KR100947280B1 - Road marking aqueous coating composition - Google Patents

Abstract

Aqueous coating compositions for road marking are disclosed that are fast-dried and have improved yellowing.

The composition is selected from binder polymers, zinc phosphate and calcium zinc phosphate

At least one pigment.

Description

Aqueous coating composition for road marking {ROAD MARKING AQUEOUS COATING COMPOSITION}

The present invention relates to an aqueous coating composition for road use, and more particularly to an aqueous coating composition for road marking having quick drying properties and improved yellowing properties.

One of the many major features of common coatings, especially road markings and traffic paints, is the drying speed on a particular substrate surface after coating.

For example, the speed of drying paint is directly related to the time when paint is collapsed by road traffic while paint is applied to the road surface and subsequently dried. This trend called for shorter decay times due to traffic flows, and this demand required paints with shorter drying times. As used herein, the terms "coating" and "paint" are used interchangeably and are a generic concept including traffic paint and road marking.

In addition, the terms "traffic paint" and "road marking" are used interchangeably.

Solvent-based quick-drying coatings are organic polymer resins (hereinafter referred to as 'binders') that are dissolved, suspended or dispersed in a relatively low boiling organic solvent. Low boiling volatile organic solvents evaporate quickly after applying paint on the road, providing the fast drying properties required for newly applied road marking.

However, in addition to the release of volatile organic solvents into the environment, the development of paint formulations exposes the operator to the organic solvent cycle. Due to these problems and recently increasing environmental regulations, more environmentally friendly coatings or paints are required while maintaining rapid drying.

More environmentally friendly coatings use aqueous polymers or resins than solvent-based polymers or resins.

Both aqueous and solventborne coating formulations comprise a binder polymer.

As used herein, the term “binder polymer” means a polymer that is included in the coating composition and that participates in the composition and enhances film formation of the resulting film.

First, due to the high boiling point, high latent heat of evaporation, high polarity and strong hydrogen bonding of water, the drying time of an aqueous paint or coating is generally longer than that of an organic solvent coating.

Drying time is highly dependent on the relative humidity of the atmosphere to which the coating is applied. Aqueous paints may take several hours or more to dry at high humidity. The problem when the drying time is delayed becomes more serious for thick films with thicker traffic markings (about 500 microns or more). Long drying time greatly reduces the applicability of water based paints. This is especially true for traffic roads and road marking paints because traffic blocking takes longer.

In addition, many studies have been conducted to keep white aqueous traffic paints white and prevent contamination for as long as possible after coating. However, the clean white surfaces of the newly painted traffic roads turned contaminated yellow or brown.

This discoloration phenomenon is called "yellowing".

Generally, the visibility of the paint is not largely affected, but the sulfidation is not preferable because aesthetics, in particular, a user of a traffic paint may be mistaken that the paint is a poor quality paint.

So far, there has been no explanation as to whether or not the disorder of the occurrence occurs immediately after the paint has been noticed.

In two cases where the same paint is painted on the same roadway, one case may be yellow and the other may not.

As a result of poor understanding of this problem, the solution could not be found.

As a result, the present inventors traced various possible causes for this phenomenon and found a solution.

The inventors believe that the yellowing phenomenon is caused by the reaction of iron and the material in the paint formulation to cause rust in the paint.

There is no obvious source of iron in the vicinity of the applied traffic paint. Perhaps it is believed to occur in cars driving on roads or in other components of the paint surface, such as asphalt.

Within 24 to 48 hours after the paint has been applied, iron can penetrate the paint in high humidity environments or during rainy weather and when the paint is not completely dry and still permeable to water.

After being introduced into the paint layer in this manner, it is believed that the water yellows by reacting with certain components of the paint to form a yellow or brown "rust" that contaminates the paint.

But in the case of heavy rain, iron and "rust" are washed away, which removes the yellow. Theoretical confirmation is difficult, but this may explain the disorder of yellow phenomenon.

EP-A-34383 discloses a top coating paint that protects the surface from external rust contamination, ie from rust from external sources that have fallen or adhered to the surface, which reacts with the iron in the rust to form colorless deposits. It contains a chelating agent.

GB 2172599A discloses a similar paint, which contains a chelating agent which is a polyphosphonate salt pigment.

None of these prior art documents discloses rust preventive paints or addresses the problem of traffic paints.

Japanese Patent Laid-Open No. 118840/1997 discloses a paint containing a chelating agent capable of chelation of iron ions, but this also does not mention the use of specific pigments.

Accordingly, an object of the present invention is to provide an aqueous coating composition that solves the conventional problems as described above.

According to the present invention there is provided an aqueous coating composition comprising a binder polymer and at least a pigment selected from the group consisting of zinc phosphate and calcium zinc phosphate.

According to another aspect of the present invention, there is provided a road marking aqueous coating composition comprising a binder polymer and at least a pigment selected from the group consisting of zinc phosphate and calcium zinc phosphate.

The present invention also provides a coating layer obtained by drying the composition.

The present invention also provides a road marking forming method comprising applying the water-based coating composition to the road surface.

The present invention provides a quick-drying aqueous coating composition that has good stability and can reduce or eliminate yellowing.

More specifically, the present invention provides a fast-drying road marking aqueous coating composition that is excellent in stability and can reduce or eliminate the sulfidation of newly applied road markings.

The invention can be used in numerous coatings, paints or marking applications. For example, the methods and compositions of the present invention can be used in traffic roads, road marking, house paints, interior and exterior surface walls, roofs, and other building repair coatings.

Substrate surfaces can be wood, metals (aluminum, iron and others), polymers, plasters and others.

Other applications include coated metal substrates present in various articles such as signs, boats, vehicles, and the like. All these substrates may already have one or more other coating or coating layers.

The coating composition of the present invention is suitable as a road marking aqueous coating composition as is generally applied to the road surface.

The term 'road' as used herein is a general term and includes any kind of indoor or outdoor solid surface that can be continuously or intermittently exposed or exposed to pedestrians, moving vehicles, tractors or airplanes.

Examples of such "roads" include highways, streets, driveways, sidewalks, runways, taxi areas, runways, parking lots, rooftops, indoor floors (plant floors, indoor shopping malls) and the like.

It is also within the scope of the present invention to apply a two or other-component aqueous coating to one or more new or old coatings or marking layers already painted on the surface.

The term "fast-drying" means that the drying time of the coating composition is shorter than that of other coating compositions, only that zinc phosphate and calcium zinc phosphate are not used.

The binder polymer of the present invention may have any composition and any molecular weight. The particular way in which the binder polymer is made is not critical to the present invention.

The binder polymers produce the desired polymers that are partially soluble or dispersed, soluble in bulk and solution polymerization, and by aqueous acid, suspension and emulsion polymerization, or in water or a mixture of water and water-miscible solvents, It can be prepared by any other method that can produce the desired polymer that can be dissolved, partially dissolved or dispersed in water or a mixture of water and a water-miscible solvent.

A preferred method of preparing the binder polymer is aqueous emulsion polymerization.

Polymers thus prepared are usually stabilized by the addition of anionic, nonionic or cationic surfactants or by incorporating cation or anionic fractions into the polymer itself during synthesis.

This emulsion polymerization is described in Blackley, D. C., Emulsion Polymerization, Applied Science Publishers: London 1975;

Odian, G. Principles of Polymerization; John Wiley & Sons: New York, 1991;

Emulsion Polymerization of Acrylic Monomers; Rohm and Haas, 1967; It can be carried out according to a number of processes described in the same document.

By "dispersed binder polymer" is meant a stabilized colloidal dispersion of binder polymer particles in an aqueous carrier.

By "dissolved binder polymer" is meant a water soluble binder polymer dissolved in an aqueous carrier.

"Binder polymer solid" refers to a binder polymer in a dry state.

"Pigment Dispersant" means a material used to improve the dispersion of pigment particles in a paint composition.

It is believed that the pigment dispersant is absorbed on the surface of the pigment particles in the paint composition to increase the upper (-) charge.

As a result, it is believed that the coulombic repulsion between the pigment particles is increased, thereby improving the pigment particle dispersion in the paint composition.

Preferably, the dispersed or dissolved binder polymer is, for example,

Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate isomer, butyl (meth) acrylate isomer, 2-ethylhexyl (meth) acrylate, isobornyl (meth) acrylate, isodecyl (Meth) acrylate, oleyl (meth) acrylate, palmityl (meth) acrylate, stearyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl ( C ₁ -C ₁₈ (meth) acrylate esters such as meth) acrylate, 4-hydroxy butyl (meth) acrylate, glycyryl (meth) acrylate;

Acrylamide or substituted acrylamide; (Meth) acrylonitrile;

Diacetone acrylamide; Acetoacetylethyl methacrylate;

Acrolein and methacrolein; Dicyclopentadienyl methacrylate;

Dimethyl meta-isopropenylbenzyl isocyanate; Isocyanatoethyl methacrylate; Styrene or substituted styrenes; butadiene; Ethylene;

Vinyl acetate or other vinyl esters;

Vinyl monomers such as, for example, vinyl halides, preferably vinyl chloride, vinylidene halides, preferably vinylidene chloride, N-vinylpyrrolidone;

Amino monomers such as, for example, N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl methacrylamide and oxazolidinoethyl ethacrylate; Can be.

Throughout this specification, the term "(meth) acryl" refers to both "methacryl" and "acryl".

For example, (meth) acrylic acid means both methacrylic acid and acrylic acid, and methyl (meth) acrylate refers to both methyl methacrylate and methylacrylate.

If necessary, the dispersed or stabilized binder polymer further comprises an acid functional group-containing monomer in the range of 0.5-20.0%, preferably in the range of 5-15%, where it is based on the total weight of the Percent (%) binder polymer.

The acid functional groups are, for example, semi-acids of acrylic acid, methacrylic acid, itaconic acid, crotonic acid, aconic acid, atroic acid, maleic acid, maleic hydride, fumaric acid, vinylbenzoic acid, and ethylenically unsaturated dicarboxylic acid. The result is the inclusion of one or more monoethylenically unsaturated carboxylic acid monomers such as esters, half-amides of ethylenically unsaturated dicarboxylic acids, and mixtures thereof in the monomer mixture.

Other suitable monomers include at least one monomethylitaconate, monomethyl fumarate, monobutyl fumarate, acrylamido propane sulfonate, sodium vinyl sulfonate, 2-acrylamido-2-methylpropane sulfonic acid, 2-methylacrylic Oxyethyl phosphate (MOP) and phosphoethyl (meth) acrylate.

Monomers containing the monoethylenically unsaturated carboxylic acid are preferred, and acrylic acid, methacrylic acid and mixtures thereof are more preferred.

Optionally, for example 0-5% by weight of allyl (meth) acrylate, diallylphthalate, 1,4-butylene glycol di (meth) acrylate, 1.6-hexanedioldi (meth) based on the weight of the dry polymer Low levels of multi-ethylenically unsaturated monomers having acrylates and trimethylolpropane tri (methyl) acrylate are sufficient to prevent uncontrollable viscosity in the case of solution polymers or to jeopardize effective film formation in the case of emulsion polymers. Can be used to maintain low levels of crosslinking.

The terms "coating", "film (film)" and "coating film (film)" are used interchangeably with each other to mean a film that is formed in a layer on the substrate surface and dried.

The traffic paint preferably comprises a multifunctional amine polymerized from one or more monomers.

If necessary, the traffic paint may comprise an amine modified dispersed or stabilized binder polymer or a mixture of dispersed or stabilized binder polymer and a multifunctional amine or a combination of the mixture and an amine modified binder polymer, preferably in equal proportions. Can be.

The mixture comprises 0-20%, preferably 0.5-10% and more preferably 2-5% multifunctional amine, with the percentage being based on the total weight of the mixture solids.

The multifunctional amine is polymerized from at least one class of the following amine containing monomers of 20-100%, preferably 50-100%, based on the total weight of the multifunctional amine.

Class 1. An alkyl group is straight or branched, and has 2-3 carbon atoms.

Aminoalkyls, wherein the nitrogen atom may be primary, secondary, or tertiary nitrogen atom

          Vinyl ether such a process is disclosed in US Pat. No. 2,879,178.

          One of the remaining hydrogen atoms is alkyl, hydroxyalkyl, or alkoxyalkyl

          When substituted with a group, the alkyl component is 1-4 carbon atoms, preferably

          Crab can have only one carbon atom.

          Specific examples include beta-aminoethyl vinyl ether; Beta-aminoethyl vinyl

          Sulfides; N-monomethyl-beta-aminoethyl vinyl ether or sulphi

          De; N-monoethyl-beta-aminoethyl vinyl ether or sulfide;

          N-monobutyl-beta-aminoethyl vinyl ether or sulfide; And

          N-monomethyl-3-aminopropyl vinyl ether or sulfide can be mentioned.

          All.

Class 2. Acrylamide or acryl ester such as

With the proviso that R is H or CH ₃ ,

           n is 0 or 1;

           X is 0 or N (H).

If n is 0, A is O (CH ₂ ) .x (x is 2 to 3) or (O-alkylene) Y ((O-alkylene) Y is a poly (oxylalkylene) group) and GPC The number average molecular weight is 88-348 and each alkylene group is the same or different and is ethylene or propylene; And when n is 1, A is an alkylene group having 2 to 4 carbon atoms;

R ^* is H, methyl or ethyl; And

R ^o is H, phenyl, benzyl, methylbenzyl, cyclohexyl, or (C ₁ -C ₆ ) alkyl.

Some preferred examples of compounds of formula I include

Dimethylaminoethyl acrylate or methacrylate;

Beta-aminoethyl acrylate or methacrylate;

N-beta-aminoethyl acrylamide or methacrylamide;

N- (monomethylaminoethyl) -acrylamide or methacrylamide;

N- (mono-n-butyl) -4-aminobutyl acrylate or methacrylate; Methacryl

Oxy ethoxyethylamine; And acryloxy propoxy propoxypropylamine.

have.

3. N-acryloxyalkyl-oxazolidine and N-arc represented by the following formula II:

          Aryloxy alkyl tetrahydro-1,3-oxazine and "alkyl" bonds are alkoxy

          Components corresponding to those substituted with alkyl and poly (alkoxy-alkyl).

(Ⅱ)

(Ⅱ)

Wherein R is H or CH ₃ ;

           m is a constant of 2-3;

R ¹ is hydrogen, phenyl, benzyl and (C ₁ -C ₁₂ ) when not directly bonded to R ² ;

           Selected from the group consisting of alkyl groups;

R ² , when not directly bonded to R ¹ , consists of hydrogen and a (C ₁ -C ₄ ) alkyl group

           Selected from the group to be;

When R ¹ and R ² are directly bonded to each other, the carbon atom of the ring

           To form attached 5- or 6-carbon rings, ie when bonded to one another

R ¹ and R ² in the group consisting of pentamethylene and tetramethylene

           Selected; And

A ′ is O (CmH ₂ m) or (O-alkylene) _n where (O-alkylene) _n is poly (jade

          Cylalkylene) groups, and these have a GPC number average molecular weight in the range of 88 to 348

          The individual alkylene radicals are the same or different and are either ethylene or

          Is propylene.

         Compounds of formula II are hydrolyzed under various conditions to form secondary amines.

         do.

         Hydrolysis produces a product having the following formula III.

        Compounds of formula III are disclosed in US Pat. Nos. 3,037,006 and 3,502,627.

        All. None of the monomer compounds disclosed herein can be incorporated into the compositions of the present invention.

        It can be used to prepare the copolymer used.

        As a preferable example of a formula III compound,

        Oxacridinylethyl methacrylate;

        Oxazolidinylethyl acrylate;

        3- (gamma-methacryl-oxypropyl) -tetrahydro-1,3-oxazine;

        3- (beta-methacryloxyethyl) -2,2-penta-methylene-oxazolidine;

        3- (beta-methacryloxyethyl) -2-methyl-2-propyloxazolidine;

        N-2- (2-acryloxyethoxy) ethyl-oxazolidine;

        N-2- (2-methacryloxyethoxy) ethyloxazolidine;

        N-2- (2-methacryloxyethoxy) ethyl-5-methyl-oxazolidine;

        N-2- (2-acryloxyethoxy) ethyl-5-methyl-oxazolidine;

        3-, 2- (2-methacryloxyethoxy) ethyl-2,2-penta-methylene-oxazolidine;

        3-, 2- (2-methacryloxyethoxy) ethyl-2,2-dimethyloxazolidine;

        3-, 2- (methacryloxyethoxy) ethyl-2-phenyl-oxazolidine;

        2-isopropenyl-2-oxazoline is mentioned.

Class 4. Polymers of monomers that readily produce amines by hydrolysis are multifunctional

          It is beneficial for the preparation of the sex amines.

          Examples of such monomers are acryloxy-gettimin, such as formulas IV and V.

          And acryloxy-aldimine.

Provided that R is H or CH ₃ ;

= Selected from the group consisting of CHR ³ ,

R ⁶ is H or methyl in one CHR ⁶ unit;

R ⁵ is selected from the group consisting of (C ₁ -C ₁₂ ) alkyl and cyclohexyl groups;

R ⁴ is selected from the group consisting of (C ₁ -C ₁₂ ) alkyl and cyclohexyl;

R ³ is phenyl, halophenyl, (C ₁ -C ₁₂ ) -alkyl, cyclohexyl, and (C ₁ -C ₄ ) alkoxy

         Selected from the group consisting of phenyl groups;

A ″ is an alkylene group (C ₁ -C ₁₂ );

A ^o , B and D are of the formula-OCH (R ⁷ ) -CH (R ⁷ ), where R ⁷ is H, CH ₃ or C ₂ H ₅

         Having or different oxyalkylene groups;

         x is a constant of 4 to 5;

n ^o is a constant from 1 to 200;

         n 'is a constant from 1 to 200; And

n ″ is 1 to 200 so that the sum of n ^o- 1, n′-1 and n ″ -1 is 2 to 200.

         Constant;

Preferred examples of the compounds of formulas IV and V include

2-, 4- (2,6-dimethyl heptylidene) -amino-ethyl methacrylate;

3-, 2- (4-methylpentyridine) -amino-propyl methacrylate;

Beta- (benzylideneamino) -ethyl methacrylate;

3-, 2- (4-methylpentyridine) -amino-ethyl methacrylate;

2-, 4- (2,6-dimethyl heptylidene) -amino-ethylacrylate;

12- (cyclopentylidene-amino) -dodecyl methacrylate;

N- (1,3-dimethylbutylidene) -2- (2-methacryloxyethoxy) -ethylamine;

N- (benzylidene) -methacryloxyethoxyethylamine;

N- (1,3-dimethylbutylidene) -2- (2-acryloxyethoxy) -ethylamine; And

N- (benzylidene) -2- (2-acryloxyethoxy) ethylamine is mentioned.

The compounds of formulas IV and V are hydrolyzed in an acidic, neutral, or alkaline aqueous medium to produce the corresponding primary amine or salt thereof, wherein -N = Q is -NH ₂ and O = Q.

Formulas IV and V are disclosed in US Pat. Nos. 3,037,969 and 3,497,485, and any monomeric compound disclosed herein may be used in the water-soluble polymer portion of the composition according to the present invention.

The binder polymer of the present invention typically has a glass transition temperature Tg value in the range of -10 ° C to 70 ° C, which has a poor resistance to dirt-pickup when having a Tg value of less than -10 ° C and is usually a film above 70 ° C. The forming force is reduced.

However, in some applications, the lower limit of Tg may be lower than -10 ° C. For example, the binder polymer used in the roof coating agent may have a Tg of about -40 ° C.

The Tg of the polymer is the temperature at which the polymer is solid at temperatures below Tg and converted to flowable or rubbery at temperatures above Tg in the glassy state.

Polymer Tg is typically measured by differential scanning calorimetry (DSC) using the midpoint in the temperature transition to heat flow as the Tg value. Typical heating rates for DSC measurements are 20 ° C / min.

Initiation of emulsion polymerization is also referred to as a free radical precursor, here an initiator, capable of generating radicals suitable for initiating addition polymerization.

By pyrolysis.

Suitable thermal initiators such as, for example, inorganic hydroperoxides, inorganic peroxides, organic hydroperoxides and inorganic peroxides are useful at the 0.05 to 5.0 weight percent level by weight of monomers.

Free radical initiators known in the aqueous emulsion polymerization art include water-soluble free radical initiators such as hydrogen peroxide, tert-butyl peroxide; Alkali metal (sodium, calcium or lithium) or ammonium persulfate; Or mixtures thereof.

Such initiators may also be combined with reducing agents to form a redox system.

Useful reducing agents include sulfites such as alkali metal meta bisulfite or hyposulfite, sodium thiosulfate, or sodium formaldehyde sulfoxylate.

The free radical precursor and the reducing agent, referred to herein as a redox system, can be used together at a level of 0.01 to 5% by weight of the monomers used.

Examples of redox systems include t-butyl hydroperoxide / sodium formaldehyde sulfoxylate / Fe (II) and ammonium persulfate / sodium bisulfite / sodium hydrosulfite / Fe (II).

The polymerization temperature may be 10 ° C. to 110 ° C. depending on the free radical initiator decomposition constant and the reaction vessel pressure capacity.

Chain transfer agents can be used in an amount effective to provide the required GPS weight average molecular weight.

In order to control the molecular weight of the polymer formed, suitable hex transfer agents include halo-organic compounds such as carbon tetrabromide and dibromo dichloromethane; Sulfur-containing compounds such as ethanethiol, butanethiol, alkylthiols including tert-butyl and ethyl mercaptoacetate and aromatic thiols; Or various other organic compounds having hydrogen atoms that are readily extracted by free radicals during polymerization.

Additional suitable chain transfer agents or components include, but are not limited to, butyl mercaptopylopionate; Isooctyl mercapto propionate; Bromoform; Bromotrichloromethane; Carbon tetrachloride; Alkyl mercaptans such as 1-dodecanethiol, tert-dodecyl mercaptan, octyl mercaptan, tetradecyl mercaptan and hexadecyl mercaptan;

Alkyl thioglycolates such as butyl thioglycolate, isooctylthioglycolate and dodecyl thioglycolate; Thioesters; Or mixtures thereof.

Preferred is mercaptan.

When a dispersion of polymer particles is used, the polymer particle size is controlled in accordance with the amount of conventional surfactant added during the emulsion polymerization process.

Conventional surfactants may be used to stabilize the emulsion polymerization system prior to, during and after the polymerization of the monomers.

These conventional surfactants will usually be present at levels of 0.1 to 6% by weight of the total monomers.

At least one anionic, nonionic or amphoteric surfactant or mixtures thereof may be used.

Optionally, all or part of the particle stabilization may be provided by an initiator fragment, such as that of the sulfate, when the fragment is incorporated into the polymer chain.

Examples of anionic emulsifiers are sodium lauryl sulfate, sodium dodecyl benzene sulfonate, dioctyl sulfosuccinate, sodium polyoxyethylenelauryl ether sulfate, sodium dodecyl diphenyl oxide disulfonate and other diphenyl sulfonates Derivatives, and sodium salts of tert-octylphenoxyethoxypoly (39) ethoxyethylsulfate.

Examples of nonionic surfactants include glycerol aliphatic esters, oleic acid monoglycerides, polyoxyethylene aliphatic esters, polyoxyethylene glycol monostearate, polyoxyethylene cetylether, polyoxyethylene glycol monolaurate, polyoxyethylene glycol monooleate , Polyoxyethylene glycol stearate, polyoxyethylene higher alcohol ether, polyoxyethylene lauryl ether, polyoxyethylene nonylphenol ether, polyoxyethylene octylphenol ether, polyoxyethylene oleyl ether, polyoxyethylene stearyl ether, Polyoxyethylene sorbitan aliphatic ester, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan Tantrioleate, polyoxyethylene sorbitan tristearate, polyoxyethylene sorbitol tetraoleate, stearic acid monoglyceride, tert-octyl phenoxyethylpoly (39) ethoxyethanol, nonylphenoxyethylpoly (40) Ethoxy ethanol can be mentioned.

Amphoteric surfactants may also be used alone or in combination with anions, nonionics or mixtures thereof to stabilize the polymer particles during and after aqueous emulsion polymerization or other dispersion polymerization.

Amphoteric surfactants may be used at levels of 0.1 to 6% by weight of the total monomers to stabilize polymer particles in aqueous systems.

Advantageous classes of amphoteric surfactants include amino carboxylic acids, amphoteric imidazoline derivatives, betaines and macromolecular amphoteric surfactants.

Amphoteric surfactants from these classes may also be substituted with fluorocarbon substituents, siloxane substituents or mixtures thereof. Useful amphoteric surfactants are Amphoteric Surfactants, ed. B.R. Bluestein and C.L. Hilton, Surfactant Series Vol. 12 Marcel Dekker NY.NY (1982).

If desired, the dispersed polymer may be of two or more phases, such as, for example, core / cell or core / cis particles, core / cell particles with a shell phase incompletely enclosing the core, core / cell particles with multiple cores, and penetration network particles. Multi-stage polymer particles having various geometries. In all these cases, most of the particle surface area is occupied by at least one outer phase and the interior of the polymer entry is occupied by at least one inner phase.

The outer phase of the multistage polymer particles accounts for 5-95% by total particle weight. Often each stage of the multistage polymer particles needs to have a different Tg.

If desired, each stage of these single stage polymer particles may be provided with other GPC number average molecular weights, such as the multistage polymer particle compositions disclosed in US Pat. No. 4,916,171.

Multistage polymer particles of the dispersed polymer are prepared by conventional emulsion polymerization processes in which at least two stages of different compositions are formed sequentially.

Such a process usually forms at least two polymer compositions.

Each step of the multistage polymer particle may contain a chain transfer agent, a surfactant as described above.

Emulsion polymerization techniques used to make such multistage polymer particles are well known in the art and are described, for example, in US Pat. No. 4,325,856; 4,654,397; 4,814,373 and 4,916,171.

Conventional zinc phosphate and calcium zinc phosphate can be used in the present invention.

Zinc phosphate (ZnPh) is a white powder having a ZnO / P ₂ O ₅ composition.

Calcium zinc phosphate (CaZnPh) is a white powder having a composition of CaO / ZnO / P ₂ O ₅ . Preferably particles having a diameter of 3 to 4 micrometers are used.

For example, the following commercially available products can be used in the present invention.

As zinc phosphate, Kikuchi Color Corp. LF Bousei P-W-2, and calcium zinc phosphate from KiKuchi Color Corp. LF Bousei CP-Z supplied by.

Zinc phosphate and / or calcium zinc phosphate is contained in the coating composition as about 10% pvc or less, preferably 0.1 to 0.5% pvc, more preferably 0.15 to 1.0% pvc, and most preferably about 0.5% pvc. do.

"pvc" means pigment volume concentration.

The composition of the present invention may also comprise conventional white pigments, preferably titanium dioxide, in the range of 5-20%, preferably 6-16%, based on the total weight of the composition.

An example of a suitable white pigment for use in the traffic paint of the present invention may deulsu those supplied by EI du Pont and company, Inc, Wilmington, Delaware as Tipure ^® titanium dioxide white pigment.

Other suppliers include TITAN ^® TR 92 from Tioxide, Cleveland, United Kingdom.

If necessary, the composition of the present invention may include 0.25 to 2% of a pigment dispersant based on the total weight of the polymer solids.

Suitable pigment dispersants include polymeric carboxylic acids and their ammonium and alkali metal salts.

Suitable polymeric carboxylic acids include polyacrylic acid, polymethacrylic acid, copolymers of (meth) acrylic acid and maleic acid, all of which typically have a weight average molecular weight ranging from 4000 to 10,000.

Examples of other suitable pigment surfactants include copolymers of meth (acrylic acid) and polar compounds (such as hydroxyethyl methacrylate) and copolymers of nonpolar compounds (such as butyl methacrylate) and maleic anhydride and diobutyrene It includes the reaction product of.

Polymethacrylic acid and ammonium and its alkali metal salts are preferred.

It is desirable to have additional components added to the coating composition to form the final blends for traffic paints and other coatings described herein. Examples of these additional ingredients include thickening agents; Rheology modifiers; dyes; Foaming agents; disinfectant; Dispersants; Pigments such as titanium dioxide, organic pigments and carbon black; Weight agents such as calcium carbonate, talc, clay, silica and silicates; Fillers such as glass or polymeric microspheres, quartz and sand; Cryoprotectants; Plasticizers; Adhesion promoters such as silanes; Binders; Wetting agents; Surfactants; Slip additives; Crosslinking agents; Antifoam; coloring agent; Tackifiers; Wax; Preservatives; Icing / thawing protectors; Corrosion inhibitors; And anti-condensing agents.

 In the road marking forming method of the present invention, a road marking aqueous coating composition is applied to a road surface.

This coating composition can be applied to the road surface by a number of methods known in the art, such as spraying.

If desired, glass beads may be applied to the road marking surface when the traffic paint is still wet to form reflective road markings with increased visibility.

Hereinafter, the present invention will be described in detail with reference to Examples.

This embodiment is by way of illustration of the invention in no way to limit the scope of the invention.

Example 1

The following materials were mixed to blend the coating composition.

In this example, the difference in sulfidation caused by calcium carbonate was measured.

matter Parts by weight

Binder Emulsion A 570.0

Dispersant OROTAN 901 6.2

Wetting Agent TRITON CF-10 3.4

Antifoaming agent FORMASTER VL 2.0

Titanium Dioxide Ti-Pure R-902 120pvc 4.9%

Calcium Carbonate 885.0pvc 53.7%

Methanol 33.5

Antifoaming agent FORMASTER VL 3.0

Adhesion Agent TEXANOL 28.5

Thickener HEC 2% 14.1

Water 7.0

Solid Volume% 61.5%

Solid weight% 76.9%

Fastrack 3427 (acrylic emulsion, supplied by Rohm and Haas Company, Philadelphia, USA, 50% solids, molecular weight = 50000, particle size 150 nm) was used as emulsion A.

OROTAN 901 is a dispersant (ammonium polyacrylate salt) supplied by Rohm and Haas Company.

TRITON CF-10 is a trademark of Union Carbide Chemical Inc. of Danbury, Conn. Wetting agent supplied by.

FORMASTOR is an antifoaming agent supplied by Henkel Corp.

Ti-Pure is E.I. Titanium dioxide from duPont De Nemours and Company.

TEXANOL is Eastman Chemical Co. of TN, Kingspot. Ester alcohol supplied by the company.

Yellowing test:

The binder polymer, dispersant, wetting agent and antifoaming agent were mixed.

Titanium dioxide and calcium carbonate were then added and mixed at 1000 rpm for 15 minutes.

In the three compositions of Example 2, 0.5 pvc calcium carbonate was substituted for zinc oxide, zinc phosphate and calcium zinc, respectively, and phosphate was added again with titanium oxide and calcium carbonate.

Then methanol, antifoam and binder were added again and mixed. Finally water and thickener were added to adjust the viscosity and solids content.

The coating composition thus obtained was applied to a black polyvinylchloride plate with a 15 mil applicator and dried at room temperature for 2 days.

Half of the plate with the dried coating layer was immersed in acid rain or deionized water and kept for 2 days in a solar greenhouse or dark place.

As the acid ratio, a solution composed of 5% Nacl 10 L, concentrated nitric acid 12 ml and concentrated sulfuric acid 17.3 ml, and adjusted to Ph with 10% NaOH was used.

Color difference was determined by MINISCAN (supplied by Hunter Associates Laboratory Inc.) by measuring L ^☆ / a ^☆ / b ^☆ of the non-soaked sites and delta E was calculated.

The results are shown in the table below.

Coating Number CaCO ₂ Sun / acid ratio Sun / DI water Darkness / acid ratio

   1 A (Australia) 7.0 3.8 1.0

   2 A (Korea) 3.0 0.7 0.2

   3 B (Japan) 0.9 0.3 0.5

   4 C (Japan) 0.9 0.5 0.4

Calcium Carbonate A is OMIYA Inc. Calcium Carbonate OMIYACARB 10 supplied by.

Calcium Carbonate B is produced by Maruo Calcium Inc. Calcium Carbonate Super S from.

Calcium Carbonate C is manufactured by Shiraishi Calcium Inc. Calcium carbonate Whiton B supplied by

Delta E of less than 1.0 is acceptable.

Example 2

Three coating compositions were prepared according to the procedure of Example 1 except that 0.5pvc calcium carbonate was replaced with zinc oxide (ZnO), zinc phosphate (ZnPh) and calcium zinc phosphate (CaZnPh), respectively.

Calcium carbonate A (Korea) was used as calcium carbonate.

The coating was tested for stability, yellowing and drying rate. As ZnO, Hakusui Kagaku Corp. Sangou Aenka supplied by was used.

LF Bousei P-W-2 supplied by Kikuchi Color Corp was used as zinc phosphate.

As calcium zinc phosphate, Kikuchi Color Corp. LF Bousei CP-Z was used.

Zinc phosphate was 65-70% zinc oxide and 22% P ₂ O ₅ and the rest was crystallized water.

Calcium zinc phosphate comprised 17% CaO, 40% zinc oxide and 21% P ₂ O _5, with the remainder being crystallized water.

Stabilization test and drying rate test method were performed as follows.

Stabilization test: Initial viscosity of the composition and the viscosity after storage for 10 days at 60 ℃

Measured.

Viscosity was measured by Ku as a Stormer viscometer.

In Example 4, the viscosity after storage for 10 days at room temperature

It is expressed as equilibrium viscosity.

Drying speed test: Coating composition was coated with an applicator to thickness 375 micro

It was applied on the glass plate by meter.

The time until the adhesive disappeared at 23 ° C./73% RH was measured.

Stabilization Test

    Coating number    Zinc Pigment                Viscosity   Early    After heating (60 ℃, 10 days)       2        -    80            85       5    CaZnPh    86            89       6    ZnPh    97           102 Soft Sedimentation       7     ZnO    90           Gel

Yellowing test

   Coating number    Zinc Pigment    Delta E (solar / acid ratio)     2        -     2.6     5    CaZnPh     0.7     6     ZnPh     0.7     7      ZnO     0.8

Drying time

   Coating number    Zinc Pigment    Drying time (minutes)     2       -       16     5    CaZnPh        8     6     ZnPh        8     7      ZnO        8

The results indicated that yellowing and drying time could be improved by adding zinc oxide, zinc phosphate and calcium zinc phosphate.

However, zinc oxide gels the coating composition over time.

On the other hand, zinc phosphate and calcium zinc phosphate had no adverse effect on the stability of the coating composition.

Calcium zinc phosphate gave the best results.

Example 3

The color difference and drying time for various amounts of calcium zinc phosphate were measured according to the formulation of Example 2.

   Coating number   CaZnPh, PVC%   Delta E   Drying time (minutes)      One      0    2.8     16      8      0.15    1.4     14      9      0.30    0.5     10      5      0.50    0.4      8     10      1.00    0.4      8

Increasing the calcium zinc phosphate to 0.5% pvc can be seen to improve the yellowing phenomenon and drying time.

However, even if the amount increased to 1.0pvc no further improvement. Therefore, the most preferable amount of calcium zinc phosphate is considered to be 0.5% pvc.

Example 4

Another binder polymer was used to investigate the effect of calcium zinc phosphate on the stability and drying time of the coating composition.

      matter     Composition 11   Composition 12    Parts by weight    Parts by weight  Binder Emulsion B    570.0    570.0  Dispersants OROTAN 901      6.2      6.0  Wetting Agent TRITON X-405      4.5      4.5  Antifoaming agent FORMASTER 8034      2.0      2.0 Titanium Dioxide Ti-Pure ^® R-902 148.0pvc 6.65%    148.0  Calcium Carbonate C 706.0pvc 47.0%    700.0  CaZnPh      0.0      8.0  Methanol     15.0     15.0  Antifoaming agent FORMASTER 8034      3.0      3.0  Adhesion TEXANOL     59.0     59.0  water     30.0     28.2  Ammonia Water (28%)      0      1.9  Solid content volume%     57.8%     57.8%  Solid content weight%     74.2%     74.2%

As the emulsion B, Fastrack 53 (acrylic emulsion, 51% solids, molecular weight = 50000, particle size 150 nm) available from Rohm and Haas Company was used.

Coating Number Drying Time (min) Viscosity KU

No viscosity after heating with heating (60 ℃, 10 days)

   11 40 93 99

   12 14 94 96

Coating composition 12 comprising calcium zinc phosphate exhibited an improved drying rate. The stability of the coating composition was not affected by the addition of calcium zinc phosphate.

Industrial availability

The composition according to the present invention has a fast drying time and yellowing is improved.

When the aqueous coating composition of the present invention is applied, not only is it quickly dried, but also yellowing is improved.

Claims (5)

A fast-drying aqueous road marking coating composition comprising a binder polymer and at least one pigment selected from the group consisting of zinc phosphate and calcium zinc phosphate. The road marking coating composition of claim 1 wherein the pigment is calcium zinc phosphate. delete A road marking coating layer obtained by drying the road marking coating composition of claim 1. A road marking forming method comprising applying the aqueous road marking coating composition of claim 1 to a road surface.