JP2814179B2 - Antistatic curable composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antistatic curable composition capable of forming a cured product effective for antistatic and a cured product thereof.

[0002]

2. Description of the Related Art Curable organopolysiloxane compositions are used as sealing materials for coatings, coating materials, sealing materials for electric and electronic parts, bottling materials, surface treatment agents for fibers, automobiles, construction, electric and electronic parts. Widely used for applications such as adhesives, various plastic treatment agents, and various fiber treatment agents. An antistatic technique for such a curable organopolysiloxane composition is also known. For example, a method of adding a silicone oil having a hydrophilic group as a main component (Japanese Unexamined Patent Application Publication No.
52-103499), a method of adding a sulfonate (Japanese Patent Publication No. 3-59096), and a method of adding a fluorine-containing silicone oil (JP-A-1-83085, JP-A-1-83086)
JP-A Nos. 1-1121390), a method of adding a silicone oil containing a surfactant (Japanese Patent Application Laid-Open No. 1-294099), and a method of adding a conductive powder (Japanese Patent Application Laid-Open Nos. 2-69763 and 3). -292180, 4-86765) and the like have been proposed.

[0003]

However, the above-mentioned conventional antistatic technique is to form an antistatic cured product by adding a special additive or the like to the curable composition. Phase separation during storage of the composition,
When a problem such as precipitation occurs, or when cured, there is a problem that the additive bleeds on the surface of the cured product or that the surface of the cured product becomes sticky.

Accordingly, an object of the present invention is to provide a curable organopolysiloxane composition capable of forming a cured product having excellent antistatic properties without adding a special additive, and a cured product thereof. is there.

[0005]

According to the present invention, (A)
The following average composition formula (1): R ¹ _a X _b SiO _{(4-ab) / 2} (1) In the formula, R ¹ may be the same or different and is an unsubstituted or substituted monovalent hydrocarbon group; X may be the same or different, a hydroxyl group or a hydrolyzable group, a is a number of 1 to 3, and b is a number of 0.01 to 3, and 1.01 ≦ a + b <
An antistatic curable composition comprising 100 parts by weight of an organopolysiloxane represented by the following formula (4) and (B) 20 to 100 parts by weight of an organotitanium compound is provided.

Further, according to the present invention, there is provided a cured product obtained by curing the above curable composition, wherein the surface has a width of 0.1 to 100 μm and a height of 0 to 100 μm in a side cross section. .
A cured product having a large number of protrusions of 1 to 100 μm is provided.

[0007]

The curable composition of the present invention is a composition wherein the organopolysiloxane of the component (A) is hydrolyzed and condensed in the presence of moisture to form a cured product, and the organotitanium compound of the component (B) is It acts as a curing catalyst. Conventionally, an organic titanium compound is known as a condensation curing catalyst for an organopolysiloxane having a hydrolyzable silyl group, but its addition amount is about 1 part by weight based on 100 parts by weight of the organopolysiloxane to be cured. Was. On the other hand, in the present invention, by using an extremely large amount of the organic titanium compound of 20 parts by weight or more, a cured product excellent in antistatic properties was successfully formed.

That is, in the curable composition of the present invention,
Due to the large amount of the organotitanium compound, curing causes uneven curing.As a result, a large number of protrusions with a width of 0.1 to 100 μm and a height of 0.1 to 100 μm are formed on the surface of the cured product. As a result, it is believed that the cured product has a rough surface as a whole and exhibits excellent antistatic properties. In the present specification, the width of the protrusion is the distance between the roots a and b of the protrusion (an inflection point serving as a connection portion with an adjacent protrusion) in FIG. Means the maximum length, and the height means the distance between a line connecting these and the vertex c. Such projections can be sufficiently recognized with an electron microscope at a magnification of about 50 to 1000 times, and the distance can be measured from the photograph. If the width and height are outside the above ranges, effective antistatic properties will not be exhibited.

(A) Organopolysiloxane The organopolysiloxane of the component (A) serving as the base component of the curable composition of the present invention is represented by the above average composition formula (1).

In the average compositional formula (1), the monovalent hydrocarbon group R ¹ is an alkyl group such as a methyl group, an ethyl group or a propyl group; a cycloalkyl group such as a cyclohexyl group; a vinyl group or an allyl group. An alkenyl group; an aryl group such as a phenyl group; an aralkyl group such as a benzyl group or a phenylethyl group; a group in which some or all of the hydrogen atoms of these groups have been substituted with halogen atoms, for example, a chloromethyl group; A 3,3-trifluoropropyl group and the like can be exemplified.

The group X is a hydroxyl group or a hydrolyzable group, which includes a carboxyl group; an alkenyloxy group such as an isopropenoxy group and an isobutenyloxy group; a dimethylketoxime group and a methylethylketoxime. A ketoxime group such as a group; a methoxy group;
An alkoxy group such as an ethoxy group and a butoxy group; an acyloxy group such as an acetoxy group; an amino group such as an N-butylamino group, an N, N diacetylamino group and an n-butylamino group;
An aminoxy group such as an N, N-diethylaminoxy group;
An amide group such as a methylacetamide group can be exemplified.

Further, in the average composition formula (1), a is a number of 1 to 3, b is a number of 0.01 to 3, and 1.01 ≦ a + b
It is a number that satisfies <4. For example, if the value of b is smaller than this range, the curability will be unsatisfactory.

The molecular structure of the organopolysiloxane of the component (A) represented by the above average composition formula (1) is not particularly limited, and may be linear, branched, or cyclic. Generally, it is preferable that the resin is a resin at 25 ° C. The organopolysiloxane suitably used in the present invention is a block copolymer of a dimethylsiloxane unit and a phenylsiloxane unit, and is particularly a resin at 25 ° C. In this case, the molar ratio of the dimethylsiloxane unit (—SiMe ₂ —) and the phenylsiloxane unit (≡SiPh) [≡SiPh] / [−
SiMe ₂ −] is particularly preferably in the range of 1 to 5.

(B) Organotitanium Compound As the organotitanium compound of the component (B), a conventionally known organotitanium compound can be used. Specifically, tetraethoxytitanium, tetraisopropoxytitanium, tetran-butoxytitanium, tetrabis (2-ethylhexyloxy) titanium, tetrastearoxytitanium, diisopropoxybis (acetylacetona) titanium, di-n-butoxybis ( Triethanolaminato) titanium, tetraisopropoxytitanium polymer, alkoxytitanium such as tetra-n-butoxytitanium polymer, etc .; triacylate titanium such as tri-n-butoxytitanium stearate, isopropoxytitanium stearate, hydroxytitanium stearate; diiso Propoxy titanium bisacetylacetonate, dihydroxybislacto titanium, diisopropoxy titanium bis (acetylacetona), tris (acetylacetona)
A chelate type such as titanium; others, tetrabenzyl titanium, biscyclopentadienyl titanium dimethyl, biscyclopentadienyl titanium methyl, biscyclopentadienyl titanium, diphenyl titanium, dipyridium-titanium complex, tris- (2,2 ′ -Dipyridyl) titanium,
Biscyclopentadienyl dichloride, phenyl titanium dichloride, biscyclopentadienyl titanium chloride, isopropoxy-tri-N-ethylaminoethyl aminato titanium, tetraisopropoxybisdioctyl phosphite titanium, isopropoxy tridodecylbenzenesulfonyl titanium, iso Examples thereof include propoxytriisostearate titanium, titanium bisdioctylpyrophosphonyloxyacetate, bisdioctylphosphate ethylene glycolatophosphonyltitanium, and isopropoxytrisdioctylpyrophosphonyltitanium.

Further, a partial condensate, a partial acylate, a partial alcohol exchange, a partial ester exchange, a molecule or an intermolecular chelate of these organic titanium compounds,
A reaction product with an active hydrogen-containing compound such as an amine compound or a mercapto compound, a reaction product with an organic acid such as a sulfone-containing compound, or a reaction product with aluminum chloride.
A Ziegler catalyst, a reaction product with a carboxy compound such as terephthalic acid or an acid anhydride, a reaction product with a hydroxyl-containing or silanol-containing compound such as partially saponified polyvinyl alcohol or trimethylsilanol, and the like can also be used. Particularly preferably used in the present invention is alkoxytitanium.

These organic titanium compounds can be used alone or in combination of two or more. Further, the above-mentioned organic titanium compound is toluene, isopropanol,
Use of a solution of n-hexane, chlorobenzene, n-butanol, xylene or the like is not a problem.

As described above, the above-mentioned organotitanium compound is used in an amount of 20 to 100 parts by weight per 100 parts by weight of component (A).
Used in an amount of 0 parts by weight.

Other Ingredients The curable composition of the present invention may contain a cured product having excellent antistatic properties as long as the object of the present invention is not impaired.
In addition to the components (A) and (B) described above, various components can be added as needed. For example, storage stabilizers such as methyltrimethoxysilane, methyltripropenoxysilane, methyltributanoxime silane, vinyltributanoxime silane, methyltriacetoxysilane,
Reinforcing agents such as fumed silica, precipitated silica, aluminum oxide, quartz powder, carbon powder, talc and bentonite; fibrous fillers such as asbestos, glass fibers and organic fibers; coloring agents such as pigments and dyes; A heat resistance improver such as cerium, a cold resistance improver, a dehydrating agent, a rust preventive, an adhesion improver such as γ-glycidoxypropyltriethoxysilane, toluene, isopropanol, n-hexane, chlorobenzene, n-butanol,
Solvents such as xylene and the like, and for the purpose of accelerating the curing of component (A), tin naphthenate, tin caprylate, tin oleate, dibutyltin diacetate, dibutyltin dioctate, dibutyltin dilaurate, dibutyltindiolate,
Tin compounds such as diphenyltin diacetate, dibutyltin oxide, dibutyltin dimethoxide, dibutylbis (triethoxysiloxy) tin, dibutyltin benzylmalate, and amines such as octylamine and laurylamine;
Guanidyl group-containing silane compounds such as imidazoline, theolahydropyrimidine, 1,8-diazabicyclo (5,4,0) undecene-7 and guanidinepropyltris (trimethylsiloxy) silane which are cyclic amidines, and partial hydrolysates thereof; A basic compound such as a guanidyl group-containing siloxane can be appropriately blended.

Preparation of Composition The curable composition of the present invention is prepared as a one-pack type curable composition by uniformly mixing predetermined amounts of the above-mentioned components in a dry atmosphere. Further, it is also possible to use a two-pack type in which the components (A) and (B) are separately packaged in two liquids so as to be separated from each other, and mixed at the time of use. In the case of a two-pack type, it is easy to make the mixing ratio of the two packs 1: 1 and the workability is good.

Formation of Cured Product The above-mentioned curable composition is applied on a predetermined substrate and cured by exposure to the atmosphere to form a cured product. The application of the composition to the substrate surface can be performed by spray coating, brushing, dipping, or the like, but since it can be easily applied uniformly to the substrate surface or can be easily applied to a complex-shaped substrate surface, Spray application is preferred. Curing proceeds easily at room temperature, similarly to the usual condensation-curable organopolysiloxane composition, but may be heated if necessary. In this case, heating at a temperature of 250 ° C. or lower is preferable, and particularly, a range of 80 to 150 ° C. is particularly preferable from the viewpoint of workability.

In the present invention, the cured product formed as described above has a surface of 0.1 to 1 as described above.
Protrusions having a width of 00 μm and a height of 0.1 to 100 μm are formed, thereby exhibiting an excellent antistatic effect. The shape of such a projection may be narrower, intact, or thicker as it goes from the bottom to the top, but is not particularly limited as long as it has the above-described width and height, but goes to the top. Therefore, it is preferable to have a narrow shape, and it is preferable to have a rounded shape as a whole, and it is particularly preferable to be hemispherical. It is preferable that the projections occupy 10% or more of the surface of the cured product in order to exhibit an effective antistatic property.

The above-mentioned projections are believed to be formed by uneven curing of the curable composition. The shape and the proportion of the projections are appropriately used depending on the types of the components (A) and (B) used. It can be adjusted by controlling the rate of hydrolysis by adjusting the type and amount of the solvent used, the curing temperature, and the like. For example, in order to form a target projection by uneven curing, it is preferable that the component (A) and the component (B) are selected to have different numbers of functional groups or different combinations of hydrolyzable groups. The solvent is preferably capable of uniformly dissolving the components (A) and (B), and in particular, aromatic solvents such as toluene, benzene, and xylene are used alone or in combination of two or more.
Although the curing temperature is sufficient at room temperature, if necessary,
Curing can be carried out by heating to a temperature in the range up to, in particular, 120 to 150 ° C.

[0023]

In the following examples, Me represents a methyl group.

[0024] Examples 1-4, Comparative Examples _{1,2 Cl- (SiMe 2 O) 34} -SiMe 2 -Cl 100
By weight of phenyltrichlorosilane and 15 parts by weight of phenylmethyldichlorosilane in a toluene solution was blocked with tetramethoxysilane.
A toluene solution containing 50% by weight of the terminal-blocked organopolysiloxane was used as a sample (a). A sample (b) was prepared in the same manner as described above except that an organopolysiloxane whose terminal was blocked with methyltributanoximesilane was used instead of tetramethoxysilane.

Next, Samples (a) and (b) were mixed with each component at the compounding ratio shown in Table 1 to prepare a curable composition. Put this curable composition in a 100 g glass bottle at room temperature.
The storage stability was evaluated by visually observing the degree of phase separation of the sample that had been left for a month. Also, 2 cc of the curable composition was added to 15
It was spray-coated on silicone rubber KE 951 (manufactured by Shin-Etsu Chemical Co., Ltd.) of 15 m square, and cured by leaving it in an atmosphere of 20 ° C. and 60% RH. Twenty-four hours later, the antistatic effect of the obtained cured product was evaluated by using a static onestar (manufactured by Shishido Shosha Co., Ltd.) based on the half-life of charging when a voltage of 10 KV was applied.
Further, the tackiness of the cured product was evaluated by finger touch. In addition, the state of the protrusions formed on the surface of the cured product is indicated by OPTIPHOT66D-X6D.
(Manufactured by Nikon Corporation). Table 1 shows the results.

[0026]

[Table 1]

In the above table, the width of the projection is 0.1 to 100.
も の for those in the μm range, × for those that are not, 、 for those with a projection height in the range of 0.1-100 μm, x for those that are not, and the shape of the projections becomes thinner toward the top ○ indicates what is, and × indicates what is not
When the product occupies 10% or more of the surface of the cured product, it is shown as ○, and when not, it is shown as x.

[0028]

According to the curable organopolysiloxane composition of the present invention, a cured product having excellent antistatic properties can be formed without adding a special antistatic agent or the like. Therefore, the preservability of the composition before curing is good, and problems such as the bleeding out of the additive on the surface of the cured product and the stickiness on the surface of the cured product are effectively avoided. This composition is used for building sealing materials, coating materials, sealing materials for electric and electronic parts, bottling materials, surface treatment agents for fibers, automotive, construction, adhesives for electric and electronic parts, various plastic processing agents, etc. Widely used for various applications requiring antistatic function.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a state of a projection formed on the surface of a cured product of the present invention.

Claims (5)

(57) [Claims] (A) The following average composition formula (1): R ¹ _a X _b SiO _{(4-ab) / 2} (1) In the formula, R ¹ may be the same or different, and A substituted or substituted monovalent hydrocarbon group, X may be the same or different, a hydroxyl group or a hydrolysable group, a is a number of 1 to 3, and b is a number of 0.01 to 3, and An antistatic curable composition comprising 100 parts by weight of an organopolysiloxane represented by the following formula: 1.01 ≦ a + b <4, and (B) 20 to 100 parts by weight of an organotitanium compound. Stuff. 2. The curable composition according to claim 1, wherein the organic titanium compound is an alkoxy titanium. 3. The composition according to claim 1, wherein said organopolysiloxane is a block copolymer of a dimethylsiloxane unit and a phenylsiloxane unit, the organopolysiloxane having a molecular chain terminal blocked with an alkoxy group. . 4. A cured product obtained by curing the composition according to claim 1, wherein the surface has a width of 0.1 to 100 μm and a height of 0.1 to 100 μm in a side cross section. ~ 100
A cured product having many μm protrusions. 5. The cured product according to claim 4, wherein said projection is hemispherical.