JP2002322418A - Water-repellent coated layer forming composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-repellent coated layer forming composition that gives a cured coat layer having both of excellent processability and water repellency without containing hydrophobic fine particles. SOLUTION: The water-repellent coated layer-forming composition of excellent processability and high water repellency is prepared by formulating 3-70 pts.wt. of an organopolysiloxane bearing silanol groups, 1-5C alkyl groups and having 5-1,000 polymerization degree to 100 pts.wt. of an organopolysiloxane of >=150 polymerization degree having 1-5C alkyl groups (may include alkoxy groups and silanol groups).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for forming a water-repellent film, and more particularly to a composition applied to a surface of a substrate to form an effective water-repellent film, and to a substrate on which a film is formed as described above. The present invention relates to a composition for forming a water-repellent film capable of exhibiting extremely excellent workability without causing problems such as cracks and wrinkles in the film even during processing, molding or deformation.

[0002]

2. Description of the Related Art Conventionally, compositions for forming a water-repellent coating are disclosed in, for example, JP-A-3-215570, JP-A-3-244996, JP-A-4-45181, and JP-A-7-118577. Etc.
A fine particle-containing composition comprising (a) hydrophobic fine particles and (b) a resin binder has been proposed.

[0003] Specifically, JP-A-3-215570 discloses that (a) the surface tension is 32 × 10 ^-5 N / cm (32
dyn / cm) or less, and (b) a resin having a water absorption of 0.5% or less (one kind selected from the group consisting of silicone resin, fluorine resin, acrylic resin, epoxy resin, polyimide resin, etc. And water-repellent paints comprising at least two types of (a) inorganic or organic powders having a porous shape and a particle size of 4 μm or less; (B) A water-repellent coating composition comprising a solution of a silicone-based resin compound or a solution of a fluorine-based resin compound has been disclosed. Japanese Patent Application Laid-Open No. 4-45181 discloses a silicone having (b) a ratio of an organic group (methyl group or phenyl group) to a silicon atom: R / Si of less than 1.7 with a three-dimensional crosslinked body as a constituent unit. A water-repellent coating composition comprising a solution containing a base resin and (a) inorganic fine particles having a surface subjected to a hydrophobic treatment has been disclosed. Further, JP-A-7-118577 discloses that (B) a hydrophobizing filler having a hydrophobizing treatment having a hydrophobizing agent having a hydrophobizing treatment rate (calculated as carbon weight) of 2.7% by weight or more;
Each of the compositions for forming a water-repellent and anti-fungal film characterized by containing 25 to 85% by weight of a binder has been proposed.

A water-repellent film formed by curing a water-repellent coating composition comprising (a) hydrophobic fine particles and (b) a resin binder disclosed in these publications is, for example, the film. Water droplets dropped on the surface tend to roll down, and have an excellent water-repellent effect on water droplets dropped on the surface of the coating due to some factors. This phenomenon of water repellency is due to the fact that air easily intervenes between the water-repellent film whose surface has become uneven due to the presence of hydrophobic fine particles and the dropped water droplets. It is believed that this is caused by a synergistic effect of the formation of a layer having a small thickness and the fact that the hydrophobic fine particles themselves are substances having a low surface tension.

However, in the case where such a composition comprising (a) hydrophobic fine particles and (b) a resin binder is used for a member that comes into contact with condensed water droplets such as a heat exchanger of an air conditioner. However, the number of condensed water droplets generated on the member surface due to condensation such as condensation is overwhelmingly greater than the number of water droplets dropped on the member surface due to some factors. Thus, capillary condensation is caused in the concave portions and the like, and it becomes difficult to behave like a water drop dropped due to some factor.

[0006] Furthermore, particularly in the case of fins and plates of a heat exchanger, a configuration in which a plurality of members are provided at minute intervals is employed. When a water-repellent film is formed, a sufficient water-repellent effect cannot be expected due to the above-mentioned cause (capillary condensation), and water droplets are sandwiched between extremely narrow gaps between members existing at minute intervals. To thereby form
The drop of water droplets is further impeded, and the water repellency is further reduced, which causes a reduction in the amount of air passing through the heat exchanger, which also lowers the air conditioning performance of the heat exchanger. Has been raised.

In the water-repellent coating composition comprising (a) hydrophobic fine particles and (b) a resin binder, a large amount of hydrophobic material is contained in the water-repellent coating composition in order to improve the water-repellent effect. In many cases, it is necessary to contain hydrophobic fine particles, and excessive blending of the hydrophobic fine particles causes a decrease in the strength of the water-repellent coating formed by curing, and as a result, a coating having low durability is obtained. There was also an inherent problem of causing it.

Therefore, in order to solve these various problems, one of the applicants of the present invention disclosed in Japanese Unexamined Patent Publication No.
No. 65553 and JP-A-2000-119642 disclose R ₂ SiO _2/2 containing no particulate filler.
A silicone resin consisting of units and RSiO _3/2 units, particular composed of a polydialkylsiloxane water-repellent film-forming composition or a silicone resin composed of RSiO _3/2 units, polyalkyl hydrogen siloxane having a specific structure And a composition for forming a water-repellent coating composed of the following. In the water-repellent coating formed by these compositions, the water droplets adhering to the surface tend to slide down rather than roll off, and the surface of the water-repellent coating is smooth due to the absence of fine particles. And
As a result, capillary condensation does not occur, and excellent water repellency against condensed water droplets can be exhibited. Therefore, a composition that does not include such a particulate filler can be suitably used when water repellency is required on the surface of a member that is adjacent to another member with a small space therebetween. Becomes

However, in applications such as heat exchanger members (for example, fins), the assembling process requires forming a water-repellent coating on the substrate and then deforming the substrate. Sometimes. However, a water-repellent coating obtained from a composition containing no hydrophobic fine particles lacks properties such as flexibility, flexibility, and stretchability. Where the water-based coating cannot follow the deformation of the substrate, causing cracks or wrinkles on the water-repellent coating, or causing problems such as peeling of the water-repellent coating from the substrate. Thus, in practical use, the problem to be solved is inherent.

[0010]

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a coating film formed by curing without containing hydrophobic fine particles. The object of the present invention is to provide a composition for forming a water-repellent film that exhibits both excellent processability and water repellency, and in particular, deforms the substrate after film formation, even after a severe environment of molding or processing, An object of the present invention is to provide a composition for forming a water-repellent film which does not cause problems such as cracks, cracks, wrinkles, and peeling in the film and realizes excellent workability and water repellency.

[0011]

The present inventors have made intensive studies to solve such a problem, and as a result, combined a specific organopolysiloxane with a specific organopolysiloxane having a silanol group, By blending at a specific ratio to form a film-forming composition, it has been found that a water-repellent property can be realized, and a film having unprecedentedly excellent workability can be formed. It is.

Accordingly, the present invention has been completed based on such findings, and the gist of the present invention is as follows.
(A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1) and (B) 3 of an organopolysiloxane having a silanol group represented by the following general formula (2): To 70 parts by weight of the composition for forming a water-repellent film.

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That is, in such a composition for forming a water-repellent film according to the present invention, a specific organopolysiloxane which is a silicone resin and a specific organopolysiloxane having a silanol group which is a silicone oil are used. By mixing at a predetermined ratio, the synergistic action of the organopolysiloxane and the organopolysiloxane having a silanol group,
This makes it possible to form a coating with excellent workability. In addition, since the formed film is smooth, the performance is not reduced by the condensed water droplets, and the water repellency (water-repellent performance) in which the water droplets slide down rather than roll. Is realized advantageously.

According to one preferred embodiment of the composition for forming a water-repellent film excellent in processability according to the present invention,
(C) It is desirable that the adhesion improver comprising a silane having an epoxy group or an acyloxy group is further contained in a proportion of 0.01 to 70 parts by weight, whereby the water-repellent coating is formed on the substrate. Since it is formed with excellent adhesion on the surface, problems such as peeling of the film can be advantageously solved.

According to another preferred embodiment of the composition for forming a water-repellent film according to the present invention, (D) a curing accelerator comprising a curing catalyst or an organic peroxide comprises 0.01 to 3%.
It is desirable that the water-repellent film be further contained in a proportion of 0 parts by weight, and by employing such a curing accelerator, the curing time for forming the water-repellent coating can be advantageously shortened.

Further, according to another desirable embodiment of the composition for forming a water-repellent film according to the present invention, the constitution in which a diluting solvent is added to form a liquid composition is advantageous for application to a substrate. , It is preferably adopted.

[0017]

The composition for forming a water-repellent film according to the present invention comprises (A) an organopolysiloxane represented by the aforementioned general formula (1) and (B)
And an organopolysiloxane having a silanol group represented by the general formula (2) represented by the general formula (4). The organopolysiloxane represented by the general formula (1) which is one of the essential components constituting the organopolysiloxane. Polysiloxane is a hydrolysis-condensation product and has a resin or a resin-like structure.

In the general formula (1), R ¹
And R ³ each independently represent an alkyl group having 1 to 5 carbon atoms. Examples of such an alkyl group having 1 to 5 carbon atoms include a methyl group, an ethyl group, and an n group.
-Propyl group, isopropyl group, n-butyl group, isobutyl group, and the like. Among them, a methyl group is particularly preferable. In addition, R ² in the general formula (1)
And R ⁴ each independently represent at least one substituent selected from a hydroxyl group and an alkoxy group having 1 to 5 carbon atoms. Here, the type of such an alkoxy group,
1 of the organopolysiloxane represented by the general formula (1)
The ratio of the hydroxyl group and the alkoxy group in the molecule is not particularly limited, but in the former alkoxy group, as the number of carbon atoms decreases, the reactivity becomes higher, and in the latter case, As the ratio of hydroxyl groups to alkoxy groups increases, the reactivity improves, but the storage stability of the composition for forming a water-repellent film decreases. Selection or adjustment is appropriately made according to the mode or the like.

In the organopolysiloxane represented by the general formula (1) employed in the present invention, the monofunctional unit [R ^a ₃ SiO
_1/2 ] (where ^Ra is an organic group), but tetrafunctional units [SiO _4/2 ] and the like may be produced as by-products and remain, but they may exert the characteristic effects of the present invention. Needless to say, as long as the unit is not given, there is no problem even if those units remain.

Furthermore, in such formula _{^{(1), [R 1 2}} R 2 m SiO (2-m) / 2] units and [R ³ R ⁴ _n S
i and (a) indicate the number of repetitions of the [O _{(3-n) / 2} ] unit, and 0.70 ≦ b / (a + b) ≦ 0.95, more preferably 0.80 ≦ b / (a + b). It is desirable that the numerical value satisfy the inequality ≦ 0.95. If the value of [b / (a + b)] is too small, the strength of the cured film obtained by such a composition for forming a water-repellent film decreases, while if it is too large, ,
This is because the processability of the cured film tends to decrease.

In addition, such a and b are [a +
b], in other words, the value indicating the size (degree of polymerization) of the organopolysiloxane represented by the general formula (1) is
It is desirable that the inequality satisfy 150 ≦ a + b, and more preferably, 300 ≦ a + b. If the organopolysiloxane represented by the general formula (1) satisfies the condition of 150 ≦ a + b, it may be used alone or after being diluted with an organic solvent, depending on its liquid or solid form. With the organopolysiloxane having a silanol group represented by the general formula (2), the composition according to the present invention can be constituted. Note that this [a
When the value of [+ b] is less than 150, sufficient workability cannot be imparted to the formed water-repellent coating. The upper limit of the value of [a + b] is not particularly limited. However, as will be described in detail later, a configuration in which the organopolysiloxane is diluted with an organic solvent in order to advantageously apply the composition to a substrate. Is required to be soluble in the organic solvent used. For example, it is desirable that the solvent be soluble in benzene or the like.
000 is desirable. However, the organopolysiloxane represented by the general formula (1) has various sizes (degrees of polymerization) by adjusting the polymerization reaction during the production.
Is obtained, and by completing the polymerization reaction, an insoluble / infusible substance having a remarkably large degree of polymerization may be produced.However, such an insoluble / infusible substance is not practical. Of course, what is undesirable is, needless to say.

Further, in the general formula (1), m and n
Are 0 ≦ m ≦ 0.33 and 0 <n ≦ 1.
It is preferable that the condition of 00 (inequality) be satisfied, and that the range of 0 ≦ m ≦ 0.1 and 0 <n ≦ 0.2 be satisfied. However, when the value of m or n is excessively large, the workability of the obtained cured film is reduced,
The decrease in water repellency due to the remaining hydrophilic functional groups is caused, and the desired water repellent coating cannot be formed.

When producing the organopolysiloxane represented by the general formula (1) as described above,
Conventionally known production methods can be adopted.For example, organotrialkoxysilanes and diorganodialkoxysilanes can be prepared using an acidic catalyst such as hydrochloric acid, or a basic catalyst such as potassium silanolate and water, and alcohol and To produce the desired organopolysiloxane by using a method of polymerizing in an aromatic solvent or a method of polymerizing organotrihalosilane and diorganodialkoxysilane in water, an alcohol and an aromatic solvent. However, the present invention is not limited to these methods.

A specific example of the organopolysiloxane represented by the general formula (1) suitably used in the present invention is, for example, the one represented by the following chemical formula (5).

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On the other hand, in the composition for forming a water-repellent film according to the present invention, the organopolysiloxane having a silanol group represented by the general formula (2), which is another essential component constituting the composition, is an oil or an oily oil. belongs to.

Here, R ⁵ , R ⁶ , R ⁸ , R ⁹ , R ¹⁰ and R ¹¹ in the general formula (2) each independently represent an alkyl group having 1 to 5 carbon atoms. So,
And, as such an alkyl group, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group and the like can be exemplified, and among them, a methyl group is particularly preferable. On the other hand, R ⁷ and R
¹² represents a hydroxyl group or an alkyl group having 1 to 5 carbon atoms. However, at least one of R ⁷ and R ¹² is particularly required to be a hydroxyl group. When R ⁷ or R ¹² is an alkyl group, examples of such an alkyl group include a methyl group, an ethyl group, an n-propyl group,
An isopropyl group, an n-butyl group, an isobutyl group and the like are used, and among them, a methyl group is particularly preferable.

In the general formula (2), x and y are respectively 0 ≦ x, 0 <y, 5 ≦ x + y ≦ 10
It is a number that satisfies the inequality of 00, and in such a range, it is particularly preferable that 10 ≦ x + y ≦ 300. Moreover, such x and y are 0.8 ≦ y / (x +
y) satisfies the inequality of ≦ 1.0, and among them,
It is desirable that the number satisfies 0.9 ≦ y / (x + y) ≦ 1.0. Here, [x +
When the value of [y] is too small, good water repellency cannot be imparted to the cured film obtained from such a composition, while when the value of [x + y] is too large, it is obtained. There is a problem that sufficient strength cannot be given to the cured film. On the other hand, if the value of [y / (x + y)] is too small, the remaining hydroxyl groups increase, and the water repellency of the cured film formed from the composition is reduced. The organopolysiloxane having a silanol group represented by the general formula (2) is a conventionally known substance, and can be synthesized by a conventionally known production method. Examples of the method include hydrolysis and condensation of halosilane, but the method is not limited thereto.

Some specific examples of the organopolysiloxane having a silanol group suitably used in the present invention are shown in the following chemical formulas (6) to (9). It is needless to say that the thing is not to be interpreted in a limited manner.

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In preparing the composition for forming a water-repellent film according to the present invention, the above-mentioned (A) an organopolysiloxane represented by the general formula (1) and (B)
The silanol group-containing organopolysiloxane represented by the general formula (2) is to be compounded at a predetermined ratio. In the present invention, such a compounding ratio is represented by the general formula (1) With respect to 100 parts by weight of the organopolysiloxane represented by the general formula (2)
It is necessary to employ a compounding ratio which allows addition of 3 to 70 parts by weight of the organopolysiloxane having a silanol group represented by the formula. That is, a film capable of realizing the property can be formed. In particular, the mixing ratio of the organopolysiloxane having a silanol group represented by the general formula (2) is more preferably
1 of the organopolysiloxane represented by the general formula (1)
3 to 50 parts by weight is recommended for 00 parts by weight. When the content of the organopolysiloxane having a silanol group represented by the general formula (2) is too small, the water repellency of the formed cured film becomes insufficient, while the content is too large. If so, the mechanical properties of the formed film will be reduced.

The composition for forming a water-repellent film of the present invention may further comprise a silane having an epoxy group as an adhesion improver, if necessary, in order to improve the adhesion between the substrate and the water-repellent film. Alternatively, a silane having an acyloxy (acyloxy) group can be added. Incidentally, the addition ratio of the adhesion improver is 0.1 to 100 parts by weight of the organopolysiloxane represented by the general formula (1).
01 to 70 parts by weight, more preferably 0.01 to 40 parts by weight can be advantageously employed. However, if the proportion of such addition is excessive, not only the effect of improving the adhesiveness corresponding to the addition is not obtained, but also problems such as a decrease in the adhesiveness and a decrease in the strength of the cured film are caused. It is.

As the silane having an epoxy group, which is an example of such an adhesion improver, any conventionally known silane having an epoxy group may be appropriately employed as long as it has the effects described above. Is done, for example,
Glycidoxypropyltrimethoxysilane, glycidoxypropylmethyldimethoxysilane, glycidoxypropyltriethoxysilane, glycidoxypropylmethyldiethoxysilane, glycidoxyhexyltrimethoxysilane, glycidoxyhexyltriethoxysilane, epoxy Examples thereof include, but are not limited to, propyltrimethoxysilane, epoxypropyltriethoxysilane, epoxyhexyltrimethoxysilane, and epoxyhexyltriethoxysilane.

On the other hand, the silane having an acyloxy group, which is another example of the adhesion improver, has an effect of improving the adhesion between the substrate and the cured film, similarly to the silane having the epoxy group. If so, conventionally known silanes having various acyloxy groups can be appropriately employed. For example, specific examples of the silane having such an acyloxy group include acryloxypropyltrimethoxysilane, acryloxypropylmethyldimethoxysilane, acryloxypropyltriethoxysilane, acryloxypropylmethyldiethoxysilane, and acryloxyhexyltrimethoxysilane. Silane, acryloxyhexyltriethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxypropylmethyldimethoxysilane, methacryloxypropyltriethoxysilane, methacryloxypropylmethyldiethoxysilane, methacryloxyhexyltrimethoxysilane, methacryloxyhexyltriethoxy Although silane and the like can be mentioned, it is needless to say that the invention is not limited to these.

When adding a silane having an epoxy group or a silane having an acyloxy group as an adhesion improver as described above, the effect is exhibited if any of these compounds is used. Two or more silanes having an epoxy group may be used in combination.
This is the same in the case of a silane having an acyloxy group. Furthermore, one or more silanes having an epoxy group and one or more silanes having an acyloxy group can be used in combination.

The composition for forming a water-repellent film according to the present invention forms a water-repellent film by being applied to the surface of a substrate or the like and cured. The curing of such a composition can be performed at room temperature, but can be naturally performed by performing a heat treatment to shorten the curing time. In particular, in order to further accelerate the curing of such a film-forming composition or to shorten the curing time, if necessary, a curing catalyst or an organic peroxide may be further used as a curing accelerator to form a water-repellent film. It can be added to the composition. The ratio of the addition of the curing accelerator varies depending on the type of the curing catalyst and the type of the organic peroxide to be used, but generally, 100 parts by weight of the organopolysiloxane represented by the general formula (1). On the other hand, 0.01 ~
It is desirable that the amount be 30 parts by weight, more preferably 0.01 to 20 parts by weight. However, if the addition ratio of such a curing accelerator is excessive, gelation or thickening of the composition for forming a water-repellent film of the present invention is caused, and it becomes difficult to apply the composition to a substrate. Or the hydrophilic component contained in the curing catalyst or the organic peroxide, or the hydrophilic component generated by the decomposition or reaction of the curing catalyst or the organic peroxide deteriorates the water repellency of the formed film. This is because a problem such as doing so is caused.

The curing catalyst as the curing accelerator is not particularly limited as long as it promotes the curing of the composition for forming a water-repellent film according to the present invention. The curing catalyst can be appropriately used. For example, representatively, an organic metal compound and an amino group-containing compound are typically mentioned, and some of the more detailed specific examples will be listed below, but it is not limited to only those examples. Needless to say. The former organometallic compounds include organic tin compounds, organic titanium compounds, organic lead compounds, organic zinc compounds, organic iron compounds, organic zirconium compounds, organic cobalt compounds, and the like. Compounds (for example, chelate titanium, chelate zirconium, chelate cobalt, etc.) will also be included.

-Organometallic compounds-Organotin compounds Tin diacetate, tin dioctylate, tin dilaurate, tin tetraacetate, dibutyl tin diacetate, dibutyl tin dioctylate, dibutyl tin dilaurate, dibutyl tin dioleate, dimethoxy dibutyl Tin, dibutyltin oxide, dibutyltin benzylmaleate, dibutyltin bis (triethoxysiloxy) dibutyltin, diphenyltin diacetate ・ Organic titanium compounds tetramethoxytitanium, tetraethoxytitanium, tetra-n-propoxytitanium, tetra-i-propoxytitanium , Tetra-n-butoxytitanium, tetra-i-butoxytitanium, tetrakis (2-ethylhexoxy) titanium, di-i-propoxybis (ethylacetoacetate) titanium, dipropoxybis (acetylacetonato) titanium, di-i- Propoxybis (Acetylacetonate) titanium, dibutoxybis (acetylacetonate) titanium, tri-i-propoxyallyl acetate titanium, titanium isopropoxyoctylene glycol, bis (acetylacetonato) titanium oxide ・ organic lead compound lead diacetate, bis (2 -Ethylhexanoic acid) lead, dineodecanoate, lead tetraacetate, tetrakis (n-propionic acid)
Lead ・ Organic zinc compound Zinc diacetate, zinc bis (2-ethylhexanoate), zinc dinedecanoate, zinc diundecenoate, zinc dimethacrylate ・ Organic iron compound Iron diacetate ・ Organic zirconium compound Tetrakis (2-ethylhexanoic acid) Zirconium, zirconium tetrakis (methacrylic acid) ・ Organic cobalt compound Cobalt diacetate

-Amino Group-Containing Compound- Aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, tetramethylguanidine, tetramethylguanidylpropyltrimethoxysilane, tetramethylguanidine Zirpropylmethyldimethoxysilane, tetramethylguanidylpropyltris (trimethylsiloxy) silane, 1,8-
Diazabicyclo [5.4.0. -7-undecene, di-n-hexylamine, triethanolamine, dicyclohexylamine, di-n-octylamine, triethylamine, diethylamine, triethylbenzylamine, ethylenediamine, diethylenetriamine, triethylenetetraamine

On the other hand, the organic peroxide as the curing accelerator is not particularly limited as long as it has an effect of promoting curing, and various kinds of conventionally known organic peroxides may be appropriately used. Can be adopted. Specific examples of organic peroxides include ketone peroxides, peroxyketals, hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxydicarbonates, peroxyesters, and peroxides not classified into these, Specific examples of these are shown below, but are not limited thereto.

Ketone peroxide dimethyl ethyl ketone peroxide, dicyclohexanone peroxide, dimethylcyclohexanone peroxide, methyl acetoacetate peroxide, acetylacetone peroxide peroxyketal 1,1-bis (t-butylperoxy) cyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) cyclododecane hydroperoxide p-menthanehydroperoxide, diisopropylbenzene hydroperoxide, cumin hydroperoxide, t -Hexyl hydroperoxide ・ Dialkyl peroxide Dicumyl peroxide, t-butylcumyl peroxide, di-t-butyl peroxide Diacyl peroxide dioctanoyl peroxide, m-toluoylbenzoyl peroxide, dibenzoyl peroxide, di-m-toluoyl peroxide peroxydicarbonate diisopropylperoxydicarbonate, di-n-butylperoxydicarbonate・ Peroxyester cumylperoxyneododecanoate, t-butylperoxyneododecanoate, t-butylperoxyisobutyrate, t-hexylperoxyisopropyl monocarbonate, t-butylperoxyisopropyl monocarbonate, t -Hexyl peroxybenzoate,
t-butyl peroxybenzoate, t-butyl peroxy acetate • Other peroxides t-butyl trimethylsilyl peroxide

When such a curing accelerator is used, a curing catalyst and an organic peroxide can be used in combination, but when the curing catalyst serves as a reaction accelerator for the organic peroxide. From a certain point, it is desirable to use each separately.

In the composition for forming a water-repellent film according to the present invention, a composition in which a diluting solvent is added, if necessary, to form a liquid composition is advantageously employed. Becomes By using such a liquid composition, application to the surface of a substrate to which water repellency is to be imparted can be extremely advantageously performed.

Examples of such a diluting solvent (organic solvent) include aromatic hydrocarbon compounds such as benzene, toluene and xylene, ether compounds such as diethyl ether, diisopropyl ether and tetrahydrofuran, methanol, ethanol, propanol, butanol, and the like. Alcohol compounds such as hexanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, ketone compounds such as cyclohexanone, ester compounds such as ethyl acetate and butyl acetate, chloroform, trichloroethylene, halogenated hydrocarbon compounds such as carbon tetrachloride, n-hexane, n −
Saturated hydrocarbon compounds such as octane, isooctane, and cyclohexane; silane compounds such as trimethylmethoxysilane, dimethyldimethoxysilane, methyltrimethoxysilane, and tetraethoxysilane; hexamethyldisiloxane; tetracyclo-1,2-dimethylsiloxane; And at least one of these is appropriately selected and used, but is not limited thereto.

The ratio of the diluting solvent used is not particularly limited, but the organopolysiloxane represented by the general formula (1) and the organopolysiloxane represented by the general formula (2) used in the present invention are used. The total amount is preferably in the range of 0 to 10,000 parts by weight, and more preferably 10 to 2,000 parts by weight, based on 100 parts by weight of the total amount of the organopolysiloxane having a silanol group. Preferably, by adopting such a ratio, a liquid composition having such a viscosity that application to a substrate is further facilitated is obtained.

Further, the composition for forming a water-repellent film of the present invention as described above may contain, if necessary, a pigment, a dye, an ultraviolet coloring dye, a leveling agent, a fungicide, a preservative, an antioxidant, and an anticorrosion. Agents, rust inhibitors, antistatic agents, flame retardants, antifouling agents, etc.
Various conventionally known additives to be added to the film-forming composition can be appropriately selected and added in an appropriate amount as long as the water repellency and workability of the obtained cured film are not impaired.

Means for applying the composition for forming a water-repellent film of the present invention obtained by blending the above-mentioned components to a substrate include roll coating, dip coating, impregnation, flow coating, and brush. Various known methods such as a coating method and a spray method can be exemplified. By appropriately selecting and carrying out such a method, the composition for forming a water-repellent film according to the present invention can be used as a base. This makes it possible to apply smoothly on the surface of the material. The thickness of the cured film formed on the surface of the base material is not particularly limited, but is preferably, for example, 0.1 to 50 μm so that both workability and water repellency can be maximized. It is formed to have a film thickness.

The curing time for forming such a cured film depends on the components contained in the composition for forming a water-repellent film, but when the above-mentioned curing accelerator is not added, Is generally room temperature: 2 days, 50
Curing can be performed in 2 hours at 250 ° C., within 1 minute at 250 ° C., and several seconds at 350 ° C. If the temperature at the time of curing is too low, the reaction does not proceed sufficiently. Conversely, if the temperature is too high, siloxane which is an essential component of the present invention may be decomposed.

On the other hand, when a curing accelerator such as a curing catalyst or an organic peroxide is added, excellent curing time can be shortened as compared with the case where no curing accelerator is used. Curability can be realized. Further, it is desirable to adopt a normal temperature to 350 ° C. as the curing temperature, and among them, practically, particularly, 50 ° C. to 3 ° C.
Desirably, the temperature range is 00 ° C.

The substrate to which the composition for forming a water-repellent film according to the present invention is applied is not particularly limited, and various materials such as metals, glass, plastics, inorganic materials, rubber, fibers and the like can be used. It is possible to advantageously employ a substrate made of.

The composition for forming a water-repellent film of the present invention is basically a product, a material, a part or the like which requires water repellency, for example, a heat exchanger, a glass for an automobile, a glass for a building, a kitchen, or the like. The present invention can be advantageously applied to various members that can be used in a place that is easily wetted by water, such as a lavatory or a bathroom, or a place with high humidity. In particular, in the cured film formed by the water-repellent film-forming composition according to the present invention, the properties such as excellent flexibility and flexibility, stretchability and the like can be effectively exhibited. After forming the water-repellent film on the base material, the present invention can be applied to various members manufactured through a severe environment in which deformation, molding, processing, or the like is performed.

[0050]

EXAMPLES Hereinafter, some examples of the present invention will be described to clarify the present invention more specifically. However, the present invention imposes some restrictions by the description of such examples. It goes without saying that you don't receive anything. In addition, in addition to the following examples, the present invention may further include various changes and modifications based on the knowledge of those skilled in the art without departing from the spirit of the present invention. , Improvements and the like can be added.

-Organopolysiloxane- An organopolysiloxane (hereinafter abbreviated as A component) having a structure shown in Table 1 below was prepared. In Table 1, [a + b] indicates gel permeation chromatography (GPC) [HLC-80
20 (manufactured by Tosoh Corporation), column: TSKgelGM
HXL-L, G1000HXL (Tosoh Corporation),
Solvent: toluene], and calculated from the measured value of the weight average molecular weight (Mw) in terms of standard polystyrene, and [b / (a +
b)] and m and n are the ²⁹ Si NMR spectra [AC
P-300 (manufactured by Bruker, Germany)].

[0052]

[Table 1]

-Organopolysiloxane having a silanol group-Organopolysiloxane having a silanol group (hereinafter referred to as "organopolysiloxane")
As the component (B), one having a structure shown in Table 2 below was prepared. In Table 2,
The values of [x + y] and [y / (x + y)] are ²⁹ Si
It was determined from the measured value of NMR spectrum [ACP-300 (manufactured by Bruker, Germany)].

[0054]

[Table 2]

-Silane having an epoxy group or an acyloxy group- As an adhesion improver (hereinafter abbreviated as "C component"), silanes having an epoxy group or silanes having an acyloxy group shown in Table 3 below were prepared.

[0056]

[Table 3]

-Curing Catalyst or Organic Peroxide- As a curing accelerator (hereinafter abbreviated as D component), a curing catalyst or an organic peroxide shown in Table 4 below was prepared.

[0058]

[Table 4]

Next, the component B shown in Table 2 and the component C shown in Table 3 were further added to 100 parts by weight of the component A shown in Table 1 above, and further, D shown in Table 4 above. The components were added so that the mixing ratio [parts by weight] shown in Tables 5 and 6 below was added, followed by mixing and stirring. At this time, xylene is added as a diluting solvent, and the mixture is stirred, so that the final active ingredient concentration becomes 3%.
The liquid water-repellent film forming compositions according to Examples 1 to 22 and Comparative Examples 1 to 15 were adjusted to be 0% by weight.

[0060]

[Table 5]

[0061]

[Table 6]

Next, using the compositions for forming water-repellent coatings of Examples 1 to 22 and Comparative Examples 1 to 15 prepared as described above, coatings were formed in the following manner. That is, an aluminum plate (JIS-A1050P) on which a liquid water-repellent film forming composition was previously subjected to alkali degreasing treatment (FC-315: manufactured by Nippon Parkerizing Co., Ltd.) using a bar coater (No. 4). Then, by heating in an oven, a cured film having a thickness of 0.5 to 2.0 μm was formed on the surface of the substrate. As the curing conditions, in the case of a composition containing the D component, a heating temperature in an oven of 250 ° C. for 15 seconds is employed, while a composition containing no curing accelerator is used. In case, 250 ℃ ×
60 seconds were employed.

Examples 1 to 22 and Comparative Examples 1 to 1
For each of the cured films formed using the water-repellent film-forming composition of No. 5, the evaluation of water repellency and the appearance, strength, and workability of the cured film were performed by the following methods.

-Evaluation of Water Repellency- The evaluation of water repellency was performed by measuring the falling time of water drops. That is, the substrate on which the cured film is formed is placed on a horizontal support, and at a predetermined position on the surface of the film,
3.0 μL with a micropipette or microsyringe
Of distilled water was dropped, and the water droplet was allowed to stand. Then, before 30 seconds elapse after the drop of water drops, while the one side of the substrate is in contact with the horizontal support, the other side is lifted and the substrate is made to stand up, and in this state, a distance of 100 mm is dropped. The time required to perform was measured. The same operation was performed five times at different locations on the substrate surface, and the average value was determined as the time for dropping water droplets. The results are shown in Tables 7 and 8 below. When the water drop time is 60 seconds or less, excellent water repellency is recognized.
While a mark was given, the others were marked with x (fail). The measurement was performed for a maximum of 10 minutes.
If it has not reached 100 mm even after 0 minutes,
Not dropped.

-Evaluation of Appearance of Coated Film- The appearance of the cured film was evaluated by observing the surface state of the cured film formed on an aluminum plate at a magnification of 5 times with a stereo microscope (SZH: manufactured by Olympus Optical Industries, Ltd., objective Lens: DF Plan 0.5 ×, eyepiece: GWH1
0-D and GWH10-CD), and the following four-stage judgment is performed according to the state of the film defect (such as yuzu, irregularities, spots, grooves, and cracks) and the state of smoothness. The results were shown in Tables 7 and 8 below, with the results as pass (O) and the other cases as fail (X). <Judgment criteria> No film defects are found on the film surface. 2. Slight skin, unevenness, spots, etc. are observed on the surface of the coating. 3. Yuzu skin, irregularities, spots, etc. are observed on the surface of the coating. 4. The surface of the coating has a remarkable decrease in smoothness due to, for example, yuzu, irregularities, and spots.

-Evaluation of coating strength- The strength of the cured coating was evaluated by forming it into an aluminum plate.
Using the cured coating that was
A rejection was judged. First, a cured film is formed
Aluminum plate with friction coefficient measuring device (HEIDON
-14DR: Shinto Kagaku Co., Ltd.)
Non-woven gauze (Ben Lize: made by Asahi Kasei Kogyo Co., Ltd.)
Steel flat plate jig covered with 8 layers (9 square
00mm ^Two) And put a 1kg load on it.
In this state, move the flat jig horizontally to
A reciprocating motion was performed 20 times at a distance of 00 mm. Hardness at this time
Degradation of the passivated film was examined by a stereoscopic microscope (SZ) at 20x magnification.
H: Olympus Optical Co., Ltd., objective lens objective lens
: D. F. Plan2x, eyepiece: GWH10
-D and GWH10-CD), scratches, cracks, peeling
According to the state of the film defect such as the above, four-stage judgment is performed, and 1
Or, pass 2 if it is acceptable (○), otherwise it is not acceptable
The results are shown in Tables 7 and 8 below as the case (x).
did. <Judgment criteria> No deterioration of the coating surface is observed. 2. Slight scratches are observed on the coating surface. 3. Scratches and peeling are observed on the coating surface. 4. The coating surface is almost peeled off.

-Evaluation of processability- The processability (film flexibility) of the cured film was evaluated by the following method using the cured film formed on the aluminum plate, and passed or failed was judged. . That is, the aluminum plate on which the cured film is formed is subjected to a bending test (J
IS K 5400) into a bending tester,
Without a mandrel, it was folded outward in two. The state of the cured film in the bent portion was examined at a magnification of 20 times with a stereoscopic microscope (SZH: manufactured by Olympus Optical Industrial Co., Ltd., objective lens objective lens: DF Plan2 ×, eyepiece lenses: GWH10-D and GWH10-CD). Observe with
According to the state of film defects such as scratches, cracks, peeling, etc., a four-stage judgment was made, and the case of 1 or 2 was judged as pass (○), the other cases were judged as unacceptable (×), and the results were shown in Table 7 below. And Table 8 together. <Judgment criteria> No change on the coating surface is observed. 2. Slight cracks are observed on the coating surface. 3. Cracks and peeling are observed on the coating surface. 4. The coating surface is almost peeled off.

Further, as the pass / fail judgment of the comprehensive evaluation, if all the above evaluations are pass (o), pass (o) is judged; otherwise, the judgment of reject (x) is made. The results are shown in Tables 7 and 8 below.

[0069]

[Table 7]

[0070]

[Table 8]

As is evident from Table 7, the coating formed by using the composition for forming a water-repellent coating according to the present invention achieves excellent water repellency and strength, and at the same time, extremely excellent processing. It can be seen that the property is also given.

Hereinafter, some preferred embodiments of the present invention will be described. It goes without saying that the present invention is not limited to the embodiments described in detail below.

<Embodiment 1> (A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1-1) and (B)
A composition for forming a water-repellent film, comprising 3 to 70 parts by weight of an organopolysiloxane having a silanol group represented by the general formula (2-1):

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<Embodiment 2> (A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1-1) and (B)
2 to 3 to 70 parts by weight of the organopolysiloxane having a silanol group represented by the general formula (2-1), and
(C) 0.01 to 70 of a silane having a glycidoxy group
A composition for forming a water-repellent film, comprising:

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<Embodiment 3> (A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1-1) and (B)
3 to 70 parts by weight of the organopolysiloxane having a silanol group represented by the general formula (2-1)
(C) A composition for forming a water-repellent film, comprising 0.01 to 70 parts by weight of a silane having an acryloxy group or a methacryloxy group.

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<Embodiment 4> (A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1-1) and (B)
6 to 3 to 70 parts by weight of an organopolysiloxane having a silanol group represented by the general formula (2-1);
(D) A composition for forming a water-repellent film, comprising 0.01 to 20 parts by weight of a curing accelerator.

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<Embodiment 5> (A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1-1) and (B)
8 to 3 to 70 parts by weight of an organopolysiloxane having a silanol group represented by the general formula (2-1);
A composition for forming a water-repellent film, comprising 0.01 to 70 parts by weight of a silane having a glycidoxy group and (D) 0.01 to 20 parts by weight of a curing catalyst.

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<Embodiment 6> (A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1-1) and (B)
0 to 3 to 70 parts by weight of an organopolysiloxane having a silanol group represented by the general formula (2-1);
A composition for forming a water-repellent film, comprising: 0.01 to 70 parts by weight of a silane having a glycidoxy group; and 0.01 to 20 parts by weight of (D) an organic peroxide.

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<Embodiment 7> (A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1-1) and (B)
2. A composition for forming a water-repellent film, comprising 3 to 70 parts by weight of an organopolysiloxane having a silanol group represented by the general formula (2-2).

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<Embodiment 8> (A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1-1) and (B)
4 to 3 to 70 parts by weight of an organopolysiloxane having a silanol group represented by the general formula (2-2),
(C) 0.01 to 70 of a silane having a glycidoxy group
A composition for forming a water-repellent film, comprising:

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<Embodiment 9> (A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1-1) and (B)
6, 3 to 70 parts by weight of the organopolysiloxane having a silanol group represented by the general formula (2-2), and
(C) A composition for forming a water-repellent film, comprising 0.01 to 70 parts by weight of a silane having an acryloxy group or a methacryloxy group.

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<Embodiment 10> (A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1-1) and (B)
8 to 3 to 70 parts by weight of an organopolysiloxane having a silanol group represented by the general formula (2-2);
A composition for forming a water-repellent film, comprising 0.01 to 70 parts by weight of a silane having a glycidoxy group and (D) 0.01 to 20 parts by weight of a curing catalyst.

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<Embodiment 11> (A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1-1) and (B)
0 to 3 to 70 parts by weight of an organopolysiloxane having a silanol group represented by the general formula (2-2);
A composition for forming a water-repellent film, comprising: 0.01 to 70 parts by weight of a silane having a glycidoxy group; and 0.01 to 20 parts by weight of (D) an organic peroxide.

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<Embodiment 12> (A) 100 parts by weight of a benzene-soluble organopolysiloxane represented by the following general formula (1):
(B) A composition for forming a water-repellent film, comprising 3 to 70 parts by weight of an organopolysiloxane having a silanol group represented by the following general formula (2):

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<Embodiment 13> The repellent according to embodiment 12, further comprising (C) an adhesion improver comprising a silane having an epoxy group or an acyloxy group in a proportion of 0.01 to 70 parts by weight. A composition for forming an aqueous film.

<Embodiment 14> The water-repellent coating according to embodiment 12, further comprising (D) a curing accelerator comprising a curing catalyst or an organic peroxide in a proportion of 0.01 to 30 parts by weight. Forming composition.

<Embodiment 15> The water-repellent coating according to embodiment 13, further comprising (D) a curing accelerator comprising a curing catalyst or an organic peroxide in a proportion of 0.01 to 30 parts by weight. Forming composition.

<Embodiment 16> (A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1-2) and (B)
3. A composition for forming a water-repellent film, comprising 3 to 70 parts by weight of the organopolysiloxane having a silanol group represented by the general formula (2).

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<Embodiment 17> The repellent material according to embodiment 16, further comprising (C) an adhesion improver comprising a silane having an epoxy group or an acyloxy group in a proportion of 0.01 to 70 parts by weight. A composition for forming an aqueous film.

Embodiment 18 The water-repellent coating according to embodiment 16, further comprising (D) a curing accelerator comprising a curing catalyst or an organic peroxide in a proportion of 0.01 to 30 parts by weight. Forming composition.

<Embodiment 19> The water-repellent coating according to embodiment 17, further comprising (D) a curing accelerator comprising a curing catalyst or an organic peroxide in a proportion of 0.01 to 30 parts by weight. Forming composition.

In addition, although not enumerated one by one, the present invention
Based on the knowledge of those skilled in the art, various changes, modifications, improvements and the like can be implemented in an aspect,
It goes without saying that all such embodiments are included within the scope of the present invention, without departing from the spirit of the present invention.

[0093]

As is apparent from the above description, the composition for forming a water-repellent film according to the present invention comprises a specific organopolysiloxane and a specific organopolysiloxane having a silanol group in a predetermined ratio. The cured film formed by this composition is intended to achieve a smooth surface, and can achieve excellent water repellency and strength, and particularly excellent workability. Is also exhibited, thereby deforming the substrate after forming the film, even when molding or processing, such a film, cracks and cracks,
The generation of defects such as wrinkles and peeling can be avoided very advantageously.

Therefore, the composition for forming a water-repellent film according to the present invention requires the workability of a cured film at the time of molding or use, in addition to the surface of a material or a part of an article which is often exposed to water or moisture. It can be applied very advantageously to the surface of a member or the like of an article.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tsukasa Kasuga 5-11-3, Shimbashi, Minato-ku, Tokyo Sumitomo Light Metal Industries Co., Ltd. (72) Inventor Akihiro Seiya 5-1-1-3, Shimbashi, Minato-ku, Tokyo No. Sumitomo Light Metal Industries Co., Ltd. PB06 PB07 PC02 PC03 PC04 PC07 PC08 PC10

Claims (4)

[Claims] (A) 100 parts by weight of an organopolysiloxane represented by the following general formula (1):
(B) A composition for forming a water-repellent film, comprising 3 to 70 parts by weight of an organopolysiloxane having a silanol group represented by the following general formula (2). Embedded image Embedded image 2. The water-repellent film formation according to claim 1, further comprising (C) an adhesion improver comprising a silane having an epoxy group or an acyloxy group in a proportion of 0.01 to 70 parts by weight. Composition. 3. The water repellent according to claim 1, further comprising (D) a curing accelerator comprising a curing catalyst or an organic peroxide in a proportion of 0.01 to 30 parts by weight. A composition for forming a film. 4. The composition for forming a water-repellent film according to claim 1, wherein a diluting solvent is added to form a liquid composition.