KR20210126711A - Fluoro rubber coating compositions and coating articles - Google Patents

Abstract

Provided is a coating composition that provides a coating film that is less likely to be removed from a substrate and exhibits small compression set. A fluororubber, a polyol-based vulcanizing agent, an amino group-containing metal compound and an organic solvent are included, and 0.1 to 4.99 parts by mass of the polyol-based vulcanizing agent and the amino group-containing metal compound are included in total with respect to 100 parts by mass of the fluororubber. A fluororubber coating composition comprising

Description

Fluoro rubber coating compositions and coating articles

The present disclosure relates to a fluororubber coating composition and a coated article.

Fluorine rubber is used for coatings other than molded products by using its excellent heat resistance, oil resistance, solvent resistance, and chemical resistance. , is widely used as an industrial material.

Patent Document 1 describes a paint containing fluororubber, a polyol-based vulcanizing agent, an amino group-containing metal compound of 15 parts by weight based on 100 parts by weight of the fluororubber, methyl isobutyl ketone, and the like.

Patent Document 2 describes a paint containing fluororubber, a polyol-based vulcanizing agent, propylene glycol diacetate (thickener), methyl isobutyl ketone (good solvent), isoparaffinic solvent (antifoaming organic liquid), and the like.

Japanese Patent Laid-Open No. 2002-338872 Japanese Patent Laid-Open No. 2006-070132

An object of this indication is to provide the coating composition which is hard to fall off from a base material, and provides the coating film with a small compression set, and the coating article provided with such a coating film.

The present disclosure includes a fluororubber, a polyol-based vulcanizing agent, an amino group-containing metal compound, and an organic solvent,

It relates to a fluororubber coating composition comprising 0.1 to 4.99 parts by mass of the polyol-based vulcanizing agent and the amino group-containing metal compound in total with respect to 100 parts by mass of the fluororubber.

It is preferable that the mass ratio of the polyol-based vulcanizing agent to the amino group-containing metal compound is 1.0:0.1 to 1.0:1.2.

It is preferable that the metal of the said amino group containing metal compound is at least 1 sort(s) selected from the group which consists of Si, Al, Ti, and Zr.

It is preferable that 0.1-3 mass parts of said polyol-type vulcanizing agent and the said amino group containing metal compound are 0.1-2 mass parts with respect to 100 mass parts of said fluororubbers.

It is preferable that the said fluororubber coating composition further contains a stabilizer.

It is preferable that the said stabilizer is an ortho ester type compound.

It is preferable that the said fluororubber coating composition further contains a surface conditioning agent.

It is preferable that the said fluororubber coating composition further contains an antifoamer.

The present disclosure, a metal plate,

A coating film formed of the fluororubber coating composition provided on one or both surfaces of the metal plate

It also relates to a coated article, characterized in that it has a.

It is preferable that the said coating article is a fluororubber coat gasket material.

ADVANTAGE OF THE INVENTION According to this indication, it is hard to fall off from a base material, and the coating composition provided with the coating film with a small compression set, and the coating article provided with such a coating film can be provided.

Hereinafter, the present disclosure will be specifically described.

The present disclosure includes a fluororubber, a polyol-based vulcanizing agent, an amino group-containing metal compound and an organic solvent, and a total of 0.1 to 4.99 parts by mass of the polyol-based vulcanizing agent and the amino group-containing metal compound with respect to 100 parts by mass of the fluororubber. It relates to a fluororubber paint composition comprising:

Since the fluororubber coating composition of this indication contains the said component, it is hard to fall off from a base material (a coating film is hard to deteriorate), and can provide a coating film with a small compression set. Therefore, when the said coating composition is applied to a sealing material, the outstanding sealing property is obtained.

The coating composition of the present disclosure is also excellent in coating stability.

Examples of the fluororubber include vinylidene fluoride [VdF] fluororubber, tetrafluoroethylene [TFE]/propylene [Pr] fluororubber, TFE/Pr/VdF fluororubber, ethylene [Et]/hexafluoropropylene and [HFP]-based fluororubber, Et/HFP/VdF-based fluororubber, Et/HFP/TFE-based fluororubber, fluorosilicone-based fluororubber, and fluorophosphazene-based fluororubber. Among them, VdF-based fluororubber is preferable.

The said fluororubber can use 1 type or 2 or more types.

Examples of the VdF-based fluororubber include VdF/HFP copolymer, VdF/TFE/HFP copolymer, VdF/chlorotrifluoroethylene [CTFE] copolymer, VdF/CTFE/TFE copolymer, VdF/perfluoro(alkylvinyl ether)[PAVE] copolymer, VdF/TFE/PAVE copolymer, VdF/HFP/PAVE copolymer, VdF/HFP/TFE/PAVE copolymer, VdF/TFE/Pr copolymer, VdF/Et/HFP copolymer, The copolymer etc. of the fluorine-containing monomer represented by VdF/formula (1) are mentioned.

Equation (1):

(wherein Rf is a linear or branched fluoroalkyl group having 1 to 12 carbon atoms)

As the polyol-based vulcanizing agent, a vulcanizing agent commonly used for polyol-vulcanized fluororubber can be used. As said polyol-type vulcanizing agent, it is a compound which has at least two hydroxyl groups, especially phenolic hydroxyl group in a molecule|numerator, and what has vulcanization performance is mentioned, This compound may be a high molecular compound.

Examples of the polyol-based vulcanizing agent include, among others, phenol derivatives such as bisphenol A, bisphenol AF, and hydroquinone, and salts thereof; polyhydroxy compounds having two or more enol-type hydroxyl groups in the molecule, such as phenol resins, and salts thereof; The compound represented by Formula: R _f ¹ (CH ₂ OH) ₂ (R _f ¹ represents a perfluoroalkyl polyether group), etc. are preferable.

As the polyol-based vulcanizing agent, in addition to the above, any commercially available polyol-based vulcanizing agent for fluororubber can be used.

The polyol-based vulcanizing agent may be used alone or in combination of two or more.

It is preferable to use 0.1-3 mass parts of said polyol-type vulcanizing agent with respect to 100 mass parts of said fluororubbers. A more preferable lower limit is 0.5 mass parts, and a more preferable upper limit is 2.5 mass parts.

In the coating composition of the present disclosure, in order to accelerate vulcanization, a vulcanization auxiliary may be used. Examples of the vulcanization auxiliary include alkyl and aralkyl quaternary ammonium salts; quaternary ammonium salts such as quaternary 1,8-diaza-bicyclo[5.4.0]-7-undecenium salt; tertiary amines; A quaternary phosphonium salt etc. are mentioned.

The usage-amount in the case of using the said vulcanization auxiliary|assistant is 0-10 mass parts with respect to 100 mass parts of said fluororubbers, for example. A preferable lower limit is 0.1 mass part, a more preferable minimum is 0.3 mass part, and a preferable upper limit is 5 mass parts.

The amino group-containing metal compound is preferably an amino group-containing metal compound containing at least one metal selected from the group consisting of Si, Al, Ti and Zr.

Preferred examples of the amino group-containing metal compound include an amino group-containing silane coupling agent, an amino group-containing aluminum coupling agent, an amino group-containing titanium coupling agent, and an amino group-containing zirconium coupling agent.

Preferred amino group-containing silane coupling agents include γ-aminopropyltriethoxysilane, N-β-aminoethyl-γ-aminopropyltrimethoxysilane, N-(trimethoxysilylpropyl)ethylenediamine, N-β-amino ethyl-γ-aminopropylmethyldimethoxysilane, γ-ureidepropyltriethoxysilane, β-aminoethyl-β-aminoethyl-γ-aminopropyltrimethoxysilane, and the like.

One type may be used for the said amino group containing metal compound, and may use 2 or more types together.

It is preferable to use 0.1-2 mass parts of said amino group containing metal compounds with respect to 100 mass parts of said fluororubbers. A more preferable lower limit is 0.5 mass parts, and a more preferable upper limit is 1.5 mass parts.

The coating composition of the present disclosure contains 0.1 to 4.99 parts by mass of the polyol-based vulcanizing agent and the amino group-containing metal compound in total with respect to 100 parts by mass of the fluororubber. When the total amount of the polyol-based vulcanizing agent and the amino group-containing metal compound is within the above range, a coating film with less permanent compression set and less easily missing from the substrate can be obtained. Moreover, it is excellent in paint stability.

The total amount of the polyol-based vulcanizing agent and the amino group-containing metal compound is preferably 1 part by mass or more, more preferably 2 parts by mass or more, still more preferably 2.2 parts by mass or more with respect to 100 parts by mass of the fluororubber. Moreover, it is preferable that it is 4.5 mass parts or less, and it is more preferable that it is 4 mass parts or less.

The mass ratio of the polyol-based vulcanizing agent to the amino group-containing metal compound (polyol-based vulcanizing agent:amino group-containing metal compound) is preferably 1.0:0.1 to 1.0:1.2. When the said mass ratio exists in the said range, it is hard to miss further from a base material, and the coating film with a further smaller compression set is obtained.

The mass ratio is more preferably 1.0:0.2 to 1.0:1.0, and still more preferably 1.0:0.5 to 1.0:0.9.

The coating composition of the present disclosure contains an organic solvent. The coating composition of the present disclosure may be a solvent-based coating material.

The organic solvent is not particularly limited, and for example, ketones such as methyl ethyl ketone [MEK], methyl isobutyl ketone [MIBK], diisobutyl ketone [DIBK], diacetone alcohol, cyclohexanone, and isophorone , esters such as butyl acetate and isopentyl acetate, ethers such as diethylene glycol dimethyl ether, hydrocarbons such as toluene and xylene, amino acids such as N,N-dimethylacetamide and N-methyl-2-pyrrolidone Drew can be used. The coating composition of this indication may use only 1 type of the said organic solvent, and may use 2 or more types of organic solvents. The compounding quantity of the said organic solvent can be suitably adjusted according to the kind of fluororubber mix|blended with the said coating composition.

It is preferable that the coating composition of this indication further contains a stabilizer. Thereby, it becomes a thing further excellent in coating material stability.

Examples of the stabilizer include orthoformic acid ester, orthocarbonate ester, cyclic orthoester, lactone acetal, orthoformic acid trimethyl ester, orthoformic acid triethyl ester, orthoacetic acid trimethyl ester, orthoacetic acid triethyl ester, orthocarbonate trimethyl ester, orthocarbonate triethyl. orthoester-based compounds such as ester, tetramethyl orthocarbonate, and tetraethyl orthocarbonate; Organic acids, such as monocarboxylic acid (formic acid, acetic acid, propionic acid, etc.) and dicarboxylic acid (oxalic acid, malonic acid, succinic acid, etc.) are mentioned. Especially, an ortho ester type compound is preferable, and an ortho acetate type compound is more preferable.

The coating composition of this indication may use only 1 type of said stabilizer, and may use 2 or more types of stabilizers.

It is preferable to use 1-8 mass parts of said stabilizers with respect to 100 mass parts of said fluororubbers. A more preferable lower limit is 2 mass parts, and a more preferable upper limit is 6 mass parts.

It is preferable that the coating composition of this indication further contains a surface conditioning agent.

As said surface conditioning agent, a siloxane compound, an acrylic copolymer, a methacrylic copolymer, etc. can be illustrated. Especially, an acrylic copolymer is preferable.

It is preferable to use 0.01-1 mass part of said surface conditioning agent with respect to 100 mass parts of said fluororubbers. A more preferable lower limit is 0.02 mass part, and a more preferable upper limit is 0.5 mass part.

It is preferable that the coating composition of this indication further contains an antifoamer.

As said antifoaming agent, a silicone type antifoamer, a polymer type antifoamer, etc. can be illustrated. Especially, a polymer type antifoamer is preferable.

It is preferable to use 0.05-4 mass parts of said antifoamers with respect to 100 mass parts of said fluororubbers. A more preferable lower limit is 0.1 mass part, a more preferable upper limit is 3 mass parts, and a more preferable upper limit is 2 mass parts.

It is preferable that the coating composition of this indication contains both the said surface conditioning agent and the said antifoamer. Thereby, at least the addition amount of these components is excellent in the defoaming property can be implement|achieved. Moreover, the coating film excellent in interlayer adhesiveness (especially adhesiveness with an upper layer) can also be obtained.

It is preferable that it is 1/20 - 1/50, and, as for mass ratio (surface conditioning agent/antifoaming agent) of the said surface conditioning agent and the said antifoaming agent, it is more preferable that it is 1/30 - 1/40.

In the coating composition of the present disclosure, in addition to the above components, various additives such as fillers and colorants may be blended.

Examples of the filler include carbon black, white carbon, calcium carbonate, barium sulfate, talc, and calcium silicate.

As said coloring agent, an inorganic pigment, a complex oxide pigment, etc. can be illustrated.

A coating film can be formed by apply|coating the coating composition of this indication to a base material, and drying. The coating composition of this indication may be apply|coated directly to a base material, and you may apply|coat through other layers, such as a primer.

Coating of the said coating composition can be performed by well-known coating methods, such as brush coating, spray coating, immersion coating, flow coating, dispenser coating, and screen coating.

After the said application|coating and drying, you may harden|cure as needed. When providing another layer, the said hardening may be performed for every layer, and may be performed collectively with respect to a some layer. Moreover, you may perform the said hardening simultaneously with the said drying.

Conditions for drying and curing can be appropriately set according to the type of the coating composition of the present disclosure, and the like.

As a substrate capable of applying the coating composition of the present disclosure, a substrate including metal, concrete, plastic, stone, wood, paper, and the like can be used. Especially, the base material containing a metal is preferable.

Examples of the metal include iron; stainless steel; aluminum; copper; brass; titanium; The plated steel sheet etc. which gave zinc plating, aluminum plating, etc. are mentioned. Especially, stainless steel is preferable.

The present disclosure also relates to a coated article characterized by having a metal plate and a coating film formed from the fluororubber coating composition of the present disclosure provided on one or both surfaces of the metal plate.

Since the coating article of this indication has the coating film formed from the coating material composition of this indication, a coating film is hard to fall off from a base material (a coating film is hard to deteriorate), and a compression set is small. Therefore, when the said coating article is applied to a sealing material, the outstanding sealing property is acquired.

As said metal plate, the plate containing the metal illustrated as a base material which can apply|coat the coating composition of this indication can be used.

The coating film formed of the coating composition of the present disclosure is provided on one or both surfaces of the metal plate. The said coating film may be provided directly on the said metal plate, and may be provided via other layers, such as a primer layer.

It is preferable that the thickness of the said coating film is 5-50 micrometers, and it is more preferable that it is 10-30 micrometers.

You may further provide another layer on the said coating film.

The coating article of this indication can be manufactured, for example by apply|coating the coating composition of this indication on the said metal plate, and drying.

After apply|coating and drying the said coating composition, you may harden|cure as needed. When providing another layer, the said hardening may be performed for every layer, and may be performed collectively with respect to a some layer. Moreover, you may perform the said hardening simultaneously with the said drying.

Conditions for drying and curing can be appropriately set according to the type of the coating composition of the present disclosure, and the like.

The coating composition and the coating article of the present disclosure can be used in fields that are difficult to miss from the substrate and require a coating with a small compression set, for example, various sheets and belts; sealing materials such as O-rings, diaphragms, valve seals, gaskets for chemical plants, and engine gaskets; fluid transport members such as chemical-resistant tubes, fuel hoses and joints; It can be used for rolls for OA equipment, such as a copier, a printer, and a facsimile (for example, a fixing roll, a crimping|compression-bonding roll), a conveyance belt, etc., Especially, it can use suitably for a gasket. It is one of suitable aspects that the coating article of this indication is a fluororubber coat gasket material.

Example

Next, the present disclosure will be described in more detail with reference to Examples, but the present disclosure is not limited only to these Examples.

<Preparation of fluororubber coating composition>

Example 1

5 parts by mass of carbon black and 5 parts by mass of acidic acid with respect to 100 parts by mass of solid content of the elastomer containing a vinylidene fluoride/hexafluoropropylene copolymer (vinylidene fluoride: hexafluoropropylene = 78:22 in molar ratio) as a fluororubber A mass part was kneaded with an open roll, and it was set as the compound. This compound was mixed with the mixed solvent comprised from 240 mass parts of diisobutyl ketones as an organic solvent, and 70 mass parts of isophorones, and the compound solution was obtained.

On the other hand, 2 parts by mass of the polyol vulcanizing agent and 0.5 parts by mass of the vulcanization auxiliary were dissolved in 10 parts by mass of ethanol, and 2 parts by mass of an orthoacetic acid ester compound and 2 parts by mass of an organic acid were added thereto as stabilizers. This solution was mixed with the previously prepared compound solution with a disper, and 0.05 parts by mass of an acrylic copolymer as a surface conditioner, 1.8 parts by mass of a polymeric antifoam as an antifoaming agent, and 1.2 parts by mass of an amino group-containing metal compound were mixed to obtain a fluororubber coating composition. .

Examples 2 to 6

A fluororubber coating composition was obtained in the same manner as in Example 1 except that the compounding amount of the surface conditioning agent and the antifoaming agent (or the antifoaming organic liquid) was changed as shown in Table 2.

In addition, as said antifoaming organic liquid, the ^{isoparaffin type solvent whose surface tension is 0.026 N*m<-1>} or less was used.

Example 7

A fluororubber coating composition was obtained in the same manner as in Example 1 except that an orthoacetic acid ester-based compound was not blended as a stabilizer.

Examples 8 and 9

A fluororubber coating composition was obtained in the same manner as in Example 1 except that the compounding amount of the amino group-containing metal compound was changed as shown in Table 1.

Comparative Examples 1 and 2

A fluororubber coating composition was obtained in the same manner as in Example 1 except that the blending amounts of the polyol-based vulcanizing agent and the amino group-containing metal compound were changed as shown in Table 1.

Comparative Example 3

A fluororubber coating composition was obtained in the same manner as in Example 1 except that the blending amounts of the polyol-based vulcanizing agent and the amino group-containing metal compound were changed as shown in Table 1, and no orthoacetate-based compound was blended as a stabilizer.

Comparative Example 4

A fluororubber coating composition was obtained in the same manner as in Comparative Example 1 except that an orthoacetic acid ester-based compound was not blended as a stabilizer.

<Production of the film>

25 g of the above coating composition was put into a fluorine-coated business card size tray, spread out over the entire surface, and left at room temperature for 3 days. Then, after drying at 100 degreeC for 24 hours, it baked at 200 degreeC for 60 minutes. When the film was taken out after baking and the film thickness was measured, it was about 300 micrometers.

<Production of the painting plate (painting article)>

On the SUS301 plate which had been previously cleaned with acetone, the coating composition was applied with a 16 mil applicator. After preliminary drying, it was dried at 80 to 100°C for 30 minutes, and then calcined at 200°C for 30 minutes.

<Deterioration of coating film (missing)>

The coating plate was sandwiched without using a spacer in a jig for measuring compression set, and after holding at 200° C. for 5 hours, the presence or absence of omission at the end of the coating film was visually observed and evaluated. It was made into (circle) that there was no protrusion of a coating film, and there was no omission at all, and that there was no protrusion of a coating film was made into (triangle|delta), and the presence of omission of a coating film was made into x. A result is shown in Table 1.

<Sealing property (compression permanent deformation): according to JIS K6262-5>

The coating film was overlapped to have a thickness of about 10 mm, and the thickness was measured with a dial gauge. Next, the sample was placed in a furnace at a temperature of 175°C under 25% compression and pressure for 72 hours, and then it was taken out from the furnace, left to cool at room temperature for 30 minutes, and then the thickness was measured with a dial gauge, and calculated according to the following formula. A result is shown in Table 1.

Compression set (ratio)=100×(t ₀ -t ₁ )/(t ₀ -t ₂ )

only

t ₀ : thickness before compression (mm)

t ₁ : thickness after compression (mm)

t ₂ : thickness of spacer (mm)

A thing of 50 % or less of compression set was made into (circle), a thing of 51 % - 89 % made (triangle|delta), and a thing of 90 % or more made x.

<Foaming (Paintability)>

After the fluororubber coating composition was sufficiently stirred on the SUS301 plate washed with acetone in advance, it was applied by screen printing so that the film thickness of the fired coating film became 25 µm. In the first application, since there are many bubbles formed by the movement of air in the mesh of the screen into the coating film, the application is performed 5 times, and in each of the second and subsequent 4 times, a stopwatch is started immediately after the application is finished, The time until the bubble disappear|disappeared from a film|membrane was measured, and the average value of 4 times was made into the defoaming time. The screen printing machine used for application is a generally commercially available manual printing method, and a commercially available 70 mesh ring-shaped screen was used. A result is shown in Table 2.

<Adhesiveness between layers (target layer)>

A fluororubber paint (methyl ethyl ketone [MEK] solution of VdF/HFP copolymer) as a top coat layer on the coating film obtained above is dip-coated, dried at 100° C. for 30 minutes, and then fired at 200° C. for 30 minutes. Thus, a test piece was obtained.

Based on JIS K5400, peeling of the cellophane tape from the coating film surface of the said test piece was repeated 10 times, and the number of masses (in 100 sheets) of the coating film which remained without peeling was calculated|required.

A result is shown in Table 2.

<Paint stability (pot life, coating film properties after storage)>

After the fluororubber coating compositions obtained in Examples and Comparative Examples were stored at 25°C for the time shown in Table 3, the coating viscosity was measured using a B-type viscometer.

Using the fluororubber coating composition stored at 25°C for 24 hours, a coating plate was produced in the same manner as above, and the coating film physical properties (coating film deterioration, sealing properties) were evaluated.

A result is shown in Table 3.

Claims (10)

Fluorine rubber, a polyol-based vulcanizing agent, an amino group-containing metal compound, and an organic solvent,
A fluororubber coating composition comprising 0.1 to 4.99 parts by mass of the polyol-based vulcanizing agent and the amino group-containing metal compound in total with respect to 100 parts by mass of the fluororubber. The fluororubber coating composition according to claim 1, wherein the mass ratio of the polyol-based vulcanizing agent to the amino group-containing metal compound is 1.0:0.1 to 1.0:1.2. The fluororubber coating composition according to claim 1 or 2, wherein the metal of the amino group-containing metal compound is at least one selected from the group consisting of Si, Al, Ti and Zr. The fluororubber coating composition according to any one of claims 1 to 3, wherein the polyol-based vulcanizing agent is 0.1 to 3 parts by mass and the amino group-containing metal compound is 0.1 to 2 parts by mass based on 100 parts by mass of the fluororubber. . The fluororubber coating composition according to any one of claims 1 to 4, further comprising a stabilizer. The fluororubber coating composition according to claim 5, wherein the stabilizer is an orthoester-based compound. The fluororubber coating composition according to any one of claims 1 to 6, further comprising a surface conditioning agent. The fluororubber coating composition according to any one of claims 1 to 7, further comprising an antifoaming agent. metal plate,
A coating film formed from the fluororubber coating composition according to any one of claims 1 to 8, provided on one or both surfaces of the metal plate.
Painted article, characterized in that it has. The painted article of claim 9 , which is a fluororubber coat gasket material.