JPH04214783A - Chipping-resistant coating composition - Google Patents

Abstract

PURPOSE:To provide the title composition for automotive use, excellent in the resistance to corrosion, impact and chipping, etc., of the coating films therefrom, containing, as the essential coating film-forming components, polyurethane polyurea granules having three-dimensional crosslinked structure and binder resin. CONSTITUTION:The objective composition containing, as the essential coating film-forming components, (A) 100 pts.wt. of polyurethane polyurea granules having three-dimensional crosslinked structure produced from a polyisocyanate compound, polyhydroxyl compound and polyamine compound with the number- average molecular weight of said polyisocyanate compound falling between 200 and 10000 (esp. pref. 500 and 5000) and (B) 5-200 (pref. 10-150) pts.wt. of a binder resin consisting of a synthetic resin such as polyurethane resin, acrylic resin or alkyd resin or natural polymeric compound such as rubber or cellulose.

Description

[Detailed description of the invention]

0001

FIELD OF THE INVENTION This invention relates to new and useful pigmented or non-pigmented anti-chip coating compositions. More specifically, the present invention provides, inter alia, for the formation of a coating film comprising, as essential film-forming components, specific polyurethane polyurea particles each having a three-dimensional crosslinked structure and a binder resin. This invention relates to a chipping-resistant coating composition for automobiles, etc., which has excellent corrosion resistance, impact resistance, and chipping resistance.

0002

[Prior Art] In the automobile industry, the durability of paint films, especially
Deterioration of corrosion resistance due to impact peeling due to so-called chipping, which occurs when pebbles or the like collide with the paint film, and the accompanying progression of metal corrosion are viewed as problems. Until now,
In order to prevent such chipping and the progression of metal corrosion caused by the chipping, attempts have been made to improve the impact resistance of coating films against pebbles and the like.

[0003] Among them, as a general method, Japanese Patent Application Laid-Open No. 62-275169 or Japanese Patent Application Laid-Open No. 1-2
As disclosed in Japanese Patent Publication No. 04972, etc., by using a paint containing coarse pigment of 0.5 to 20 microns or diatomaceous earth of 4 to 25 microns, it is possible to add it to the paint film. There is a method of dispersing and absorbing the impact destructive force to soften the impact and, in turn, reduce damage to the metal base.

[0004] Also, Japanese Patent Laid-Open Nos. 55-56165 and 5
Publication No. 8-71968 also discloses a method of blending mica, talc, etc. in the form of flakes or scales, and it can be said that this method also aims at the same effect. Furthermore, Japanese Patent Application Laid-Open No. 64-85260 discloses a method in which spherical beads of a synthetic resin such as polyamide or vinyl polymer with an average particle diameter of 1 to 60 microns are blended into a paint. The method is
These synthetic resin particles absorb and disperse the impact that the paint film receives, thereby preventing the paint film from being destroyed or peeled off.

[0005]

[Problems to be Solved by the Invention] However, if such conventional methods are followed, the respective chipping-resistant materials themselves cannot sufficiently absorb and disperse energy when subjected to impact. As a result, there are extreme limitations in terms of the composition of the binder itself and the design of the paint used to develop chipping resistance.

[0006] As described above, conventional chipping-resistant paints do not have sufficient impact-absorbing structure, especially since the chipping-resistant material does not have a sufficient impact-absorbing structure.
The current situation is such that it is difficult to meet the needs for lighter weight and thinner films, which necessitates strict selection of binders or extreme increases in the amount of coating under low-temperature conditions.

However, in view of the various drawbacks of the prior art as described above, the present inventors focused on the unresolved problems of the prior art and began earnest research. Therefore, the problem to be solved by the present invention depends on one thing:
An object of the present invention is to provide an extremely useful chipping-resistant paint composition that has excellent chipping resistance, impact resistance, corrosion resistance, and the like.

[0008]

[Means for Solving the Problems] Therefore, the present inventors focused on the problems to be solved by the invention as described above, and as a result of intensive studies, we developed a polyurethane polyurethane polyurethane having a specific three-dimensional crosslinked structure. The present invention was completed by discovering that a coating composition comprising urea particles and a binder resin has the various properties described above.

That is, the present invention provides a pigmented or pigmented material containing polyurethane polyurea particles having a three-dimensional crosslinked structure and a binder resin as essential film-forming components. The object of the present invention is to provide a chipping-resistant paint composition that does not cause corrosion. Here, first, the polyurethane polyurea particles having the above-mentioned three-dimensional crosslinked structure are obtained from, for example, a polyisocyanate compound, a polyhydroxy compound, and a polyamine compound. Of course, known and commonly used compounds can be used as the compound.

[0010] Among them, only representative examples are tolylene diisocyanate, hydrogenated tolylene diisocyanate, diphenylmethane-4,
4'-diisocyanate, hydrogenated diphenylmethane-4
, 4'-diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, 1,3-bis(α,α-dimethylisocyanatemethyl)benzene, cyclohexyl-1 ,4
- aliphatic, cycloaliphatic or aromatic di- or triisocyanate monomers such as diisocyanate, oxadiazinetrione diisocyanate, isophorone diisocyanate or triphenylmethane diisocyanate; or trifunctional or higher functional polyisocyanurates based on these various monomers; These include various modified polyisocyanates such as type polyisocyanates and bullet type polyisocyanates, and further, one or more of the various diisocyanate monomers and modified polyisocyanates listed above, polyhydric alcohols, and polyesters. These include urethane-modified polyisocyanate prepolymers having terminal isocyanate groups obtained by urethanization reaction with one or more of various polyhydroxy compounds such as polyol, polycarbonate polyol, polybutadiene polyol, or polypentadiene polyol, and these may be used alone. However, two or more types may be used in combination.

In order for the obtained polyurethane polyurea particles (hereinafter also referred to as polymer particles) to have particularly excellent toughness, the number average molecular weight of the polyisocyanate compound should be in the range of 200 to 10,000. The number should preferably be selected within the range of 300 to 7,000, more preferably within the range of 500 to 5,000.

As the polyisocyanate compound, it is of course preferable to use a polyisocyanate compound consisting of an aliphatic and/or alicyclic diisocyanate, particularly in consideration of weather resistance. Further, the hydrophobic organic phase contains 10% by weight or more, preferably 20% by weight or more of a urethane-modified polyisocyanate compound obtained by reacting a polycaprolactone polyester polyol with a diisocyanate, based on the total polyisocyanate compound. By doing so, the toughness of the polymer particles can be further improved.

On the other hand, along with these polyisocyanate compounds, the polyhydroxy compound as a component constituting the organic phase compensates for the lack of internal crosslinking caused by the formation of the walls of the polymer particles, and further increases the mechanical strength of the particles. This polyhydroxy compound is an extremely important component in order to improve the performance, and any known and commonly used polyhydroxy compound can be used.

[0014] Among them, only the most representative ones belong to the following groups. a) Ethylene glycol, propylene glycol,
1,3-propanediol, 1,4-butanediol,
1,3-butanediol, 1,5-pentanediol,
Neopentyl glycol, 1,6-hexanediol,
1,4-bis(hydroxyethyl)cyclohexane, bisphenol A, hydrogenated bisphenol A, hydroxypivalyl hydroxypivalate, trimetrolethane,
Trimethylolpropane, 2,2,4-trimeryl 1
, 3-pentanediol, glycerin, hexanetriol, tris(2-hydroxyethyl)isocyanurate or pentaerythritol; b) polyoxetylene glycol, polyoxypropylene glycol, polyoxyethylenetetramethylene glycol, Polyether polyols such as oxypropylenetetramethylene glycol or polyoxyethylenepolyoxypropylenepolyoxytetramethylene glycol; c) Various polyhydric alcohols as listed above and ethylene oxide, propylene oxide, tetrahydrofuran, ethyl glycidyl ether, propyl various modified polyether polyols obtained by ring-opening polymerization reaction with glycidyl ether, butyl glycidyl ether, phenyl glycidyl ether, or allyl glycidyl ether; d) at least one of the various polyhydric alcohols listed above; Polyester polyols obtained by co-condensation reaction with polyhydric carboxylic acids, succinic acid, adipic acid, sebacic acid, succinic acid, adipic acid, sebacic acid, etc.
Azelaic acid, notaric acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, 1,2,5-hexanetricarboxylic acid, 1,4-cyclohexanedicaribonic acid, 1 , 2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid or 2,5,7 naphthalenetricarboxylic acid. e) Lactone-modified polyester polyols obtained by polycondensation reaction of at least one of the various polyhydric alcohols listed above and various lactones such as -caprolactone, δ-valerolactone or 3-methyl-δ-valerolactone; Alternatively, lactone-modified polyester polyols which can be obtained by polycondensation reactions of various polyhydric alcohols and polyhydric carboxylic acids with various lactones as listed above; f) Bisphenol A Various epoxy compounds, such as hydrogenated bisphenol A type epoxy compounds, glycidyl ethers of monohydric and/or polyhydric alcohols, or glycidyl esters of monobasic acids and/or polybasic acids, can be added to polyester polyols. At least one kind of epoxy-modified polyester polyols obtained in combination during preparation; further g)
These include polyester polyamide polyol, polycarbonate polyol, polybutadiene polyol, polypentadiene polyol, castor oil, castor oil derivatives, hydrogenated castor oil, hydrogenated castor oil derivatives, and hydroxyl group-containing acrylic copolymers.

It goes without saying that the polyhydroxy compounds shown in a) to g) may be used alone or in combination of two or more types, but their number average molecular weight is 200 to 10, 000, preferably 30
Within the range of 0 to 7,000, more preferably 500
A range of 5,000 to 5,000 is appropriate. In addition, in order to obtain tough polymer particles, it is desirable to use polyester polyols, especially lactone-modified polyester polyols obtained by polycondensation reaction with various lactones such as -caprolactone, δ-valerolactone, or 3-methyl-δ-valerolactone. It is preferable to use

In the present invention, the ratio of the isocyanate group equivalent of the polyisocyanate compound to the hydroxyl group equivalent of the polyhydroxy compound is 1:0.1 to 1.
; within the range of 0.9, preferably 1:0.1 to 1:0
．． 8, more preferably 1:0.1 to 1:
An appropriate range is 0.7, and the composition ratio should be such that both these components are mixed and the mixture of both components itself has a three-dimensional crosslinked structure and can be three-dimensionally crosslinked.

[0017] That is, when these mixtures are completely converted into urethane, they become gel-like and must be formulated in such a way that fluidity cannot be obtained even by heating or diluting the true solvent. The above-mentioned two conditions when designing the organic phase are essential for obtaining an internal crosslinked state and an internal crosslinked structure that cannot be obtained only by interfacial polymerization reaction by adding a polyamine compound as described below. This is one of the basic requirements of the present invention.

At this time, in order to make the interfacial polymerization reaction reasonably effective, it is necessary to have an excess of isocyanate groups according to the mixing ratio within the above-mentioned range. It is set to be formed. Furthermore, in the present invention, by allowing the urethanization reaction to proceed three-dimensionally inside the particles, it is possible to improve the toughness, solvent resistance, etc. of the entire particles, which could not be obtained with conventional techniques.

Due to the design of the three-dimensional wethanization reaction inside the polymer particles, a trifunctional or higher functional polyisocyanate compound and/or a polyhydroxy compound is combined with the polyisocyanate compound and polyhydroxy compound contained in the organic phase. A good three-dimensional cross-linked state inside the particles can be obtained by containing 0.1 mol % or more, preferably 0.2 mol % or more, more preferably 0.3 mol % or more of the total amount.

[0020] As the isocyanate groups in the polyisocyanate compound in the organic phase are consumed as the interfacial polymerization reaction with the polyamine compound described below progresses, the equivalent ratio of isocyanate groups and hydroxyl groups in the polymer particles approaches each other. However, the crosslink density inside the polymer particles further increases as the urethanization reaction progresses, and various properties such as toughness and durability of the polyurethane polyurea particles are further improved.

Further, as the pigment to be included in the present invention, known and commonly used organic pigments, inorganic pigments, and/or extender pigments are used, but only the most representative ones are exemplified. For example, as an organic pigment,
Insoluble azo pigments such as Benzidine Yellow, Hansa Yellow or Lake Red 4R; Soluble azo pigments such as Lake Red C, Carmine 6B or Bordeaux 10; Copper phthalocyanine pigments such as Phthalocyanine Blue or Phthalocyanine Green; Rhodamine Lake or Methyl Violet Lake. Basic dyeing lakes; acidic dyeing lakes such as quinoline lake or fast sky blue; mordant dye-based pigments such as alizarin lake; vat dye-based pigments such as anthraquinone, thioindigo, or perinone; Cyncasia Red B
quinacridone pigments such as; dioxazine pigments such as dioxazine violet; or condensed azometer pigments such as chromophthal.

Inorganic pigments include yellow lead, zinc chromate or chromate salts such as molybdate orange; ferrocyanic compounds such as deep blue; titanium white, zinc white,
Metal oxides such as mapico yellow, iron black, Bengara or chromium oxide green; sulfides or selenides such as cadmium yellow, cadmium red or mercury sulfide; sulfates such as barium sulfate or lead sulfate; calcium silicate or ultramarine silicates such as; carbonates such as calcium carbonate or magnesium carbonate; phosphates such as cobalt violet or manganese violet; metal powders such as aluminum powder, gold powder, silver powder or brass powder; or pearl pigments.

Extender pigments include precipitated barium sulfate,
Barium carbonate, powder, gypsum, white alumina, clay, silica, white silica, talc, calcium silicate, or precipitated magnesium carbonate, and carbon black that does not belong to both inorganic pigments and organic pigments. can also be used. These pigments are uniformly kneaded in advance with one or more of the above-mentioned polyhydroxy compounds and used as a mill base, but if necessary,
Chemical surface treatment of pigments before use or during kneading, combination of two or more pigments during kneading, or pigment dispersants and color separation agents known and commonly used in the paint and printing ink industries. Additives such as inhibitors can also be used in combination.

[0024] Such kneading can be carried out using a ball mill, a pebble mill,
This is carried out using a known and commonly used dispersing machine such as a sand mill, attritor, roll mill, high-speed impeller dispersing machine, or high-speed stone mill, and if necessary, organic solvents that are inert to hydroxyl groups and isocyanate groups are added. There is no problem in adjusting the viscosity of the kneading system. Suitable organic solvents that can be used are aromatic or aliphatic hydrocarbons, esters, ethers or ketones, and among them benzene, toluene, xylene, cyclohexane, methylcyclohexane, diphenyl ether or mineral spirit. There is.

The mixing ratio of the resin and the pigment in the mill base kneading step is within the range of 1 to 900 parts by weight, preferably 2 to 900 parts by weight of the pigment to 100 parts by weight of the resin solid content.
800 parts by weight, more preferably 5 to 500 parts by weight. The mill base thus obtained, a polyhydroxy compound, and a polyisocyanate compound are blended within the various ranges described above and mixed uniformly to form a hydrophobic organic phase. The proportion of the pigment used is within the range of 0.5 to 200 parts by weight, preferably within the range of 1 to 150 parts by weight, more preferably 2
A range of 100 parts by weight is suitable.

[0026] This hydrophobic organic phase is finely dispersed in an aqueous phase, and the excess isocyanate groups contained in the organic phase are
0.2 to 1 equivalent of polyamine compound per equivalent, preferably 0.3 to 1 equivalent, more preferably 0.4 to 0
．． A range of 9 equivalents is suitable. By adding in such a range, carrying out the urea-forming reaction at the particle interface, and carrying out the urethane-forming reaction inside the polymer particles, extremely tough pigmented polyurethane polyurea particles can be obtained.

The polyamine compounds used in the present invention are known and commonly used diamines, polyamines, or mixtures thereof. -ethylenediamine, bis(3-aminopropyl)amine, hydrazine, hydrazine-2-ethanol, bis(2-methylaminoethyl)-methylamine, 1,4-diaminocyclohexane, 3-amino-1-methylaminopropane, N-hydroxyethylethylenediamine, N-methyl-bis-( 3-aminopropyl)amine, tetraethylenediamine, hexamethylenediamine, 1-aminoethyl-1,2-ethylenediamine, bis(N,N-aminoethyl)-1,2-ethylenediamine, diethylenetriamine, tetraethylenepentamine, pentaethylenehexamine, phenylenediamine, toluylene diamine Amine, 2,4,6-triaminotoluline hydrochloride, 1,3,6-triaminonaphthalene, isophorone diamine, xylylene diamine, hydrogenated xylylene diamine, 4,4'-diaminophenylmethane, hydrogenated 4 ,4
'-diaminophenylmethane or derivatives of these polyamine monomers, etc., but from the viewpoint of weather resistance, it is desirable to use aliphatic and/or alicyclic systems.

In the present invention, the hydrophobic organic phase dispersed in water is non-reactive, and if necessary, a hydrophobic organic solvent is added to reduce the viscosity and improve the dispersibility in the aqueous phase. can be improved. As organic solvents that can be used, of course, the various compounds listed above may be used, as appropriate.
Of course, the organic solvent may be distilled off by heating, reduced pressure, or the like during or after the formation of the polymer particles, if necessary.

The aqueous phase in which the organic phase is dispersed contains a so-called protective colloid such as polyvinyl alcohol, hydroxyalkylcellulose, carboxyalkylcellulose, gum arabic, polyacrylate, polyacrylamide, polyvinylpyrrolidone or ethylene-maleic anhydride copolymer. It contains one or more of the following in an amount of 0.2 to 20% by weight. Further, this aqueous phase may contain various nonionic, anionic, or cationic surfactants within a range of 0.2 to 10% by weight.

The present invention is characterized in that the urethanization reaction is actively carried out inside the polymer particles, and as is known, the urethanization reaction between hydroxyl groups and isocyanate groups is particularly carried out by: When the isocyanate group is based on an aliphatic and/or alicyclic compound, the reaction tends to be slower than the ureation reaction with an amino group. As is well known, the reactivity of water with isocyanate groups is extremely small compared to that of hydroxyl groups, and due to the isolation effect of the outer wall formed by the addition of a polyamine compound, the penetration of water into the interior of the particles can be ignored. The purpose of the present invention, which is to carry out the urethanization reaction in particles by increasing the reaction temperature and taking time, is achieved, but the present inventors, in order to improve the above reaction conditions, After extensive research, we found cobalt naphthenate, zinc naphthenate, stannous chloride, stannic chloride, tetra-n-butyltin, tri-n-butyltin acetate,
One or more of various organometallic catalysts such as n-butyl trichloride, trimethyltin hydroxide, dimethyltin dichloride, dibutyltin diacetate, dibutyltin dilaurate, tin octenoate or potassium oleate are added to the hydrophobic organic phase. 5 to 10,000 ppm.
preferably 10 to 5,000 ppm. It has been found that by adding within this range, strong crosslinked polymer particles can be formed in an extremely short period of time.

These organometallic catalysts can very effectively promote the reaction between isocyanate groups and phosphoroxyl groups. Adding an organometallic catalyst such as those listed above to the organic phase prior to water dispersion (fine dispersion) increases the viscosity of the organic phase and reduces dispersibility in the water phase. Furthermore, adding an organometallic catalyst after adding a polyamine compound may cause the organometallic catalyst to be incorporated into the interior of the polymer particles due to the state in which the outer wall of the polymer particles is being formed. It becomes difficult to
Furthermore, since the effect of promoting the urethanization reaction inside the polymer particles tends to be reduced, the timing of adding the catalyst is during the water dispersion process in which the organic phase is dispersed in the water phase, or during the water dispersion process in which the organic phase is dispersed in the water phase. The period between the dispersion step and the middle of the polyamine compound addition step is most desirable.

[0032] The binder resin mentioned above can basically be any compound that can form a coating film. Various synthetic resins such as polyurethane resins, acrylic resins, alkyd resins, polyester resins, melamine resins, urea resins, epoxy resins, polyamide resins, vinyl acetate resins, vinyl chloride resins, and fluorine resins, to name but a few. and various rubbers such as natural rubber or synthetic rubber,
Furthermore, there are various natural polymer compounds such as cellulose, and it goes without saying that these may be used alone or in combination of two or more types.

[0033] In the present invention, the mixing ratio of the above-mentioned polyurethane polyurea particles and the binder resin is in the range of 5 to 200 parts by weight, preferably 10 to 150 parts by weight, based on 100 parts by weight of the resin solid content. The inside is appropriate. 5
If the amount is less than 200 parts by weight, the chipping property, which is important, will inevitably deteriorate, while if it exceeds 200 parts by weight, cracks will inevitably occur in the coating film. , both cases are unfavorable.

The chipping-resistant coating composition of the present invention includes:
In addition to the polyurethane polyurea particles and binder resin as described above, each of them contains various kinds of ordinary pigments, dyes, ultraviolet absorbers, smoothing agents (smoothening agents), anti-settling agents, or thixotropic agents. Of course, additive components may be added and mixed. Therefore, in particular, when coloring the composition of the present invention, it is of course recommended to use polymer particles containing pigments as they are, but as long as it does not depart from the purpose of the present invention. Moreover, there is no problem in adding pigments, dyes, etc. for coloring as long as the features and effects of the present invention are not impaired.

In order to actually form a chipping-resistant coating film using the chipping-resistant coating composition of the present invention,
First, the chipping-resistant paint of the present invention containing polyurethane polyurea particles is coated on an electrodeposited plate, then a regular intermediate coat is coated, and a top coat is further coated; Instead of using an intermediate coat, two methods are recommended: directly applying the chipping-resistant paint of the present invention onto the electrodeposited plate, and then applying a top coat.

[0036] There are no particular restrictions on the conditions for forming a coating film in order to fully develop the chipping resistance of the coating composition of the present invention.
You can select it as appropriate. The dry coating thickness of the composition of the present invention is suitably within the range of about 10 to 500 microns. If the thickness is less than 10 microns, the physical properties during chipping will inevitably be inferior, while if it exceeds 500 microns, which is too thick, the appearance of the coating will inevitably deteriorate. It cannot be said that it is preferable either.

[0037]

[Function and effect] When a coating system using the chipping-resistant coating composition of the present invention receives a chipping impact caused by pebbles, the polyurethane polyurea particles dispersed in the coating film are removed from the urethane resin. Due to its unique toughness and rebound resilience, it absorbs and disperses the destructive force caused by the impact, thereby preventing scratches on the paint film from reaching the metal base.

Furthermore, the structure of the particles is composed of soft segments and hard segments, and the composition of the particles can be adjusted to prevent chipping in a wide temperature range.
It is possible to use them properly as needed. That is, for chipping resistance at lower temperatures, the composition of the particles is made softer, while for chipping resistance at higher temperatures, it is made harder. Good chipping resistance can be obtained.

Furthermore, the particles have a three-dimensional crosslinked structure, so that even when baked at high temperatures, unlike conventional thermoplastic polymer particles, they are not limited by baking conditions.

[0040]

[Examples] Next, the present invention will be explained by reference examples and examples.
This will be explained in more detail. In the following, all parts and percentages are based on weight unless otherwise specified. Note that the raw material components used in each example will be explained in advance as follows. (A): Polyisocyanate compound 1) "Burnock DN-950" [Hexamethylene diisocyanate, manufactured by Dainippon Ink & Chemicals Co., Ltd.
A solid content of an adduct type polyisocyanate resin; solid content equivalent isocyanate group concentration = 16.8% was used, and hereinafter this will be referred to as PI-1.

2) “Burnock DN-980S” (manufactured by the same company,
An isocyanurate-type polyisocyanate resin obtained using hexamethylene diisocyanate (isocyanate group concentration = 21.0%) was used, and below, this was
-2. 3) 1,6-hexamethylene diisocyanate was also used, hereinafter abbreviated as HDI. (B): Polyhydroxy compound 1) Obtained by co-condensation reaction of neopentyl glycol and adipic acid, with a hydroxyl value of 18
A polyester polyol No. 7 was used, which will hereinafter be referred to as PO-1.

2) A polycaprolactone polyester polyol having a hydroxyl value of 187 obtained by a polycondensation reaction of neopentyl glycol and -caprolactone was used, and hereinafter this will be referred to as PO-2. (C): Polyamine Compound 1) Ethylenediamine was used, hereinafter abbreviated as EDA.

2) 1,6-hexamethylene diamine was used, hereinafter abbreviated as HMDA. Reference example 1 (Preparation example of polyurethane polyurea particles) 1
,000ml of "PVA-217" [partially saponified polyvinyl alcohol manufactured by Kuraray Co., Ltd.]
．． While adding 300 parts of a 2% aqueous solution to form an aqueous phase, in another container, 55.7 parts of PI-1, 9.3 parts of HDI, and 30 parts of PO-1 were mixed, and this was mixed with an organic It was a phase.

[0044] At room temperature (approximately 20°C), use a homo mixer at 7,000 to 7,500 rpm. While stirring the aqueous phase, the organic phase prepared in advance was added thereto, and the mixture was stirred for 1 minute to obtain a dispersion. Next, this dispersion was transferred to another flask and stirred using a paddler type stirring blade.
00rpm. 0.18 part of di-n-butyltin dilaurate (DBTDL) was added while stirring at
21.7 parts of a 50% aqueous solution of HMDA was also added.

After being kept at room temperature for 2 hours, the temperature was raised to 50°C and the reaction was continued at the same temperature for 1 hour and then at 80°C for 2 hours to obtain the desired suspension of polyurethane polyurea particles. . The average particle size of the particles was 30 microns. In addition, these particles do not swell or dissolve in general-purpose organic solvents such as acetone, ethyl acetate, or xylene, and are extremely stable.Furthermore, the particles are fully filled with polymer to the inside. As a result of observation using an electron microscope, it was confirmed that this was the case. Reference Example 2 (Preparation Example of Polyurethane Polyurea Particles Containing Pigment) First, 80 parts of PO-2, "Fastogen Super Red"
) 7093Y'' [a quinacridone organic pigment manufactured by Dainippon Ink and Chemicals Co., Ltd.] and 25 parts of toluene were mixed and dispersed for 1 hour using a sand grinder to obtain a red mill base. . Below, this is MB
It is abbreviated as -1.

[0046] Next, in a 1,000 ml flask,
Add 300 parts of a 0.2% aqueous solution of ``PVA-217'' to 7,000 to 7,000 parts by homomixer at 20°C.
500rpm. While stirring, add the organic phase prepared by mixing 37.5 parts of MB-1, 16 parts of PO-1, 30 parts of PI-1, and 20 parts of HDI in a separate container. and further add 0.2 part of DBTDL,
A dispersion was obtained by stirring for 1 minute.

Thereafter, this dispersion was transferred to another flask and stirred at 200 rpm using a paddler type stirring blade. While stirring, 22.3 parts of a 25% aqueous solution of EDA was added. After keeping at room temperature (approximately 25℃) for 2 hours, the temperature was raised to 50℃ and kept at the same temperature for 1 hour, and then at 80℃ for 2 hours.
The reaction was allowed to continue for a certain period of time to obtain the desired suspension of pigmented red polyurethane polyurea particles.

The average particle diameter of the polymer particles obtained here was 37 microns. Further, the particles did not swell or dissolve in acetone, and therefore no red pigment was observed to flow out in acetone. Reference example
3 (Preparation example of polyurethane polyurea particles for control) 1
0.000 ml of "PVA-217" into a 0.000 ml flask.
While charging 300 parts of a 2% aqueous solution to form an aqueous phase, in a separate container, 42 parts of PI-1 and 30 parts of PO-1 were added in advance.
The mixed organic phase was heated at 20° C. in a homomixer at 7,000 to 7,500 rpm. While stirring the aqueous phase under these conditions, a dispersion was obtained by stirring for 1 minute after the addition.

Next, the reaction was carried out by holding at 25°C for 2 hours, then at 50°C for 1 hour, and then at 80°C for 2 hours to continue the reaction. , control polyurethane polyurea particles were obtained. The average particle diameter of the polymer particles thus obtained was 25
It was a micron. Moreover, the polymer particles were completely dissolved in all common organic solvents such as acetone, ethyl acetate, and xylene.

Example 1 First, the polyurethane polyurea particles obtained in Reference Example 1 (
Hereinafter, this will be abbreviated as A-1. ), and mixed according to the composition ratio shown below, and mixed "Beccolite M-6402-50" [Dainippon Ink Chemical Co., Ltd. 600 parts, amino resin-modified saturated polyester manufactured by Kogyo Co., Ltd.]
"Super Beckamin L-127-75B" (manufactured by the same company)
171 parts melamine resin) particles (A-1)

286 parts calcium carbonate

782 parts carbon black

The meat was ground in a 2-part sand mill for 1 hour.

Next, “Naicure 2500X” [
9 parts of para-toluenesulfonic acid amine blocked product manufactured by Kusumoto Kasei Co., Ltd. were added, and "Solvesso 100
” (petroleum-based solvent manufactured by Exxon)/butyl carbitol acetate = 1:1 (weight ratio) thinner with a B-type viscometer of 4,000 to 5,000 cps. (Non-volatile content = 70%) and coated on a cationic electrodeposited plate with an airless coating machine to a dry film thickness of 150 microns, set for 1 minute, and heated at 140℃ for 20 minutes. Cured by heating.

[0052] Next, an intermediate coat and a top coat, such as those normally used for automobile coating, were applied onto the thus obtained coating film and cured by heating. The obtained cured coating film was evaluated and studied for various coating film properties including chipping resistance. The results are summarized in Table 1.

Example 2 “Acrydic A-409” (acrylic resin manufactured by the same company) 400 copies “Super Beckamine L-127-75B”
171 parts particles (A-1)

286 copies
calcium carbonate

782 parts carbon black

Two parts of these kneaded products were mixed with Ford Cup No. 1 using the same thinner as in Example 1.
．． Adjust the viscosity so that it takes 15 seconds with 4, and the viscosity is 40 kg/c.
Painted on a cationic electrodeposited plate using m2 air spray,
Heat curing was performed at 150° C. for 20 minutes.

Thereafter, in the same manner as in Example 1, an intermediate coat and a top coat were applied and cured by heating to obtain a cured coating film. Example 3 "Beccosol p-786-50" (Epoxy 400 parts ester manufactured by the same company) Particles (A-1)

200 parts calcium carbonate

750 parts carbon black

2 parts After kneading these mixtures in a sand mill, ``Burnock D-750'' (36 parts of tolylene diisothi, anate hardening agent manufactured by the same company) was added, and the mixture was coated in the same manner as in Example 2, and heated at 80°C for 30 minutes. Heat curing was performed for 1 minute.

[0055] Thereafter, in the same manner as in Example 2, an intermediate coat and a top coat were applied and cured by heating to obtain a cured coating film. Example 4 The pigment-containing polyurethane polyurea particles obtained in Reference Example 2 (hereinafter abbreviated as A-2) were used, and the intermediate coating was omitted.

"Burnock DS-1600" (250 parts of polyester manufactured by the same company)
polyol) particles (A-2)

100 parts calcium carbonate

100 parts These mixtures were kneaded for 1 hour in a sand mill, and then mixed with 160 parts of "Burnock DN-980" (HDI-based isopropylene manufactured by the same company).
Anate curing agent) was added, diluted with a thinner consisting of xylene/n-butyl acetate/butyl carbitol acetate (weight ratio) of 1:2:1, coated, and heat-cured at 80° C. for 30 minutes.

Next, a top coat was applied and cured by heating to obtain a cured coating film. Example 5 "Epicron 1050" (100 parts of bisphenol A type manufactured by the same company)
epoxy resin) particles (A-2)

58 parts calcium carbonate

30 copies
After kneading these mixtures in a sand mill for 1 hour, we send them here as Laccamide TD-973.
(75 parts of polyamide resin manufactured by the same company) was added, and xylene/n-butanol = 1:1 (weight ratio)
It was diluted with water, coated, and cured by heating at 100°C for 30 minutes.

Next, a top coat was applied and cured by heating to obtain a cured coating film.

[0059]

[Table 1]

[0060] The tests listed in Table 1 were conducted in the following manner. First, both adhesion properties were based on a grid adhesion test. Next, the impact resistance was measured according to the DuPont method, with a 1/2 inch notch, and was expressed as the height (fall length) at which a 1 kg load was dropped and scratches appeared on the coating film.

[0061] The chipping resistance was also expressed as a numerical value determined by the following calculation formula. (Area of cracks and peeling of paint film) / (Total area of paint film) ×
100(%) Furthermore, the chipping resistance after the humidity test is 50℃±5℃
240 in a blister box with 98% RH.
It is after being left alone for some time. As is clear from Table 1, it is known that all of the chipping-resistant coating compositions of the present invention provide excellent cured products.

[0062]

Effects of the Invention In the polyurethane polyurea particles of the present invention thus obtained, the reaction has been sufficiently completed to such an extent that no trace of unreacted isocyanate groups can be observed inside. Therefore, the polyurethane polyurea particles of the present invention are extremely tough and have particularly excellent chipping resistance, impact resistance, and corrosion resistance, and also have the extremely excellent characteristics of being applicable over a wide range of temperature ranges. ing.

Claims (3)

[Claims] [Claim 1] 1. A chipping-resistant coating composition comprising polyurethane polyurea particles having a three-dimensional crosslinked structure and a binder resin as essential film-forming components. 2. The above-mentioned polyurethane polyurea particles having a three-dimensional crosslinked structure are made into an organic phase in which a polyisocyanate compound and a polyhydroxy compound are mixed in such a manner that the isocyanate group is stoichiometrically excessive, Moreover, an interfacial polymerization reaction between an organic phase capable of forming a three-dimensional crosslinked structure by reaction and a polyamine compound in an equivalent or less amount relative to the stoichiometrically excess isocyanate groups in the organic phase; The chipping-resistant coating composition according to claim 1, which is obtained through a urethanization reaction inside the particles. 3. The above-described polyurethane polyurea particles having a three-dimensional crosslinked structure contain a pigment and are a mixture of a polyisocyanate compound and a polyhydroxy compound such that isocyanate groups are stoichiometrically excessive. between an organic phase that can form a three-dimensional crosslinked structure by reaction, and a polyamine compound in an equivalent or less amount relative to the stoichiometrically excess isocyanate group in the organic phase. The chipping-resistant coating composition according to claim 1, which is pigmented polyurethane polyurea particles obtained through an interfacial polymerization reaction of and a urethanization reaction inside the particles.