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
  • C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
  • C09D175/04—Polyurethanes
• • 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
  • C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
  • C09D175/04—Polyurethanes
  • C09D175/06—Polyurethanes from polyesters
• • 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
  • C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
  • C09D7/40—Additives

Definitions

• the present invention relates to a low temperature curable clear coating composition.
• the outer plate of the vehicle body should not have deterioration and rust of the coating film, and should have durability to maintain the gloss or color of the coating film. Therefore, in the coating process of a vehicle, after the electrodeposition coating of a vehicle that has been subjected to a pre-treatment process, a middle coating is applied to improve adhesion and smoothness, and a base coating is applied to a vehicle that has been moderately coated for aesthetic appearance of the vehicle. Thereafter, it is common to apply a clear coating film to protect the color of the base coating film, improve the appearance, and protect the base coating film from the outside.
• thermosetting coating composition of a resin containing amino groups and an amino resin is widely used.
• parts made of plastic materials such as bumpers and rearview mirrors may deform or distort when the components are cured under high temperature curing conditions, so they must be separated from the vehicle body and separately painted. There was a hassle.
• Patent Document 1 discloses a clear coating composition comprising two types of acrylic polyol resin, polyester polyol resin, reactive silicone additive and isocyanate curing agent.
• the conventional low-temperature curing type clear coating composition such as the clear coating composition of Patent Literature 1
• the present invention is to provide a clear coating composition capable of producing a coating film having excellent mechanical properties while being curable at a low temperature of 120°C or lower.
• the present invention provides a low temperature curable clear coating composition
• a low temperature curable clear coating composition comprising a silicone-modified polyester polyol resin, an acrylic polyol resin and an isocyanate resin.
• the clear coating composition according to the present invention can be cured at a low temperature of 120° C. or lower, thereby reducing the cost required during the painting process, and is economical.
• the color can prevent different problems.
• the coating film prepared from the clear coating composition is excellent in mechanical properties such as hardness, adhesion, water resistance, acid resistance, scratch resistance, and solvent resistance, and thus can be usefully used for coating the body.
• the low-temperature-curable clear coating composition according to the present invention includes a silicone-modified polyester polyol resin, an acrylic polyol resin, and an isocyanate resin.
• the silicone-modified polyester polyol resin serves to impart coating properties to the composition.
• the silicone-modified polyester polyol resin may include a first repeating unit derived from an organic polysiloxane, a second repeating unit derived from a polyfunctional alcohol, and a third repeating unit derived from a polyfunctional carboxylic acid.
• the silicone-modified polyester polyol resin may be composed of a first repeating unit derived from an organic polysiloxane, a second repeating unit derived from a polyfunctional alcohol, and a third repeating unit derived from a polyfunctional carboxylic acid. That is, the silicone-modified polyester polyol resin may be prepared by reacting an organic polysiloxane, a polyfunctional alcohol monomer, and a polyfunctional carboxylic acid monomer. As another example, the silicone-modified polyester polyol resin may be prepared by condensation reaction of an organic polysiloxane, a polyfunctional alcohol monomer, and a polyfunctional carboxylic acid monomer.
• the organic polysiloxane may include functional groups and non-functional organic groups.
• the organic polysiloxane may include at least one functional group selected from the group consisting of silanol and alkoxy groups, and may include at least one non-functional organic group selected from the group consisting of methyl, propyl and phenyl groups.
• the alkoxy group includes, for example, methoxy, ethoxy and butoxy groups.
• the organic polysiloxane may have a number average molecular weight of 100 to 5,000g/mol.
• the organic polysiloxane may have a number average molecular weight of 200 to 5,000 g/mol, 300 to 4,000 g/mol, or 500 to 3,000 g/mol.
• organic polysiloxane Commercially available products of the organic polysiloxane include Dow Corning's DC-3037, DC-3074, RSN-0217, RSN-0220, RSN-0233, RSN-0255 and RSN-6018, Wacker's SILRES series, SY300, IC836, REN168 , SY409, IC232, SY231, IC368, IC678, 601, 603, 604 and the like.
• the polyfunctional alcohol monomer is, for example, ethylene glycol, propylene glycol, trimethylolpropane, trimethylolethane, cyclohexanedimethanol, neopentyl glycol, 2-butyl-2-ethyl-1,3-propanediol, 1 From the group consisting of,6-hexanediol, diethylene glycol, dipropylene glycol, tripropylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, triethylolpropane, glycerin and pentaerythritol. It may be one or more selected.
• the polyfunctional carboxylic acid monomer is, for example, phthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride It may be one or more selected from the group consisting of hydride, succinic anhydride, isophthalic acid, azlaic acid, maleic anhydride and trimellitic anhydride.
• the silicone-modified polyester polyol resin may be prepared by reacting 100 parts by weight of an organic polysiloxane, 300 to 800 parts by weight of a polyfunctional alcohol monomer, and 300 to 600 parts by weight of a polyfunctional carboxylic acid monomer.
• the silicone-modified polyester polyol resin is 100 parts by weight of an organic polysiloxane, 400 to 700 parts by weight, or 500 to 650 parts by weight of a polyfunctional alcohol monomer and 350 to 550 parts by weight, or 400 to 500 parts by weight of polyfunctionality It can be prepared by reacting a carboxylic acid monomer.
• the silicone-modified polyester polyol resin is prepared using the monomers in the above content range, there is an effect of improving the appearance characteristics and scratch resistance of the coating film prepared from the coating composition containing the same.
• the silicone-modified polyester polyol resin has a hydroxyl value of 150 mgKOH/g to 350 mgKOH/g, an acid value of more than 0 mgKOH/g and 30 mgKOH/g or less, a number average molecular weight of 100 to 10,000 g/mol, and glass at -50°C to 30°C. It can have a transition temperature.
• the silicone-modified polyester polyol resin has a hydroxyl value of 150 mgKOH/g to 300 mgKOH/g, or 200 mgKOH/g to 300 mgKOH/g, an acid value of 1 mgKOH/g to 30 mgKOH/g, or an acid value of 1 mgKOH/g to 20 mgKOH/g, It may have a number average molecular weight of 100 to 5,000 g/mol, or 100 to 2,000 g/mol, and a glass transition temperature of -30°C to 30°C, or more than 0°C and 20°C or less.
• the acrylic polyol resin serves to impart paintability to the composition.
• the acrylic polyol resin may include a repeating unit derived from an ethylenically unsaturated monomer and a repeating unit derived from an acrylic monomer containing a hydroxyl group. That is, the acrylic polyol resin may be prepared by reacting an ethylenically unsaturated monomer and an acrylic monomer containing a hydroxyl group. For example, the acrylic polyol resin may be prepared by reacting an ethylenically unsaturated monomer, an acrylic monomer containing a hydroxyl group, and a radical polymerization initiator under a solvent.
• the acrylic polyol resin may be prepared by reacting an ethylenically unsaturated monomer, an acrylic monomer containing a hydroxyl group, a non-functional acrylic monomer, a radical polymerization initiator, and a molecular weight modifier under a solvent.
• the ethylenically unsaturated monomer may be at least one selected from the group consisting of styrene and derivatives thereof, butadiene, C 1-12 alkyl (meth)acrylic and C 1-12 alkyl (meth)acrylic acid esters.
• the acrylic monomer containing the hydroxyl group is hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, kaduraacrylate, kaduramethacrylate, capro Lactone acrylate, caprolactone methacrylate, 2,3-dihydroxypropylacrylic, 2,3-dihydroxypropylmethacrylate, polypropylene modified acrylate, polypropylene modified methacrylate, 4-hydroxymethyl It may be at least one selected from the group consisting of cyclohexyl-methylacrylate, 4-hydroxymethylcyclo-methylmethacrylate and ethylenically unsaturated beta-hydroxy ester.
• the ethylenically unsaturated beta-hydroxy ester may be prepared by reacting an ethylenically unsaturated acid monomer with an epoxy compound.
• an ethylenic unsaturated acid monomer monocarboxylic acid, such as (meth)acrylic acid, is mentioned, for example.
• the epoxy compound is not involved in radical polymerization, and examples thereof include glycidyl ether and glycidyl ester.
• the non-functional acrylic monomer may be at least one selected from the group consisting of alkyl (meth) acrylate, cycloalkyl (meth) acrylate, and bicycloalkyl (meth) acrylate.
• the non-functional acrylic monomer is methyl methacrylate, ethyl methacrylate, iso-butyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate, n-hexyl methacrylate, 2- Ethyl hexyl methacrylate, iso-carbonyl methacrylate, cyclohexyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, iso-butyl acrylate, n-butyl acrylate, tert-butyl acrylate, 2 It may be at least one selected from the group consisting of -ethylhexyl acrylate, n-
• the solvent is not particularly limited as long as it is a conventional solvent used in radical polymerization, and examples include aromatic hydrocarbon-based solvents such as toluene and xylene; Ketone solvents such as methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone, and ethyl propyl ketone; Ester solvents such as methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate and ethyl ethoxypropionate; And alcohol-based solvents such as n-butanol, propanol and 1-methoxy-2-propanol; and the like.
• aromatic hydrocarbon-based solvents such as toluene and xylene
• Ketone solvents such as methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone, and ethyl propyl ketone
• commercially available products of the aromatic hydrocarbon-based solvent include cocosol #100, cocosol #150, and the like.
• the radical polymerization initiator is not particularly limited as long as it is a conventional polymerization initiator used in radical polymerization.
• the molecular weight modifier is not particularly limited as long as it is a common one used in the production of acrylic polyols.
• mercaptans such as n-dodecyl mercaptan, n-decyl mercaptan, and t-dodecyl mercaptan; And alpha methyl styrene dimers; And the like.
• the acrylic polyol resin has a hydroxyl value of 80 mgKOH/g to 200 mgKOH/g, an acid value of more than 0 mgKOH/g and 30 mgKOH/g or less, a number average molecular weight of 1,000 to 10,000 g/mol, and a glass transition temperature of more than 0°C and 70°C or less.
• the acrylic polyol resin has a hydroxyl value of 100 mgKOH/g to 200 mgKOH/g, an acid value of 1 mgKOH/g to 25 mgKOH/g, or an acid value of 5 mgKOH/g to 15 mgKOH/g, 1,500 to 7,000 g/mol, or 2,000 to 5,000 g /mol, and may have a glass transition temperature of 10°C to 70°C, or 20°C to 60°C.
• the curability of the composition containing the same may be improved, and when the acid value is within the above range, the reactivity of the composition containing the same may be controlled to adjust the appearance characteristics of the coating film prepared therefrom.
• the number average molecular weight is within the above range, the appearance properties and physical properties of the prepared coating film are appropriate, and when the glass transition temperature is within the above range, the initial hardness of the prepared coating film may be improved.
• the acrylic polyol resin may be included in an amount of 10 to 40 parts by weight based on 10 to 40 parts by weight of the silicone-modified polyester polyol resin.
• the acrylic polyol resin may be included in an amount of 15 to 35 parts by weight, or 20 to 30 parts by weight based on 10 to 40 parts by weight of the silicone-modified polyester polyol resin.
• the isocyanate resin serves to form a coating film by crosslinking the components in the composition and curing the composition.
• the isocyanate resin is composed of an isocyanurate group, an uretdione group, a biuret group, a urethane group, an allophanate group, and an iminooxadiazinedione group. It may include one or more functional groups selected from the group. That is, the isocyanate resin is an isocyanurate group, an uretdione group, a biuret group, a urethane group, an allophanate group, and an iminooxadiazinedione It may be an isocyanate containing at least one functional group selected from the group consisting of groups.
• the isocyanate resin may be prepared from aliphatic or alicyclic isocyanates.
• the isocyanate resin may be an aliphatic isocyanate such as 1,6-hexamethylene diisocyanate; And 1-isocyanato-3-isocyanatomethyl-3,5,5-trimethyl-cyclohexane (isophorone diisocyanate, IPDI), bis-(4-isocyanatocyclohexyl)-methane, Alicyclic isocyanates such as 1-isocyanato-1-methyl-4(3)-isocyanatomethyl cyclohexane, 2,4-hexahydrotoluylene diisocyanate and 2,6-hexahydrotoluylene diisocyanate ; Can be prepared from.
• the isocyanate resin is 1,6-hexamethylene diisocyanate, 1-isocyanato-3-isocyanatomethyl-3,5,5-trimethyl-cyclohexane and bis-(4-isocy Anatocyclohexyl)-methane.
• the isocyanate resin may be included in an amount of 5 to 40 parts by weight based on 10 to 40 parts by weight of the silicone-modified polyester polyol resin.
• the isocyanate resin may be included in an amount of 10 to 30 parts by weight, or 15 to 25 parts by weight based on 10 to 40 parts by weight of the silicone-modified polyester polyol resin.
• the coating composition may further include an organic solvent.
• the organic solvent serves to improve the workability of the composition by adjusting the viscosity of the coating composition.
• the organic solvent may include one or more selected from the group consisting of aromatic, acetate-based, alcohol-based and propionate-based.
• the organic solvent is an aromatic solvent such as toluene and xylene; Acetate-based solvents such as 1-methoxy-2-propyl acetate, methyl acetate, ethyl acetate, n-propyl acetate and n-butyl acetate; alcohol-based solvents such as n-butanol, propanol and 1-methoxy-2-propanol; And propionate-based solvents such as ethyl ethoxy propionate.
• commercially available products of the aromatic solvent include cocosol #100, cocosol #150, and the like.
• the organic solvent may be included in an amount of 10 to 50 parts by weight based on 10 to 40 parts by weight of the silicone-modified polyester polyol resin.
• the organic solvent may be included in an amount of 20 to 40 parts by weight, or 23 to 35 parts by weight based on 10 to 40 parts by weight of the silicone-modified polyester polyol resin.
• the coating composition containing the same has an effect of having excellent workability during manufacturing and painting.
• the coating composition may further include at least one additive selected from the group consisting of a curing catalyst, a surface modifier, a light stabilizer, an ultraviolet absorber, an antifoaming agent and a leveling agent.
• the additive may be included in an amount of 0.5 to 20 parts by weight based on 100 parts by weight of the silicone-modified polyester polyol resin.
• the additive may be included in an amount of 0.8 to 15 parts by weight, or 1 to 10 parts by weight based on 100 parts by weight of the silicone-modified polyester polyol resin.
• the curing catalyst serves to improve the mechanical properties of the coating film prepared therefrom by preventing incomplete curing of the coating composition.
• the curing catalyst may be at least one selected from the group consisting of dibutyltin dilaurate, triethyl amine, diethylenetriamine, bismuth carboxylate and zirconium chelate.
• the surface adjuster serves to control the smoothness of the coating layer by adjusting the surface tension after application of the coating composition, and can be used without particular limitation, as long as it is a common one that can be used in the coating composition.
• the surface modifier may be a surfactant, for example, a silicone-based surfactant.
• the light stabilizer serves to improve weather resistance.
• the light stabilizer may be used without particular limitation as long as it is a conventional one that can be used in the coating composition, for example, hindered amine-based.
• the hindered amine light stabilizer is 2,4-bis[N-butyl-N-(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl) Amino]-6-(2-hydroxyethylamine)-1,3,5-triazine, bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate and the like. have.
• the ultraviolet absorber absorbs ultraviolet rays to prevent discoloration of the coating composition, and serves to prevent swelling, delamination, and gloss loss of the coating film prepared from the coating composition.
• the ultraviolet absorber may be used without particular limitation as long as it is a common one that can be used in the coating composition, and examples thereof include benzotriazole-based hydroxyphenyl benzotriazole.
• commercially available products of the ultraviolet absorber include Tinuvin 384 from BASF.
• the anti-foaming agent serves to suppress the generation of air bubbles generated during the preparation of the coating composition and to suppress or remove phenomena such as pinholes or popping caused during the formation of the coating film.
• the antifoaming agent may be used without particular limitation as long as it is a conventional one that can be used in the coating composition.
• commercial products of the antifoaming agent include BYK-011, BYK-015, BYK-072 from BYK, DF-21 from Air Product, agitan 281 from Munzing, and Foamster-324 from Sannovko.
• the leveling agent serves to suppress the occurrence of orange peel by imparting smoothness to the coating composition to improve the appearance characteristics of the coating film prepared therefrom.
• the leveling agent can be used without particular limitation as long as it is a conventional one that can be used in the coating composition.
• the clear coating composition may be a two-part coating composition comprising a main portion and a curing agent portion. Accordingly, the clear coating composition may be used after mixing the main part and the curing agent part before application.
• the main part may include a silicone-modified polyester polyol resin, an acrylic polyol resin, and an organic solvent
• the curing agent part may include an isocyanate resin and an organic solvent.
• the clear coating composition may have a solid content of 40% to 70% by weight.
• the clear coating composition may have a solids content of 41% to 65% by weight, and in another example 42% to 62% by weight.
• the solid content of the clear coating composition is within the above range, there is an advantage that the coating workability of the composition becomes appropriate.
• the clear coating composition can be cured at 60 °C to 120 °C.
• the clear coating composition may be cured at 70 °C to 110 °C, or 80 °C to 110 °C. Since the clear coating composition is curable within the temperature range, it is economical to reduce the cost required during the coating process, and it is economical to paint the vehicle body and material parts combined therewith, so that the color of the parts and the vehicle body after painting is possible. Different problems can be avoided. In addition, since it is possible to coat both the vehicle body and the parts in one coating process, it is possible to reduce process hassle and cost loss.
• the clear coating composition may have a viscosity of 10 to 40 seconds based on the number 4 pod cup.
• the clear coating composition may have a viscosity of 15 to 35 seconds, or 20 to 35 seconds based on the number 4 pod cup.
• the viscosity of the clear coating composition is less than 10 seconds, problems such as vertical surface flowing down may occur, and if it is more than 40 seconds, the viscosity of the composition is high and the appearance characteristics of the coating film produced therefrom are low or the load is applied to the painter. It may cause sprayer failure.
• the clear coating composition according to the present invention as described above can be cured at a low temperature of 120° C. or lower, thereby reducing the cost required during the painting process, and is economical. After that, it is possible to prevent a problem in which colors of parts and a vehicle body are different. In addition, since it is possible to coat both the vehicle body and the parts in one coating process, it is possible to reduce process hassle and cost loss. Furthermore, the coating film prepared from the clear coating composition is excellent in mechanical properties such as hardness, adhesion, water resistance, acid resistance, scratch resistance, and solvent resistance, and thus can be usefully used for coating the body.
• functional groups such as'acid value' and'hydroxyl value' of the resin can be measured by a method well known in the art, and for example, can represent a value measured by a titration method.
• the'number average molecular weight' of the resin may be measured by a method well known in the art, for example, it may represent a value measured by the method of GPC (gel permeation chromatograph).
• the'glass transition temperature' of the resin may be measured by a method well known in the art, for example, may indicate a value measured by a differential scanning calorimetry (DSC) method.
• DSC differential scanning calorimetry
• the obtained silicone-modified polyester polyol resin-1 had a number average molecular weight of 928 g/mol, a hydroxyl value of 250 mgKOH/g, an acid value of 10 mgKOH/g, a glass transition temperature of 10°C, a solids content of 70% by weight in the total weight, and a property of Gardner viscosity YZ. Had.
• Neopentyl glycol 130 parts by weight, trimethylolpropane 448 parts by weight, DC-3074 (manufactured by Dow Corning) 121 parts by weight, and hexahydrophthalic in a four-necked flask equipped with a thermometer, stirrer, condenser, filling column and separation tube 502 parts by weight of unhydride was added and the temperature was raised to 230° C. while removing condensed water under a nitrogen atmosphere. After that, when the acid value of the prepared resin reached 20 mgKOH/g, the filling column was removed and the reaction was continued. Thereafter, when the acid value of the prepared resin reached 7 mgKOH/g, the mixture was cooled to 130° C., and then diluted by adding 480 parts by weight of butyl acetate to prepare silicone-modified polyester polyol resin-2.
• the obtained silicone-modified polyester polyol resin-2 had a number average molecular weight of 1,150 g/mol, a hydroxyl value of 280 mgKOH/g, an acid value of 10 mgKOH/g, a glass transition temperature of 5° C., a solid content of 70% by weight, and a Gardner viscosity Z1. It has physical properties.
• the obtained silicone-modified polyester polyol resin-3 had a number average molecular weight of 1,018 g/mol, a hydroxyl value of 133.7 mgKOH/g, an acid value of 35 mgKOH/g, a glass transition temperature of -10°C, a solid content of 70% by weight, and a Gardner viscosity. It had the properties of YZ.
• the obtained polyester polyol resin had physical properties of a number average molecular weight of 1,400 g/mol, a hydroxyl value of 195 mgKOH/g, an acid value of 10 mgKOH/g, a glass transition temperature of -5°C, a solid content of 75% by weight, and a Gardner viscosity Z of total weight. .
• a 4-necked flask equipped with a thermometer, stirrer, condenser and heating equipment 155 parts by weight of Cocosol #100, 15 parts by weight of ethyl ethoxypropionate and 148 parts by weight of glycidyl ester (HEXION, CADURA E10P) were purchased. The temperature was raised to 150°C. Thereafter, when the temperature was stable to isothermal, the monomer mixture was added dropwise for 300 minutes, and then isothermal was maintained for 120 minutes.
• the monomer mixture was prepared by mixing 208 parts by weight of styrene, 125 parts by weight of hydroxyethyl methacrylate, 54 parts by weight of acrylic acid and 20 parts by weight of tertiary butyl peroxide.
• the obtained acrylic polyol resin had a physical content of 60% by weight, a Gardner viscosity Z, a hydroxyl value of 150mgKOH/g, an acid value of 10mgKOH/g, a glass transition temperature of 40°C, and a number average molecular weight of 2,030g/mol.
• -Isocyanate resin hardener: Aliphatic polyisocyanate (Desmodur N 3300 from Covestro)
• Silicone surfactant (BYK-331)
• Hindered amine light stabilizer (BAu's Tinuvin 123)
• each component was stirred and mixed at 1,500 rpm for 20 minutes with the composition as described in Tables 1 and 2 below.
• Example 1 Example 2
• Example 3 Example 4
• Example 5 Example 6
• Example 7 Silicone-modified polyester polyol resin-1 25 - 35 10 40 7
• Silicone-modified polyester polyol resin-2 - 25 - - - - - Silicone-modified polyester polyol resin-3 - - - - - - - Polyester polyol resin - - - - - - - Acrylic polyol resin 25 25 10 40 10 38
• Curing catalyst 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1
• Surface modifier 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2
• Example 8 Comparative Example 1 Comparative Example 2 Comparative Example 3 Silicone-modified polyester polyol resin-1 - - 44 - Silicone-modified polyester polyol resin-2 - - - - Silicone-modified polyester polyol resin-3 25 - Polyester polyol resin - 24 - - Acrylic polyol resin 25 25 - 58 Isocyanate resin 20 19 22 18 additive Curing catalyst 0.1 0.1 0.1 0.1 0.1 Surface adjuster 0.2 0.2 0.2 0.2 0.2 Light stabilizer 0.6 0.6 0.6 0.6 UV absorber 1.1 1.1 1.1 1.1 Organic solvent Cocosol #100 14 15 16 12 Cocosol #150 14 15 16 10 Total 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
• Test Example Measurement of physical properties of the coating film prepared from the coating composition
• a top coat (manufacturer: KCC, product name: WT3090) was applied to the specimen and dried to form a top coat of 15 ⁇ m thickness. Thereafter, the clear coating compositions of Examples and Comparative Examples were coated on the top coat and cured at 100° C. for 25 minutes to form a clear coat having a thickness of 40 ⁇ m.
• the physical properties of the specimens were measured in the following manner, and the results are shown in Table 3.
• the clear coating film uses a handgun spray (nozzle diameter: 1.5 mm, air pressure: constant within and around 4.5 kgf/cm 2 ), and horizontally 40 to 40 while maintaining a constant distance between the nozzle inlet and the specimen at 30 cm. It was painted while moving at a speed of 50 cm/sec.
• the hardness of the clear coating film was measured by the pencil hardness method. Specifically, 3B, 2B, B, HB, F, H, 2H and 3H were used to measure the maximum hardness without damaging the clear coating film (3B, 2B, B, HB, F, H, 2H) , 3H: thirteen ⁇ excellent).
• the Go method 100 squares having a width of 2 mm and a width of 2 mm were made with a knife on the surface of the clear coating film, and then the square was removed using a tape to measure adhesion.
• the measured adhesiveness is M-1 (very good) when 100 squares are 100% intact, M-2 (excellent) when 70% or more and less than 100%, M- when 50% or more and less than 70% 3 (typical), M-4 (bad) when 30% or more and less than 50%, M-5 (very bad) when less than 30%.
• the heat treatment was repeated for a total of 3 cycles in one cycle, which was allowed to stand at room temperature for 20 minutes after heat treatment at 150°C for 20 minutes.
• the specimen was immersed in a constant temperature water bath at 40° C. for 240 hours and left at room temperature for 1 hour, and then a peeling test was performed in the same manner as in the Go method of item (2), and the evaluation criteria were also applied.
• 0.2 ml of 0.1 N sulfuric acid was added dropwise to the surface of the coated film of the specimen, and then treated in an oven preheated to 40° C. or higher for 150 minutes. At this time, the appearance of etching, staining or swelling of the portion where sulfuric acid was dropped on the specimen was visually observed to determine the highest temperature at which the specimen was not damaged as the acid resistance temperature.
• the 20° gloss of the specimen was measured (initial gloss measurement), and the surface of the specimen was reciprocated 10 times using a wash resistance tester (manufactured by Amtec Kistler) to measure the 20° gloss. Subsequently, the initial gloss and the gloss after the surface treatment were calculated by using Equation 1 below.
• Gloss retention rate gloss after surface treatment / initial gloss ⁇ 100
• Example 1 Item Solid content in total weight Hardness Adhesion Water resistance Acid resistance Initial gloss Scratch resistance (gloss retention rate) Solvent resistance Example 1 52.6% by weight F M-1 M-1 45°C 89% 65% 10 minutes Example 2 52.4% by weight F M-1 M-1 43°C 89% 65% 10 minutes Example 3 56% by weight F M-1 M-1 44°C 92% 64% 10 minutes Example 4 51% by weight HB M-1 M-1 43°C 89% 63% 10 minutes Example 5 61% by weight HB M-1 M-1 43°C 89% 62% 10 minutes Example 6 42% by weight HB M-1 M-2 40°C 85% 60% 8 minutes Example 7 54% by weight HB M-1 M-2 41°C 84% 61% 7 minutes Example 8 45% by weight B M-2 M-2 38°C 84% 61% 8 minutes Comparative Example 1 38% by weight 2B M-2 M-3 38°C 84% 52% 6 minutes Comparative Example 2 52.7% by weight B M-5 M-2 36°C 85% 54% 5 minutes Comparative Example 3 39% by weight 3
• the coating films prepared from the clear coating compositions of Examples 1 to 8 were excellent in mechanical properties such as adhesion, water resistance, acid resistance, scratch resistance and solvent resistance.
• the coating film prepared from the clear coating composition of Comparative Example 1 containing a polyester polyol resin lacks water resistance and scratch resistance, and the coating film prepared from the clear coating composition of Comparative Example 2 containing no acrylic polyol resin adheres. Castle and scratch resistance were insufficient.
• the coating film prepared from the clear coating composition of Comparative Example 3 that does not contain a silicone-modified polyester polyol resin is adhesive. Mechanical properties such as water resistance and scratch resistance were insufficient.
• the clear coating composition according to the present invention can be cured at a low temperature of 120° C. or lower, thereby reducing the cost required during the coating process, and is economical. After that, it is possible to prevent a problem in which colors of parts and a vehicle body are different.
• the coating film prepared from the clear coating composition has excellent mechanical properties such as hardness, adhesion, water resistance, acid resistance, scratch resistance, and solvent resistance, and thus can be usefully used for coating the body.

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• 2018
  • 2018-11-30 KR KR1020180151992A patent/KR102225801B1/ko active IP Right Grant
• 2019
  • 2019-11-08 SG SG11202105558QA patent/SG11202105558QA/en unknown
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