JP5673288B2 - Elastic coating laminated structure including fluororesin coating - Google Patents

Description

  The present invention relates to an elastic coating laminated structure including a fluororesin coating.

  For example, on wall materials, roofs, and rooftops of houses and condominiums, cracks occur due to deterioration of the base material such as concrete and temperature changes, causing problems such as water leakage. It is common to form a flexible elastic coating. Similar problems also occur in the coating of metals, glass, ceramics, plastics, and the like, which are hard substrates with large thermal expansion and contraction.

  As such an elastic coating structure, for example, a primer layer and then a non-fluorinated elastic coating layer such as an acrylic rubber-based coating are formed on a hard substrate (Patent Document 1 and Patent Document 2). Furthermore, it is also known to top coat urethane-based paint as necessary.

JP 60-195163 A Japanese Patent No. 3161593

  Non-fluorine-based elastic coatings have the advantage that they have good followability with hard substrates and are less likely to cause cracks, but have the problem of poor weather resistance. Therefore, it is conceivable to overcoat a fluororesin paint with excellent weather resistance, but the known fluororesin coatings tend to have insufficient adhesion to other materials, and the necessary follow-up There is a problem that interface property cannot be achieved and interfacial peeling occurs.

  The present invention has been completed to solve such problems, and an object of the present invention is to provide an elastic coating laminated structure excellent in weather resistance, adhesion to an elastic coating laminate, and followability.

  The present invention comprises an elastic coating film laminate and a fluorine-containing resin coating layer formed on the elastic coating film laminate, and the fluorine-containing resin coating layer comprises a fluorine-containing polymer and an acrylic polymer. It is related with the elastic-coating laminated structure formed by the coating material containing the composite particle which is a composite particle with an acid value of 4-18 mgKOH / g.

  ADVANTAGE OF THE INVENTION According to this invention, the elastic coating-film laminated structure which has a fluorine-containing resin coating-film layer excellent in weather resistance, adhesiveness with an elastic coating-film laminated body, and followable | trackability can be provided.

  The elastic coating film laminate structure of the present invention comprises an elastic coating film laminate and a fluorine-containing resin coating layer formed on the elastic coating film laminate, and the fluorine-containing resin coating layer comprises a fluorine-containing film. A composite particle of a polymer and an acrylic polymer, which is formed by a coating material including composite particles having an acid value of 4 to 18 mg KOH / g.

  Hereinafter, each element will be described.

(Elastic coating laminate)
The elastic coating laminate is not particularly limited as long as an elastic coating layer is formed on a hard substrate.

  Hard substrates include concrete, slate, tile, siding board and other building interior and exterior walls, roofing materials, and materials used on the roof, as well as metal, glass, plastics, ceramics and other plate materials and articles. It can be illustrated.

  The elastic coating layer formed on the hard substrate may be a single layer using a conventionally known elastic coating, but a multilayered elastic coating further provided with a top coat layer if necessary via a primer layer. It may be a membrane layer.

  Examples of elastic paints include, but are not limited to, acrylic rubber paints, urethane paints, silicone paints, and the like.

  Examples of the primer include conventionally known primer paints such as a paint using an epoxy resin, a urethane resin, an acrylic resin, a silicone resin, or a polyester resin as a binder.

  In the present invention, since the fluorine-containing resin coating layer is provided on the elastic coating film laminate, the top coating is not necessarily required for the elastic coating film laminate. For example, the fluorine-containing resin coating is applied on the existing elastic coating film. When a film layer is provided, that is, when used for repair, a top coat is necessarily present. In that case, the existing top coat may be used as a primer layer or an adhesive layer for improving the adhesion between the existing elastic coating film and the fluororesin coating film layer.

  Examples of the top coat of the elastic coating layered product include an acrylic coating layer, a urethane coating layer, and a silicone coating layer.

Specific examples of the elastic coating film laminate include the following laminated structures, but are not limited thereto.
Elastic coating laminate 1
Hard base: Concrete Primer layer: Acrylic resin-based coating Elastic coating layer: Acrylic rubber-based elastic coating Top coat layer: Urethane-based coating layer Elastic coating laminate 2
Hard substrate: Mortar Primer layer: Acrylic resin-based coating Elastic coating layer: Acrylic rubber-based elastic coating Top coat layer: Silicone-based coating layer Elastic coating layer 3
Rigid base material: Ceramic industry side board Board primer layer: Acrylic resin paint film Elastic paint film layer: Urethane paint film Top coat layer: Silicone paint film layer

  The thickness of each coating film layer in the elastic coating film laminate is not particularly limited, and may be appropriately selected depending on the use and construction location.

(Fluorine-containing resin coating layer)
The fluorine-containing resin coating layer is formed of a paint containing composite particles of a fluorine-containing polymer and an acrylic polymer and having an acid value of 4 to 18 mg KOH / g.

  Composite particles of a fluoropolymer and an acrylic polymer can be produced by polymerizing an acrylic monomer in the presence of the fluoropolymer particles.

などのパーフルオロオレフィン；クロロトリフルオロエチレン（ＣＴＦＥ）、フッ化ビニル（ＶＦ）、フッ化ビニリデン（ＶＤＦ）、トリフルオロエチレン、トリフルオロプロピレン、ペンタフルオロプロピレン、テトラフルオロプロピレン、ヘキサフルオロイソブテンなどの非パーフルオロオレフィンがあげられ、これらの１種または２種以上が用いられる。ＰＡＶＥとしてはパーフルオロ（メチルビニルエーテル）（ＰＭＶＥ）、パーフルオロ（エチルビニルエーテル）（ＰＥＶＥ）、パーフルオロ（プロピルビニルエーテル）（ＰＰＶＥ）などがあげられる。 The fluorine-containing polymer only needs to contain at least one fluoroolefin unit. Examples of the fluoroolefin include tetrafluoroethylene (TFE), hexafluoropropylene (HFP), perfluoro (alkyl vinyl ether) (PAVE),

Perfluoroolefins such as: chlorotrifluoroethylene (CTFE), vinyl fluoride (VF), vinylidene fluoride (VDF), trifluoroethylene, trifluoropropylene, pentafluoropropylene, tetrafluoropropylene, hexafluoroisobutene, etc. Examples thereof include perfluoroolefins, and one or more of these are used. Examples of PAVE include perfluoro (methyl vinyl ether) (PMVE), perfluoro (ethyl vinyl ether) (PEVE), perfluoro (propyl vinyl ether) (PPVE), and the like.

Also, functional group-containing fluoroolefin monomers can be used. As the functional group-containing fluoroolefin, for example, formula (1):
CX ¹ ₂ = CX ^2- (Rf) _m -Y ¹ (1)
(Wherein Y ¹ is —OH, —COOH, —SO ₂ F, —SO ₃ M ² (M ² is a hydrogen atom, NH ₄ group or alkali metal), carboxylate, carboxyester group, epoxy group or cyano. A group; X ¹ and X ² are the same or different and both are hydrogen atoms or fluorine atoms; R _f is a divalent fluorine-containing alkylene group having 1 to 40 carbon atoms or a divalent containing an ether bond having 1 to 40 carbon atoms A fluorine-containing alkylene group; and m is 0 or 1).

などがあげられる。 As a specific example, for example

Etc.

  In addition, iodine-containing monomers such as perfluoro (6,6-dihydro-6-iodo-3-oxa-1-hexene) described in JP-B-5-63482 and JP-A-62-212734, Periodinated vinyl ethers such as perfluoro (5-iodo-3-oxa-1-pentene) can also be used.

  In the present invention, the fluoropolymer may be one or more of fluoroolefins, or a copolymer of non-fluorine monomers copolymerizable with fluoroolefin. Also good. Non-fluorine monomers include, for example, olefins such as ethylene, propylene and isobutylene; vinyl ethers such as ethyl vinyl ether, cyclohexyl vinyl ether and hydroxybutyl vinyl ether; alkenyls such as allyl alcohol and allyl ether; vinyl acetate and vinyl lactate. Vinyl esters; ethylenically unsaturated carboxylic acids such as succinic anhydride and crotonic acid.

  Among these, preferable fluorine-containing polymers include fluorine-containing copolymers containing VDF units from the viewpoint of good weather resistance. Specifically, VDF / TFE / CTFE copolymer, VDF / HFP copolymer, VDF / TFE / HFP copolymer, VDF / CTFE copolymer, VDF / TFE / PAVE copolymer, etc. are resistant to weathering. Is particularly preferable from the viewpoint of good.

  The production method of the fluoropolymer particles is not particularly limited, and can be performed by a conventionally known emulsion polymerization method.

  Acrylic polymer that forms composite particles with fluorine-containing polymer is a copolymer of unsaturated carboxylic acid that gives acid value to composite particles and acrylic monomer mixture containing (meth) acrylic acid ester monomer It is obtained by doing.

  Examples of unsaturated carboxylic acid monomers include acrylic acid (AA), methacrylic acid, vinyl acetic acid, crotonic acid, cinnamic acid, 3-allyloxypropionic acid, 3- (2-allyloxyethoxycarbonyl) propionic acid, Itaconic acid, itaconic acid monoester, maleic acid, maleic acid monoester, maleic anhydride, fumaric acid, fumaric acid monoester, vinyl phthalate, vinyl pyromellitic acid, undecylenic acid and the like. Among them, acrylic acid is preferable from the viewpoint of good adhesion and thickening.

  Specific examples of the (meth) acrylic acid ester monomers include (meth) acrylic acid alkyl esters having 1 to 10 carbon atoms, such as methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, and n-butyl. One or two of acrylate (BA), methyl methacrylate (MMA), n-propyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isopropyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, etc. More than one species can be exemplified. Of these, MMA, BA and the like are preferable from the viewpoint of good compatibility with the fluoropolymer.

  In addition, other copolymerizable radical polymerizable non-fluorinated monomers may be used in combination. Examples of other monomers include vinyl ether monomers, olefin monomers, hydrolyzable silyl group-containing vinyl monomers, vinyl ester monomers, and the like.

  Examples of vinyl ether monomers include alkyl vinyl ethers and hydroxyl group-containing vinyl ethers.

  Examples of the hydroxyl group-containing vinyl ether include 2-hydroxyethyl vinyl ether, 3-hydroxypropyl vinyl ether, 2-hydroxypropyl vinyl ether, 2-hydroxy-2-methylpropyl vinyl ether, 4-hydroxybutyl vinyl ether, 4-hydroxy-2-methylbutyl vinyl ether. , 5-hydroxypentyl vinyl ether, 6-hydroxyhexyl vinyl ether, 2-hydroxyethyl allyl ether, 4-hydroxybutyl allyl ether, glycerol monoallyl ether, and the like, which contribute to improving adhesion to the elastic coating laminate To do.

  Examples of the olefin monomer include ethylene, propylene, n-butene, isobutene, styrene, and the like, and properties such as improvement in flexibility can be imparted to the coating film.

  Examples of the hydrolyzable silyl group-containing vinyl-based monomer include γ-methacryloxypropyltrimethoxysilane, which contributes to improvement in adhesion to the elastic coating film laminate.

  Examples of vinyl ester monomers include vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl pivalate, vinyl caproate, vinyl versatate, vinyl laurate, vinyl stearate, vinyl cyclohexylcarboxylate, and benzoic acid. Carboxylic acid vinyl esters such as vinyl acid and vinyl para-t-butylbenzoate can be mentioned, and properties such as improvement in gloss and increase in glass transition temperature can be imparted to the coating film.

  Non-limiting preferred acrylic polymers include, for example, MMA / BA / AA (= 55 to 97/2 to 35/1 to 10 mol% ratio).

  A conventionally known method can be adopted as a method for combining the fluoropolymer particles and the acrylic polymer. For example, a method (so-called seed polymerization method) of emulsion polymerization of the acrylic monomer mixture in the presence of the fluoropolymer particles can be mentioned.

  The acid value of the composite particles used in the present invention is 4 to 18 mgKOH / g. When the acid value is less than 4 mgKOH / g, the adhesiveness with the elastic coating film laminate is inferior, and the desired follow-up property cannot be obtained. When the acid value exceeds 18 mgKOH / g, water resistance is deteriorated and storage stability is deteriorated, which is not preferable. The lower limit of the acid value is preferably 5 mgKOH / g from the viewpoint of further improving the crack resistance in the freeze-thaw test, and further 6 mgKOH / g from the viewpoint of particularly excellent adhesion to the elastic paint. Further, the preferable upper limit of the acid value is 15 mgKOH / g from the viewpoint of further improving the elasticity, and further 12 mgKOH / g from the viewpoint of particularly excellent water resistance.

  Various methods can be adopted as a method of adjusting the acid value of the composite particles within the range of the present invention. For example, (1) a method of adjusting the amount of unsaturated carboxylic acid units in the acrylic polymer, (2) a method of adjusting the ratio of the fluorinated polymer and the acrylic polymer in the composite particles, and (3) these methods Combination methods are available.

  By adjusting the mass ratio of the fluorinated polymer and the acrylic polymer in the composite particles, the acid value can be adjusted as described above, and the characteristics such as weather resistance, water resistance, and storage stability are adjusted. be able to. Increasing the proportion of the acrylic polymer may improve the gloss while decreasing the weather resistance. From this viewpoint, for example, the mass ratio of the fluorine-containing polymer and the acrylic polymer is preferably 70/30 to 30/70.

  The fluorine content of the composite particles is 15 to 45% by mass. When the content is within this range, the compatibility between the fluoropolymer and the acrylic polymer is good.

  The average particle size of the composite particles is preferably 250 nm or less, more preferably 50 to 250 nm, and particularly preferably 100 to 160 nm. When the average particle diameter is less than 50 nm, the viscosity of the aqueous dispersion increases, and there is a tendency that a high concentration aqueous dispersion cannot be obtained. When the average particle diameter exceeds 250 nm, the particles settle and solidify during storage of the aqueous dispersion. Furthermore, there is a tendency that the gloss does not appear when the coating film is prepared.

  The fluororesin coating material for forming the fluororesin coating film layer in the present invention may consist only of the composite particles as a binder resin, and other resins or additives as long as the followability is not substantially affected. May be contained in an appropriate amount.

  The fluorine-containing resin paint is preferably in the form of an aqueous paint from the viewpoint of paint stability.

  When preparing an aqueous coating composition containing a pigment, water, a pigment such as titanium oxide, an antifoaming agent, a pigment dispersing agent, a pH adjusting agent, etc. are previously added to the aqueous dispersion of composite particles using a pigment dispersing machine such as a sand mill. After stirring and mixing a predetermined amount of the dispersed pigment dispersion and a predetermined amount of the film-forming auxiliary, a predetermined amount of a thickener is added and mixed, and other necessary additives may be added as appropriate. When preparing an aqueous coating composition without adding a pigment, water, a film-forming auxiliary agent, an antifoaming agent, a thickener, a pH adjuster, etc., if necessary, in an aqueous dispersion of fluorine-containing seed polymer particles What is necessary is just to stir and mix by a well-known method, adding a required additive.

  Conventionally known methods and conditions can be adopted as a method for forming the fluorine-containing resin coating layer. For example, the coating film may be formed on the elastic coating film laminate by a coating method such as spray coating, roll coating, flow coating, roller, or brush painting, and then dried at 5 to 200 ° C. The film thickness is not particularly limited, but may be appropriately selected in the range of 5 to 100 μm from the viewpoint of cost and paintability.

  Next, the present invention will be described with reference to examples, but the present invention is not limited to such examples.

  The apparatus and measurement conditions used for property evaluation are as follows.

(Storage stability test)
200 g of the composite particles are placed in a 250 ml plastic bottle and left in a thermostatic layer set at 50 ° C. for 4 weeks. Thereafter, the state of the composite particles is visually confirmed to determine whether or not the particles are gelled.
Evaluation criteria are set as (circle) when it is not gelatinized and x when it is gelatinized.

(Heating / cooling repeated test)
The test coated plate is dried at 23 ° C. for 7 days, then left in air at −20 ° C. for 2 hours, and then immersed in water at 10 ° C. for 2 hours. After repeating this cycle 10 times, it is dried at 23 ° C. for 1 day, and the grade of primary adhesion (JIS K5600-8-5) and cracking (JIS K5600-8-4) is evaluated.

Evaluation criteria for primary adhesion Density is a grade of 0-5 (smaller is 0), size is a grade of S1-S5 (S1 is smaller), depth is a grade of a-b (a is more For example, 2 (S1) a.

Evaluation criteria for cracks Density is grade 0-5 (smaller is 0), size is grade S0-S5 (smaller S0), depth is grade a-c (a is shallower) For example, 2 (S1) b.

（式中、ｎは１０と１１の混合物）で示される化合物（２−１）の３８質量％水溶液０．７８９ｇ（化合物（２−１）の濃度６００ｐｐｍ／水）を仕込み、系内を窒素ガスで充分に置換後、減圧にした。続いて重合槽内を系内圧力が０．７５〜０．８０ＭＰａとなるようにＶＤＦ／ＴＦＥ／ＣＴＦＥ（＝７４／１４／１２モル％）混合単量体を圧入し、７０℃に昇温した。 Example 1
In a 2 L stainless steel autoclave, 500 g of ion exchange water, formula:

(Wherein n is a mixture of 10 and 11) is charged with 0.789 g of a 38 mass% aqueous solution of compound (2-1) (concentration of compound (2-1): 600 ppm / water), and the system is filled with nitrogen gas Then, the pressure was reduced. Subsequently, a VDF / TFE / CTFE (= 74/14/12 mol%) mixed monomer was injected into the polymerization tank so that the internal pressure became 0.75 to 0.80 MPa, and the temperature was raised to 70 ° C. .

  Next, a polymerization initiator solution in which 1.0 g (2000 ppm / water) of ammonium persulfate (APS) was dissolved in 4 mL of ion-exchanged water and 0.75 g (1500 ppm / water) of ethyl acetate were injected with nitrogen gas and stirred at 600 rpm. The reaction was started.

  When the internal pressure began to drop as the polymerization progressed, a VDF / TFE / CTFE (= 74/14/12 mol%) mixed monomer was supplied so that the internal pressure was maintained at 0.75 to 0.80 MPa. . Two hours and five minutes after the start of polymerization, unreacted monomers were released, and the autoclave was cooled to obtain a dispersion of a fluoropolymer (Ia) having a solid content concentration of 10.6% by mass.

  In order to ensure the stability of seed particles during seed polymerization, 1200 g of a fluoropolymer (Ia) dispersion is charged into a 2 L four-necked flask equipped with a stirring blade, a cooling tube and a thermometer. Surfactant (manufactured by Sanyo Kasei Co., Ltd., Eleminol JS-20) is 1% by mass with respect to the solid content of the fluoropolymer, and RMA-450M (manufactured by Nippon Emulsifier Co., Ltd.) is based on the solid content of the fluoropolymer. 3 mass%, RS-3000 (manufactured by Nippon Emulsifier Co., Ltd.) was added at 1 mass% with respect to the solid content of the fluoropolymer. Warming in a water bath with stirring, the temperature in the flask was raised to 75 ° C. Separately, 87.4 / 10 / 2.6 (molar ratio) of MMA, BA and AA mixed monomer and 1% aqueous solution of APS (amount corresponding to 0.158% by mass of the mixed monomer) A mixed emulsion was prepared, and the mixed emulsion was dropped into the flask over 2 hours to polymerize. 2.5 hours after the start of the polymerization, the temperature in the flask was raised to 80 ° C., kept for 2 hours, cooled, neutralized with ammonia water to adjust the pH to 7, filtered through a 300 mesh wire mesh, and blue An aqueous dispersion of white fluorine-acrylic composite particles (average particle size 200 nm) was produced. The acid value of the obtained composite particles was 6 mgKOH / g.

  Using the obtained aqueous dispersion of composite particles, a weather-resistant water-based paint composition for buildings (white paint composition) was prepared according to the following formulation.

(Prescription of white paint composition)
Aqueous dispersion of fluorine-acrylic composite particles 65.00 parts by weight Water 9.12 parts by weight Titanium oxide 31.39 parts by weight Pigment dispersant 2.35 parts by weight Antifreeze agent 1.79 parts by weight pH adjuster 0.04 Parts by weight defoaming agent 0.11 parts by weight thickener 1 0.38 parts by weight thickener 2 0.40 parts by weight film-forming aid 2.35 parts by weight

The components used are as follows.
Titanium oxide: Ishihara Sangyo Co., Ltd. Taipaek CR-97
Pigment dispersant: Sannopco Nop Cospers SN-5027 (trade name)
Antifreeze agent: Ethylene glycol pH adjuster: Ammonia water defoamer: FS Antifoam 013A (trade name) manufactured by Dow Corning
Thickener 1: Adecanol UH-420 (trade name) manufactured by Asahi Denka Kogyo Co., Ltd.
Thickener 2: Primal ASE-60 (trade name) manufactured by Rohm and Hearts Japan
Film-forming aid: Diethyl adipate

The obtained white paint composition was applied to a slate plate (previously coated with acrylic rubber paint (High Proof (trade name) manufactured by Nippon Special Paint Co., Ltd.) to 200 g / m ² and dried at room temperature for 1 day. 1) was applied with a brush at 150 g / m ² and dried at room temperature for 1 day to prepare a test coated plate.

  The obtained test coated plate was subjected to a storage stability test and a hot and cold repeated test. In addition, the results of the hot / cold repeated test and the storage stability were comprehensively judged, and a case where good results were obtained in any of the tests was evaluated as ◯. The results are shown in Table 1.

Examples 2-3 and Comparative Examples 1-2
Fluorine-acrylic composite particles were produced in the same manner as in Example 1 except that the acrylic polymer was changed to the monomer composition shown in Table 1, and each of the obtained fluorine-acrylic composite particles was used in the same manner as in Example 1 to obtain white. A coating composition was prepared.

  Using the obtained white paint composition, a test coated plate was produced in the same manner as in Example 1, and the obtained test coated plate was subjected to a storage stability test and a hot and cold repeated test. The results are shown in Table 1.

  From the results in Table 1, it can be seen that by adjusting the acid value of the composite particles, it is possible to obtain a coating film that has excellent adhesion to an elastic paint and is resistant to cracking.

Claims (4)

An elastic coating film laminate and a fluorine-containing resin coating layer formed on the elastic coating film laminate, the fluorine-containing resin coating layer being a composite particle of a fluorine-containing polymer and an acrylic polymer Ri Na is formed by paint containing composite particles having an acid number of 4~18mgKOH / g comprising at,
An elastic coating film laminated structure in which the elastic coating material forming the elastic coating film layer constituting the elastic coating film laminate is an acrylic rubber-based coating material. Fluorine-containing polymer constituting the double engagement grains child, vinylidene fluoride / tetrafluoroethylene / chlorotrifluoroethylene copolymer, vinylidene fluoride / hexafluoropropylene copolymer, vinylidene fluoride / tetrafluoroethylene / hexa hexafluoropropylene copolymer, elastic coating film laminated structure of claim 1 Symbol mounting a vinylidene fluoride / chlorotrifluoroethylene copolymer or a vinylidene fluoride / tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer. The acrylic polymer constituting the double engagement particles child, elastic coating film multilayer structure according to claim 1 or 2, wherein a copolymer of methyl methacrylate and butyl acrylate and acrylic acid. Elastic coating film layered structure according to any one of claims 1 to 3 acid value of the multi engagement particle element is 6~15mgKOH / g.