule, and particularly preferably 10 or more silicon atoms per molecule.

[0023] Component (A) does not have a benzimidazolidinone moiety. Specifically, component (A) does not have a benzimidazolidinone moiety, which will be described later. Therefore, component (A) does not fall under the category of component (C), which will be described later.

[0024] <Hydrolyzable Group> Examples of the hydrolyzable group include -OR', -OCOR', and -O-N=CR'. ２ , -NR' ２ , —NHR′, a halogen atom, etc. In these formulas, R′ is an alkyl group.

[0025] The hydrolyzable group is preferably —OR′ (i.e., an alkoxy group). R′ is preferably a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, more preferably an unsubstituted alkyl group having 1 to 4 carbon atoms, and particularly preferably a methyl group or an ethyl group. Therefore, the hydrolyzable group is particularly preferably a methoxy group or an ethoxy group.

[0026] <Structure of Component (A)> The structure of component (A) is not particularly limited as long as it has an average of two or more hydrolyzable groups bonded to silicon atoms per molecule. Component (A) is typically represented by the general formula (5): (R ａ ) ｓ (R ６ ) ｔ SiO （４－ｓ－ｔ）／２ (5) (wherein, R ａ is a hydrolyzable group; R ６ is a monovalent hydrocarbon group having no aliphatic unsaturated bonds; s is an integer of 1 to 3; and t is an integer of 0 to 2, with the proviso that s+t is 1 to 3) in the molecule.

[0027] Component (A) is a compound represented by the following general formula (6): (R ａ ) ３－ｐ R ６ ｐ Si-O-(Si(R ６ ) ｒ (R ａ ) ２－ｒ O) ｎ -SiR ６ ｑ (R ａ ) ３－ｑ ...(6) (in the formula, R ａ are each independently a hydrolyzable group, and R ６are each independently a monovalent hydrocarbon group having no aliphatic unsaturated bonds, p and q are each independently 0, 1, or 2, r is each independently 0, 1, or 2, and n is a number that gives a viscosity at 23°C of 100 mPa·s to 500,000 mPa·s.

[0028] R ６ is preferably an alkyl group or an aryl group.

[0029] From the viewpoint of controlling physical properties such as refractive index, R ６ At least a part of R may be an aryl group such as a phenyl group. ６ In view of ease of availability, polyorganosiloxanes in which all r are methyl are preferred. It is also preferred that r is 2. That is, component (A) is preferably a linear polyorganosiloxane in which at least one hydrolyzable group is present only at each end of the molecule.

[0030] Therefore, component (A) has R at both ends. ａ ３－ｍ R ６ ｍ SiO １／２ It is blocked by units, and the intermediate unit is R ６ ２ SiO ２／２ The linear polyorganosiloxane unit (wherein R ａ is a hydrolyzable group, and R ６ is a monovalent hydrocarbon group having no aliphatic unsaturated bonds, and m is 0, 1 or 2).

[0031] It is particularly preferred that component (A) be one in which p and q in formula (6) are 0 or 1, that is, one having two or more hydrolyzable groups at each of the molecular terminals.

[0032] The viscosity of component (A) is preferably 10 mPa·s to 500,000 mPa·s, and particularly preferably 150 mPa·s to 100,000 mPa·s, at 23° C. When the viscosity of component (A) is within this range, saltwater resistance and uniformity tend to be better.

[0033] Component (A) can be a commercially available product, or a polyorganosiloxane into which a hydrolyzable group has been introduced by a known reaction.

[0034] Component (A) may be a single component or a combination of two or more components.

[0035] [(B) Curing Catalyst] Component (B) is a curing catalyst. Component (B) is a component that promotes hydrolysis and condensation of component (A), component (C) containing a silicon-bonded hydrolyzable group, and optionally present crosslinking agent (D). Examples of component (B) include metal catalysts, organic acid catalysts, inorganic acid catalysts, and base catalysts. Note that the organic acid catalysts, inorganic acid catalysts, and base catalysts do not contain metal atoms.

[0036] Examples of the metal catalyst include metal carboxylates and organometallic compounds. Examples of metals contained in the metal catalyst include titanium, zirconium, tin, aluminum, iron, manganese, and zinc.

[0037] The metal carboxylate is not particularly limited as long as it is a carboxylic acid compound containing the above metal, and preferred examples of the metal carboxylate include iron octoate, manganese octoate, zinc octoate, tin naphthate, tin caprylate, and tin oleate.

[0038] The organometallic compound is not particularly limited as long as it is an organic compound containing the above-mentioned metal, and the organometallic compound is preferably an organotitanium compound, an organozirconium compound, an organotin compound, an organoaluminum compound, or the like.

[0039] Examples of the organic titanium compound include tetraethoxytitanium, tetrapropoxytitanium, tetraisopropoxytitanium, tetra-n-butoxytitanium, tetraisobutoxytitanium, diisopropoxytitanium bis(ethylacetoacetate), 1,3-propanedioxytitanium bis(ethylacetoacetate), and the like.

[0040] Examples of the organic zirconium compound include zirconium tetraacetylacetonate, tetraisopropoxyzirconium, tetrapropoxyzirconium, tetra-n-butoxyzirconium, tetraisobutoxyzirconium, tributoxyzirconium acetylacetonate, and tributoxyzirconium stearate.

[0041] Examples of organotin compounds include dibutyltin diacetate, dibutyltin dioctoate, dibutyltin dilaurate, dibutyltin diolate, diphenyltin diacetate, dibutyltin oxide, dibutyltin dimethoxide, dibutylbis(triethoxysiloxy)tin, dioctyltin dilaurate, and dimethyltin dineodecanoate.

[0042] Examples of the organoaluminum compound include aluminum trisacetylacetonate, aluminum trisethylacetoacetate, diisopropoxyaluminum ethylacetoacetate, and triethoxyaluminum.

[0043] Examples of the organic acid catalyst include compounds having a carboxylic acid group, a sulfonic acid group, and a phosphoric acid group. Preferred examples of the organic acid catalyst include acetic acid, trifluoroacetic acid, methanesulfonic acid, toluenesulfonic acid, and alkylphosphoric acid.

[0044] Examples of inorganic acid catalysts include hydrochloric acid and sulfuric acid.

[0045] Examples of basic catalysts include amine compounds such as ammonia, triethylamine, and diethylamine; dialkylhydroxylamines such as dimethylhydroxyamine and diethylhydroxylamine; and guanidyl compounds such as tetramethylguanidine, guanidyl group-containing silanes, and guanidyl group-containing siloxanes.

[0046] Component (B) is preferably a metal catalyst. Metal catalysts are easily dissolved or dispersed in the composition, which can contribute to promoting a uniform reaction. Metal catalysts contain less foreign matter, which can contribute to the formation of a transparent cured product of the composition. Component (B) is particularly preferably an organotitanium compound.

[0047] Component (B) may be a single component or a combination of two or more components.

[0048] [(C) Compound Containing a Benzimidazolidinone Moiety and a Hydrolyzable Group Bonded to a Silicon Atom in One Molecule] Component (C) is a compound containing a benzimidazolidinone moiety and a hydrolyzable group bonded to a silicon atom in one molecule. Component (C) is a hydrolyzable silane compound containing a benzimidazolidinone moiety.

[0049] When component (C) contains a silicon-bonded hydrolyzable group, the crosslinking reaction with other components proceeds, thereby enabling the effects of the present invention to be efficiently achieved.

[0050] <Benzimidazolidinone Moiety> The benzimidazolidinone moiety is a group in which one or more hydrogen atoms have been removed from benzimidazolidinone (also called 2(1H)-benzimidazolone, 2-hydroxybenzimidazole, or 1,3-dihydro-2H-benzimidazol-2-one) represented by the following structural formula.

[0051]

[0052] The benzimidazolidinone moiety is a monovalent group formed by removing a hydrogen atom from the secondary amino group (NH group) of unsubstituted or substituted benzimidazolidinone, or a primary amino group (NH ２ The benzimidazolidinone moiety is preferably a monovalent group obtained by removing a hydrogen atom from the benzimidazolidinone moiety (a group). Specifically, the benzimidazolidinone moiety is preferably a group represented by the following formula (4) or (5). In addition, the group R ２１ As shown in the formula (5), one secondary amino group of the benzimidazolidinone may be unsubstituted or substituted. ２２ and R ２３ As shown in the formula (I), one or two secondary amino groups of the 5-amino-2-benzimidazolidinone may be unsubstituted or substituted.

[0053] (In formula (4), R ２１is a hydrogen atom or a hydrocarbon group)

[0054] (In formula (5), R ２２ and R ２３ are each independently a hydrogen atom or a hydrocarbon group.

[0055] <Silicon Atom-Bonded Hydrolyzable Group> The silicon atom-bonded hydrolyzable group is as described above for component (A).

[0056] <Other Groups> Component (C) can contain other groups. Examples of such groups include alkylene groups which may be interrupted by -S-, alkylene groups which may be interrupted by -NH-, alkylene groups which may be interrupted by linear or cyclic siloxane chains, and siloxane chains. When component (C) contains a siloxane chain, the compatibility of component (C) with other components in the composition can be improved. This allows the effects of the present invention to be more efficiently achieved. Here, an "alkylene group which may be interrupted by -S-" means that the C-C bond in the alkylene group is interrupted by one -S- or is uninterrupted. The same applies to an "alkylene group which may be interrupted by -NH-" and an "alkylene group which may be interrupted by linear or cyclic siloxane chains."

[0057] <Siloxane Chain> The siloxane chain can be a linear, branched, cyclic, or combination thereof. ７ R ８ O ２／２ ] units (preferably D units), [SiR ９ O ３／２ ] units (preferably T units) and [SiO ４／２ ] (Q unit). ７ , R ８ and R ９ are each independently a hydrocarbon group. ７ , R ８ and R ９ and R when it is a hydrocarbon group. １ For example, [SiR ７ R ８O ２／２ ] units, and can have a linear structure composed only of [SiR ７ O ３／２ By including the [SiR] unit, a branched or cyclic structure can be obtained, and by including the Q unit, a three-dimensional network structure can be obtained. ７ R ８ O ２／２ ] units, [SiR ９ O ３／２ The finite number of combinations of [SiR] units and Q units include at least two bond sites, but the site where the siloxane skeleton is bonded to another group may be located in any part of each unit constituting the siloxane skeleton. ７ R ８ O ２／２ ] units form a cyclic structure, the group R ７ or R ８ serves as a bond and can be linked to other groups. For example, a group having a cyclic siloxane skeleton is [SiR ７ R ８ O ２／２ ] At least two groups R ７ is a bond to a hydrocarbon group such as an ethylene group, the following structure is preferred. (In the formula, the wavy line portion represents the portion bonding to the silicon atom to which the hydrolyzable group is bonded, the benzimidazolidinone portion, and the optionally present group (e.g., the carbon atom of the alkylene group).)

[0058] The siloxane chain is preferably a divalent or higher group because it can function as a spacer (linking group) between the benzimidazolidinone moiety and the hydrolyzable silyl group, or as a spacer between two benzimidazolidinone moieties.

[0059] Other groups include X １ ~X ３ Examples include:

[0060] Component (C) preferably contains one or two benzimidazolidinone moieties per molecule, and particularly preferably contains one or two benzimidazolidinone moieties, a siloxane chain, and a hydrolyzable group bonded to a silicon atom per molecule.

[0061] Component (C) is preferably a compound represented by general formula (1), (2) or (3).

[0062] <Compound Represented by General Formula (1)> The compound represented by general formula (1) is as follows. [In the formula, A １ , X １ , R １ is as described above.

[0063] The compound represented by general formula (1) is a compound containing one benzimidazolidinone moiety, a hydrolyzable group bonded to a silicon atom, and optionally a siloxane chain in one molecule.

[0064] A １ is expressed by formula (4) or (5): [In the formula, R ２１ , R ２２ and R ２３ is as defined above.

[0065] R ２１ is a hydrogen atom or a hydrocarbon group. ２１ When R is a hydrocarbon group, it is preferably an alkyl group, and particularly preferably a methyl group. ２１ is preferably a hydrogen atom or a methyl group.

[0066] R ２２ and R ２３ are each independently a hydrogen atom or a hydrocarbon group. ２２ and R ２３ is R ２１ Therefore, R ２２ and R ２３ are preferably each independently a hydrogen atom or a methyl group.

[0067] Also, A １may be a group represented by the following formula (4-1) or (5-1).

[0068] X １ is an alkylene group which may be interrupted by —S—, an alkylene group which may be interrupted by —NH—, or an alkylene group which may be interrupted by a linear or cyclic siloxane chain. １ may be an alkylene group which may be interrupted by -S-, or an alkylene group which may be interrupted by a linear or cyclic siloxane chain. １ The structure represented by the formula: １ (i.e., a benzimidazolidinone moiety represented by formula (4) or (5)) and a hydrolyzable silyl group (i.e., a group: —SiR １ ３ ) is a moiety that acts as a spacer for the group represented by X １ The structure of the alkylene group in X may be linear, branched, cyclic, or a combination thereof, and is preferably linear. １ The alkylene group in the formula (I) preferably has 1 to 20 carbon atoms, and particularly preferably has 1 to 6 carbon atoms.

[0069] R １ are each independently a hydrolyzable group or a hydrocarbon group, provided that at least one R １ is a hydrolyzable group. Here, the hydrolyzable group is as described in component (A). １ In addition, in view of curability, in the general formula (1), all of R １ is preferably a hydrolyzable group.

[0070] <Compound Represented by General Formula (2)> The compound represented by general formula (2) is as follows. [In the formula, A ２ , A ３ , X ２ , X ３ , R ２ , R ３ , L １ is as described above.

[0071] The compound represented by general formula (2) is a compound containing two benzimidazolidinone moieties, a hydrolyzable group bonded to a silicon atom, and optionally a siloxane chain in one molecule. １ is 1 or more, the compound represented by general formula (2) is a compound containing two benzimidazolidinone moieties, a siloxane chain, and a hydrolyzable group bonded to a silicon atom in one molecule.

[0072] A ２ and A ３ A １ It is synonymous with X. ２ and X ３ is X １ Also, R ２ is R １ From the viewpoint of curability, all R ２ is preferably a hydrolyzable group. ３ is R when it is a hydrocarbon group １ is synonymous with.

[0073] L １ is (R ３ ) ２ SiO ２／２ is the repeating number of the siloxane chain composed of units. １ is 0 or a number from 1 to 1,000, preferably 0 or a number from 1 to 300, and particularly preferably 0 or a number from 1 to 150.

[0074] <Compound Represented by General Formula (3)> The compound represented by general formula (3) is as follows. [In the formula, A ４ , X ４ , X ５ , R ４ , R ５ , a, b, and c are as defined above.

[0075] The compound represented by the general formula (3) is a compound containing one or more benzimidazolidinone moieties, a hydrolyzable group bonded to a silicon atom, and an alkylene group interrupted by a cyclic siloxane chain in one molecule. ４ and X ５form an alkylene group, which is interrupted by cyclic siloxanes bounded by a, b, and c.

[0076] A ４ A １ It is synonymous with R ４ is R when it is a hydrocarbon group １ Also, R ５ is R １ From the viewpoint of curability, in general formula (3), all of R ５ is preferably a hydrolyzable group.

[0077] X ４ and X ５ is X １ It is synonymous with X. ４ and X ５ is preferably an uninterrupted alkylene group. ４ and X ５ The alkylene group in the formula (I) preferably has 1 to 20 carbon atoms, and particularly preferably has 1 to 6 carbon atoms.

[0078] a is an integer of 1 or more. From the viewpoint of corrosion resistance, a is preferably an integer of 1 to 3, and particularly preferably an integer of 1 to 2. When a is an integer of 2 or more, each A ４ , X ４ and R ４ are preferably the same.

[0079] b is 0 or an integer of 1 or more. When b is an integer of 1 or more, the compound represented by general formula (3) contains a hydrolyzable group bonded to a silicon atom. From the viewpoint of curability, b is preferably an integer of 1 to 3, and particularly preferably an integer of 1 to 2. When b is an integer of 2 or more, each X ５ , R ４ and R ５ are preferably the same.

[0080] c is an integer of 0 or 1 or more. From the viewpoint of ease of synthesis and handling, c is preferably 0 or an integer of 1 to 3, and particularly preferably 0 or an integer of 1 to 2. When c is an integer of 2 or more, each R ４are preferably the same.

[0081] Furthermore, a+b+c is an integer of 3 or greater. When a+b+c is an integer of 3 or greater, the main skeleton becomes a cyclic organosiloxane. From the viewpoint of ease of synthesis, a+b+c is preferably an integer of 3 to 8, and particularly preferably an integer of 4 to 6.

[0082] Component (C) is preferably one or more compounds selected from the group consisting of Compounds 1 to 9 in the Examples.

[0083] Component (C) may be a single component or a combination of two or more components.

[0084] <Method for producing component (C)> Component (C) can be obtained by reacting a salt of benzimidazolidinone or a salt of 5-amino-2-benzimidazolidinone with a silane compound. Specifically, component (C) can be obtained by reacting a siloxane having a halogenated alkyl group with benzimidazolidinone or a salt of 5-amino-2-benzimidazolidinone.

[0085] The quantitative ratio of the benzimidazolidinone salt or 5-amino-2-benzimidazolidinone salt to the siloxane having a halogenated alkyl group can be set as appropriate, but the amount of the siloxane having a halogenated alkyl group relative to the benzimidazolidinone salt or 5-amino-2-benzimidazolidinone salt is preferably 0.5 to 1.5 mol, and particularly preferably 0.8 to 1.2 mol.

[0086] In the method for producing component (C), a solvent may be used as needed. There are no particular limitations on the solvent, so long as it is non-reactive with the raw material compounds. Examples of the solvent include aliphatic hydrocarbon solvents such as pentane, hexane, heptane, and cyclohexane; ether solvents such as diethyl ether, tetrahydrofuran, and 1,4-dioxane; halogenated solvents such as chloroform and dichloromethane; amide solvents such as formamide, dimethylformamide, and N-methylpyrrolidone; and aromatic hydrocarbon solvents such as benzene, toluene, and xylene.

[0087] In the method for producing component (C), the reaction temperature and reaction time can be set appropriately. When a solvent is used, the reaction temperature can be in the range of room temperature (23°C) to the boiling point of the solvent. The reaction time is preferably 1 to 12 hours and can be set appropriately depending on the reaction temperature.

[0088] [Additional Components] The composition may contain additional components as long as the effects of the present invention are achieved. Examples of additional components include (D) a crosslinking agent, (E) an adhesion promoter, (F) a polyorganosiloxane that does not have a silicon-bonded hydrolyzable group, and a component (G) other than components (D) to (F). Components (D) to (F) exclude components corresponding to components (A) to (C).

[0089] <(D) Crosslinking Agent> Component (D) is a crosslinking agent. Examples of component (D) include an organosilicon compound having at least two hydrolyzable groups bonded to a silicon atom, or a partial hydrolysis condensate thereof. Here, the organosilicon compound is preferably a compound having one silicon atom per molecule. Component (D) is a compound that undergoes a crosslinking reaction (condensation reaction) with component (A), specifically, with the hydrolyzable group bonded to the silicon atom of component (A). Component (D) does not have any reactive functional groups other than the hydrolyzable group. Here, examples of the reactive functional group include a primary amino group, an epoxy group, a (meth)acryloyl group, a (meth)acryloxy group, a mercapto group, and an isocyanato group.

[0090] Component (D) is R １０ ｕ Si(OR １１ ) ４-ｕ (In the formula, R １０ is independently in each occurrence an unsubstituted or substituted monovalent hydrocarbon group; R １１ is preferably an organosilicon compound represented by the formula (I) or a partial hydrolysis condensate thereof, wherein each occurrence of each group independently represents an unsubstituted or substituted monovalent hydrocarbon group, and u is 0, 1, or 2.

[0091] R １０is preferably an unsubstituted or halogen-substituted alkyl, cycloalkyl, aryl, aralkyl or alkenyl group.

[0092] R １１ is preferably an alkyl group having 1 to 3 carbon atoms, and CH ３ - or C ２ H ５ It is particularly preferred that -.

[0093] Preferably, u is 1 or 2.

[0094] It is particularly preferred that component (D) is an alkoxy group-containing compound selected from the group consisting of tetramethoxysilane, methyltrimethoxysilane, vinyltrimethoxysilane, decyltrimethoxysilane, phenyltrimethoxysilane, tetraethoxysilane, methyltriethoxysilane, vinyltriethoxysilane, phenyltriethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, dimethyldimethoxysilane, vinylmethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, and 3-chloropropyltrimethoxysilane; a partial hydrolysis condensate of the alkoxy group-containing compound; or a combination thereof.

[0095] Component (D) may be a single component or a combination of two or more components.

[0096] <(E) Adhesion Promoter> Component (E) is an adhesion promoter. Component (E) is a component that improves the adhesion of a cured product of the composition to substrates such as metals, glass, and plastics. Examples of component (E) include compounds having a silicon-bonded hydrolyzable group and a reactive organic functional group, and / or partial hydrolysis condensates of the above compounds (excluding those corresponding to components (A) to (C)). Here, examples of the reactive organic functional group include a primary amino group, an epoxy group, a (meth)acryloyl group, a (meth)acryloxy group, a mercapto group, and an isocyanato group.

[0097] Specific examples of component (E) include alkoxysilyl group-containing isocyanurate compounds, alkoxysilyl group-containing carbasilatrane compounds, alkoxysilyl group-containing fumaric acid ester compounds, and alkoxysilyl group-containing amine compounds.

[0098] Examples of the alkoxysilyl group-containing isocyanurate compound include tris[(3-trialkoxysilyl)propyl]isocyanurates such as tris[(3-trimethoxysilyl)propyl]isocyanurate and tris[(3-triethoxysilyl)propyl]isocyanurate.

[0099] Examples of alkoxysilyl group-containing fumaric acid ester compounds include bis(3-trimethoxysilylpropyl)fumarate, bis(3-triethoxysilylpropyl)fumarate, etc. Examples of alkoxysilyl group-containing amine compounds include bis(3-trimethoxysilylpropyl)amine, bis(3-triethoxysilylpropyl)amine, tris(3-trimethoxysilylpropyl)amine, tris(3-triethoxysilylpropyl)amine, etc.

[0100] Examples of the alkoxysilyl group-containing epoxy compound include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3,4-epoxycyclohexylethyltrimethoxysilane.

[0101] Component (E) may be a single component or a combination of two or more components.

[0102] <(F) Polyorganosiloxane without a silicon-bonded hydrolyzable group> Component (F) is a polyorganosiloxane without a silicon-bonded hydrolyzable group. When the composition contains component (F), the hardness of the cured product of the composition and / or the viscosity of the composition tend to be controlled. In addition, when the composition contains component (F), the handleability of the composition and the required physical properties can be widely accommodated.

[0103] Examples of component (F) include siloxane resins such as polydimethylsiloxane that do not have a curable functional group. Examples of the siloxane resin of component (F) include resins obtained by combining the M unit, D unit, T unit, and / or Q unit and that do not have a hydrolyzable group.

[0104] Component (F) is a compound represented by the following general formula (7): ６ ３ Si—O—(SiR ６ ２ O) ｖ -SiR ６ ３ (7) (wherein, R ６ is as defined in general formula (6), and v is a number that provides a viscosity at 23°C of 1 mPa·s to 10,000 mPa·s.

[0105] The viscosity of component (F) is preferably 1 mPa s to 10,000 mPa s, and particularly preferably 1 mPa s to 1,000 mPa s, at 23° C. When the viscosity of component (F) is within this range, viscosity adjustment can be carried out more efficiently.

[0106] Component (F) may be a single component or a combination of two or more components.

[0107] <Component (G) Other Than Components (D) to (F)> Examples of component (G) include inorganic fillers, flame retardants, heat resistance imparting agents, organic solvents, inorganic pigments, organic pigments, etc. Component (G) may be a single component or a combination of two or more components.

[0108] It is preferred that the composition further comprises one or more members selected from the group consisting of (D) a crosslinking agent, (E) an adhesion promoter, and (F) a polyorganosiloxane having no silicon-bonded hydrolyzable groups.

[0109] <Content of Each Component> In the composition, the content of each component is preferably as follows.

[0110] The content of component (A) is not particularly limited as long as it is an amount that allows the curable polyorganosiloxane composition to have a handleable viscosity range. The content of component (A) is preferably 50.0 to 99.9 parts by mass, more preferably 70.0 to 98.0 parts by mass, and particularly preferably 80.0 to 95.0 parts by mass, per 100 parts by mass of the total of components (A), (B), and (C).

[0111] The content of component (B) is a catalytic amount relative to the total amount of the curable polyorganosiloxane composition. From the viewpoint of curability, the content of component (B) is preferably 0.01 to 10.0 parts by mass, particularly preferably 0.03 to 5.0 parts by mass, relative to 100 parts by mass of component (A).

[0112] From the viewpoint of corrosion prevention, the content of component (C) is preferably 0.1 to 30.0 parts by mass, more preferably 0.2 to 20.0 parts by mass, and particularly preferably 0.3 to 10.0 parts by mass, per 100 parts by mass of component (A).

[0113] The total content of components (A) to (C) relative to the total amount of the composition is preferably 50 to 100 parts by mass, more preferably 75 to 100 parts by mass, and particularly preferably 80 to 100 parts by mass.

[0114] From the viewpoints of storage stability and curability, the content of component (D) is preferably 0 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, and particularly preferably 0.5 to 15 parts by mass, per 100 parts by mass of component (A).

[0115] Component (D) can contain, for example, 1 to 30 moles, and specifically 2 to 20 moles, of hydrolyzable groups of component (D) per mole of hydrolyzable groups bonded to silicon atoms of component (A).

[0116] From the viewpoint of exhibiting higher adhesiveness to the substrate, the content of component (E) is preferably 0 to 20 parts by mass, more preferably 0.05 to 20 parts by mass, even more preferably 0.1 to 15 parts by mass, and particularly preferably 0.5 to 10 parts by mass, per 100 parts by mass of component (A).

[0117] From the viewpoint of coating performance, the content of component (F) is preferably 0 parts by mass or more and 50 parts by mass or less, more preferably 0.1 to 50 parts by mass, and particularly preferably 1 to 30 parts by mass, per 100 parts by mass of component (A).

[0118] The content of component (G) is not particularly limited as long as it does not impair the intended use of the curable polyorganosiloxane composition.

[0119] [Method for producing curable polyorganosiloxane composition] The curable polyorganosiloxane composition can be produced by uniformly kneading components (A) to (C) and optional components (D) to (F) using a mixing means such as a universal mixer or kneader.

[0120] [Uses of the curable polyorganosiloxane composition] The curable polyorganosiloxane composition can be used as a metal surface treatment agent. Examples of metals include aluminum, copper, nickel, iron, brass, stainless steel, etc. The curable polyorganosiloxane composition can also be used as a coating agent for electronic components.

[0121] [Cured product of curable polyorganosiloxane composition] A cured product obtained by curing the curable polyorganosiloxane composition can be obtained by curing the curable polyorganosiloxane composition. As for curing conditions, if the thickness is about 0.1 mm, curing can be accelerated by heating at room temperature (20 to 30 ° C) for 2 to 4 hours, and if necessary, at 30 to 60 ° C. Preferred curing conditions are room temperature (20 to 30 ° C) and relative humidity: 40 to 60% RH.

[0122] The cured product obtained by curing the curable polyorganosiloxane composition can be used as a surface coating for metals. The cured product obtained by curing the curable polyorganosiloxane composition can also be used as a coating for electronic components such as electronic devices and integrated circuit elements. Therefore, electronic components containing the curable polyorganosiloxane composition are also within the scope of the present invention.

[0123] [Article containing a cured product of the curable polyorganosiloxane composition] The article containing the cured product of the curable polyorganosiloxane composition is preferably an article containing a substrate and a cured product of the composition. Examples of articles containing a substrate and a cured product of the composition include electronic devices, integrated circuit elements, and other electronic components.

[0124] The method for producing the article is not particularly limited, and preferably includes the steps of preparing a part including a substrate and a composition, applying the composition to a surface of the substrate, and curing the composition to form a cured product of the composition on the substrate.

[0125] Examples of the substrate include, in addition to metals, epoxy resins, polyester resins such as polyethylene terephthalate and polybutylene terephthalate (PBT) resins, engineering plastics such as polycarbonate resins, acrylic resins, polyimide resins, phenolic resins, polyamide resins, polyphenylene sulfide (PPS) resins, and modified polyphenylene ether (PPE) resins; and glass. If necessary, the wall surfaces of the gaps may be subjected to a primer treatment according to a conventional method. The shape, thickness, etc. of the substrate are not particularly limited.

[0126] Methods for applying the curable polyorganosiloxane composition include dripping, pouring, casting, extrusion from a container, coating such as bar coating or roll coating, screen printing, dipping, brushing, spraying, and dispensing. The composition may be applied uniformly over the entire surface of the part, or unevenly or partially, such as in lines, stripes, or dots. The application thickness of the composition is preferably 0.01 to 3 mm, and particularly preferably 0.05 to 2 mm.

[0127] The curing conditions for the composition are as described above for the cured product of the composition.

[0128] [(C) Compound containing a benzimidazolidinone moiety and a hydrolyzable group bonded to a silicon atom in one molecule] Another aspect of the present invention is a compound (C) containing a benzimidazolidinone moiety and a hydrolyzable group bonded to a silicon atom in one molecule (hereinafter, sometimes referred to as "compound (C)"). Compound (C), including preferred embodiments, is as described above for component (C). Therefore, compound (C) is preferably a compound containing one or two benzimidazolidinone moieties, a siloxane chain, and a hydrolyzable group bonded to a silicon atom in one molecule. Furthermore, compound (C) is particularly preferably a compound represented by general formula (1), (2), or (3).

[0129] Compound (C) can impart excellent corrosion resistance and uniformity to the curable silicone composition. Therefore, compound (C) can be used as an agent for improving corrosion resistance and uniformity for the second curable polyorganosiloxane composition. Here, the second curable polyorganosiloxane composition contains component (A) and component (B), and optionally contains one or more selected from the group consisting of component (D), component (E), component (F) and component (G). Each component and its content, including preferred embodiments, are as described above in the curable polyorganosiloxane composition.

[0130] The present invention will be described in more detail below with reference to examples and comparative examples. In these examples, parts refer to parts by mass, and viscosity refers to viscosity at 23° C. The present invention is not limited to these examples.

[0131] <Ingredients used> Component (A): α,ω-bis(trimethoxysiloxy)polydimethylsiloxane (viscosity 300 mPa·s) Component (B): diisopropoxybis(ethylacetoacetate)titanium Component (C): Compounds 1 to 9 Component (D): methyltrimethoxysilane Component (E): tris[(3-trimethoxysilyl)propyl]isocyanurate Component (F): polydimethylsiloxane (viscosity 1 mPa·s)

[0132] Comparative component (C'): 2-hydroxybenzimidazole 1-isopropenyl-2-benzimidazolidinone 1-(3-chloropropyl)-1,3-dihydro-2H-benzimidazol-2-one 1,2,3-benzotriazole

[0133] (Production of Component (C) (Compounds 1 to 9))

[0134] <Compound 1> 800 g of xylene, 94 g (0.7 mol) of 2-hydroxybenzimidazole, and 8.5 g of a basic catalyst were added to a 2,000 ml flask equipped with a nitrogen gas inlet tube and a condenser, followed by the addition of 131 g (0.66 mol) of 3-chloropropyltrimethoxysilane, and the mixture was stirred under a nitrogen stream at 120° C. for 8 hours. After cooling, the mixture was filtered, and the xylene and excess materials were distilled off at 135° C. to obtain 171 g of Compound 1. １ Analysis by H-NMR revealed the following, confirming that the compound was the target compound.

[0135] NH: 10.8ppm, C ６ H ４ :6.9ppm to 7.2ppm, -Si(OCH ３ ): 3.5ppm, N-CH: 4.6ppm, Si-CH ２ -:0.5-0.7ppm, Si-CH ２ -CH ２ -: 1.6 to 1.8 ppm, Si-CH ２ -CH ２ -CH ２ -: 2.3 to 2.6 ppm

[0136]

[0137] <Compound 2> A 1,000 ml flask equipped with a nitrogen gas inlet tube and a condenser was charged with 600 g of tetrahydrofuran, 89 g (0.51 mol) of 1-isopropenyl-2-benzimidazolidinone, 110.3 g (0.56 mol) of 3-mercaptopropyltrimethoxysilane, and 0.5 g of AIBN (azobisisobutyronitrile), and the mixture was heated and stirred for 7 hours at 60° C. Tetrahydrofuran, excess materials, etc. were removed by heating at 130° C. under reduced pressure, yielding 248 g of Compound 2.１ Analysis by H-NMR revealed the following, confirming that the compound was the target compound.

[0138] NH: 10.8ppm, C ６ H ４ :6.9ppm to 7.2ppm, -Si(OCH ３ ): 3.5ppm, N-CH: 4.6ppm, N-CH(CH ３ ): 1.4ppm, N-CH(CH ３ )-CH ２ :2.9~3.2ppm, S-CH ２ -:2.4ppm, S-CH ２ -CH ２ -: 1.6ppm, S-CH ２ -CH ２ -CH ２ -: 0.6 ppm,

[0139]

[0140] <Compound 3> A 2,000 ml flask equipped with a nitrogen gas inlet tube and a condenser was charged with 800 g of xylene, 169 g (0.8 mol) of 1-(3-chloropropyl)-1,3-dihydro-2H-benzimidazol-2-one, and 9.0 g of an amine catalyst, followed by 158 g (0.88 mol) of 3-aminopropyltrimethoxysilane, and the mixture was stirred at 80° C. for 6 hours under a nitrogen stream. Distillation was performed to remove unreacted excess material, yielding 206 g of Compound 3. １ Analysis by H-NMR revealed the following, confirming that the compound was the target compound.

[0141] NH: 10.8ppm, C ６ H ４ :6.9ppm to 7.2ppm, -Si(OCH ３ ): 3.5ppm, N-CH: 4.6ppm, Si-CH ２ -: 0.5 to 0.7 ppm, Si-CH ２ -CH ２ -: 1.6 to 1.8 ppm, Si-CH ２ -CH ２ -CH ２ -: 2.3 to 2.6 ppm

[0142]

[0143] <Compound 4> A 2,000 ml flask equipped with a nitrogen gas inlet tube and a condenser was charged with 1,200 g of xylene, 113 g (0.84 mol) of 2-hydroxybenzimidazole, and 110 g (0.4 mol) of 1-(1-chloromethyl)-3-(2-trimethoxysilylethyl)-1,1,3,3-tetramethyldisiloxane, and the mixture was heated and stirred for 4 hours at 80° C. After cooling, the mixture was filtered, and the xylene and excess materials were distilled off at 135° C., yielding 140 g of Compound 4. １ Analysis by H-NMR revealed the following, confirming that the compound was the target compound.

[0144] NH: 10.8ppm, C ６ H ４ :7.1ppm to 7.8ppm, -Si(OCH ３ ): 3.5ppm, Si-CH ２ -CH ２ -Si: 0.5 to 1 ppm, Si-CH ２ -N: 0.6 to 0.8 ppm, CH ３ -Si-CH ３ :-0.2ppm~0.2ppm

[0145]

[0146] <Compound 5> A 2,000 ml flask equipped with a nitrogen gas inlet tube and a condenser was charged with 800 g of xylene, 120 g (0.8 mol) of 5-amino-1,3-dimethyl-1,3-dihydro-2H-benzimidazol-2-one, and 149 g (0.75 mol) of trimethoxysilylpropyl chloride, and heated under a nitrogen stream at 80° C. for 8 hours and at 120° C. for 2 hours. After filtration, the xylene and excess trimethoxysilylpropyl chloride were removed by thermal stripping under reduced pressure, yielding 196 g of Compound 5. １ Analysis by H-NMR revealed the following, confirming that the compound was the target compound.

[0147] NH: 10.8ppm, C ６ H ４ :6.8ppm to 7.2ppm, -Si(OCH ３): 3.3ppm, C ６ H ３ -NH: 3.5-3.7ppm, N-CH: 4.4ppm, N-CH ２ -CH ２ -CH ２ :3.5~3.8ppm, N-CH ２ -CH ２ -CH ２ :2.8~3.1ppm

[0148]

[0149] <Compound 6> A 1,000 ml flask equipped with a nitrogen gas inlet tube and a condenser was charged with 500 g of xylene, 76 g (1.0 mol) of allyl chloride, and 186.5 g (0.95 mol) of 3-mercaptopropyltrimethoxysilane, and 0.5 g of AIBN was added under a nitrogen stream, followed by heating and stirring at 60° C. for 7 hours. Excess materials were removed, yielding 248 g of Intermediate Compound 1.

[0150] A 2000 ml flask equipped with a nitrogen gas inlet tube and a condenser was charged with 800 g of xylene and 120 g (0.8 mol) of 5-amino-1,3-dimethyl-1,3-dihydro-2H-benzimidazol-2-one, and then 204 g of the intermediate compound described above was added thereto, followed by heating under a nitrogen stream at 80° C. for 8 hours and at 120° C. for 2 hours. After filtration, the xylene, unreacted material, and excess material were removed by thermal stripping under reduced pressure, yielding 262 g of Compound 6. １ Analysis by H-NMR revealed the following, confirming that the compound was the target compound.

[0151] NH: 10.8ppm, C ６ H ４ :6.8ppm to 7.2ppm, -Si(OCH ３ ): 3.3ppm, C ６ H ３ -NH: 3.5-3.7ppm, N-CH: 4.4ppm, N-CH ２ -CH ２ -CH ２ :3.5~3.8ppm, N-CH ２ -CH ２ -CH ２ :2.8~3.1ppm, S-CH２ :2.3ppm, S-CH ２ -CH ２ :1.4ppm, S-CH ２ -CH ２ -CH ２ : 0.6 ppm

[0152]

[0153] <Compound 7> A 2,000 ml flask equipped with a nitrogen gas inlet tube and a condenser was charged with 1,200 g of xylene, 113 g (0.84 mol) of 2-hydroxybenzimidazole, and 296 g (0.4 mol) of α,ω-bis(1-chloromethyldimethoxysilyl)-1,1,3,3,5,5,7,7,9,9,11,11-dodecamethylhexasiloxane, and the mixture was heated and stirred at 80°C for 4 hours. The mixture was then treated with activated carbon and filtered. The xylene was then distilled off, yielding 368 g of Compound 7. １ Analysis by H-NMR revealed the following, confirming that the compound was the target compound.

[0154] NH: 10.8ppm, C ６ H ４ :6.8ppm to 7.2ppm, -Si(OCH ３ ): 3.3ppm, N-CH ２ :3.8~4.4ppm, CH ３ -Si-CH ３ :-0.2ppm to 0.2ppm, Si-CH ２ -:0.6~0.8ppm

[0155]

[0156] <Compound 8> 100 g of α,ω-dihydroxydodecamethylhexasiloxane, 196.3 g (1.0 mol) of 3-mercaptopropyltrimethoxysilane, and 0.5 g of a condensation catalyst were placed in a 1,000 ml flask equipped with a nitrogen gas inlet tube and a condenser, and the mixture was heated and stirred at 80°C for 4 hours to obtain 139 g of a siloxane oligomer containing terminal mercaptopropyl groups, as an intermediate compound.

[0157] A 1,000 ml flask equipped with a nitrogen gas inlet tube and a condenser was charged with 300 g of tetrahydrofuran, 41 g (0.52 mol) of 1-isopropenyl-2-benzimidazolidinone, 85 g of the intermediate compound (mercaptopropyl-terminated siloxane oligomer) and 0.5 g of AIBN, and the mixture was heated and stirred at 60° C. for 7 hours. Tetrahydrofuran and the like were removed by heating at 130° C. under reduced pressure, yielding 119 g of Compound 8. １ Analysis by H-NMR revealed the following, confirming that the compound was the target compound.

[0158] NH: 10.8ppm, C ６ H ４ :6.8ppm to 7.2ppm, -Si(OCH ３ ): 3.3ppm, N-CH: 4.4ppm, N-CH(CH ３ ): 1.4ppm, N-CH(CH ３ )-CH ２ :2.8~3.1ppm, S-CH ２ :2.3ppm, S-CH ２ -CH ２ :1.4ppm, S-CH ２ -CH ２ -CH ２ :0.6ppm, CH ３ -Si-CH ３ :-0.2ppm~0.2ppm

[0159]

[0160] <Compound 9> A 1,000 ml flask equipped with a nitrogen gas inlet tube and a condenser was charged with 400 g of toluene, 108 g (0.7 mol) of 1,1,3,5,7-pentamethylcyclotetrasiloxane, and 1.54 g of an alumina-supported platinum catalyst, and 54 g (0.7 mol) of allyl chloride was added dropwise over approximately 1 hour. The temperature was raised to 120°C under a nitrogen stream. The mixture was then reacted at 105°C for 4 hours, yielding reaction solution 1.

[0161] The resulting reaction solution 1 was cooled to room temperature, and 118 g (0.8 mol) of vinyltrimethoxysilane was added dropwise over approximately 1 hour. The temperature was raised to 120°C under a nitrogen stream. The reaction was then carried out at 105°C for 4 hours to obtain reaction solution 2. The resulting reaction solution 2 was cooled to room temperature, and then 108 g (0.8 mol) of 2-hydroxybenzimidazole was added, followed by heating and stirring at 80°C for 4 hours. After cooling, the solution was filtered, and toluene and excess materials were distilled off under reduced pressure and concentrated to obtain 303 g of compound 9. １ Analysis by H-NMR revealed the following, confirming that the compound was the target compound.

[0162] C ６ H ４ :6.8ppm to 7.2ppm, -Si(OCH ３ ): 3.3ppm, N-CH ２ -CH ２ -CH ２ :2.8~3.1ppm, -Si-CH ２ -CH ２ -Si(OCH ３ ) ３ :0.5~1ppm, Si-CH ３ :0.1ppm~0.2ppm, Si-CH ２ -:0.5-0.7ppm, Si-CH ２ -CH ２ -: 1.6 to 1.8 ppm, Si-CH ２ -CH ２ -CH ２ -: 2.3 to 2.6 ppm

[0163]

[0164] (Preparation of Curable Silicone Compositions) Curable polyorganosiloxane compositions were prepared by mixing the components according to the formulations shown in Tables 1 to 3.

[0165] (Evaluation Method) <Appearance> After preparation, the polyorganosiloxane composition was stored at room temperature (23°C) for 7 days or at 5°C for 3 days, and the appearance (uniformity and coloration) was evaluated. The appearance was evaluated by visually inspecting the composition. The uniformity of the composition was evaluated on the following four-point scale. The larger the value, the higher the evaluation of the uniformity of the composition. Furthermore, the coloration of the composition was evaluated on the following two-point scale. The smaller the value, the less coloration of the composition. Evaluation of uniformity 4: transparent 3: transparent to translucent 2: translucent 1: not dissolved or precipitated Evaluation of coloration 2: pale yellow 1: slightly pale yellow

[0166] <Viscosity> The viscosity of the polyorganosiloxane composition was measured at 23°C using a VISCOMETER TVB-10M manufactured by Toki Sangyo Co., Ltd. The rotor used was TM2, and the viscosity was measured under conditions of 60 pm and 1 minute value.

[0167] <Tack-free time> The polyorganosiloxane composition was applied to a thickness of 100 μm on the surface of an aluminum petri dish having a diameter of 5 cm, the surface of which had been cleaned with an organic solvent. The time (minutes) until the composition was confirmed to be dry after touching the surface with a finger under an environment of 23°C and a relative humidity (RH) of 50% was measured.

[0168] <Heat Resistance> Heat resistance was evaluated by placing copper foil coated with a polyorganosiloxane composition in an atmosphere at 150°C for 30 minutes or in an atmosphere at 85°C and 85% RH for 24 hours. The evaluation was performed by visually judging the change in color tone of the coating film, and was evaluated on the following five-point scale. The higher the value, the higher the heat resistance. 5: Almost no change 4: Slight discoloration 3: Yellowing 2: Orange 1: Dark brown

[0169] <Heat Cycle Test (Reliability)> Copper foil coated with a polyorganosiloxane composition was placed in an atmosphere in which the temperature changed from -40 to 125°C over the course of one hour, and this cycle was repeated 250 times. One cycle consisted of a change from -40°C to 125°C in 30 minutes, and a change from 125°C to -40°C in 30 minutes. Evaluation was performed by visually judging whether cracks occurred in the coating film, and was rated on the following five-point scale. The higher the value, the better the reliability. 5: No change 4: Some fine cracks 3: Fine cracks 2: Cracks 1: Large cracks

[0170] <Corrosion resistance> The polyorganosiloxane composition was applied to a copper plate (JIS H 3100: C1100P) whose surface had been polished with 4,000 mesh abrasive paper to a thickness of 100 μm and then cleaned, and the applied coating was left in an atmosphere of 23° C. and 50% RH for 3 days to obtain a sample. The obtained sample was used to test for corrosion resistance (saltwater resistance) and corrosion resistance (sulfur resistance).

[0171] <<Corrosion Prevention (Sulfur Resistance)>> 0.2 g of sulfur and 5 g of water were placed in a 100 ml glass bottle to obtain a sulfur-containing aqueous solution. The obtained sample was immersed in the sulfur-containing aqueous solution and, after 10 days at 80°C, dried at room temperature (23°C) for 7 days, and then the condition of the substrate (discolored location, color, and area ratio) was confirmed. The area ratio of the discolored portion was evaluated according to the "Corrosion Prevention Evaluation Criteria" below. The higher the value, the higher the evaluation of corrosion prevention (sulfur resistance).

[0172] <<Corrosion resistance (saltwater resistance)>> The obtained samples were immersed in a 5 wt % sodium chloride aqueous solution (saltwater), left at 50°C for 7 days, and then dried at room temperature (23°C) for a further 7 days, after which the condition of the substrate (proportion of discolored area) was confirmed. The proportion of the discolored area was evaluated according to the "Corrosion resistance evaluation criteria" below. The higher the value, the higher the evaluation of corrosion resistance (saltwater resistance).

[0173] <Evaluation criteria for corrosion resistance> 10: 0-9% 9-10: Over 9% and up to 15% 9: Over 15% and up to 20% 8: Over 20% and up to 30% 7: Over 30% and up to 40% 6: Over 40% and up to 50% 5: Over 50% and up to 60% 4: Over 60% and up to 70% 3: Over 70% and up to 80% 2: Over 80% and up to 90% 1: Over 90% and up to 100%

[0174] The results are summarized in Tables 1 to 3.

[0175]

[0176]

[0177]

[0178] As can be seen from Tables 1 and 2, the compositions of the Examples had excellent corrosion prevention properties and uniformity. In particular, a comparison of Examples 1 to 4 and 6 to 7 with Examples 5 and 8 to 13 shows that saltwater resistance was superior when component (C) was a compound containing, in one molecule, a benzimidazolidinone moiety, a siloxane chain, and a hydrolyzable group bonded to a silicon atom.

[0179] Comparative Example 1 does not contain a component corresponding to compound (C). Comparative Examples 2 to 7 contain benzotriazole, imidazole, or the like, which are used as conventional rust inhibitors, as a component corresponding to compound (C). Comparative Example 8 does not use a composition.

[0180] The compositions of Comparative Examples 2 to 5 were poor in uniformity and saltwater resistance. In particular, the compositions of Comparative Examples 2 and 4 to 5 exhibited precipitation of benzotriazole, imidazole, etc., and the uniformity of the composition was significantly poor. The composition of Comparative Example 3 exhibited precipitation of 1-isopropenyl-2-benzimidazolidinone after storage at 5°C, and the uniformity of the composition was significantly poor. Furthermore, the compositions of Comparative Examples 1 and 6 to 7 exhibited poor corrosion prevention properties. Furthermore, the saltwater resistance result of Comparative Example 8, which did not use a composition, showed significant corrosion.

Claims

1. A curable polyorganosiloxane composition comprising: (A) a polyorganosiloxane having two or more silicon-bonded hydrolyzable groups per molecule and no benzimidazolidinone moieties; (B) a curing catalyst; and (C) a compound containing a benzimidazolidinone moiety and a silicon-bonded hydrolyzable group per molecule.

2. The curable polyorganosiloxane composition according to claim 1, wherein component (C) is a compound containing, in one molecule, one or two benzimidazolidinone moieties, a siloxane chain, and a hydrolyzable group bonded to a silicon atom.

3. Component (C) is a compound represented by the following general formula (1), (2), or (3): [In the formula, A １ is expressed by formula (4) or (5): (In formula (4), R ２１ is a hydrogen atom or a hydrocarbon group) (In formula (5), R ２２ and R ２３ are each independently a hydrogen atom or a hydrocarbon group, １ is an alkylene group which may be interrupted by —S—, an alkylene group which may be interrupted by —NH—, or an alkylene group which may be interrupted by a linear or cyclic siloxane chain, and R １ are each independently a hydrolyzable group or a hydrocarbon group, provided that at least one R １ is a hydrolyzable group. [In the formula, A ２ and A ３ are each independently a group represented by formula (4) or (5), ２ and X ３ are each independently an alkylene group which may be interrupted by —S—, an alkylene group which may be interrupted by —NH—, or an alkylene group which may be interrupted by a linear or cyclic siloxane chain; R ２ are each independently a hydrolyzable group or a hydrocarbon group, provided that at least one R ２ is a hydrolyzable group, R ３ are each independently a hydrocarbon group; １ is 0 or a number from 1 to 1,000. [In the formula, A ４ is a group represented by formula (4) or (5), ４ and X ５ are each independently an alkylene group which may be interrupted by —S—, an alkylene group which may be interrupted by —NH—, or an alkylene group which may be interrupted by a linear siloxane chain; R ４ are each independently a hydrocarbon group, R ５ are each independently a hydrolyzable group or a hydrocarbon group, provided that at least one R ５ is a hydrolyzable group, a is an integer of 1 or more, and when a is an integer of 2 or more, each A ４ , X ４ and R ４ are the same or different, b is 0 or an integer of 1 or more, and when b is an integer of 2 or more, each X ５ , R ４ and R ５ are the same or different, c is 0 or an integer of 1 or more, and when c is an integer of 2 or more, each R ４ are the same or different, and a + b + c is an integer of 3 or more. The curable polyorganosiloxane composition according to claim 1, 4. The curable polyorganosiloxane composition according to claim 1, further comprising one or more members selected from the group consisting of (D) a crosslinking agent, (E) an adhesion promoter, and (F) a polyorganosiloxane having no silicon-bonded hydrolyzable groups.

5. A coating agent for electronic parts, which uses the curable polyorganosiloxane composition according to any one of claims 1 to 4.

6. A metal surface treatment agent using the curable polyorganosiloxane composition according to any one of claims 1 to 4.

7. A cured product obtained by curing the curable polyorganosiloxane composition according to any one of claims 1 to 4.

8. An electronic component comprising the curable polyorganosiloxane composition according to any one of claims 1 to 4.

9. (C) A compound containing a benzimidazolidinone moiety and a hydrolyzable group bonded to a silicon atom in one molecule.

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