JPH02286759A - Coating composition - Google Patents

Abstract

PURPOSE:To obtain a coating composition which can give a coating film improved in surface hardness, gloss, solvent resistance, staining resistance, light resistance, nonstickiness, etc., by mixing a film-forming fluororesin modified with a specified modifying agent. CONSTITUTION:A reactive organic functional group-containing fluorine compound of any one of formulas I-III (wherein R is F or CF3; and n is 4-13) is reacted with a reactive organic functional group-containing siloxane compound (e.g. amino-terminated propylpolydimethylsiloxane) and an organic polyisocyanate in the absence or presence of an organic solvent and a catalyst at 0-150 deg.C for 10min to 3hr to obtain a modifying agent having at least one free isocyanate group. 0.0001-1 pt.wt. curing agent (e.g. hexamethylene diisocyanate) is added to 100 pts.wt. coating material obtained by mixing 5-30wt.% this fluororesin with 95-50wt.% solvent and optionally an extender pigment, an organic pigment, a plasticizer, a UV absorber, etc.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a coating composition, and more particularly to a coating composition that is curable at room temperature and forms a coating film with excellent surface properties, particularly a fluorine-containing resin coating. Regarding the composition.

(Prior art and its problems) Conventionally, paints have been applied to the surfaces of various structures, buildings, articles, etc., to prevent corrosion and deterioration of the objects to be coated, and to protect these structures and articles. It is widely used to give a good appearance.

Various types of paints are known as such protective and cosmetic paints, but in recent years, fluorine-containing resin paints have been widely used as paints with excellent durability such as weather resistance and stain resistance. It has become.

However, although fluorine-containing resins inherently have excellent weather resistance, heat resistance, water repellency, chemical resistance, electrical properties, etc., they are not soluble in many paint solvents, so they are used only for very special purposes. It has been.

In order to solve these drawbacks, recently, fluorine-containing polymers that are soluble in common paint solvents have been developed by copolymerizing fluorine-containing monomers with common monomers, and some of them are used for paints. However, as a result of these resins having a general non-fluorine-containing monomer moiety, it was inevitable that the excellent properties inherent to fluorine-containing resins, such as stain resistance, abrasion resistance, non-adhesiveness, and lubricity, would deteriorate. .

Therefore, the object of the present invention is to provide a copolymer of a fluorine-containing monomer and a non-fluorine-containing monomer, which has good solubility in general paint solvents, yet has various excellent properties inherent to fluorine-containing resins. An object of the present invention is to provide a coating composition that provides a film having the following properties.

(Means for solving problems) The above objects are achieved by the present invention as described below.

That is, the present invention relates to a reaction product of a fluorine compound and a polysiloxane compound having a reactive organic functional group and an organic polyisocyanate, the fluorine-containing product being modified with a modifier having at least one free isocyanate group. This is a coating composition characterized by containing a resin as a film-forming component.

(Function) A film-forming fluorine-containing resin is mixed with a fluorine compound having a reactive organic functional group and a polysiloxane compound coCFsCF (CFil.C00H (n=4 to 13) (4)I CF, CF [GFal, IC2H4SH ( n= 4 to 13)H (n・4 to 13.0=0 to 6, p・0 to 3, q=
1 to 3) and an organic polyisocyanate, which has good solubility in general paint solvents by being modified with a modifier having at least one free isocyanate group. , it is possible to provide a coating composition that provides a film having various excellent properties inherent to fluorine-containing resins.

(Preferred Embodiments) Next, the present invention will be described in more detail by citing preferred embodiments.

The modifier used in the present invention and which mainly characterizes the present invention is a reaction product of a fluorine compound having a reactive organic functional group and a polysiloxane compound with an organic polyisocyanate, which contains at least one free incyanate. It has a base.

Preferred examples of the fluorine compound having a reactive organic functional group used in the present invention include the following compounds.

(1)l HCF2CF(CF21,1CH20H(n") In the structural formula of 2 to 101 or more, R represents F or CF.

In addition, preferred examples of the siloxane compound having a reactive organic functional group used in the present invention include the following compounds.

(1) Amino modified siloxane oil (I11=1 to 1 mouth, n=2 to 1 O1R=CH3 or OCHsl (m=1 to 10, n=2 to 10, R=
(:H3 or OCHs) (m・0 to 200) 11a (n・2 to 10) (branch point 2 to 3, R lower alkyl group, 1-2 to 200. 2 to 200. 2 to 200) ( n=1 to 200, R/lower alkyl group) (2) Epoxy modified siloxane oil (n=1 to 200) (m=1 to 10, n・2 to 10) Alcohol modified siloxane oil (n・1 to 20D) (m=1 to 10, n=2 to 10) (n=0 to 200) (1=1 to 10, m=10 to 200, n・1 to 5
) (n; 1 to 200, lower alkyl) (n = 1 to 200) (branch point 2 to 3, lower alkyl group, 1 = 2 to 200, m 2 to 200, n = 2 to 200) ( 1 to 10) (m: 1 to 10, n=2 to 10) The above epoxy compound can be used by reacting with a polyol, polyamine, polycarboxylic acid, etc. to have active hydrogen at the end.

(R=lower alkyl group, hydrogen atom, alkyl group, K=1 to 250, ■・0 to 5, m=0 to 50, n
= 1 to 3) (R = lower alkyl group, hydrogen atom, alkyl group, k = 1 to 250.1; 0 to 5, m = o to 50, n
= 2 to 3) Mercapto-modified siloxane oil (m = 1 to 1O1 n = 2 to 10) +13 (n = 2 to 10) (branch point, 2 to 3.R, lower alkyl group, n = 2 to 200, m=2 to 2oo, n=2 to 200) (n=
1 to 200, R/lower alkyl group) (5) Carboxyl-modified siloxane oil (n+=1 to 1O1n=
2 to 10) (n=1 to 200) 4-isopropyl-1,3-phenylene diisocyanate, 4-chloro-1,3-phenylene diisocyanate, 4-butoxy-1,3-phenylene diisocyanate, 2,4-diisocyanate- Diphenyl ether, methylene diisocyanate, 4.4-methylenebis(phenylisocyanate), shrylene diisocyanate, 1.5-naphthalene diisocyanate, benzidine diisocyanate, 0-nitrobenzidine diisocyanate, 4.4-dibenzyl diisocyanate, 1.4-tetramethylene diisocyanate , 1.6-tetramethylene diisocyanate, 1.10-decamethylene diisocyanate, 1.4
-Cyclohexylene diisocyanate (branch point, 2 to 3.R, lower alkyl group, 1=2 to 200, m=
2 to 200, n・2 to 200) (n・1 to 200, R″=lower alkyl group) The above two types of compounds having a reactive organic functional group are examples of preferred compounds in the present invention. However, the present invention is not limited to these examples (the above-mentioned exemplified compounds and other compounds are currently commercially available and can be easily obtained from the market, and any of them can be used in the present invention). It is possible.

As the organic polyisocyanate to be reacted with the above-mentioned fluorine compound and polysiloxane compound, any conventionally known organic polyisocyanate can be used, but preferred examples include toluene-2,4-diisocyanate and 4-methoxy-diisocyanate.
Examples include 1,3-phenylene diisocyanate, xylylene diisocyanate, 4,4-methylenebis(cyclohexyl isocyanate), and 1,5-tetrahydronaphthalene diisocyanate.

Further examples include adducts of these organic polyisocyanates and other compounds, such as those having the following structural formulas, but are not limited thereto.

By making a urethane obtained by reacting COCH3 or these organic polyisocyanates with a low molecular weight polyol or polyamine to form a terminal isocyanate, it is advantageous because the resulting solution can be used as it is for modifying fluorine-containing resins. It is.

Any organic solvent that may be used in the production of such a modifier may be used as long as it is inert to the respective reaction raw materials and products.

Preferred organic solvents include methyl ethyl ketone, methyl-n-propyl ketone, methyl isobutyl ketone, diethyl ketone, methyl formate, ethyl formate,
Propyl formate, methyl acetate, ethyl acetate, butyl acetate, etc. Also, acetone, cyclohexane, tetrahydrofuran, dioxane, methanol, ethanol, isopropyl alcohol, butanol, toluene, xylene,
Dimethylformamide, dimethyl sulfoxide, perchlorethylene, trichlorethylene, methyl cellosolve, butyl cellosolve, cellosolve acetate, etc. can also be used.

As the fluorine-containing resin used as the film-forming resin in the present invention and modified with the above-mentioned modifier, it is possible to use, of course, Icyanelle polymer and the like.

The modifier used in the present invention is a fluorine compound and a polysiloxane compound having a reactive organic functional group as described above, and an organic polyisocyanate as described above. , in the presence or absence of an organic solvent and a catalyst, at a functional group ratio such that one or more isocyanate groups are in excess, preferably 1 to 2, in one molecule, from about 0 to 150°C, preferably from 20 to 80°C. It can be easily obtained by reacting at a temperature of .degree. C. for about 10 minutes to 3 hours.

The reaction is a reaction between a fluorine compound and a polyisocyanate,
The polysiloxane compound and the polyisocyanate may be reacted separately, and the resulting modifiers may be mixed before and after preparing the paint, or the fluorine compound and the polysiloxane compound may be reacted with the polyisocyanate at the same time. A modifying agent may be prepared by reaction and used without particular limitation.

The modifier may be prepared in a solvent or without a solvent, but in terms of process, it must have a group that reacts with the modulating group in an organic solvent and be soluble in the solvent. Various fluororesins containing these are commercially available, and any of these commercially available fluororesins can be used in the present invention.

An example of a suitable fluorine-containing resin is a fluorine-containing olefin monomer such as tetrafluoroethylene or trifluorochloroethylene, and a hydroxyl group, a carboxyl group, an amino group,
It is a copolymer with a monomer having a functional group reactive with isocyanate groups, such as an acid anhydride group, an epoxy group, or a thioalcohol group, or it may be one in which these reactive groups are added after copolymerization. . Typical examples of these copolymerizable monomers include vinyl acetate, vinyl ester, (meth)acrylic acid, and various esters thereof. Of course, during copolymerization, a third monomer having no reactive group may be copolymerized. The copolymerization ratio of the fluorine-containing monomer and other monomers is such that the resulting copolymer is soluble in general paint solvents. For example, the molar ratio of the fluorine-containing monomer in the copolymer is 30 to 90. The paint solvent used in the present invention, which is preferably in the range of %, is a solvent commonly used in paints, and includes, for example, the solvents exemplified above.

The coating composition of the present invention has the above-mentioned components as essential components, and their blending ratio is such that the total solid content of the solvent is 5 to 50% by weight, and the film-forming fluorine-containing resin is 1% of the coating material.
○The range accounts for about 5 to 30% by weight in the weight part,
The modifier is used in an amount of 1 to 10 parts per 100 parts by weight of the fluororesin.
A range of 0 parts by weight is preferred. The reaction between the modifier and the fluorine-containing resin may be carried out before or after the preparation of the coating material, and is not particularly limited.

Furthermore, the coating composition of the present invention, like other general coatings,
Extender pigments, organic pigments, inorganic pigments, other film-forming resins,
Plasticizers, ultraviolet absorbers, antistatic agents, leveling agents, curing agents, catalysts, etc. can be included as necessary.

Other general film-forming resins that may be used in combination include, for example, various conventionally known film-forming resins, and when the coating composition of the present invention is to be cured at room temperature, for example, amine-based resins. Approximately 0 per 100 parts by weight of paint, such as organometallic catalysts.
．． It is preferable to add and mix in a proportion of 0,001 to 1 part by weight.

The method for producing the coating composition of the present invention itself may be the same as the conventional technique and is not particularly limited.

(Effects) The paint of the present invention as described above can be applied to steel plates, aluminum plates, aluminum sash, etc., metal structures, glass, cement, inorganic structures such as concrete, wood, FRP, polyethylene, etc.
It is useful for the protection and cosmetic coating of plastic structures such as polypropylene, nylon, polyester, vinyl chloride resin, ethylene vinyl acetate resin, acrylic resin, etc., and has excellent surface hardness, gloss, solvent resistance, stain resistance, light resistance, and A coating film with excellent adhesiveness etc. can be provided.

Such effects are due to the fact that the deterioration of various properties of the fluorine-containing resin due to copolymerization with other monomers is compensated for by modification with a fluorine- and/or siloxane-containing modifier.

Any of these can be used, for example, vinyl chloride resin, vinylidene chloride resin, vinyl chloride/vinyl acetate/vinyl alcohol copolymer resin, alkyd resin, epoxy resin, acrylonitrile-butadiene resin, Examples include polyurethane resins, polyurea resins, nitrocellulose resins, polybutyral resins, polyester resins, melamine resins, urea resins, acrylic resins, polyamide resins, etc. Especially those containing isocyanate groups in their structures. A resin having a reactive group capable of reacting with is preferably used. These resins can be used alone or as a mixture, and can be used as a solution or dispersion in an organic solvent.

In addition, various substances can be used as the crosslinking agent or curing agent, but preferred are the polyisocyanate compounds mentioned above, and non-yellowing discoloration diisocyanates such as hexamethylene diisocyanate and isophorone diisocyanate, as well as adducts thereof, are particularly useful. It is.

Addition of these polyisocyanates as curing agents (Examples) Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples. It should be noted that unless otherwise specified, the terms in the text or % are based on weight.

Reference Example 1 (Production of Modifier) 32.3 parts of hexamethylene diisocyanate and 0.01 part of dibutyltin dilaurate were added to 155 parts of ethyl acetate, and while stirring well at 80°C, a terminal aminopropyl polyamide having the following structure was added. 300 parts of dimethylsiloxane (molecular weight 1,560) was gradually added dropwise to cause a reaction.

(n is the value at which the molecular weight is 1,560) After the reaction was completed, ethyl acetate was removed by evaporation to obtain 328 parts of transparent liquid modifier (I).

According to the infrared absorption spectrum, the above modifier has 2.2.
Absorption due to free isocyanate groups was observed at 70 cm-', and an absorption band based on Sl-0- groups was observed at 1,090 cm-'. Furthermore, when the number of free isocyanate groups in this modifier was determined, the theoretical value was 2.43%, whereas the actual value was 2.30%.

Therefore, the main structure of the above modifier is estimated to be the following formula.

Reference Example 2 (Production of Modifier) 15.1 parts of isophorone diisocyanate and 0.005 parts of dibutyltin dilaurate were added to 70 parts of ethyl acetate.
0'C (While stirring, add polydimethylsiloxane (molecular weight 2.20
0) was gradually added dropwise to react.

(n is the value that makes the molecular weight 2,200) I let it happen.

After the reaction was completed, ethyl acetate was removed by evaporation to obtain 194 parts of transparent liquid modifier (III).

According to the infrared absorption spectrum, the above modifier has 2.27
Absorption due to free isocyanate groups was observed at 0 cm-', and an absorption band based on 13i-0- groups was observed at 1,090 cm-'. When the group was quantified, the theoretical value was 1.70%.
However, the actual value was 1.58%.

Therefore, the main structure of the above modifier is estimated to be the following formula.

Reference Example 4 (Production of Modifier) Add 62 parts of hexamethylene diisocyanate and 0.008 parts of dibutyltin dilaurate to 272 parts of ethyl acetate. While stirring at <80°C, add 210 parts of fluorinated alcohol having the following structure to the mixture. After the reaction was completed, ethyl acetate was removed by evaporation to obtain 162 parts of transparent liquid modifier (II).

According to the infrared absorption spectrum, the above modifier has 2.27
Absorption due to free isocyanate groups was observed at 0 cm-', and an absorption band based on -3i-0- groups was observed at 1,090 cm-. Furthermore, when the amount of free incyanate groups in this modifier was quantified, the theoretical value was 1.73%, whereas the actual value was 1.61%.

Therefore, the main structure of the above modifier is estimated to be the following formula.

Reference example 3 (manufacture of modifier) 21.4 parts of water-added MDI and dibutyl tin dilaure) 0
．． 006 parts of ethyl acetate was added to 86 parts of ethyl acetate, and while stirring well at 80°C, 180 parts of polydimethylsiloxane (molecular weight 2,200) having the same terminal hydroxyl group as in Example 2 was gradually added dropwise to the mixture, and the reaction was gradually added dropwise. and reacted.

CF3CF (GHzl 7cHzcHJH/CF3) After the reaction was completed, ethyl acetate was removed by evaporation to obtain 264 parts of milky white wax-like modifier (IV).

According to the infrared absorption spectrum, the above modifier has 2.27
Absorption due to free isocyanate groups was observed at 0 cm-', and an absorption band based on -Ch- groups was observed at 1,190 cm-'. Furthermore, when the amount of free isocyanate groups in this modifier was quantified, the theoretical value was 5.73%, but the actual value was 5.21%.

Therefore, the main structure of the above modifier is estimated to be the following formula.

Reference example 5 (manufacture of modifier) 71 parts of isophorone diisocyanate and 0.006 parts of dibutyltin dilaurate were added to 221 parts of ethyl acetate and 80 parts of ethyl acetate were added.
150 parts of fluoroalcohol having the structure shown below was gradually added dropwise to the mixture while stirring well at a temperature of 0.degree. C. to cause a reaction.

CFs (CF2) tcHzcHzOH After completion of the reaction,
Ethyl acetate was removed by evaporation and a milky waxy modifier (V
) 214 parts were obtained.

According to the infrared absorption spectrum, the above modifier has 2.27
Absorption due to free isocyanate groups was observed at 0 cm-', and an absorption band based on CF2- groups was observed at 1,190 cm-'. Furthermore, when the amount of free incyanate groups in this modifier was quantified, the actual value was 5.80%, while the theoretical value was 6.12%.

Therefore, the main structure of the above modifier is estimated to be the following formula.

Reference Example 6 (Production of Modifier) Reference Example 7 (Production of Modifier) Adduct of hexamethylene diisocyanate and water (Dilaurate 24A-100, manufactured by Asahi Kasei, NCO% = 23.
5%) and 0.007 parts of dibutyltin dilaurate were added to 246 parts of ethyl acetate, and while stirring well at 80°C, 164 parts of the polysiloxane used in Reference Example 2 was gradually added dropwise thereto to react. Subsequently, 42 parts of the fluorine alcohol used in Reference Example 4 was gradually added dropwise at the same temperature to cause a reaction.

After the reaction was completed, ethyl acetate was removed by evaporation to obtain 237 parts of a milky white wax-like modifier (■).

According to the infrared absorption spectrum, the above modifier has 2.27
Absorption due to free isocyanate groups was observed at 0 cm-', and absorption bands based on -0F2- and -81-0- groups were observed at 1,190 cm- and 1.090 cm-'. In addition, 98 parts of fluorine-added MDI and 0.009 parts of dibutyltin dilaurate in this modifier were mixed with 31 parts of ethyl acetate.
In addition to 8 parts, 220 parts of fluorine alcohol having the following structural formula was gradually added dropwise to the solution while stirring well at 80° C. for reaction.

After the reaction was completed, ethyl acetate was removed by evaporation to obtain 308 parts of milky white wax-like modifier (VI).

According to the infrared absorption spectrum, the above modifier has 2.27
Absorption due to free isocyanate groups was observed at 0 cm-', and an absorption band based on CF2- groups was observed at 1,190 cm-'. Furthermore, when the amount of free isocyanate groups in this modifier was quantified, the theoretical value was 4.95%, whereas the actual value was 4.52%.

Therefore, the main structure of the above modifier is estimated to be the following formula.

When the isocyanate group of Li was quantified, the theoretical value was 1.
．． 30%, whereas the actual value was 1.21%.

Therefore, the main structure of the above modifier is estimated to be the following formula.

Reference Example 8 (Modification of resin) Fluoroolefin-vinyl ether copolymer resin solution (
Solid content 50%, hydroxyl value 24 mgKOH/g, manufactured by Asahi Glass) 300 parts, 4 parts modifier (■) and modifier (IV)
3 parts were added and reacted at 80° C. for 7 hours to obtain a fluorine-containing resin solution modified with a modifier.

In this modified resin, no incyanate group was observed by infrared absorption spectrum. This is presumed to be due to graft bonding of the modifier to the resin.

Reference Example 9 (Modification of resin) Fluoroolefin-vinyl ether copolymer resin solution (
Solid content 60%, hydroxyl value 32 mgKOH/g, Asahi Glass) 300 parts, 5 parts modifier (■) and 3 parts modifier (■)
The mixture was reacted at 80° C. for 7 hours to obtain a fluorine-containing resin solution modified with a modifier.

In this modified resin, no incyanate group was observed by infrared absorption spectrum. This is presumed to be due to craft bonding of the modifier to the resin.

Reference Example 10 (Modification of resin) Fluoroolefin-vinyl ether copolymer resin solution (
Solid content 50%, hydroxyl value 26 mgKOH/g, manufactured by Asahi Glass) 300 parts, 5 parts modifier (■) and modifier (VI)
3 parts were added and reacted at 80° C. for 7 hours to obtain a fluorine-containing resin solution modified with a modifier.

In this modified resin, no incyanate group was observed by infrared absorption spectrum. This is presumed to be due to graft bonding of the modifier to the resin.

Reference example 11 (Modification of resin) Table 1 (Coating composition) Resin: Resin 12: Titanium: Curing agent: Modified resin (solid content 50%) Unmodified resin (solid content 50%) Titanium oxide CR-90 Coronate EH (8 parts of modifier (■) was added to 300 parts of the fluoroolefin-vinyl ether copolymer resin solution of Japan Polyurethane Reference Example 10, and the mixture was heated to 80°C.
The mixture was reacted for 5 hours to obtain a fluorine-containing resin solution modified with a modifier.

In this modified resin, no isocyanate groups were observed by infrared absorption spectrum. This is presumed to be due to graft bonding of the modifier to the resin.

Examples 1 to 4 and Comparative Examples 1 to 3 The modified resin solutions of Reference Examples 8 to 11 were made into paints according to the formulations shown in Table 1 below based on a conventional coating method, and applied to a zinc steel plate (treated with phosphoric acid) to a dry thickness of 25 μm. Apply at a rate of 130°C
/1m1n and 25°C/1 day to form respective films.The various physical properties of each film were measured, and the results shown in Table 2 below were obtained.

In addition, Comparative Examples 1 to 3 are cases where the fluorine-containing resin solutions used in Reference Examples 8 to 10 before modification were made into paints as they were.

catalyst: made) Dibutyltin dilaurate (modifier) Considering the amount added during production of (Adjusted so that the final amount is the same) (Coating film physical properties) Gloss = 60° gloss Adhesiveness: Separate adhesive cellophane tape Stain resistance: Lipstick, crayon: Wipe off with a dry cloth Magic: Used black and red.

*1 = Wipe off with a dry cloth *2 = Wipe off with a mixed solvent of petroleum benzene/ethanol (weight ratio 1/1) Judgment Criterion 202: No trace left at all.

O = Slightly marks left × = Surface quality completely leaves marks: Water repellency criteria 20 = Well repelled ○ = Relatively well repelled Falling angle (°): When the coating material is tilted, Angle at which water droplets begin to slide (using a contact angle meter from Kyowa Interface Materials ■) Peeling the cellophane tape: JIS (2107) Measure the peeling force (g/lri'') 3 days after adhering JIS (2107) to the cellophane tape at a constant pressure at 25°C (g/lri'') Applicant Dainichiseika Kagyo Co., Ltd. (1 other person)

Claims (2)

[Claims] (1) Coating of a fluorine-containing resin modified with a modifier having at least one free isocyanate group, which is a reaction product of a fluorine compound and a polysiloxane compound having a reactive organic functional group and an organic polyisocyanate. 1. A coating composition characterized by containing it as a forming component. (2) The coating composition according to claim 1, further comprising a curing agent.