JP2003105253A - Fluororesin-based coating material composition - Google Patents

Abstract

[57] [Summary] [PROBLEMS] To provide a fluororesin coating composition capable of forming a coating film having excellent weather resistance and excellent antistatic property, dust adhesion property, antibacterial property, and deodorizing property on the surface of the coating film. Offer things. A fluororesin coating composition comprising a fluororesin for paint having a fluorine content of 10% by mass or more and tourmaline powder.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a fluororesin coating composition containing tourmaline powder.

[0002]

2. Description of the Related Art Generally, a coating film obtained from a resin paint is apt to be contaminated with dirt, and there has been a demand for a coating film which is hard to be contaminated both outdoors and indoors. In addition, it has been reported that organic compounds such as formaldehyde impair the health of residents in newly built houses and condominiums, and deodorant properties for removing these organic compounds have also been required. Furthermore, in home electric appliances such as refrigerators, a coating film having antibacterial properties has been required.

By the way, tourmaline (tourmaline) is excellent in antifouling action, deodorizing action, bactericidal action and the like, and in recent years, examples of blending with various resins have been reported. On the other hand, fluororesin-based paints are excellent in weather resistance and the like, and therefore, they are applied to various articles, such as outdoor articles, indoor articles, and home electric appliances. However, since the coating film obtained from the composition for a fluororesin coating material has a property of easily generating static electricity and easily adhering dust and the like, a fluororesin capable of forming a coating film which is difficult to be charged and has good dust resistance A coating composition has been sought.

Japanese Unexamined Patent Publication No. 10-46060 describes a paint having a function of preventing pollution, in which tourmaline fine particles are mixed with a paint applied to the surfaces of partition panels, building interior panels and exterior panels. The publication specifically shows an example in which tourmaline is mixed with an acrylic resin. However, there is no case in which the fine particles of tourmaline are mixed with a fluororesin, and there is no description in the publication that a charging property, which is a problem in a coating film obtained from a fluororesin paint, is reduced. Further, in the specific example described in the publication, it was not possible to provide a coating film to which dust, especially sand dust, is unlikely to adhere.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a fluororesin-based coating composition having good weather resistance and excellent antistatic property, dust adhesion property, antibacterial property, and deodorant property on the coating film surface. To provide.

[0006]

In order to solve the above problems, the fluororesin-based coating composition of the present invention comprises a fluororesin for paint having a fluorine content of 10% by mass or more and tourmaline powder. Is characterized by. The particle diameter of the tourmaline powder is preferably in the range of 0.01 μm to 100 μm. Further, the amount of the tourmaline powder blended is 0.1 with respect to 100 parts by mass of the fluororesin for paint.
It is preferably about 1000 parts by mass.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below.
The fluororesin-based coating composition of the present invention is not limited as long as it has a fluororesin for coating as a main component and tourmaline powder. For example, it may be powder coating, organic solvent solution coating, or aqueous coating. Hereinafter, the form of the powder coating material will be mainly described, but each composition exemplified below can be applied to both a solvent solution system and an aqueous solution system.

In the present invention, the fluororesin for paint as the main component may be any resin containing fluorine and used as the main component of the paint, and various fluororesins for paint can be used. In the present invention, the fluororesin for paint is
It is preferable that the fluorine content is 10% by mass or more.
If the fluorine content in the fluororesin for paints is less than 10% by mass, the weather resistance of the coating film may be insufficient. Further, considering the weather resistance and coating workability of the coating film, the fluorine content in the fluorine resin for coating is more preferably 15 to 72 mass%.

For example, as a fluororesin for paint, a fluororesin containing a fluoroolefin unit and a unit containing a crosslinkable reactive group as essential components is used, and
The curing agent (B) capable of reacting with the crosslinkable reactive groups of the fluororesin to form crosslinks is preferably added as an essential component of the fluororesin coating composition. Fluorine-containing resin
Monomers that are the raw materials for the fluoroolefin unit and monomers that are the raw materials for introducing the crosslinkable reactive group, and, if necessary, these monomers in order to adjust the physical properties or characteristics of the paint or coating film. A fluorinated copolymer (A) obtained by copolymerizing a copolymerizable comonomer is preferable, and a mixture of this fluorinated copolymer (A) and another resin may be used.

The fluorine-containing copolymer constituting the fluorocopolymer (A)
Fluoroolefins and polyfluores
Examples thereof include monomers having a low alkyl group. Fluorine-containing
The monomers may be used alone or in combination of two or more.
You may. Fluoroolefins include vinyl fluoride.
Nyl, vinylidene fluoride, trifluoroethylene, chloro
Rotrifluoroethylene, tetrafluoroethylene,
Fluoropropylene, Hexafluoropropylene, etc.
Is mentioned. Monomer having polyfluoroalkyl group
As CH₂= CR¹COOR²R^f, CH₂= CR¹C
OO (CH₂)_nNR³SO₂R^f, CH₂= CR¹COO
(CH₂) _nNR³COR^f, CH₂= CR¹COOCH₂C
H (OH) (CH₂)_nR^fEtc. However, n
Is an integer from 1 to 10, R^fIs a polyflu having 1 to 18 carbon atoms
The Oroalkyl group is represented by R¹Is a hydrogen atom or a methyl group,
R²Is a divalent organic group having 1 to 6 carbon atoms, R³Is a hydrogen atom
Each represents a monovalent organic group having 1 to 6 carbon atoms. R^fIs
It may be linear or branched, and may have an etheric oxygen atom.
May be included. R^fAs a concrete example of₃, CF₃C
F₂, H (CF₂)₂, CF₃(CF₂)₂, CF₃(CF₂)
₃, H (CF₂)_Four, CF₃(CF₂)_Four, CF₃(C
F₂)_Five, CF₃(CF₂)₂OCF (CF₃), H (CF
₂)₆, CF₃(CF₂)₆, CF₃(CF₂) ₇, H (C
F₂)₈, CF₃(CF₂)₈, CF₃(CF₂)₉, CF₃C
F (CF₃) (CF₂)₆, CF₃(CF₂)_Ten, H (CF
₂)_Ten, CF₃(CF₂)₁₁, H (CF₂)₁₄, CF₃(C
F₂)₁₅, CF₃(CF₂)₁₇Etc. R²The concrete
For example, CH₂, CH₂CH₂, CH (CH₃), CH
₂CH₂CH₂, C (CH₃)₂, CH (CH₂CH₃), C
H₂CH₂CH₂CH₂, CH (CH₂CH₂CH₃), CH₂
(CH₂)₃CH₂, CH (CH₂CH (CH₃)₂) Etc.
You can R³Examples of are hydrogen atom, or C
H₃, CH₃CH₂, CH₃CH₂CH ₂, CH₃CH₂CH₂
CH₂Etc. Fluoroolefins are especially resistant
It is preferable because it has excellent durability.

Examples of the crosslinkable reactive group of the fluorine-containing resin include a hydroxyl group, a carboxyl group, an amide group, an amino group, a glycidyl group, an active halogen such as bromine and iodine, an isocyanate group and a nitrile group. As a method for obtaining the fluorine-containing copolymer (A) into which these crosslinkable reactive groups are introduced, a method of copolymerizing a monomer having a crosslinkable reactive group, a method of decomposing a part of the copolymer, Examples thereof include a method of reacting a compound which gives a crosslinkable reactive group to the functional group of the copolymer.

In the case of the method (1), the monomer having a crosslinkable reactive group is, for example, a monomer having a hydroxyl group or a group capable of being converted into a hydroxyl group, which is copolymerizable with the raw material of the fluoroolefin unit. A compound having a double bond can be used. Specific examples include hydroxyethyl vinyl ether, hydroxypropyl vinyl ether,
Hydroxyalkyl vinyl ethers such as hydroxybutyl vinyl ether, hydroxyisobutyl vinyl ether and hydroxycyclohexyl vinyl ether; hydroxyalkyl vinyl acetate, vinyl hydroxypropionate, vinyl hydroxybutyrate, vinyl hydroxyvalerate, vinyl hydroxyisobutyrate, vinyl hydroxycyclohexanecarboxylate, etc. Esters of carboxylic acid and vinyl alcohol; hydroxyalkyl allyl ethers such as hydroxyethyl allyl ether, hydroxypropyl allyl ether, hydroxybutyl allyl ether, hydroxyisobutyl allyl ether, hydroxycyclohexyl allyl ether; hydroxyethyl allyl ester, hydroxypropyl allyl Esters, Hydroxybu Le allyl ester, hydroxyisobutyl allyl ester, hydroxyalkyl allyl esters such as hydroxycyclohexyl allyl ester;
Examples thereof include hydroxyalkyl esters of acrylic acid or methacrylic acid such as 2-hydroxyethyl acrylate, hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, and hydroxypropyl methacrylate, and partially fluorine-substituted compounds thereof. These can use 1 type (s) or 2 or more types. In particular, vinyl compounds or allyl compounds are preferably used because they have good copolymerizability with the raw material of the fluoroolefin unit.

In the case of the method (1), a monomer having a carboxyl group and having a double bond copolymerizable with the raw material of the fluoroolefin unit can be used. Specific examples include (meth) acrylic acid and carboxyalkyl allyl ether. In the case of the above method, a monomer having an amide group and having a double bond copolymerizable with the raw material of the fluoroolefin unit can be used. Specific examples include (meth) acrylamide and methylol acrylamide. In the case of the above method, a monomer having an amino group and having a double bond copolymerizable with the raw material of the fluoroolefin unit can be used. Specific examples include aminoalkyl vinyl ether and aminoalkyl allyl ether.

In the case of the method (1), a monomer having a glycidyl group and having a double bond copolymerizable with the raw material of the fluoroolefin unit can be used. Specific examples include glycidyl (meth) acrylate, glycidyl vinyl ether, and glycidyl allyl ether. In the case of the above method, a monomer having an active halogen and having a double bond copolymerizable with the raw material of the fluoroolefin unit can be used. Specific examples thereof include vinyl chloride and vinylidene chloride. In the case of the above method, a monomer having an isocyanate group and having a double bond copolymerizable with the raw material of the fluoroolefin unit can be used. Specific examples include vinyl isocyanate and isocyanate ethyl acrylate. In the case of the above method, a monomer having a nitrile group and having a double bond copolymerizable with the raw material of the fluoroolefin unit can be used. Specific examples include (meth) acrylonitrile.

The above-mentioned method for decomposing a part of the copolymer is, for example, by copolymerizing a monomer having a hydrolyzable ester group after the polymerization and then hydrolyzing the copolymer. A method of introducing a carboxyl group into the copolymer is suitable. Alternatively, a cross-linking bond can be formed by a transesterification reaction in a direct curing reaction without performing such hydrolysis.

In the case of the above-mentioned method of reacting the compound which gives a crosslinkable reactive group to the functional group of the copolymer, for example, the hydroxyl group-containing copolymer is reacted with a divalent carboxylic acid anhydride such as succinic anhydride. Therefore, a method of introducing a carboxyl group is preferable. As the monomer that gives a crosslinkable reactive group to the functional group of the copolymer, a vinyl compound or an allyl compound is particularly preferably used because it has good copolymerizability with the raw material of the fluoroolefin unit.

When synthesizing the fluorinated copolymer (A), in addition to the monomer as the raw material for the fluoroolefin unit and the monomer as the raw material for introducing the crosslinkable reactive group, a paint or a coating film. In order to adjust the physical properties or characteristics of the above, a copolymerizable comonomer with these monomers may be copolymerized.

As such a comonomer, one having an unsaturated group active to the extent that it can be copolymerized with the raw material of the fluoroolefin unit and not significantly impairing the characteristics of the coating film is adopted.
Ethylenically unsaturated compounds are preferably used. Specific examples thereof include alkyl vinyl ethers such as ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, isobutyl vinyl ether and cyclohexyl vinyl ether; alkyls such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl valerate and vinyl cyclohexylcarboxylate. Esters of carboxylic acid and vinyl alcohol; alkyl allyl ethers such as ethyl allyl ether, propyl allyl ether, butyl allyl ether, isobutyl allyl ether, cyclohexyl allyl ether; ethyl allyl ester, propyl allyl ester, butyl allyl ester, isobutyl allyl Alkyl allyl esters such as ester and cyclohexyl allyl ester; ethylene, propylene,
Alkenes such as butylene and isobutylene; acrylic acid,
Methacrylic acid or ethyl acrylate, propyl acrylate, butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, and other acrylic acids, methacrylic acid, or esters thereof; Moreover, these partially fluorine-substituted compounds and the like can be mentioned. These are 1 or 2
More than one species can be used.

Of these, vinyl compounds, allyl compounds, and alkenes are particularly preferably used because they have good copolymerizability with the raw material of the fluoroolefin unit. When a vinyl-based or allyl-based alkyl ester or alkyl ether is used, the alkyl group is preferably a linear, branched, or alicyclic alkyl group having about 2 to 10 carbon atoms.

The fluorocopolymer (A) preferably has a fluoroolefin unit content of 70 to 30 mol%. Fluoroolefin unit content is 30 mol%
With the above, the weather resistance can be effectively improved. Further, when the content of the fluoroolefin unit is 70 mol% or less, the fluorine-containing copolymer (A) is likely to be non-crystalline, that is, it is difficult to be crystallized. The smoothness can be improved. Also, high temperature is not required when baking the paint.

When a mixture of the fluorinated copolymer (A) and another resin is used, an acrylic resin is preferable as the other resin because it is excellent in the durability against rain streak contamination. The mixing ratio (mass basis) of the fluorine-containing copolymer / acrylic resin is
Preferably 100/0 to 20/80, more preferably 1
It is 00/0 to 50/50.

Average molecular weight of the copolymer chain per one crosslinkable reactive group present in the molecule of the fluorinated copolymer (A) (molecular weight of the fluorinated copolymer (A) / crosslinking in one molecule) The number of sexually reactive groups) is preferably 250 or more and less than 25,000. If it is 25,000 or more, the crosslinking becomes insufficient, and if it is less than 250, the crosslinking density is too high and the flexibility of the coating film is significantly lowered. The average molecular weight represented by (molecular weight of fluorine-containing copolymer (A) / number of crosslinkable reactive groups in one molecule) is specifically the hydroxyl value and acid value of the fluorine-containing copolymer (A). Alternatively, the crosslinkable reaction group value (mgKOH / g) such as epoxy value can be measured by a method such as IR spectrum, NMR spectrum and titration, and can be calculated by the following formula. In addition, 56.1 in a formula is a molecular weight of KOH. (56.1 / Crosslinkable reactive group value) × 10 ^{3 When} the crosslinkable reactive group is an epoxy group, the epoxy equivalent corresponds to this value.

When the fluorocopolymer (A) has a hydroxyl group as a crosslinkable reactive group, the hydroxyl value is 1 to 200 mg.
KOH / g is preferable, and 20 is particularly preferable.
~ 140 mg KOH / g. If the hydroxyl value of the fluorinated copolymer (A) is less than 1 mgKOH / g, the crosslinking will be insufficient and the physical properties will be reduced to 200 mgKOH / g.
If it exceeds, the crosslink density becomes too high and flexibility decreases.

The intrinsic viscosity of the fluorinated copolymer (A) measured in tetrahydrofuran at 30 ° C. is 0.05.
It is preferably ˜2 dl / g. If the intrinsic viscosity is less than 0.05 dl / g, the fluororesin-based coating composition is unlikely to be solid, and powder coating may not be obtained in some cases. On the other hand, when the intrinsic viscosity exceeds 2 dl / g, the softening point becomes too high and the flowability of the coating film deteriorates.

The glass transition temperature of the fluorinated copolymer (A) is preferably 30 to 120 ° C, more preferably 35 to 100 ° C.
If the temperature is lower than ° C, the fluororesin-based coating composition is unlikely to be a solid, and a powder coating may not be obtained in some cases. On the other hand, when the glass transition temperature exceeds 120 ° C., the softening point becomes too high and the flowability of the coating film deteriorates. Further, it is not preferable to use a crystalline polymer as the fluorine-containing copolymer (A) because a high temperature is required at the time of baking, but when the crystalline polymer is used, the melting point is 200 ° C. The following are preferred.

The fluorinated copolymer (A) can be synthesized by a conventionally known polymerization method. Specifically, the monomers can be polymerized in the presence or absence of a catalyst, by mixing the respective monomers in a predetermined mixing ratio, and by causing a polymerization initiator to act. The polymerization method can be synthesized by any of a solution polymerization method, an emulsion polymerization method and a suspension polymerization method.

When the fluorine-containing copolymer (A) is used as the fluororesin for paint which is the main component of the fluororesin-based coating composition, the curing agent (B) blended in the fluororesin-based coating composition contains It is a compound capable of reacting with the crosslinkable reactive group of the fluorocopolymer (A) to form crosslinks. Specifically, as the curing agent (B), a blocked isocyanate compound, for example, a polyisocyanate compound such as isophorone diisocyanate, tolylene diisocyanate, xylylene diisocyanate, 4,4′-diphenylmethane diisocyanate, hexamethylene diisocyanate; Dimers or trimers; and isocyanate groups of isocyanate compounds such as polyisocyanate compounds obtained by modifying these polyisocyanate compounds with polyhydric alcohols such as trimethylolpropane, ε-caprolactam, phenol, benzyl alcohol, methyl ethyl ketoxime, etc. Blocked isocyanate compounds and the like blocked with the blocking agent described above. As the blocked isocyanate compound, those that are solid at room temperature are preferably used.

Other examples of the curing agent (B) include fumaric acid, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, and other aliphatic dibasic acids; phthalic anhydride, trimetic anhydride, and anhydrous. Acid anhydrides such as pyromellitic acid; dicyandiamide and dicyandiamide derivatives, imidazole and imidazole derivatives, dibasic acid dihydrazides, diaminophenylmethane, amine compounds such as cyclic amidine compounds; melamine resins, terephthalic acid diglycidyl ester, paraoxybenzoic acid diglycidyl Glycidyl compounds such as esters, triglycidyl isocyanate, spiroglycol diglycidyl ether, hydantoin compounds, and alicyclic epoxy resins; 1,
4-bis-2'-hydroxyethoxy benzene, bis-hydroxyethyl terephthalate, styrene-allyl alcohol copolymer, spiro glycol, tris 2-hydroxyethyl isocyanurate, hydroxyl number 10~300mg
Examples thereof include KOH / g, a glass transition temperature of 30 to 120 ° C., a hydroxyl group-containing compound such as a polyester resin or an acrylic resin having a number average molecular weight of 1,000 to 15,000, and the like. As the curing agent (B), a compound that is solid at room temperature is preferably used.

When the fluorocopolymer (A) is used as the fluororesin for paint, the mixing ratio of the fluorocopolymer (A) and the curing agent (B) is (A) :( B) in terms of mass ratio. Is 4
The range of 0:60 to 98: 2 is preferable, and the range of 50:50 to 97: 3 is more preferable.

Examples of tourmaline powder contained in the fluororesin-based coating composition include iron-containing tourmaline, lithium-containing tourmaline, and magnesium-containing tourmaline.
Finely powdered various tourmalines are used by a conventional method. If the particle diameter of the tourmaline powder is too large, the appearance of the coating film will be poor, and if it is too small, sufficient antistatic properties will not be obtained, so it is preferably in the range of 0.01 μm to 100 μm, and preferably 0.05 μm to 50 μm. The range is more preferable. The amount of tourmaline powder blended is 10
It is preferably within the range of 0.1 to 1000 parts by mass, more preferably within the range of 1 to 100 parts by mass with respect to 0 parts by mass. If the content of tourmaline powder in the fluororesin-based coating composition is too low, the addition of tourmaline powder does not sufficiently improve the properties such as antistatic property, dust resistance, antibacterial property and deodorant property. On the contrary, if the content of the tourmaline powder is too large, the weather resistance deteriorates.

The fluororesin-based coating composition can be appropriately blended with additives usually used in coating compositions.
For example, color pigments (eg titanium dioxide, red iron oxide,
Inorganic pigments such as yellow iron oxide and carbon black, and organic pigments such as phthalocyanine blue, phthalocyanine green, quinacridone red pigment, and isoindolinone yellow pigment); extenders such as talc, silica, and calcium carbonate; aluminum powder, stainless steel One kind or two or more kinds of additives such as metal powders such as powders, mica powders, leveling agents, ultraviolet absorbers, heat deterioration inhibitors, antifoaming agents and the like can be blended as desired.

As a method for producing a fluororesin-based coating composition, for example, a fluororesin for a coating (for example, a fluorocopolymer (A)), a curing agent (B), and an additive are blended in a conventional manner. A method in which the tourmaline powder is uniformly mixed with the powder obtained by uniformly mixing and finely pulverizing this mixture can be used. The method of pulverizing the mixture is not particularly limited, but for example, a method of melt-kneading the mixture, cooling and pulverizing can be performed. If the particle size of the powder obtained by the above pulverization is too large, the leveling property is deteriorated and the appearance of the coating film is poor. On the other hand, if the particle size of the powder is too small, it is difficult to control the coating film thickness. Therefore, the particle diameter of the powder is preferably in the range of 0.1 to 200 μm, more preferably 1 to 100 μm.

Alternatively, tourmaline powder is previously mixed in a mixture containing a fluororesin for paint (for example, a fluorocopolymer (A)), a curing agent (B), and an additive, and the mixture is mixed. It is also possible to obtain a fluororesin-based coating composition (powder coating) by pulverizing. Further, the additives may be blended in advance in the fluororesin for paint or the curing agent (B).

The fluororesin-based coating composition (powder coating) thus obtained is suitably used for coating various metals such as iron, aluminum, copper, zinc or alloys thereof, For example, it is possible to form a good coating film by uniformly coating it with a commercially available electrostatic powder coating machine, fluidized dipping device, etc., and then baking it in a hot air oven or the like.

The glass transition temperature of the fluororesin coating composition is preferably 30 to 120 ° C, more preferably 35 to 100 ° C. When the glass transition temperature is lower than 30 ° C., it is hard to be solid and hard to be hardened by heating. On the other hand, when the glass transition temperature exceeds 120 ° C., the softening point becomes too high and the flow of the coating film becomes poor. Further, the weight loss on heating of the fluororesin coating composition is preferably 5% by weight or less, particularly preferably 2% by weight or less. Loss on heating is 5
If it exceeds the weight%, the storage stability of the powder coating is poor,
Further, after baking and curing of the powder coating material, foaming, blistering, pinholes and the like are likely to occur in the coating film, which is not preferable.

According to the fluororesin-based coating composition (powder coating material) of the present invention, the fluororesin for coating material is essentially contained by blending tourmaline powder in the coating composition mainly containing the fluororesin for coating material. Good weather resistance of the coating film obtained, the antistatic property and the dust adhesion property of the coating film surface are improved, and the antibacterial effect and the deodorizing effect of the coating film are also obtained. In particular, if the fluorine content of the fluororesin for paints is 10% by mass or more, good weather resistance can be obtained, and the incorporation of tourmaline powder makes it difficult for dust, particularly sand dust, to adhere to the surface of the coating film. It is preferable because the effect of becoming

Further, the fluororesin coating composition of the present invention comprises
It may be an organic solvent solution-based paint having a solvent-soluble fluororesin for paint as a main component. In this case, as the tourmaline powder, the same ones as in the above embodiment can be used, and as the solvent, for example, aromatic hydrocarbons such as xylene and toluene; alcohols such as n-butanol; butyl acetate and the like. Esters; ketones such as methyl isobutyl ketone; glycol ethers such as ethyl cellosolve; commercially available thinners and the like can be used. The curing agent may be a heat curing type curing agent or a room temperature curing type curing agent. For example, if a heat-curing type curing agent is previously mixed in the coating composition, a one-pack type coating material is obtained, and if it is a room-temperature curing type curing agent, it is prepared separately from the coating composition and a two-pack type Used as paint. Further, if necessary, the same additives as those in the above-mentioned embodiment can be appropriately mixed.

The organic solvent solution-based coating material according to the present invention contains one or more kinds of fluororesin as a main component, tourmaline powder, a solvent, and if necessary, a curing agent and an additive,
It is obtained by uniform mixing according to a conventional method. The method of blending the tourmaline powder is not particularly limited, and powdery ones may be added, and the tourmaline powders may be previously dispersed in an appropriate liquid to give a gel, or a liquid one may be added. May be.

The fluororesin-based coating composition of the present invention comprises
It may be an aqueous solution-based paint containing a water-soluble fluororesin for paint as a main component. In this case, as tourmaline powder,
The same thing as the above-mentioned embodiment can be used. The curing agent may be a heat curing type curing agent or a room temperature curing type curing agent. For example, if a heat-curing type curing agent is previously mixed in the coating composition, a one-pack type coating material is obtained, and if it is a room-temperature curing type curing agent, it is prepared separately from the coating composition and a two-pack type Used as paint. Further, if necessary, the same additives as those in the above-mentioned embodiment can be appropriately mixed.

The aqueous solution paint according to the present invention comprises at least one fluororesin for paint as a main component, tourmaline powder, water,
It can be obtained by adding a curing agent and additives as needed and mixing them uniformly by a conventional method. The method of blending the tourmaline powder is not particularly limited, and powdery ones may be added, and the tourmaline powders may be previously dispersed in an appropriate liquid to give a gel, or a liquid one may be added. May be.

The fluororesin-based coating composition of the present invention, whether it is an organic solvent solution-based coating or an aqueous solution-based coating, is mainly composed of a fluororesin for coating as in the powder coating of the above-mentioned embodiment. By blending tourmaline powder into the coating composition as a component, good weather resistance of the coating film that the fluororesin for coating originally has can be obtained, and the coating surface has antistatic property and dust resistance. The property is improved, and the antibacterial effect and the deodorant effect in the coating film are also obtained.

[0042]

EXAMPLES The effects of the present invention will be clarified below with reference to specific examples. First, an example of synthesizing a fluorinated copolymer (A) using the monomers shown in Table 1 below is shown.

[0043]

[Table 1]

[Synthesis Example 1 of Fluororesin for Paint] Contents 30
In a pressure resistant reactor equipped with a stirrer, made of 0 ml slene, 157 g of t-butanol, cyclohexyl vinyl ether (C
16 g of TFE, isobutyl vinyl ether (iBV
E) 9 g, hydroxybutyl vinyl ether (HBV
E) 25 g, potassium carbonate 1 g, and azobisisobutyronitrile (AIBN) 0.07 g were charged, and dissolved oxygen was removed by solidification degassing with liquid nitrogen. Then, 50 g of chlorotrifluoroethylene (CTFE) was introduced, and the temperature was gradually raised. The reaction was continued under stirring while maintaining the temperature at 65 ° C., and after 10 hours, the reactor was water-cooled to stop the reaction. After cooling to room temperature, unreacted monomer was purged to open the reactor, filtration was performed with diatomaceous earth, and then the solvent was removed under reduced pressure to obtain a fluorocopolymer (resin) A-1. The fluorine content of the obtained fluorine-containing copolymer A-1,
The values of hydroxyl value, glass transition temperature, and intrinsic viscosity measured at 30 ° C. in tetrahydrofuran are also shown in Table 1.

[Fluorine Resin Synthesis Examples 2 to 6 for Paint] In the above-mentioned Fluorine Resin Synthesis Example 1 for paint, the monomer composition was changed as shown in Table 1, and t-butanol (solvent) and AIBN (polymerization) were used. Fluorine-containing copolymers (resins) A-2 to 6 were respectively obtained in the same manner as in the above-mentioned fluororesin synthesis example 1 for coating materials, except that the amount of the initiator used was appropriately changed.
The fluorine content of the obtained fluorine-containing copolymer A-2 to 6,
The values of hydroxyl value, glass transition temperature, and intrinsic viscosity measured at 30 ° C. in tetrahydrofuran are also shown in Table 1.

[Examples 1 to 12] A resin, tourmaline powder, a curing agent, an additive, and a pigment were blended in the blending ratios shown in Tables 2 to 3 below, and a dry blender (manufactured by Mitsui Kakoki, trade name: (Henschel mixer) for 1 minute to uniformly mix, and then melt-kneaded using an extrusion kneader (Bus Co., product name: Busconieder) at a temperature of 80 to 100 ° C., cooled, and then finely ground with a hammer mill. did. Then, 15
The powder coating was obtained by filtering through a 0 mesh wire mesh. The powder coating thus obtained was applied to a 0.8 mm-thick zinc phosphate-treated iron plate using an electrostatic powder coating gun (manufactured by Onoda Cement Co., Ltd., product name: GX-501) at a voltage of 70 KV. Electrostatic coating was performed for 4 minutes under the conditions of a powder discharge rate of 100 g / min, a temperature of 20 ° C. and a humidity of 60%. Furthermore, 20 at 190 ℃
After baking for a minute, a cured coating film of about 40 μm was obtained. The evaluation results of the obtained coating film are shown in Tables 2 and 3. In addition, Examples 1 to 9 are Examples and Examples 10 to 12 are Comparative Examples. Tables 2-3
The evaluation items described in 1 above were measured according to the following methods.

[Examples 13 to 17] Resins, tourmaline powder, curing agents, additives, and pigments were dissolved in appropriate solvents at the compounding ratios shown in Tables 3 to 4 below to obtain solvent-based paints. The obtained coating material was applied onto a 0.8 mm thick zinc phosphate-treated iron plate and then dried to obtain a cured coating film of about 40 μm. The evaluation results of the obtained coating film are shown in Tables 3-4.
In addition, Examples 13 and 14 are Examples, and Examples 15 to 17 are Comparative Examples. The evaluation items described in Tables 3 and 4 were measured according to the following methods.

Antistatic property: A triboelectrification test was conducted on the surface of the coating film by using a rotary static tester (Koa Shokai Co., Ltd.) based on JISL-1094. When the voltage was greatly reduced compared to the surface of the coating film obtained by the coating material containing no tourmaline powder, it was marked with ◯. On the other hand, when the voltage did not drop significantly compared to the surface of the coating film obtained by the powder coating material containing no tourmaline powder, it was marked with x. In Tables 2, 3, and 4, Examples 1 to 9 are compared with Example 10, Example 11 is compared with Example 12, Examples 13 and 14 are compared with Example 15, and Example 16 is Example 17. Compared with. Dust resistance: Yellow ocher (Holbein Kogyo Co., Ltd., main component Fe2O3: 20.7% Al2O3: 2)
0.7% SiO2: 54.0% CaCO3: 0.4
%) Was evenly sprinkled on the coated plate using a sieve until the surface could not be seen, and the back surface of the coated plate was evenly tapped with a scoop to remove dirt substances. After the above operation was repeated 5 times, the degree of adhesion of yellow ocher on the surface of the coating film was visually evaluated. The case where almost no yellow ocher adhered to the surface of the coating film was marked with ◯, and the case where the yellow ocher adhered to the entire surface of the coating film was marked with x.

Antibacterial property: The coated plate is bent and cut,
A cubic container having one side of 90 mm was prepared. After leaving the mochi to which no preservative was added for 30 minutes in the air, the surface of the rice cake that was in contact with the air surface (hereinafter referred to as surface A) was attached to the coated surface of the container, and wrap (polyenca Vinylidene film), and seal under conditions of 20 ° C and 50% humidity.
After leaving for a week, the condition of the surface A of the rice cake was evaluated. The case where the mold was not found on the surface A of the rice cake was described as O, and the case where the mold was found on the surface A of the rice cake was described as X. Deodorant property: A coated plate was bent and cut to prepare a cubic container having a side of 1 m. Formaldehyde 100pp
After 24 hours, the gas concentration in the container was measured by a gas detector. When the concentration of formaldehyde was significantly reduced from the initial state, it was described as ◯, and when it was almost the same as the initial state, it was described as x. Accelerated weather resistance: The gloss retention after 4000 hours of the carbon arc lamp type accelerated weather resistance test described in JIS K5400 9.8.1 was measured. A gloss retention rate of 80% or more was described as ◯, and a gloss retention rate of less than 80% was described as.

[0050]

[Table 2]

[0051]

[Table 3]

[0052]

[Table 4]

[0053]

As described above, according to the fluororesin-based coating composition of the present invention, the combination of tourmaline powder with the fluororesin for coating having a fluorine content of 10% by mass or more provides good weather resistance. And a fluororesin-based coating composition that forms a coating film having excellent antistatic property, dust resistance, antibacterial property, and deodorant property.

Continued front page    F term (reference) 4J038 CB021 CB022 CB091 CB092                       CB131 CB132 CC021 CC022                       CD091 CD101 CD102 CD111                       CD112 CD121 CD122 CD131                       CD132 CE011 CE012 CE051                       CE052 CF051 CF052 CF091                       CF092 CG031 CG141 CG171                       CG172 CH031 CH041 CH042                       CH251 DB091 DB092 DD001                       DD002 DG301 DG302 GA06                       GA07 GA08 GA10 GA12 HA556                       JA75 JB07 JB17 JB18 JB32                       MA12 MA13 MA15 NA05 NA17                       NA27

Claims (3)

[Claims] 1. A fluororesin coating composition comprising a fluororesin for paint having a fluorine content of 10% by mass or more and tourmaline powder. 2. The particle size of the tourmaline powder is 0.01
The fluororesin-based coating composition according to claim 1, wherein the fluororesin-based coating composition is in the range of μm to 100 μm. 3. The amount of the tourmaline powder blended is 0.1 to 1000 with respect to 100 parts by mass of the fluororesin for paint.
It is a mass part, The fluororesin type coating composition of Claim 1 or 2 characterized by the above-mentioned.