WO2007138396A1 - Procédé de formation d'un film de revêtement multicouche et produit recouvert d'un revêtement formé par ce procédé - Google Patents

Procédé de formation d'un film de revêtement multicouche et produit recouvert d'un revêtement formé par ce procédé Download PDF

Info

Publication number
WO2007138396A1
WO2007138396A1 PCT/IB2007/001128 IB2007001128W WO2007138396A1 WO 2007138396 A1 WO2007138396 A1 WO 2007138396A1 IB 2007001128 W IB2007001128 W IB 2007001128W WO 2007138396 A1 WO2007138396 A1 WO 2007138396A1
Authority
WO
WIPO (PCT)
Prior art keywords
coating film
resin
powder coating
film forming
powder
Prior art date
Application number
PCT/IB2007/001128
Other languages
English (en)
Inventor
Takafumi Umehara
Atsushi Takahashi
Rijun Nabeshima
Original Assignee
Basf Coatings Japan Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Basf Coatings Japan Ltd. filed Critical Basf Coatings Japan Ltd.
Publication of WO2007138396A1 publication Critical patent/WO2007138396A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
    • C09D5/03—Powdery paints
    • C09D5/033—Powdery paints characterised by the additives
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
    • B05D7/50—Multilayers
    • B05D7/52—Two layers
    • B05D7/54—No clear coat specified
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D163/00—Coating compositions based on epoxy resins; Coating compositions based on derivatives of epoxy resins
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
    • C09D5/03—Powdery paints
    • C09D5/033—Powdery paints characterised by the additives
    • C09D5/038—Anticorrosion agents

Definitions

  • the present invention concerns a method for forming a multilayer coating film having outstanding long-term corrosion resistance and outstanding chipping resistance and flexibility. More specifically, the invention concerns a multilayer coating film forming method that allows the formation of a coated product having a film coating that is used to form films on automotive underbody components, and not only has outstanding long-term corrosion resistance, but also shows resistance to chipping resulting from rocks, etc. that bounce up while driving, and outstanding flexibility and adhesion with respect to deformation of automobile components.
  • epoxy resin powder coatings have been widely used to coat automotive components requiring long-term durability.
  • epoxy resin powder coatings containing zinc powder have been proposed as epoxy resin powder coating compositions for undercoating use showing improved long-term corrosion resistance (cf. Patent Documents 1, 2, and 3) .
  • Patent Documents 1, 2, and 3 epoxy resin powder coating compositions for undercoating use showing improved long-term corrosion resistance
  • a powder coating composition showing improved chipping resistance that blends in polyolefin powder has been proposed (cf. Patent Document 4) .
  • coated products in which this powder coating composition is applied show problems from the standpoint of long-term corrosion resistance of the coating film.
  • Multilayer coating film forming methods have also been proposed as methods in which epoxy resin powder coatings containing zinc are used as undercoatings or overcoatings for commonly used powder coatings (cf. Patent Documents 5, 6, 7) .
  • Patent Documents 5, 6, 7 the performance requirements involving long-term durability of automotive components subjected to repeated vibration and stress have not been met .
  • Patent Document 1 Japanese Unexamined Patent Application No. 2001-146567
  • Patent Document 2 Japanese Unexamined Patent Application No. 2004-99808
  • Patent Document 3 Japanese Unexamined Patent Application No. 2004-189907
  • Patent Document 4 Japanese Unexamined Patent Application No. 2004-292573
  • Patent Document 5 Japanese Unexamined Patent Application No. H10-113613
  • Patent Document 6 Japanese Unexamined Patent Application No. 2005-218998
  • Patent Document 7 Japanese Unexamined Patent Application No. 2005-218998
  • the purpose of the present invention is to provide a multilayer coating film forming method in order to obtain a coated material having a coating film showing outstanding long-term corrosion resistance as well as outstanding chipping resistance, flexibility, and adhesion.
  • the inventors of the present invention conducted thorough research in an effort to achieve the above purpose, discovering that when a film was formed as an undercoating using a powder coating containing zinc, and a heat-curable powder coating composed of a resin having crosslinkable functional groups, a curing agent capable of reacting with said crosslinkable functional groups, a fibrous filler, and heat-expandable resin particles was applied thereto, by means of this multilayer coating film forming method, a coating film was obtained showing outstanding long-term corrosion resistance, as well as outstanding chipping resistance and flexibility, thereby meeting long-term durability requirements for automotive components subjected to repeated vibration and deformation, thus arriving at the present invention. [0007]
  • the present invention provides a multilayer coating film forming method, characterized by comprising a method in which, with respect to a metal coated material that has a first layer coating film composed of a first powder coating made up of a resin composition containing zinc, a second layer coating film composed of a second powder coating is formed on said material, and characterized in that said second powder coating is a heat-curable powder coating composition composed of a resin containing crosslinkable functional groups that are solid at room temperature (A) , a curing agent capable of reacting with said crosslinkable functional groups (B) , a fibrous filler (C) , and heat- expandable resin particles (D) .
  • the present invention provides a multilayer coating film forming method, characterized in that the first powder coating contains 50-500 parts by mass of zinc with respect to 100 parts by mass of the resin component . It also provides a multilayer coating film forming method, characterized in that the resin component of the first powder coating is composed of an epoxy resin and a curing agent capable of reacting with its crosslinkable functional groups. Furthermore, it provides a multilayer coating film forming method, characterized in that the curing agent of the first powder coating is at least one substance selected" from among an amine, polyamine, dihydrazide, dicyandiamide, imidazole, phenol resin, carboxyl group- containing polyester resin, and a dibasic acid or acid anhydride . [0009]
  • the present invention also provides a multilayer coating film forming method, characterized in that the resin composition of the first powder coating contains 1- 50 parts by mass of an extender pigment that has been surface-treated using a silane coupling agent with respect to 100 parts by mass of the resin component.
  • the present invention also provides a multilayer coating film forming method, characterized in that the first and second powder coatings are applied by means of at least one method selected from the electrostatic powder coating method and the flow immersion coating method. It also provides a coated product, characterized by having a multilayer coating film obtained by the above multilayer coating film forming methods formed on it. Moreover, the present invention also provides a coated product, characterized in that the product is a helical spring for automotive use.
  • the multilayer coating film forming method of the present invention achieves the effect of being able to form a multilayer coating film having outstanding corrosion resistance as well as outstanding chipping resistance and flexibility. Moreover, using the multilayer coating film forming method of the present invention as a coating for automotive underbody components has the effect of preventing rust due to chipping and peeling caused by rocks that bounce up during driving in cold areas in which snow melting agents such as rock salt are used, thus making it possible to protect the lower components of the automobile body over a long period of time.
  • the first powder coating is a powder material that forms a film containing zinc, and it is applied to the metal coated product before the second powder coating.
  • the resin composition contains zinc as its essential component, and an extender pigment should also preferably be added as a coupling agent.
  • an extender pigment should also preferably be added as a coupling agent.
  • coloring pigments, stabilizers, matting agents, defoaming agents, leveling agents, thixotropic agents, ultraviolet absorbers, surface control agents, curing accelerators, dispersants, viscosity control agents, waxes, etc. in order to obtain an optimum heat-curable powder coating.
  • the resin used in the resin composition contains crosslinkable functional groups that are solid at room temperature, and it is therefore in a solid state at room temperature (25 0 C) .
  • its softening point should be 160 0 C, with a softening point of 150 0 C being even more preferable.
  • the lower limit is ordinarily 60 °C.
  • a basic resin such as epoxy resin containing glycidyl groups, acrylic resin, or polyester resin containing hydroxyl groups in combination with a curing agent such as an amine, acid, or block isocyanate capable of reacting with said functional groups, with powder coatings containing epoxy resin as a basic resin being optimum examples.
  • this epoxy resin examples include aliphatic epoxy resins such as bisphenol A epoxy resin, bisphenol F epoxy resin, phenol novolac or cresol novolac epoxy resin, cyclic epoxy resin, hydrogenated bisphenol A or AD epoxy resin, propylene glycol diglycidyl ether, pentaerythritol polyglucidyl ether, epoxy resins obtained from aliphatic or aromatic carboxylic acids and epichlorohydrin, epoxy resins obtained from aliphatic or aromatic amines and epichlorohydrin, heterocyclic epoxy resins, spiro ring- containing epoxy resins, and epoxy modified resins.
  • aliphatic epoxy resins such as bisphenol A epoxy resin, bisphenol F epoxy resin, phenol novolac or cresol novolac epoxy resin, cyclic epoxy resin, hydrogenated bisphenol A or AD epoxy resin, propylene glycol diglycidyl ether, pentaerythritol polyglucidyl ether, epoxy resins obtained from aliphatic or aromatic carboxylic
  • examples of said epoxy resin curing agent include amines, polyamide, dycyandiamide, hydrazide, imidazole, phenol, carboxyl group-containing polyester resin, amide imide, dibasic acids, and anhydrides, with dihydride adipate, dicyandiamide, phenol resin, carboxyl group-containing polyester resin, and dibasic acids being preferred.
  • carboxyl group-containing polyester resin there are no particular restrictions on the carboxyl group-containing polyester resin, with specific examples including a polyester resin containing 2 or more carboxylic acid groups per molecule, and examples include an acid constituent having as its main component a polyvalent carboxylic acid and an alcohol constituent having as its main component a polyhydric alcohol as raw materials used in condensation polymerization by a common method. [0015]
  • aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, and their anhydrides, 2 , 6-naphthalene dicarboxylic acid, and 2 , 7-naphthalene dicarboxylic acid and their anhydrides, saturated aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, alicyclic dicarboxylic acids such as 1,4-dichlorohexane dicarboxylic acid and their anhydrides, lactones such as ⁇ -butyrolactone and ⁇ -caprolactone, aromatic oxymonocarboxylic acids such as p-hydroxyethoxy benzoic acid and hydroxycarboxylic acids corresponding thereto.
  • the acidic component may be used either individually or in combinations of 2 or more .
  • aliphatic glycols having a side chain such as ethylene glycol, 1,3 -propane diol, 1,4 -butane diol, 1,5-pentane diol, 1,5-hexane diol, diethylene glycol, triethylene glycol, 1, 4-cyclohexane diol, 1, 4-cyclohexane dimethanol, bisphenol A-alkylene oxide adducts, bisphenol S-alkylene oxide adducts, 1,2-propane diol, neopentyl glycol, 1,2- butane diol, 1,3 -butane diol, 1,2-pentane diol, 2,3- pentane diol, 1,4-pentane diol, 1,4-hexane diol, 2,5- hexane diol, 3 -methyl-1, 5-pentane diol, 1,2-dodecane di
  • the number-average molecular weight of the aforementioned carboxyl group containing polyester resin should be 1500-6000, with a figure of 2000-5000 being even more preferable. If the aforementioned number- average molecular weight is less than 1500, the performance of the coating film obtained will decrease, and on the other hand, if it exceeds 6000, the smoothness of the coating film obtained will be decreased. [0018]
  • the glass transition temperature (Tg) of the aforementioned carboxyl group-containing polyester resin should be 35- 100 0 C, and preferably 50-70°C.
  • the glass transition temperature of the present invention may be determined by using a differential scanning calorimeter (DSC) .
  • DSC differential scanning calorimeter
  • the curing agent contained in the first powder coating may be used individually or in combinations of 2 or more.
  • the ratio of the curing agent used should be 0.5-1.5 eq, based on equivalents of the functional groups in the curing agent, per 1 eq of the functional groups in the resin containing crosslinkable functional groups that are solid at room temperature, with an amount of 0.7-1.2 eq being preferred.
  • the average particle diameter of the zinc powder used in the first powder coating is 1-20 ⁇ m, and preferably 3-10 ⁇ m.
  • the average particle diameter of the zinc powder can be measured using a microtrack particle size distribution indicator.
  • the zinc content should be 50-500 parts by mass, and preferably 100-300 parts by mass, with respect to 100 parts by mass of the resin composition.
  • extender pigments examples include talc, alumina powder, mica powder, metal silicate, molten silica, silicon dioxide, feldspar, wet silica, dry silica, barium sulfate powder, diatomaceous earth, titanate salt, quartz, and potassium carbonate.
  • Particularly preferred extender pigments are metal silicate, wet type silica, dry type silica, and calcium carbonate.
  • silane coupling agents include titanate coupling agents and aluminate coupling agents.
  • the amount of the coupling agent used should be 0.1- 10 parts by mass, and preferably 0.5-5 parts by mass, with respect to 100 parts by mass of the extender pigment .
  • the extender pigment should be surface-treated according to a method known in the art.
  • the amount of the extender pigment used here should be 1-50 parts by mass of the extender pigment subjected to surface treatment with a silane coupling agent with respect to 100 parts by mass of the resin composition, with an amount of 10-40 parts by mass being particularly preferred.
  • coloring pigments include titanium dioxide, carbon black, graphite, iron oxide, lead oxide, chrome yellow, phthalocyanine blue, phthalocyanine green, quinacridone, perilene, aluminum powder, alumina powder, bronze powder, copper powder, tin powder, mica, and natural and synthetic mica.
  • the second powder coating is a heat-curable powder coating composition containing a resin having crosslinkable functional groups, a curing agent that reacts with these groups, a fibrous filler, and heat- expandable resin particles.
  • an optimum heat-curable powder coating can be obtained by including extender pigments, coloring pigments, stabilizers, matting agents, defoaming agents, leveling agents, thixotropic agents, ultraviolet absorbers, surface control agents, curing accelerators, dispersants, viscosity control agents, waxes, etc. in order to obtain an optimum heat-curable powder coating.
  • the resin (A) containing crosslinkable functional groups that are solid at room temperature used in the heat-curable powder coating composition of the second powder coating is in a solid state at room temperature
  • the softening point (25°C) .
  • it has a softening point of 160 0 C or below, with a point of 150° C or below being particularly preferred.
  • the lower limit is 60 °C. If the softening point exceeds 160 °C, the external appearance of the film will be impaired, and if the softening point is less than
  • this epoxy resin examples include aliphatic epoxy resins such as bisphenol A epoxy resin, bisphenol F epoxy resin, phenol novolac or cresol novolac epoxy resin, cyclic epoxy resin, hydrogenated bisphenol A or AD epoxy resin, propylene glycol diglycidyl ether, pentaerythritol polyglucidyl ether, epoxy resins obtained from aliphatic or aromatic carboxylic acids and epichlorohydrin, epoxy resins obtained from aliphatic or aromatic amines and epichlorohydrin, heterocyclic epoxy resins, spiro ring- containing epoxy resins, and epoxy modified resins.
  • aliphatic epoxy resins such as bisphenol A epoxy resin, bisphenol F epoxy resin, phenol novolac or cresol novolac epoxy resin, cyclic epoxy resin, hydrogenated bisphenol A or AD epoxy resin, propylene glycol diglycidyl ether, pentaerythritol polyglucidyl ether, epoxy resins obtained from aliphatic or aromatic carboxylic
  • the epoxy resin As needed, one may blend in liquid epoxy resins with the epoxy resin in a range such that the composition obtained will not undergo blocking during storage.
  • the epoxy equivalent of said epoxy resin should be 150-3000 g/eq, and preferably 170-2500 g/eq, with a figure of 200- 2000 g/eq being particularly preferred.
  • the epoxy resin a polymer microparticle dispersion-type epoxy resin having a core-shell structure, in which polymer microparticles having a core- shell structure are dispersed in the epoxy resin, is preferred. By evenly dispersing polymer microparticles having a core-shell structure in the epoxy resin, one can further impart the properties of high adhesion, low internal stress, and durability to the heat-curable powder coating composition.
  • this contributes toward improving chipping resistance at low temperatures .
  • the above properties can be more easily achieved, as one obtains more uniform dispersibility than in cases where polymer microparticles having a core-shell structure are added as is to the powder coating composition during manufacturing thereof .
  • polymer microparticles having a core-shell structure As an example of polymer microparticles having a core-shell structure, one can mention polymer microparticles having a core-shell structure composed of a rubber core layer and a hardened shell layer.
  • the average particle diameter of the polymer particles having a core-shell structure should preferably be 0.1-1 ⁇ m.
  • An example of a rubber material composed of a core layer is a copolymer of glycidyl group-containing ethylenically unsaturated monomers and other ethylenically unsaturated monomers.
  • an example of hard substances having shell structures include a copolymer of a hydroxyl group containing ethylene unsaturated monomer and other ethylene unsaturated monomers and a copolymer composed of carboxylic group-containing ethylene unsaturated monomers and other ethylene unsaturated monomers.
  • the amount of the polymer particles having a core- shell structure in 100 parts by mass of a polymer microparticle dispersion-type epoxy resin having a core- shell structure should be 1-50 parts by mass, and preferably 5-40 parts by mass, with a content of 10-20 parts by mass being particularly preferred.
  • Examples of a commercial product of this type of polymer microparticle dispersion-type epoxy resin having a core-shell structure include Epotohto YR-628 and YR-693, manufactured by Tohto Kasei Co., Ltd., etc. [0028]
  • the content ratio of the polymer microparticles having a core-shell structure in the total amount of the epoxy resin should be 1-50 parts by mass with respect to 100 parts by mass of the total epoxy resin, and preferably 1.5-30 parts by mass, with an amount of 2-20 parts by mass being particularly preferred, and an amount of 3-20 parts by mass being even more preferred.
  • Examples of the curing agent (B) used in the heat- curable powder coating composition of the second powder coating include curing agents such as polyester resins containing amines, polyamide, dicyandiamide, hydrazide, imidazole, phenol, and carboxyl groups, amidoimides, dibasic acids, and anhydrides, with dihydrazide adipate, dicyandiamide, phenol resin, carboxyl group-containing polyester resin, and dihydrochloric acid, etc., being preferred, and dihydrazide adipate, dicyandiamide, and phenol resin are particularly preferred. [0029]
  • curing agents such as polyester resins containing amines, polyamide, dicyandiamide, hydrazide, imidazole, phenol, and carboxyl groups, amidoimides, dibasic acids, and anhydrides, with dihydrazide adipate, dicyandiamide, phenol resin, carboxyl group-containing polyester resin, and dihydr
  • carboxyl group-containing polyester resin there are no particular restrictions on the carboxyl group-containing polyester resin, with specific examples including a polyester resin having 2 or more carboxylic acid groups per molecule, such as resins obtained by condensation polymerization according to the usual method using an acid constituent having a polyvalent carboxylic acid as its main component and an alcohol constituent having a polyhydric alcohol as its main component as raw materials.
  • a polyester resin having 2 or more carboxylic acid groups per molecule such as resins obtained by condensation polymerization according to the usual method using an acid constituent having a polyvalent carboxylic acid as its main component and an alcohol constituent having a polyhydric alcohol as its main component as raw materials.
  • aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, and their anhydrides, 2, 6-naphthalene dicarboxylic acid, and 2 , 7-naphthalene dicarboxylic acid and their anhydrides, saturated aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, and dodecane dicarboxylic acid and their anhydrides, alicyclic dicarboxylic acids such as 1, 4-dichlorohexane dicarboxylic acid and their anhydrides, lactones such as ⁇ -butyrolactone and ⁇ -caprolactone, aromatic oxymonocarboxylic acids such as p-hydroxyethoxy benzoic acid and hydroxycarboxylic acids corresponding thereto.
  • the acidic component may be used either individually or in combinations of 2 or more.
  • aliphatic glycols having a side chain such as ethylene glycol, 1,3-propane diol, 1,4-butane diol, 1,5-pentane diol, 1,5-hexane diol, diethylene glycol, triethylene glycol, 1, 4-cyclohexane diol, 1,4-cyclohexane dimethanol, bisphenol A-alkylene oxide adducts, bisphenol S-alkylene oxide adducts, 1,2-propane diol, neopentyl glycol, 1,2- butane diol, 1,3 -butane diol, 1,2-pentane diol, 2,3- pentane diol, 1,4-pentane diol, 1,4-hexane diol, 2,5- hexane diol, 3 -methyl- 1, 5-pentane diol, 1,2-dodecane dio
  • the number-average molecular weight of the aforementioned carboxyl group-containing polyester resin should be 1500-6000. A number-average molecular weight of 2000-5000 is even more preferable. If the aforementioned number-average molecular weight is less than 1500, the performance of the coating film obtained will decrease, causing problems with storage stability of the powder coating. On the other hand, if the number-average molecular weight exceeds 6000, the smoothness of the coating film obtained will be decreased.
  • the glass transition temperature (Tg) of the aforementioned carboxyl group-containing polyester resin should be 35- 100 0 C, and preferably 50- 70 "C.
  • the glass transition temperature of the present invention may be determined by using a differential scanning calorimeter (DSC) .
  • the curing agent contained in the heat-curable powder coating composition of the second powder coating may be used individually or in combinations of 2 or more.
  • the amount of the curing agent used should be 0.5-1.5 eq of the functional groups of the curing agent per 1 eq of the functional groups of the resin containing the crosslinkable functional groups that are solid at room temperature of component (A), and preferably 0.7-1.2 eq.
  • the fibrous filler (C) used in the heat-curable powder coating composition of the second powder coating one may use a fibrous filler when the aspect ratio of 5- 500, and preferably 10-250, with a ratio of 10-100 being even more preferable.
  • the term "aspect ratio” used here refers to the ratio of average fiber length to average fiber diameter (D) of the fibrous filler (L/D) .
  • the average fiber diameter and average fiber length of the fibrous filler can be measured using an optical microscope equipped with a micrometer eyepiece, the average fiber diameter should be 1-20 ⁇ m, with a diameter of 3-15 ⁇ m being particularly preferred. The average fiber length should be 50-300 ⁇ m, with a length of 100-200 ⁇ m being particularly preferred.
  • the fibrous filler there are no particular limits on the fibrous filler, provided that it is composed of an insulator, with examples including inorganic fibrous fillers and organic fibrous fillers.
  • inorganic fibrous fillers include calcium metasilicate, potassium tita ⁇ ate, magnesium sulfate, sepiolite, zonolite, aluminum borate, rock wool, and glass fibers.
  • organic fibrous fillers include polyoxybenzoyl (PO30B) , polyoxynaphthoyl (PON) , polyacrylonitrile fibers, aramid fibers, etc.
  • the fibrous filler may be used individually or in combinations or 2 or more .
  • the content of the fibrous filler (C) should be within the range of 1-100 parts by mass with respect to a total of 100 parts by mass of the resin containing crosslinkable functional groups that are solid at room temperature (A) and the curing agent capable of reacting with said crosslinkable functional groups (B) . If the amount is less than 1 part by mass, the improvement in chipping resistance will not be sufficient. Moreover, if it exceeds 100 parts by mass, the external appearance of the film will be impaired, and its long-term corrosion resistance will decrease. It is particularly preferable to add an amount of 5-50 parts by mass of the fibrous filler.
  • an effective means is coupling treatment of the filler interface, particularly in the case of inorganic fibrous fillers.
  • coupling agents include silane coupling agents, titanate coupling agents, and aluminate coupling agents.
  • treatments such as plasma treatment are preferred.
  • the heat-expandable resin particles (D) used in the heat-curable powder coating composition of the second powder coating one can mention microspheres composed of a thermoplastic resin shell enclosing a liquefied gas, which are characterized by the fact that when they are heated, the gas pressure inside the shell increases, the thermoplastic resin shell softens and expands, and hollow spherical particles are formed.
  • the average particle diameter of the heat- expandable resin particles (D) should be 5-30 ⁇ m.
  • the volume of the heat-expandable resin particles (D) after expansion should preferably be increased by a factor of 30-150.
  • Examples of commercial heat-expandable resin particles (D) include Expancel 092DU40, Expancel 092DU80, and Expancel 009DU80, manufactured by Japan Fillite Co., Ltd., and M520 and M520D microspheres manufactured by Dainichiseika Color and Chemicals Mfg. Co., Ltd. [0038]
  • the heat-expandable resin particles (D) may be used individually or in combinations of 2 or more.
  • the content of the heat-expandable resin particles (D) should be within the range of 0.1-20 parts by mass with respect to a total of 100 parts by mass of the resin containing crosslinkable functional groups that are solid at room temperature (A) and the curing agent capable of reacting with said crosslinkable functional groups (B) .
  • a particularly preferable content of the heat-expandable resin particles (D) is 0.5-15 parts by mass. If the content of the heat-expandable resin particles (D) is less than 0.1 part by mass, the improvement in chipping resistance will be insufficient.
  • prefoamed organic hollow resin particles and inorganic hollow particles may be included in the heat-curable coating composition of the second powder coating.
  • the heat-curable powder coating composition of the second powder coating may also contain plasticizers, coloring pigments, thermal stabilizers, optical stabilizers, matting agents, defoaming agents, leveling agents, thixotropic agents, ultraviolet absorbers, surface control agents, curing accelerators, dispersants, viscosity control agents, antistatic agents, waxes, etc.
  • coloring pigments there are no particular restrictions on the aforementioned coloring pigments, with examples including titanium dioxide, carbon black, graphite, iron oxide, lead oxide, chrome yellow, phthalocyanine blue, phthalocyanine green, quinacridone , perilene, aluminum powder, alumina powder, bronze powder, copper powder, tin powder, mica, and natural and synthetic mica.
  • melt kneaders such as hot rollers or extruders
  • wet method which involves melt dispersion in a solvent, followed by removal of the solvent by vacuum distillation or thin film distillation and pulverization.
  • the heat-curable powder coating composition of the present invention may be obtained by any method commonly known in the art, such as the electrostatic coating method or the flow immersion method to obtain a coating film thickness on the surface of the coated object of 50- 800 ⁇ m, and preferably 100-400 ⁇ m, and by carrying out baking, ordinarily at a temperature of 140-180 0 C for a period of 5 minutes to 2 hours, one can obtain a sufficiently cured foamed film.
  • the first undercoating powder coatings P-I through P-14 obtained were applied in a film thickness of 50-200 ⁇ m to a soft steel plate with a thickness of 2.3 mm subjected to lead phosphite treatment by means of electrostatic coating with a charge of -80 KV, and after baking for 20 minutes at 160 0 C, this was taken as the first undercoating powder film.
  • the second overcoating powder coatings S-I through S-14 were applied in a film thickness of 200-400 ⁇ m by means of electrostatic application with a charge of -80 KV to the first undercoating powder film, and baking was carried out for 20 minutes at 160 0 C to obtain a multilayer coating film.
  • Tables 6-8 show evaluation results for the multilayer coating film compositions.
  • ⁇ Number of remaining pieces of coating film after tape peeling is 70-99/100.
  • x Number of remaining pieces of coating film after tape peeling is 69 or less/100.
  • a coated plate crosscut in advance was placed for 960 hours in a saltwater-spray testing unit under conditions of 35 °C and 5% NaCl, and after removal, the width of unilateral swelling from the crosscut surface and the width of unilateral peeling caused by cellophane tape were evaluated.
  • Width of unilateral swelling and peeling is 1 mm or less.
  • Width of unilateral swelling and peeling is 1-3 mm.
  • ⁇ Width of unilateral swelling and peeling is 3-5 mm.
  • x Width of unilateral swelling and peeling exceeds 5 mm.
  • Moisture resistance according to JIS K5600 7-2
  • a coated plate was placed for 960 hours in a moisture-resistant testing unit under conditions of 50 0 C and 95% RH, and the adhesion of the material to the film was evaluated based on the number of remaining pieces of coating film using cellophane tape.
  • ⁇ Peeling reaching the substrate, with peeling area greater than 3 mm 2 and less than 10 mm 2 .
  • x Peeling reaching the substrate, with peeling area exceeding 10 mm 2 .
  • Product name manufactured by DSM, carboxyl group-containing polyester resin, acid value 85 mg/KOH/g, number-average molecular weight 2200, glass transition temperature 71 0 C.
  • the amount of zinc powder blended in as an undercoating was 500 parts or more by mass with respect to a total of 100 parts by mass of the resin and the curing agent capable of reacting with its crosslinkable functional groups, and this was an example in which fibrous filler was not mixed in with the overcoating; although saltwater-spray resistance was favorable, impact resistance was poor, and in chipping resistance, major peeling was observed.
  • the amount of the moisture-resistant pigment surface treated with a silane coupling agent of the undercoating was 50 parts by mass or more with respect to a total of 100 parts by mass of the resin and the coupling agent capable of reacting with its crosslinkable functional groups, and this was a case in which heat-expandable resin particles were blended in with the overcoating, moisture resistance was poor, and in chipping resistance, major peeling was observed.
  • the amount of the moisture-resistant pigment surface treated with a silane coupling agent mixed into the undercoating was less than 1 part by mass with respect to a total of 100 parts by mass of the resin and the coupling agent capable of reacting with its crosslinkable functional groups, and this was a case in which no heat-expandable resin particles were mixed in with the overcoating, so adhesion and moisture resistance were poor, and insufficient chipping resistance was achieved.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Wood Science & Technology (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Paints Or Removers (AREA)

Abstract

L'objectif de l'invention est de fournir un procédé de formation d'un film de revêtement multicouche permettant d'obtenir une matière de revêtement présentant d'excellentes caractéristiques en termes de résistance à la corrosion à long terme, de résistance à l'écaillage, de flexibilité et d'adhérence. À cet effet, le procédé selon l'invention consiste à former, sur une matière pourvue d'un revêtement métallique présentant une première couche de film de revêtement composée d'un premier revêtement pulvérulent constitué d'une composition de résine contenant du zinc, une seconde couche de film de revêtement composée d'un second revêtement pulvérulent, ce second revêtement pulvérulent étant une composition de revêtement pulvérulent thermodurcissable composé d'une résine contenant des groupes fonctionnels réticulables qui sont solides à température ambiante (A), un agent de durcissement pouvant réagir avec ces groupes fonctionnels réticulables (B), une charge fibreuse (C) et des particules de résine thermo-expansibles (D).
PCT/IB2007/001128 2006-05-29 2007-04-26 Procédé de formation d'un film de revêtement multicouche et produit recouvert d'un revêtement formé par ce procédé WO2007138396A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2006-147927 2006-05-29
JP2006147927A JP2007313475A (ja) 2006-05-29 2006-05-29 複層塗膜形成方法およびその塗装物品

Publications (1)

Publication Number Publication Date
WO2007138396A1 true WO2007138396A1 (fr) 2007-12-06

Family

ID=38457770

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2007/001128 WO2007138396A1 (fr) 2006-05-29 2007-04-26 Procédé de formation d'un film de revêtement multicouche et produit recouvert d'un revêtement formé par ce procédé

Country Status (2)

Country Link
JP (1) JP2007313475A (fr)
WO (1) WO2007138396A1 (fr)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8574708B2 (en) 2007-10-31 2013-11-05 Akzo Nobel Coatings International B.V. Thin chip resistant powder topcoats for steel
US8647745B2 (en) 2008-01-25 2014-02-11 Akzo Nobel Coating International B.V. Powder coating compositions having a substantially non-zinc containing primer
EP2530129A4 (fr) * 2010-01-27 2015-07-01 Fujikura Kasei Kk Composition de revêtement de couche de base, film composite et son procédé de fabrication
EP3031872A1 (fr) * 2014-12-08 2016-06-15 Pulver Kimya San. ve Tic. A.S. Composition de revêtement en poudre expansible et procédé de revêtement par poudre
WO2017064286A1 (fr) * 2015-10-16 2017-04-20 ThyssenKrupp Federn und Stabilisatoren GmbH Ressort revêtu
CN107431016A (zh) * 2015-03-30 2017-12-01 三井化学株式会社 填埋平坦化膜的制造方法及电子器件的制造方法
US10011736B2 (en) 2009-07-29 2018-07-03 Akzo Nobel Coatings International B.V. Powder coating compositions capable of having a substantially non-zinc containing primer
US20190107165A1 (en) * 2016-03-25 2019-04-11 Chuo Hatsujo Kabushiki Kaisha Highly durable spring and method of coating the same
US10344178B2 (en) 2009-04-03 2019-07-09 Akzo Nobel Coatings International B.V. Powder corrosion and chip-resistant coating
US20200347261A1 (en) * 2017-12-29 2020-11-05 Sogefi Suspensions Vehicle suspension element provided with a coating, method for depositing said coating and coating composition for this method
US11065641B2 (en) 2016-02-10 2021-07-20 Nhk Spring Co., Ltd. Coil spring manufacturing method and coil spring manufacturing device
CN113614929A (zh) * 2019-02-13 2021-11-05 老虎涂料有限责任及两合公司 封装材料

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5492401B2 (ja) * 2008-11-20 2014-05-14 曙ブレーキ工業株式会社 粉体塗料および粉体塗装方法
JP2013119582A (ja) * 2011-12-07 2013-06-17 Shinto Paint Co Ltd 金属亜鉛含有の粉体塗料組成物
JP6405083B2 (ja) * 2012-08-10 2018-10-17 Ntn株式会社 金属製自動車部品の塗膜の形成方法
KR20150051106A (ko) * 2013-10-30 2015-05-11 아크조노벨코팅스인터내셔널비.브이. 분말 코팅 조성물
CN105907245B (zh) * 2016-05-26 2019-01-04 河北晨阳工贸集团有限公司 一种桥梁预埋件达克罗和封闭层复合防腐涂层
JP6675549B2 (ja) * 2018-01-23 2020-04-01 ナトコ株式会社 金属用粉体塗料組成物、金属用粉体塗料組成物により形成された塗膜、金属用粉体塗料組成物により形成された塗膜を備える金属材、および、塗膜を備える金属材を製造する方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11310735A (ja) * 1998-04-28 1999-11-09 Shinto Paint Co Ltd エポキシ樹脂防食塗料組成物
JP2005218998A (ja) * 2004-02-06 2005-08-18 Asahi Sunac Corp 粉体塗装方法及び粉体塗装装置
EP1571188A2 (fr) * 2004-02-17 2005-09-07 Kabushiki Kaisha Kobe Seiko Sho Plaque métallique recouverte de résine ayant une excellente formabilité, soudabilité et résistance à la corrosion, pièces utilisant la plaque métallique recouverte de résine et procédé de fabrication
CN1712473A (zh) * 2004-06-24 2005-12-28 徐州正菱涂装有限公司 环氧富锌重防腐粉末涂料及其制备方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11310735A (ja) * 1998-04-28 1999-11-09 Shinto Paint Co Ltd エポキシ樹脂防食塗料組成物
JP2005218998A (ja) * 2004-02-06 2005-08-18 Asahi Sunac Corp 粉体塗装方法及び粉体塗装装置
EP1571188A2 (fr) * 2004-02-17 2005-09-07 Kabushiki Kaisha Kobe Seiko Sho Plaque métallique recouverte de résine ayant une excellente formabilité, soudabilité et résistance à la corrosion, pièces utilisant la plaque métallique recouverte de résine et procédé de fabrication
CN1712473A (zh) * 2004-06-24 2005-12-28 徐州正菱涂装有限公司 环氧富锌重防腐粉末涂料及其制备方法

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
DATABASE CA [online] CHEMICAL ABSTRACTS SERVICE, COLUMBUS, OHIO, US; LU, DONGFANG ET AL: "Anticorrosive zinc-enriched epoxy powdery coating composition and its production", XP002449845, retrieved from STN Database accession no. 145:490796 *
DATABASE WPI Week 200004, Derwent World Patents Index; AN 2000-048040, XP002450224 *
DATABASE WPI Week 200555, Derwent World Patents Index; AN 2005-538293, XP002450225 *

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8574708B2 (en) 2007-10-31 2013-11-05 Akzo Nobel Coatings International B.V. Thin chip resistant powder topcoats for steel
US8647745B2 (en) 2008-01-25 2014-02-11 Akzo Nobel Coating International B.V. Powder coating compositions having a substantially non-zinc containing primer
US10344178B2 (en) 2009-04-03 2019-07-09 Akzo Nobel Coatings International B.V. Powder corrosion and chip-resistant coating
US10011736B2 (en) 2009-07-29 2018-07-03 Akzo Nobel Coatings International B.V. Powder coating compositions capable of having a substantially non-zinc containing primer
US10550283B2 (en) 2009-07-29 2020-02-04 Akzo Nobel Coating International B.V. Powder coating compositions capable of having a substantially non-zinc containing primer
EP2530129A4 (fr) * 2010-01-27 2015-07-01 Fujikura Kasei Kk Composition de revêtement de couche de base, film composite et son procédé de fabrication
US9249309B2 (en) 2010-01-27 2016-02-02 Fujikura Kasei Co., Ltd. Base coat coating composition, composite film, and method for producing same
EP3031872A1 (fr) * 2014-12-08 2016-06-15 Pulver Kimya San. ve Tic. A.S. Composition de revêtement en poudre expansible et procédé de revêtement par poudre
WO2016091876A1 (fr) * 2014-12-08 2016-06-16 Pulver Kimya San. Ve Tic. A.S. Composition de revêtement en poudre expansible et procédé d'application de revêtement en poudre
CN107431016A (zh) * 2015-03-30 2017-12-01 三井化学株式会社 填埋平坦化膜的制造方法及电子器件的制造方法
WO2017064284A1 (fr) * 2015-10-16 2017-04-20 ThyssenKrupp Federn und Stabilisatoren GmbH Ressort revêtu
US20190024745A1 (en) * 2015-10-16 2019-01-24 ThyssenKrupp Federn und Stabilisatoren GmbH Coated spring
WO2017064286A1 (fr) * 2015-10-16 2017-04-20 ThyssenKrupp Federn und Stabilisatoren GmbH Ressort revêtu
RU2730122C2 (ru) * 2015-10-16 2020-08-17 Тиссенкрупп Федерн Унд Штабилизаторен Гмбх Пружина с покрытием
US11390757B2 (en) 2015-10-16 2022-07-19 ThyssenKrupp Federn und Stabilisatoren GmbH Coated spring
US11065641B2 (en) 2016-02-10 2021-07-20 Nhk Spring Co., Ltd. Coil spring manufacturing method and coil spring manufacturing device
US20190107165A1 (en) * 2016-03-25 2019-04-11 Chuo Hatsujo Kabushiki Kaisha Highly durable spring and method of coating the same
US20200347261A1 (en) * 2017-12-29 2020-11-05 Sogefi Suspensions Vehicle suspension element provided with a coating, method for depositing said coating and coating composition for this method
CN113614929A (zh) * 2019-02-13 2021-11-05 老虎涂料有限责任及两合公司 封装材料

Also Published As

Publication number Publication date
JP2007313475A (ja) 2007-12-06

Similar Documents

Publication Publication Date Title
WO2007138396A1 (fr) Procédé de formation d'un film de revêtement multicouche et produit recouvert d'un revêtement formé par ce procédé
US20090270533A1 (en) Heat-curable powder coating composition
US6346292B1 (en) Corrosion- and chip-resistant coatings for high tensile steel
US8574708B2 (en) Thin chip resistant powder topcoats for steel
EP2240544B1 (fr) Compositions de revêtement en poudre ayant une amorce ne contenant pratiquement pas de zinc
EP2459657B1 (fr) Compositions de revêtement de poudre aptes à avoir un amorceur ne contenant sensiblement pas de zinc
EP3390544B1 (fr) Compositions de revêtement résistant aux chocs
EP1528090B1 (fr) Materiau de revetement en poudre de resine epoxydique
US6663968B2 (en) Corrosion-and chip-resistant coatings for high tensile steel
US20230115050A1 (en) Thermally conductive and electrically insulating powder coating compositions
KR102042203B1 (ko) 분체도료 조성물
EP3519507B1 (fr) Revêtement
JPH11256074A (ja) 耐チッピング性熱硬化型粉体塗料及びその塗膜形成方法
JP4234474B2 (ja) 粉体塗料組成物
JP4162769B2 (ja) 塗膜形成方法及び塗膜
JP3656203B2 (ja) 熱可塑性粉体塗料

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 07734445

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 07734445

Country of ref document: EP

Kind code of ref document: A1