CA1266142A - Coating resinous composition containing saturated alicyclic acid modified amphoteric polyester resin - Google Patents

Abstract

Abstract Novel coating use resinous composition comprising an amphoteric polyester resin whose acidic groups capable of developing resinous acid value are controlled in kind and which is modified with saturated alicyclic acid, and etherified amino - formaldehyde resin. This resinous composition is characterized by having all of the advantages possessed by oil - free polyester resin composition as weather resistance, mechanical properties of the coating , interlaminar adhesion and the like, and furthermore, being excellent, inter alia, weather resistance because of the adoption of saturated alicyclic acid modification, curing property because of the control of acidic groups capable of developing resinous acid value, and pigment dispersibility and compatibility with melamine resin because of amphoterization.
The invention also provides a coating composition containing as vehicle the abovementioned resinous composition.

Description

The present invention relates to a resinous composition for coating use and more specifically, -to a novel resinous compo-sition comprising a sa-turat2d alicycllc acid modified amphoteric polyester resin whose acid groups capable of developing the resinous acid value are controlled in kind (hereinaf-ter called as acid controlled modlfied ampho-terlc polyester resin) and an etherified amino-formaldehyde resin, having all of the advantages possessed by oil-free polyes-ter resinous composition as weather resistance, mechanical proper-ties of the film, interlaminar adhe-sion and the like, and being fr~e of all of the drawbacks pos-sessed by polyester resinous composltion, since the weather resistance is greatly improved by the saturated alicyclic acid modification, curing property is by the control of the kind of acid groups capa~le of developing the resinous acid value and 15 p~ gment dispersibility and compatibility with melamine resin are by the amphoterization thereof.

Heretofore, as a top coat for automobile bodies and -the like, have been welcomed coating compositions based essentially on amino alkyd resin, amino acrylic resin or the like. However, in the former, though the application characteristic and finish-ing appearance ~gloss, glamorous) are comparatively good, there is a problem of inferior weather resistance, whereas in the lat-ter, though the weather resistance is excellent, there remain questions of inferior finishing appearance, impact reslstance and the like.

On the other hand, an oil-free polyester/aminoaldehyde resin type coating composition has been believed to be hardly applicable as a top coat to automobile bodies and the like, because the composition has the problems of application diffi-culty (generation of fish eyes), inferior gloss and poor compati-bility with amino resin or the like, irrespective of various advantages as excellent weather resistance, mechanical properties of the coating and interlaminar adheslon and the like.

Poor pigment dispersibility was also a big factor of k~eping it from -the actual use in coating area.

Recen~ly, various a-ttempts have been made on the oil-s fre~ polyester/amino formaldehyde resln -type coating composition, to make the most of the advantages and overcome the drawbacks possessed by the said composition thereby enabling it to apply to as a top coat for automobile bodies and -the like. Among them, particular attention has been concentrated to saturated alicyclic acid modified polyester resin consisting essentially of oil-free polyester -to which particular amounts of saturated alicyclic polycarboxylic acid are included as an acid component thereof (see Japanese Patent Application Nos. 94269/79 laid open as Japanese Patent Application Kokai ~o. 20068/81 and 111062/80 laid open as Japanese Pat~nt Application Kokai No. 36149/82).

However, indeed the abovementioned modified polyester/aminoaldehyde resin type coating composition may give improved weather resistance and somewhat improvements in such respects possessed as drawbacXs by the heretofore known oil-free polyester composition as generation of fish eyes and poor compat-ibility with amlno resins, but it is hardly possible to say that the abovementioned drawbacks are thoroughly solved out by the said compositions and there still remains a question of inferior pigment dispersibility and moreover produces an additional prob-lem of insufficient curability due to the modiflcatlon with ali-cyclic acid. Thereforer such compositions had not been practi-cally used after all.

The present invent~on, thsrefore, provides a polyester base resinous composition for coating use having the merits o*
heretofore known oil-free polyester/amino resin type coating com-position and being free of all of the demerits of using modified polyester resin as generation of fish eyes, poor compatibility with amino xesin, inferior pigment dispersibility and lnsuffi-cient curing property.

- 2 According to -the invention, is provided a resinous com-position for coating use comprising 60 to 90% by weight of polyester resin and ~0 to 10~ by weight oE amino-formaldehyde resin etherified with mono-hydric alcohol having 1 to 4 carbon atoms, which is characterized by sa~d polyester resin is an acid controlled modified ampho-teric polyester resin obtained by the reaction of polyester resin (A). 10 to ~0 mole~ o~ the acld com-ponents being occupied by saturated alicyclic polycarboxylic acld and 10 to 100 mole% of the carboxyl groups capable of developing the resinous acid value being derived from the polycarboxylc acid which may give a titration midpoint potential in a non-aqueous potentiometric titration under the state capable of developing resinous acid value of more than -350mv, and basic resin and/or bas~c compound (B).

In the present specification and claims, the term "carboxyl groups capable of developing resinous acid valuel' shall mean l'carboxyl groups capable of developing acid value of polyester resin"; the term ~under the state capable of developing resinous acid value" means "carboxylic acid under the state being incorporated into a polyester resin as the sole acid component thereof". Furthermore, the term "polyester resin" shall include both oil-free polyester resin and alkyd resin.

The present invention will be illustrated by way of the accompanying drawings, in which:-Fig. 1 shows non-aqueous potentiometric titration curves of acid controlled modified polyester resinous varnish A
~1) and of polyester prepolymer A-l (2) (Synthetic Example 1).
The present polyester resin, one component of the pre-sent resinous composition, is an acid controlled modified ampho-teric polyester resin obtained by the reaction o~ modlfied polyester resin(A) whose carboxyl groups capable of developing resinous acid value are controlled ln kind and basic resin and/or ~ 3 --..~ `.d.

basic compound (B). The modified polyester resin(A) whose car-boxyl groups capable of developing reslnous acid value are con-trolled in kind and which is used as a starting material 'n the invention is, as precisely stated in Japanese Patent Application No~ 154210/82 laid open as Japanese Patent ~pplicati.on Rokai Mo.
~3067/84 polyest~r resinous composition and preparation thereof, the modified polyester resin having as acid components saturated alicyclic polycarboxylic acid, polycarboxylic acid whose titra-tion midpoint potential in non-aqueous potentlometric titration, under the state capable of dev~loping resinous acid value, is more than -350mV, and optional other poly- and/or mono-carboxylic acid, 10 to 80 mole% of the total acid components being occupied by tlie a~oresaid saturated alicyclic polycarboxylic acid and 10 to~100 mole% of the carboxyl groups capable of developing resinous acid value being derived from the abovementioned poly-carboxylic acid whose titration midpoint potential in non-aqueous potentiometric titration, at the sate capable of developing resinous acid value is more than -350mV. Such modified polyester resin (A) whose carboxyl groups capable of developing resinous acid value are controlled in kind, supposing the acid components consisting of a mole of saturated alicyclic polycar-boxylic acid ~1) b mole of the polycarboxylic acid whose titra-tion midpoint potential in non-aqueous potentiometric titration ~ .~i ,~, Z
at the state capabl.e o:E developine resinolls acid vallle is more than - 350mV (2) and c mole of other poly - and/or mono - carboxylic acid (3~ (wherein a + b -~ c ~ 1.0 mole; O ~ c mole ;

10 ~ - x 100 ~ 80 ~ole%
a -~ b + c may be preferably and advantagcously prepared by the combination steps of reacting an acid mixture of a mole of (1) acid, (b- b1 ) mole o~
(2) acid and c mole of (3) acid, with polyhYdric alcohol to obtain a polyester prepolymer having a resinous acid value of M, in which M = N ( 1 - ) and then adding bl mole of (2) acid and continuing the esterification until the resinous acid value of N.
In the abovesaid statement, b1 is equal to b or less than b mole and denotes athe amounts of (2) acid to be charged in a later stage and deter~ined by the folloving equation :

- x N x W

bl = x x s6100 f 1 -~herein N stands for resinous acid value (KOH mg required for the neutrallzation of 1 g of resinous solid matter) ; W is polyester resin weight ; f is number of functional groups possesed by (B) ;
P is reaction percentage (%) of (2) at the later charging stage; x is~mole % of (B) occupied in the.carboxyl groups capable of developing reslnous acid value and dcternlined in a range of 10 ~ x ~ 100.
Among the said acid components, examples o~ saturated alicyclic poly -carboxylic acid (1) are cyclohexane ring bearing alicyclic acids as, for example, 1,l- cyclohexane dicarboxyl.ic acid,hexahydrophthalic acid and its anhydride, 1,3 - cyclohexane dicarboxylic acid,1,4 - cyclohexane dicarboxylic ac:id, met;hylhexahydr~phtha:Lic acid and its anhydride, hexahydrotrimelliitic acid and it5 anhydride ,and hexahydro 2- meth~l - trimellitic acid and its anhydride.
Examples o~ polycarboxylic acid having the titration midpoint poten -tial in non - aqueous potentiometric titration under the state being capable of develoying resinous acid value Oe more than - 350 mV are aromatic polycarboxylic acids as phthalic anhydride, isophthalic acid, terephthalic acid, trimellitic anhdyride, pyromellitic anhydride and the like. Such polycarboxylic acid per se will, in general, show, when made an electric potential - TBAH titer curve from the test results o~ non - aqueous potentiometric titration, a curve having multi - stage in~lection points, and however, ~hen incorporated in polyester chain, at least one carboxyl group will remain in free state and the corresponding curve will have the diminished number of inflection points, accordingly.
Under such conditions, if a polycarboxylic acid is possessed of such acid strength that the aforesaid titration midpoint potential is more than - 350 mV, then such a member may advantageously be used for the object of the present invention .
As the acid components, other poly - and/or mono - carboxylic acids (3) than the abovesaid (1) and (2) may be present, if desired. Such acid

(3) may be any o~ the members customarily used as an acid component of polyester resin, includin~ aliphatic or partially saturated alicyclic acids like succinic acid and its anhydride, adipic acid, azelaic acid, sebacic acid, tetrahydrophthalic anhydride, maleic anhydride, fumaric acid , itaconic acid and the like. Furthermore, monocarboxylic acids as benzoic acid, p - t- butyl benzoic acid and the like may be added for the purpose of regulating the molecular weight o~ the resin.
The polyhydric alcohol component to be reacted with said acid mixture is not o e speci~ic type and suitably selected -~rom the members customarily used :Eor the preparat;ion oL' polyec:ter resirls. ~xample5 oE
such members are ethylene1rlycol, cliethyk-~rleglycol, propyleneglyco], neopentylglycol, 1,2- butyleneglycol, 1,3- butyleneglycol, 2,3- buty -leneglycol, 1,4- butyleneglycol, 1,6 - hexanediol, 1,5-pentanediol, 2,5- hexanediol, trimethylolethane, trimethylolpropane, glycerin, pentaerythritol, diglycerin, sorbitol, 1,4- cyclohexAne dimethanol and the like.
As already stated, the resin (A) which constitutes the present acid controlled modified amphoteric polyester resinous component must be of the nature such that 10 to 80 mole% of the total acid components be occupied by said saturated alicyclic polycarboxylic acid and lO
to lO0 mole % of the carboxyl groups capable oE developing res~nous acid value be derived from the polycarboxYlic acid which will show a titration midpoint potential in non - aqueous potentiometric titration , under the state of carboxylic acid capable of developing resinous acid value , of more than - 350mV. This is because, if the content oE saturated alicyclic polycarboxylic acid is less than lO
mole % of the total acid components, there is a trend that weather resistance may not be improved, whereas if it exceeds over the upper limit of 80 mole % , chemical resistance be lowered. As the ratio o-E
carboxyl groups being responsible to the develoPment of resinous acid value, if the amount of said polycarboxylic acid having athe specified acid strength is less than lO mole % , then there is a general trend of giving insufficient gloss and curing property and hence, the object of the present invention cannot be attained.
It is true that an attempt had been once made to use the combination of alicyclic polycarboxylic acid and aromatic carboxylic acid in particular weight ratio (as shown in Japanese Patent Application Kokai No. 36149/82~ as acid components Eor the synthesis o:E polyester resin.
However, for the reaction with alcohol component, a carboxylic acid having an alicyclic structure as cyclohexarle ring is less reactive than an aromatic carboxylic acid, and thcJre:Eore, when the abovesaid mixed acids are rcacted with polyhydric alcohol, a more reactive aromatic carboxylic acid is far quickly incorporated into the ester chains, thereby resulting the polyester resin whose carboxyl groups capable of developing resinous acid value are mostly occupied ~y the abovesaid saturated alicyclic polycarboxYlic acid. When athe carboxyl groups capable of developing resinous acid value are occupied by such alicyclic carboxylic acid as having a lower dissociation degree in non - aqueous solvent, there would be a fatal disadvantage that the resulted resin is lacking in desired acidity and curability. Under the circumstances, the inventors, adopting the a~oresaid specific prepa -ration method, have succeeded in obtaining an ideal acid controlled modified polyester resin, in which 10 to 80 mole % o~ the acod components are composed of saturated alicyclic polycarboxylic acid, thereby improving the weather resistance o~ the resin, and 10 to 100 mole % of the carboxyl groups capable of developing resinous acid value are derived from aromatic polycarboxYlic acid having a large dissociation degree and acidity, thereby improving curability and weather resistance of the resin. However, even with this acid controlled modified polyester resin, there still remains a room for further improvement in pigment d1spersibilitY because of the nature of oil - free polyester resin . Therefore, in the present invention, a device has been made to provide an acid controlled modified amphoteric polyester resin through the addition, condensation or ester - exchange reaction between the abovesaid acid controlled modified polyester resin (A) and basic resin and/or basic compound (B).
In the present specification, the term " basic resin and/or basic compound " as used herein denotes a compound having in its molecule at least one functional group (e.g. hydroxyl, active alkoxy, carboxyl, ~ 2~

glycidyl, oxirane, alhylenei~ine, isocyarllJte and the like) capable of reacting with that of poly~ster(e.g. cster bondine, carbo~yl, hYdrox~l) and at least one functional group with nitrogen atom having a lone pair of electrons (e.g. - N < , isocyanate, alkyleneimine grouy and the like). Among the said compounds, comyaratively higher molecular weight compound is called as basic rcsin and comparatively lower ~olecular weight compound as basic compound.
Examples of basic resins to be reacted with acid controlled modiiied polyester resin (A) are urea resins, melamine resins, polyamide resins, urethane resins and the like and examples o~ basic compounds are comparatively lower molecular weight compounds o-f the abovesaid resins or hydroxylamine compounds as monoethanolamine, diethanolamine, aminopentanol, aminobenzyl alcohol, 2- dimethylaminoethanol and the like,amino acids as 3- dimethylaminobenzoic acid, 2- amino - isobutyric lS acid, 4 - amino - n - butyric acid, alkyleneimines as ethyleneimine and the like. The invention, however, cannot be limitted to these members only.
Since the acid controlled modi~ied polyester resins are a kind o-E
acidic resins having hydroxyl, carboxyl or the like, they can easily be converted to amphoteric resins with both acidic and basic propert -ies through addition, condensation or ester exchange reaction with basic resins and~or basic compounds. That is, a polyester resin~acidic resin) and a basic resin or basic compound can be reacted with each other through the iunctional groups possessed by themselves, as for example, hydroxyl group, carboxyl group, active alkoxy group and the like, or through the intervening crosslinking compound as diisocyanate, diglycidyl compound and the like.
In regard to the weight ratio of the reactants, i.e. acid controlled modified polyester resin (A) and basic rèsin and/or basic compound ~B), there is no particular limit on it providing re5ulting satisfactorY

%

addition, condensa-tion or es-ter exchange reaction therebetween.
It is, however, generally welcome to react 99.5~40 wt~ of the acid controlled modified polyester resin (A~ and 0.5~60 wt/% of the basic resin or 99.9~50 wt.% of the resin (A) and 0.1~50 wt.%
of the basic compound. As to the details of the preparation of an amphoteric resin by the reaction of such acidic resin and basic resin and/or basic compound, reference should be made to applicant's Japanese Patent Appllcatlon No. 120866/81 laid open as Japanese Patent Application Kokai No. 21468/83. The abovesaid acid controlled modified amphoteric polyester resin is, because of the preparation thereof, differing from the mere mixture of acidic polyester resin and basic resin, a reaction product of said two components and hence is excellent in stability, can never be separated to the respective raw material resins, do pos-sess amphoteric property and furthermore excellent in pigmentdispersion stabil~ty. In this resin, the said acidity and basic-ity should preferably be settled in the values hereinafter stated. However, since the acid controlled modified amphoteric polyester resin is insoluble in water, the inventors have devel-oped the original non-a~ueous analysis methods and evaluated the acidity and basicity of the amphoteric resin with them. That is, the amphoteric polyester resin is first dissolved in pyridine, subjected to a non-aqueous potentiometric titration wlth a titer of n-tetrabutyl ammonium hydroxide, and acidity of the resin is determined from the molar amounts of said reagent necessitated for the neutralization thereof. Next, the sample resin is dis-solved in acetic acid, subjected to a non-aqueous potentiometric titration with a titer of perchloric acid and the basicity of the resin is determined from the molar amounts of said reagent neces-sitated for the neutralization thereof. ~s the results of saidtests, the inventors have found that the a~ovesaid acid con-trolled modified amphoteric polyester resin should preferably have the acidity of 3.0~2.0 x 10-2 .

~L2 ~ L~

m mol/g solid, most prcferably ~.0 ~ 5.0 x 10-% m mol/g ~:olid, and the basicity of 1.0 ~ 5 x 10-3 m mol/e so1id, most; preferably 1.0 ~
1 x 10-2 m mol/g solid. This is because, with respect to acidity, ie it is less than the lower limit, there is a tendency that curing property and fil performance are decreased and if :it is more than the aforesaid upper limit, there is a tendency that water resistance and chemical resistance of the film are decreasecl.
In the present invention, the abovesaid acid controlled modi-fied amphoteric polyester resin is used together vith amino- formaldehYde resin etherified with monohydric alcohol having 1 to 4 carbon atoms, as, for example, melamine resin, guanamine resin, urea resin and the like. Ho~ever, for the object of the invention, particular preférence is given to melamine resin. And, the compounding ratio of said acid controlled modified amphoteric polyester resin and amino - formaldehYde resin may be in general freely selected,in terms of solid weight ratio, in a range of 60~ 90 parts by ~eight, preferably 70 ~ 80 parts by weight, of the former, and 40~ 10 parts by weight, preferably 30~ 20 parts by weight, of the latter. These figures were determined by repeating experiments.
Thus obtained resinous composition is,~hen used as solid color coating composition, characterized by having excellent weather resistance, gloss retention and deep color wa~ing property. Furthermore, since th modified polyester resin whose carboxyl groups capable of developing resinous acid value are controlled in kind, is amphoterized, it is like~ise e~cellent in compatibility with amino resin, pigment disper -sibility (dispersion speed, dispersion stability) and hence in finishing appearance as gloss and distinctness- of - image and curing property. Thus, the composition ia possessed of all characteristics of oil - free polyester coating composition and is free Erom the ~0 disadvantages thereof, and hence is very useful as coating for auto -~.. ............ .............. ........... . .. .

mobi].e bodies and the like.
The invention shall bc now mor~ ,fully ~xplaintd in the ~'ollowing Synthetic Examples,Examp1es and Comp~rati.ve E.7xamp].es. Un].c~:s othe~,i.s~
being staked, all parts are by wei,Kht.
Synthetic Example 1 ( acid control.led modif:ied amphoteric polyester resin solution I) Preparation of resinous composition containing acid controlled modif -ied polyester resin,50 mole % of acid component being hexahydrophth -alic anhydride and 75 mole % o-E the carboxyl groups capable o:E
developing resinous acid value o~ 8 being derived from isophthalic acid.
Composition of acid controlled modified polyester resin A
hexahydrophthalic anhydride 77.4 parts (0.5 mole~
isophthalic acid 66.98 (0.4 mole) adipic acid 14.62 (0.1 mole) trimethylol propane 25.61 neopentylglycol 52.67 1,6- hexanediol 55.40 292.18 parts 20 Calculation of isophthalic acid to be charged in later stage (bl mole) ~esigned resin.
resinous acid value N = 8.0 polyester resin weight W = 259.3 number of functional groups in isophthalic acid f = 2 reaction percentage of later charged isophthalic acid P = 90%
mole % of carboxyl groups derived from isophthalic acid in the total carboxyl groups capable of developing resi.nous acid val~le x - 75 Using the abovesai.d equation with these datas, bl - 0.139 mole (23.05 parts) was obt;ained.
Into a reaction tanh equipped with heating device, stirrer, reflux condenser, ~ater separa~or, ~ract:ional t;ower and thermameter, were placed the abovesaid 5iX mat~r.ials and the m.ixture was heated. At thi.s time, isophthalic acid was used in an amount of ~3.~3 parts (66.48 ~
23.05 = 43.43 parts). At the stage when the materials were ~used out, stirring was started and heating was continued until the tank temper -ature reached to 230C. However, from 160C to 230C, the temperature was raised at constant speed in 3 hours. The formed condensation water was distilled out of the system. When reached to 230C, tank mixture ~as maintained at the same temperature for 1 hour and then 5 parts of xylene ~refluxing solvent) were ~radually added and condensation reaction was further continued in the presence of said solvent.The reaction was stopped at the stage vhen the resinous acid value reached to 2.0 calculated by the equation:

M = 8.0 ( 1 - >

and the tank was allowed to coola to 100C to obtain a polyester prepolYmer A ~ ext, 23.05 parts (0.139 mole) of isophthalic acid were placed in and the tank temperature was raised to 210DC. At this timeJ rom l90DC to 210DC, said temperature was raised at a constant speed in 1 hour and the formed condensation was was distilled out of the system. When the tank temperature reached to 210C, the tank was maintained at the same temperature to continue the reaction. The said reaction was stopped at the stage when the resinous acid value reached to 8.0 and the reaction mixture was allowed to cool. After cooling, 106.1 parts o~ xylene were added to obtain an acid controlled modified . . .

~ 2 polyester resin solution A, the carboxyl ~roups capable of developin~
resinous acid value of said resi.n bein~ controlled in kind. This solution A had a non- volati].e content of 70.1% , varnish viscosity ( Gardner viscosity,at 25~C) of Z1 , and res:inous acid value of 8.1.
Using pyridine solutions of ~hus obtained polyester prepolYmer A - 1 and of acid controlled modified polyester res.;.n solution A, non -aqueous potentiometric titration was carried out with a titration reagent of n - tetrabuty]. ammorlium hydroxide (TBTM) and the titration curves were shown in Fig. 1.
As clearly known orm the drawing, the titration midpoint potential (R) of polyester prepolymer A - 1 t2) is 900 MV which agrees with the titration midpoint potential o-P polyester resin derived from an acid component of he%ahydrophthalic anhydride alone as shown in Table 1.
It was thus con~irmed that the carboxyl groups by which the resinous acid value of 2.0 of polyester prepolymer A - 1 was developed were ~ll derived from hexahydrophthalic anhydride used.
Ho~ever, in the tikration curve (1) of acid controlled modified poly -ester resin solution (A), there are 2 inflection points and the titration midpoint potentials (P,Q) are - 313 mV and - 905 mV,respec -2Q kivelyJwhich are well in accord with the titration midpoint potentialsof - 310 mV and - 400 mV for the polyester resins whose acid components are isopphthalic acid alone and hexahydrophthalic anhydride alone as shown in Table 1. Therefore, the carboxyl groups that are contributive to the development of resinous acid value of ~.1 of the acid controlled modified polyesker resin solution A are derived from both isophkhalic acid and hexahydrophthalic anhydride, the equivalenk ratio of khese acids being 75/25.
Thus, it was confirmed that the type o~ carboxyl groups capable o~
developing the resinous acid value were surely controlled as indicated under the " designed resin" by % = 75% .

Table A

Titration midpoint potentials for various carboxylic acids under the state capable of developi~g reslnous acid value ~PA .~.
hexahydrophthalic anhydride, Ad~ ..O adiplc acid, PAn ...
phthalic anhydride, IPHA ... isophthalic acid, TMAn ... trl~
mellitic anhy-drlde.

_____________________________________ ______________________ _~_ electrlcal potential (mv) 1o ___________~____~_______________________________________________ HHP~ ~400 ________________________________________________________________ AdA -390 ____ ___________________________________________________________ sebacic acid -420 ________________________________________________________________ PAn -290 ________________________________________________________________ _________.______________________________________________________ TMAn -240 ________________________________________________________________ To 100 parts of thus obtalned acid controlled modlfied polyester resin solution A, were added 6 parts of melamine resin (U-20 SE, a trademark of Mitsui Toatu K.K., non-volatile content 60%), and 7 parts of xylene and the mixture was heated and reacted at 90~100C until the viscosity ~by bubble viscometer) reached to Y. Thus obtained acid controlled modified amphoteric polyester resin solution I had an acidity of 0.18 m mol/g solid and basicity of 0.21 m mol/g solid and non-volatile content of 65.2%.

Synthetic Example 2 (acid controlled modlfied amphoteric polyester resin solution II) Repeating the same procedures as stated in Synthetic Example 1 with the materials shown in Table 1, was prepared an acid controlled modified polyester resin solution B having a non-volatile content of 69.6%, varni.sh viscosity of Z~zl and resinous - 15 - .

acld value oE 7.8.

To 100 parts of the said acid controlled modified polyester resin solution B, w~re added 7 parts of urea resin (UFR-65, a trademark of Mitsul Toatu K.K., non-volatile content more than 98%) and 11.5 parts of xylene, and the mixture was heated and reacted (heat-condensakion reaction) at 80~90C untll the viscosity ~by bubble viscometer) reached to Z.

Thus obtained acid controlled modified amphoteric polyester resin solution II had an acidity of 0.17 tm mole/g solid), a basicity of 0.53 (m mole/g solid), and a non-volatile conten~ of 65.1~.

Synthetic Example 3 (acid controlled modified amphoterlc polyester resin solution III) Repeating the same procedures as stated in ~ynthetic Example 1 with the materials shown in Table 1, was prepared an acid controlled modified polyester resin solution C, whose char-acteristics were non-volatile content 70.5, varnish viscosity Z2~z3 and resinous acid value 8.2.

To lO0 parts of thus obtained acid controlled modified polyester resin solution C, were added 10 parts of xylene, and 3.5 parts of isophorone diisocyanate ~manufactured by Huels) and the mixture was reacted at 80C until the reaction rate of iso-cyanate group reachad to 50% (determined by infrared spectrome-ter). Though the isophorone diisocyanate do possess both aliphatic and alicyclic isocyanate groups, since the aliphatic isocyanate group is much, as high as 10 times, reactive than the alicyclic isocyanate group, it is believed that at the stage when the reaction rate of isophorone diisocyanate reached to 50%, the aliphatic isocyanates have already been reacted with the hydroxyl groups of the polyester resin, but the alicyclic isocyanates ~26~

still remain unreacted. In the next place, while keeping the temperature at 80C, 1.0 part of monoethanolamine was added and reacted with said unreacted isocyanate yroups and after confirm-ing the completion of , : . .

- 16a -reaction o~ the whole isocyanate ~roup3 by in:Erared syec,~,rometer, the mixture was allo~ed to cool to obtai.n an acid eorltro11ed mod.ified amphoteric PolYester resin solutiorl III having an aidity of 0.19 ( m mole/g solid), a basicity of 0.11 ( m mole/g solid) and a non -volatile content o:E 69.6 %.Synthetic Exanlple 9 (acid controlled modified alnphoteric polyester resin solution IV) Repeating the procedures of Synthetic example 1 with the materia1s shown in Table 1, was prepared an acid controlled modified polyester resin solution D whose characteristics were non - volatile content 70.0 % , varnish viscosity Z 3 and resinous acid value 7.~.
To 100 parts of thus obtained acid controlled modified polyester resin solution D, were added 9.0 parts of xylene and 1.4 parts of isophorone diisocyanate (Huels) and the mixture was reacted at 70C until the isocyanate reaction rate of 50 % (determined by infrared spectometer).
While keeping the reac~ion ~emperat,ure a~ 70aC, 0.9 part of polyamide ~ Q ~oc~'4~S~
-- ~ resin ( Versamide 140,~ enkel Japan, amine value 370 ~ 900, viscosity 2~ 5 poise (75C)) and after confirming the co~plete reaction of the unreacted isocyanate groups and primary or secondary amino groups of Versamide 140, by means of infra - red spectrometer, the mixture was allowed to cool to obtain an acid controlled modified a~photeric polyester resin solution IY haviang an acidity of 0.18 m mole~g solid, a basicity of 0.28 m mole/g solid and a non - volatile content of 64.8 %.
Synthetic Examples 5 ~ 7 (modified polyester resin solutions V ~ VII) According to the prescriptions as ~iven in Table 1, modi:Eied polyester resin solutions V ~ VII ( the carboxyl groups capable of developing resinous acid value are not controlled in kind) were prepared by a conventional.esterification means of charging the whole materials in one time. The characteristics of these varnishes are shown in Table 1.

Synthetic Example 8 (po1yester resin solution VIJI) 537 Parts of coconut o:il, 218 parts oE trimethyloltthane and 0.3 part of lithium naphthenate were heated to 240~C and ester e~c,hange reaction was effectecl. Next, t74 parts of tr:imethylo]ethane, 176 parts of neopentylglycol, 523 parts of phthalic anhYdride ~nd 254 parts of isophthalic acid were added and the mi~tur~ was heated to 220 ~ 230DC
and dehydration reaction was e~fected at the same temperature until the resinous acid value o-f 5Ø After cooling, the mixtyre was diluted uith lO0 parts of m~ied hydrocarbon solvent(Solvesso lOO,~a~ YII~Y~}-~r ESS0 Standard) and 58 parts of ethyleneglycol monoethylether mono -acetate to obtain a polyester resin solution YIII having a viscosity (measured by bubble viscometer) of U ~ Y, a non - volatile content of 60 % and an acidity of 0.10 m mole/g solid.
Example l Using the acid controlled modified amphoteric polyester resin solution I obtained in Synthetic Example l and according to the prescription given belo~, a white colored dispersion paste was prepared. And then, a white primary colored coating composition was prepared following the solution ~ormulation hereinunder stated.
Table B
~formulation of white colored dispersion paste) Titanium white (Note l) oO parts acid controlled modified arnphoteric polyester resin solution I 25 Solvesso lO0 15 Dispersing agent (Note 2) 0.05 100. 05 (form1llation of white primarY colored coatin~ composition) white colored dispersion paste 100.05 acid conatrolled modified amphoteric polyester resln solution I ~2.0 parts Melamlne resin (Note 3) 21.0 n-butanol 5.0 trlethylamine ~ ~.
168~65 ~Note 1) Titanium R sN a trademark of Sakai Kagaku K.K.
tNote 2) 10% ~F-69 solution a trademark o~ Shinetsu Sllicon K.K.
(Note 3) Super Becakamine 16-50~ (non-volatile content 60%) a lo trademark of Dainioppon Ink K.K.

Acid controlled modifled amphoteric polyester resin I/melamine resin = 78/22 (solid ratio).

Thus obtained white primary colored coating composition was applied by flow coating method onto a glass plate and baked in a hot air dryer (140C) for 30 minutes.

Pigment dispersibility was evaluated by measuring 20 mirror gloss by Murakami type gloss meter GM-3M, of the coating.
Thus obtained result is shown in Table 2.

Examples 2 ~ 4 Red oxide, cyanine blue and anthraquinone red primary colored coating compositions were prepared with the acid con-trolled modified amphoterlc polyester resin solution I obtained in Synthetic Example 1, following the dispersion formulations and the solution formulations given in Tables C, D and E.
T~ble C
(formulation of red oxide dispersion paste) Red oxide ~Note 4) 50 parts acid controlled modified amphoteric polyester resin solution I 30 ~6~2 Solvesso 100 20 dispersing agent ~Q~i .

- l9a -100.()5 (formulation of red oxide primary colored coal;irlg composition) red oxide dispersion paste 100.05 parts acid controlled modified amphoteric polyester resin solution I 100.0 melamine resin 43. a n - butanol 7,0 triethylamine _ -?
250.75 10 acid controlled modified amphoteric polyester resin I /melamine resin - 77/23 ~ solid ratio) Table (formulation of cyanine blue dispersion paste) Cyanine blue (Note 5) 20 parts acid conatrolled modified amphoteric polyester resin solution I 56 Solvesso 100 30 dispersing agent 0.05 lOQ.05 (formulation of cyanine blue primary colored coating composition) cyanine blue dispersion paste 100.05 parts acid controlled modified amphoteric polyester resin solution I 40 melamine resin 29 n - butanol 5 triethYlamine 0.5 174.55 acid controlled modified amphotcric polyestcr resin I/melamine resin = 78/22 (solid ratio) I'able (formulation of anthraquinone rcd dispersion paste~
Anthraquinone red (Note 6)16 parts acid controlled modified amphoteric polyester resin solution 1 34 Solvesso 100 50 dispersing agent 0.05 100.05 (formulation of anthraquinone red primary colored coating composition) Anthraquinone red dispersion paste 100.05 parts acid controlled modified amphoteric polyester aresin solution I 37.0 melamine resin 24.0 n - butanol 5 0 triethylamine _ 0.5 166.55 acid controlled modiEied amphoteric polyester resin I/ melamine resin = 76/24 (solid ratio) (Note 9~ Taiyo Red Oxide 501, manufactured by Tone Sangyo K.K.
(Note 5) Fastgen blue 700- 3, manu-Eactured by Dainippon Ink K.~.
(Note 6) Chromophthal Red A3B, Ciba - ~eigy Thus obtained Red oxide, cyanine blue and anthraquinone red primary colored coating compositions were applied by flow coating method onto glass plates and baked as in Example 1. 20 Mirror gloss o:E the respective coating is shown in Table 2.
Examples 5 ~ ~
Wh1te colored,Red oxide colored,Cyanine blue colored and Anthraquinone red colored coating compositions were prepared ~ollowing the :Eormula -tion tables B^-E of Examples 1 ~ 9 but substituting acid controlled modified amphoteric polyester resin solution II Eor the resin solution I. These compositi.on.s each W.lS applied on a glass p:Late by :f].ow coating method and baked as in Example 1. 20" Mirror gloss of the respective coating is shown ;n Table 2.
Examples 9 ~ 12 White , Red oxide , Cyanine blue and Anthraquinone red primary colored coating compositions were Prepared by substituting acicl cont~olled modi~ied amphoteric polyester resin solution III obtained in Synthetic Example 3 for the resin solut;on I in the formulation tables B ~ E
of Examples 1 ~ 4. Thus obtained coating compositions were applied on glass plates and baked as in Example 1 and the measured 20 mirror glosses were shown in Table 2.
Examples 13 ~ 16 White , Red oxide , Cyanine blue and Anthraquinone red primary colored coating compositions were prepared by substituting acid controlled modified amphoteric polye~ter resin solution IV obtained in Synthetic Example 4 for the resin solution I in the formulati.on tables B ~ E
of Examples 1 ~ 4. Thus obtain0d coating compositions were applied on glass plates and baked as in Example 1 and the measured 20~ mirror ~losses were shown in Table 2.
Comparative Examples 1 ~ 16 White , Red oxide j Cyanine blue and Anthraquinone red primary colored coating compositions were prepared by substituting acid controlled modified amphoteric polyester resin solution V obtained in Synthetic Example 5, solution VI obtained in Synthetic Exalnple 6, solution VII
obtained in Synthetic Example 7 and solution YIII obtained in Synthe-tic E%ample 8 ior the resin solution I in the i`ormulation tables B ~
E of Examples 1 r_ 9. Thus obtained coating compositions were applied on glass plates and baked as in Example 1 and the Ineasured 20 mirror glosses were shown in Table 2.
Weather resistance, gel iraction and film periormance tests were then ~2~6~42 carried out with the fol1OwinLr :Eormulations.
Examples 17 ~ 19 Using each Oe the primary colored dispersion pastes based on acid controlled modified amphoteric po].yester resi.n .solution I obtained in examples 1 ~ 9 , white colored, red colored and blue colored coatin~
compositions were prepared as shown in the ~ollowing tables F, G and H, Table F
formulation of white colored composition ~hite dispersion paste 100 10 blue dispersion paste 0.02 acid controlled modified amphoteric polyester resin solution I 60 melamine resin 30 n - butanol 2 15 triethylamine 0.2 surface conditioner (Note 7) 0.4 192.8 Table G
formulation of red colored composition 20 red dispersion paste 62 red oxide d1spersion paste 35 white d1spersion paste 3 ac1d controlled modified amphoteric polyester resin solution I 115 25 melamine:resin 53 n - butanol ~ 5 triethylamine ~ 0.5 sur~ace conditioner 0.5 279.0 1'able ~l formulat;iorl o.~ blue colored composition blue dispersion paste 82 ~hite dispersion Paste 1 acid controlled modified amphoteric polyester resin solul;ion 1: 203 melamine resin 92 n - butanol 8 triethylamine 0.8 10 surface conditioner 0.8 ~ ~ ~ ~ Oq.6 `~ (Note 7) 50 % Modaflow solution,~Monsanto Chem. Co.
In each formulation, acid controlled modified amphoteric polyester resin I / melamine resin - 75 / 25 The abovesaid three coating compositions each was diluted with a mixed solvent of 10 parts of toluene, 20 parts of Solvesso 100, 50 parts of mixed hydrocarbon solvent (Solvesso 150, manufackured by Esso Standard ) and 20 parts of butyl acetate, to a viscosity of 23 seconds/ No. 4 Ford Cup (20C). Onto a Spc - 1 dull steel plate previously treated with zinc phosphate, subjected to a cationic electrodeposition and coated with an inter coat, the abovesaid diluted top coat composition was spray - coated and after standing for a defined period of time, the coating was baked at 140~C for 30 minutes.
Weather resistance, gel fraction and film performance tests were carried out with the respective coating and the kest resu'lts ~ere shown in Table 3.
Exa~ples 20 ~ 28 Using the primary colored dispersion ~)astes based on the acid controlled modified amphoteric polyester resin solutions II, III and - 2q -. . .

gL~6~L~ Z
IV obtained in Exanlples 5 ~ 16 and Pollow:ing the prescriptions showrl in tables ~, G and ~1 ( used acid contro]led modi~i.ed amphoteric poly -ester resin solutions II, II and IV), white colored, red colored and blue colored coating compositions were prepared. hs in Examples 17 ~
19, weather resistance, gel fractiorl and film performance tests were carried out and the test resul.ts were shown in Table 3.
Comparative Examples 17 ~ 28 Using the primary colored dispersion pastes based on the modified polyester resin solutions V, VI and VII and polyester resin so]ution VIII obtained in Comparative Examples 1 ~ 16 and following the prescriptiOns of tables F, G and 11 (replaced ~cid controlled modified amphoteric Polyester resin solution with each of the modified poly -ester resin solutions V, VI and VII and polyester resin solution VIII), ~hite colored, red colored and blue colored coating co~positions were lS prepared. As in Examples 17 ~ 19, weather resistance, gel :Eraction and film perEormance tests were carried out and the test results were shown in Table 3.

1able 1 (coinposition & varrlish characteristics) ~... .. .. _ ._ .__. .. _ ~
resin solution Syn. ex.l S~n. Ex 2 ~yn. ~x.3 ______ ~ ____ ____ __ _ __ ,__ __~ __ __,__ composition of polyester prepolym~r hexahydro phthalic anhyd. 77.4~0.6) 71.98(0.465) 75.85~0.490) _ ._ ....... . _ __ .... ..._ _ _ isophthalic acid 43.~3(0.261) 66.48(0.4) 66~48(0.4) .. __ ..... .. _ .. .. _ . ____ _ ___ _ _. _ adipic acid 14.62(0.1) 14.62(0.1) 14.62(0.1) ,... ._ trimethylol propane 25.61 25.61 25.61 ... _ . .... ~ . . .~ ~
neopentylglycol 52.67 52.67 52.67 . _ 1,6- hexanediol 55.40 55.40 55.40 _ _ _ _ later charged polycarboxylic acid (B? and amour!ts phthalic anhyd. 5.19(0.035) . _ ___ ___ . . . _~
isophthalic acid 23.05(0.139) .
trimellitic anhyd. _ _ 1.97(0.010) . __ . _ . . __ figures taken account in the preparation of designated_t esin polyester resin weight W 259.30 259.07 259.72 ... .. _ resinous acid value N 8.0 8.0 8.0 .
functional group number f 2 2 2 of later charged (B) ..
reaction % of later 90 60 40 charged (B) _ mole % (x) of B in the carboxyl groups capable of 75 75 S0 develop. resinous acid value _ .. ~ __ .. ...
Resin solution I II III
. . . .. ~_ basic resin or compound melamine R. urea Resin IPDI,ETA
. . i_ _ . .. __ .... .. ~ ....... . ._ varnish characteristics acidity (0mol/g solid) 0.18 0.17 O.t9 .. ...... __ basicity(mmol/g solid) 0.21 0.53 0.11 non - vol. (% ) 65.2 65.1 64.6 . . -- .. ......... .

x l`able I (contirlued) . _ --resin solution Syn. Ex.~ Syn. Ex.5 Syn. Ex.6 I) V VI
~ _,__ __ _ _.____ composition of_ _Iyesl~er p~oLynler hexahydro phthalic anhyd. 30.9f;(0.2) 77.9 (0,5) 30.96(0.2 ... .. ~ , , . ._ __ isophthalic acid 63.48(0.382) 66.~8(0.4) 116.34(0.7~
__ ... _ __ .__ _ _ __ _,____ __ adipic acid 14.62(0.1) 1~.62(0.1) 14.62(0.1) ,_ trimethylol propane 25.17 25.61 25.17 . __ .... ___ _ . . _ neopentylglycol 70.32 52.67 70.32 .. .. ~ . .
1,6- hexanediol 60.90 55.90 60.90 . .. .__.. . ___ _ . .. . _ ..
later charged pol~carboxylic acid (B) and amounts _ .
phthalic anhyd.
_ _ . . _ isophthalic acid 52.86(0.318) trimellitic anhyd.
_ figures taken account in the preparation of designated resin polyester resin ~eight W 25~.88 259.3 254.88 ._ resinous acid value N 8.0 8.0 20.0 . . . .... . .
functional group number f 2 of later charged (B) reaction % of later 95 charged (B) _ mole % (x) of B in the carboxyl groups capable of 87.5 develop. resinous acid value Resin solution IV
basic resin or compoundIPDI,polyami de _~ . .
varnish characteristics acidity (mmol/g solid) 0.18 0.20 0.55 basicity(mmol/g solid) 0.28 0.006 0.005 non - vol. (%) 64.8 _ 69.6 ... . ..
. .

l`able 1 (cont;irlur,cl) __ resill solution ~yn. ~ 7 ~yn. ~x.8 Vll VIII
_ ~ , .. , .. .,, ., _.,.. ......... ... ,.. , .. , ,,. ,.. . , .. _ ., ~
composition_of pv1yc.s~;-r_pltp(l1yln~r coconut o;l 573 hexahydro phthalic antlyd.lt)8.3f;(0.7) trimet;hy1O1ethane 218 isophthalic acid _ _ __ _ _ Li naphthenate 0 3 adipic acid 99.86(0.3) phkha. anhyd . 523 trimethylol propane ~6.70 isophth. acid 254 __ . ___ .
neopentylglycol 30.82 trimethylolethane 17~
1,6- hexanediol 64.83 neopentylglycol 176 , _ _ later charged polycarboxylic acid_~) and amounts ~hthalic anhyd.
I_ isophthalic acid _ trinnellitic anhyd. __ _ _ figures tahen account in the preparation of c signated resin polyester resin weight W 259.75 175.7 __ _ resinous acid value N 20.0 5.0 functional group number f of later charged (B) reaction % of later charged (B) mole % (x) of B in the carboxyl groups capable of develop. resinous acid value , _ __ Resin solution _ _ _ basic resin or compoundIPDI,polyami varnish characteristics acidity (mmol~g solid)0.54 0.10 basicity(mmol/g solid)0.006 0.006 non - vol. (% ) 70.3 60.0 1~ 2 I' bl 2 ~J . (~
evaluation o~ dispersiorl property ¢xample _ __ _ _ ~ . _ __: _~ __ ___ 1 - 2 3 ~ 5 6 7 8 _ _ _ ___ resin solution I I I I IIII II II
_ _ .__,_ __ ~ _ ___ Prim. color coat. W R - I Bu R - 2 W R - 1 Bu R - 2 _ 20D mirror gloss 88 75 ~ 6 81 L 84 74 83 80 _ Example _ _ esin solution III III III III IV IV IV IV
__ rim. color coat. W R - 1 Bu R- 2 W R - 1 Bu R - 2 _ .
20 mirror gloss 81 68 81 73 83 70 82 75 W = white primarY color R - 1 = red oxide primary color Bu = cyanine blue primary color R - 2- anthraquinone red primary color .. ...

, . , ~LZ66~4Z
1able 2 (cont;irlued) Comparative Example 1 ~2 -- L3 __ ~ 6 7 - 8 resin solution V V V V VI YI VI VI
Prim. color coat. W R - 1 Bu R - 2 W R - l Bu R - 2 20 mirror gloss 76 40 75 43 73 41 75 40 Comparative Example ll 1Z l3 - 14 1 15 -16-.
resin solution VII VII VII VII VIII VITI VIII VIII
. . __ Prim. color coat. W R - l Bu R - 2 W R - 1 Bu R - 2 20 mirror gloss 76 45 76 42 78 4g 76 50 W = white primary color R - l= red oxide primary color Bu = cyanine blue primary color R - 2= anthraquinone red primary color ;

:
, ~
:

~ - 30 -:

I'ablc 3 weather resistance, gel fractiorl, Eilm perevrmance test resu~ts _ ~xamplè
__ _ _ 1 17 _ _ _ _ _ _ __ _ _ 21 22 resin solution I I :C :~I rI II
_. ____._. ._ _ . ._ _. _ _ _. .~ . .. _ _ _.__ _ _ coat. color whit;~ red bllle whil;e red blue finish. appearance (gloss, thick.) * 1 ~ O ~ O O
.. .... ___._ ._ _ _ _ ___ _ _ __ _ 60 mirror gloss~ 2 95 93 94 95 94 93 pencil hardness 11 H H H _ H H
impact strength(cm) DuPont type ~ - 1/2l~ 35 40 90 35 ¦ 35 35 500 g _ _ acid resitance * 3 no abnormality ... ........... ... __ _ . .... ___ alkali resist. * 4 no abnormarity ... _ interlaminar adhesion * 5 0/100 _0/100 0/100 0/100 0/100 0/100 accelerated weather resis.
QUV 300 hrs. 60 gloss retention 93 94 92 91 92 92 QUV 600 hrs. 60 gloss retention 85 89 83 82 85 84 outdoor exposure(Okina~a) 60 gloss after 18 months 90 88 87 87 85 88 ~axing reist. after 18 months * 6 _ O O O O
gel fraction * 7 baked at 120C 88 87 88 90 91 90 baked at 140~C 94 94 93 95 -- 94 94 . .

~;6~LZ
'I'able 3 (contirlued) _ . Example , ., ._ 25 _ _ 27 2 resin solution ~II rIT II'~ IY IV IV
_ __ _ _. , ,._. . _ ; . .. .. .... ,., , __ ~ __, _ _ _____ coat. color ¦whLte _,re(l bllJe white red blue Einish. appearance (gloss, thick.) * 1 ~ O ~ ~ O
______.____,_ ___ ~ __ _._ 60 mirror gloss~k2 99 93 92 94 92 89 pencil hardness __ H ~l H H H H
impact strength(cm) DuPont type ~ = 1/2l/35 35 40 35 35 35 500 ~ ~ _ _ _ acid resitance * 3 no abnormality __, . _ alkali resist. * 9 no abnormarity __ _ __ . ____ ___ interlaminar adhesion * 5 0/100 0/100 0/100 0/100 O/100 0/100 accelerated weat,her resis, 1-- - - ~~ ~- -----~UV 300 hrs. 60 gloss retention 9~ 91 92 91 93 90 QUV 600 hrs. 60 gloss retention 86 83 88 86 84 85 outdoor exposure(Okinawa) _ _ , 60 gloss after 18 months 86 83 87 88 86 85 _ .
waxing reist. after 18 months * 6 _ O O _ O O
gel ~raction * 7 baked at 120C 91 90 91 90 89 89 baked at 140~ 96 95 95 . 9-4---- 95 94 ~64i~
Table 3 (cont,irlued) . . _ __ _ _ Comparative example _ _ i8 . _ _ 2~21 22 ... __ ___ _.. _., .. .... ... .__ . . _.. ,__ ._.. __. _ . ,.. ~ ____ l resin solution _ V _ _V__ _ V _ _~ VI VI
coat. color w~lLte red blue white red blue finish. appearance (gloss thick.) * 1 ¦ _ O X _ _ _ X O
60D mirror gloss ~ 2 91 80 90 91 78 92 . . . ~ .. __ .....
pencil hardness FH FH FH H F F
. .... .. ~ __ _ impact strength(cm) DuPont type ~ = 1/2/r 35 3030 30 30 30 500 g _ _ _ _ _ _ _ acid resitance * 3 a c c c c c . . _ ____ . , . .. .... _ _ ___ , alkali resist. * 9 b a a b a a interlaoindr . _ _ . . . .
adhesion ~ 5 0/100 0/100 0/100 0/1000/100 0/100 accelerated weather resis.
QUV 300 hrs. 60D gloss retention 80 B2 79 82 79 77 QUV 600 hrs. 60D gloss _ _ retention 73 76 79 77 70 74 outdoor exposure(Okinawaj _____ _ _ _ _ ___ _ __ 60 gloss aiter 18 months 76 75 76 78 71 73 - _. ._ . _._ waxing reist. after 18 months * 6 _ _ ~ O O O
gel fraction * 7 baked at 120C 80 79 80 83 84 82 baked at 140C 91 91 88 92 90 91 a .. so~e discolor b.. discolor, blister c.. no abnormality ~L2~ 2 Table 3 (cont;.nued) Comparative ~xar~ple _ _ _ - _ 25 f _ ._ 27 2g ~ . _ . _ ., _ _. _,_ . . .__,. _ _ _ . ~
resin solution VIr VII VtT VII~ ~IC~ VILI
~ . .. . .. _ . ... _.. _ .-- . . ~ . . _.. _.,_ _ . _ coat. color wh:i~e red blue wh:Lte red blue flrlish. appearance (gloss, thick ) * 1 _ ~ _ X O ~ O
60 mirror gloss * 2 91 73 91 93 85 88 pencil hardness Fll Fll FH IIB IIBHB
ialpact strength(cm) DuPont type cP = 1/2~l 35 30 35 35 40 40 500 g _ ~ _ _ acid resitance * 3 a c c a c c _ _ _ .
alkali resist. * 4 b a a b a a interlaminar _ _ _ adhesion * 5 0/100 0/100 0/100 0/100 0/100 0/100 accelerated weather resis.
~UV 300 hrs. 60D gloss retention 81 80 80 34 73 64 QUV 600 hrs. 60 gloss retention 73 74 73 13 51 46 outdoor exposure(Okinawa) 60 gloss after 18 months 73 71 75 66 54 62 waxing reist. a-~ter 18 months * 6 O O X
gel fraction * 7 baked at 120C 83 80 82 88 87 89 baked at 140C 90 91 93 95 93 94 . . . _ a .. some discolor b.. discolor, blister c.. no abnormality ~6G~4~

Test methods and evaLuatiorl sl;arltlards (NoLc 1) ~inis~ appc<lrallcc :
Finishing appeararl(e was ev~luated by v:isual observatiorl of gloss and thickness on the basis oE t~lo Collowirl~ oritcria :
~ .... very Koocl O .... g~od .................. sligtlt;ly in:Eerior X .... no good (Note 2) 60 (mirror) gloss 60 reflectance was measured by usiang Murakami type glossmeter (Note 3) Acid resistance 5 ml of N/10 H2 SO ~ was dropped in a glass cyclinder (inner diam.
of 38 mDI, height of 15 loln) placed on the coating. After standing for 24 hours at 20C, the coating was washed with water and any occurence o~ wrinkles, blisters and coLor changes were observed.
(Note 4) Alkali resistance 5 ml of N~10 NaOH was dropped in a glass cyclinder as used in the abovesaid test, and after standing in a drier (55C) for 4 hours and subsequently washing with water, any occurence of wrinkles, blisters and color changes were observed.
(Note 5) Interlaminar adhesion Onto a substrate, the coating composition obtained in each Example was applied and baked at 160C for 30 minutes. Therea-Pter, the same coating composition was spray ~ coated as a top coat and baked at 140 C Eor 30 minutes (2 coats with the same coating composition).
Thereafter, cros- cuts with 2 mm width cut were made with a razer and peel test was carried out with a cellophalle tape. The result was evaluated by the number of peeled out coatings in 2 cm square each.
(Note 6~ Waxing resistance h small quantity ot car wax (Soft ~9 seln:i kneaded type, manuf.Jctured by Nitto C~lelll. Co.) was taken on a white lirlerl and rubbed aKainst the coating intensely w:ith khe foref;rl~er 1U ~imes back and forth over a distance of 10 cln. An excess alllotlnt of wax reMairled on the coatin~
was wiped out ~ith a :eresll linerl cLoth and the coating surface was visual]y observed. The r-es~ilt was evaluated from the extent of gloss down, abrasions and coloring of ~hite linen cloth.
O... no gloss down and abrasions on the coating and no coloring of white linen ~ ... slight gloss down and abrasions, and some coloring of white Linen X... considerable gloss down and abrasions, and marked coloring white linen (Note 7) Gel fraction Sample specimen of baked coating was subiected to solvent extraction with acetoneJmethanol= 1/1 (wei~ht), using Soxhlet -extractor, at 70C for 5 hours, and the extract was dried at 120C for 30 minutes in a drier, and then cooled in a decicator. The extract was weighed and gel fraction was calculated from said result.
Synthetic Example 9 (acid controlled modified amphoteric polyester resin solution IX) An acid controlled modifed polyester resin solution E ~as prepared by using the same method as stated in Synthetic Example 1 and ~ollowing the prescription given in Table 4.The characteristics of thus obtained varnish were as follows: non - volatile content 70.2% , varnish viscosity Y - Z and resinous acid value 7.9 To 100 parts of thus obtained acid controlled modified polyester resin solution E, 6 parts of melamine resin U - 20 SE (non - volatile content 60 %, manufactured by Mitui Toatu K.K.) and the mixture ~as reacted as in Synthetic Example 1 to obtain an acid controlled modified ~2~;6142 amphoteric polyester resirl solution IX having the characteristics of varnish viscosity Z2, acidity 0.20 (m mol/g solid~, basicity 0.21 (m mol/g solid) and non - volatile content 70.0 %.
Synthetic Example lO ( acid controlled modified amphoteric polyester resin X) An acid controlled modi:Eied polyester re.sin solution F ~as prepared by using the same Illethod as stated in Synthetic Example 1 and follow -ing the prescription shown in Table 9 . This varnish had the characteristics of non - volatile content 70.5 % , varnish ViscositY
W - X and resinous acid value 7.8. To 100 parts of thus obtained acid conatrolled modified polYester resin solution ~, 6 parts of melamine resin U - 20SE (non- volatile content 60% , manufactured by Mitui Toatu K.K.) were added and reacted as in Synthetic ExamPle 1. An acid controlled modiied anlphoteric polyester resin solution X having the characteristics of varnish v.iscosity Z, acidity 0.19 ~m mol/g solid), basicity 0.21 ( m mol/g solid) and non- volatile content 70.1 % was obtained.
Examples 29 ~ 36 White, red oxmde, cyanine blue and anthraquinone primary colored coating compos1t~ons were prepared by following the EormuLations given in tab:1~es B ~ ~E of~Example5 1 ~ 9 , but substitutmng the acid controlled mod1~med amphoterlc polyester resin solutions IX and X
obtained in S~yn~thetic Examples 9 and 10 for the re9in solution I.
These compositions~eas ~as applied on a glass plate by flow coating method and baked as ln:Example l and the 20 mirror gloss of the baked coat1ng wa:s shown in Table 5, respectively.
Examples~ 37~ ~ ~2 Using:~the primarY colored d1spersion pastes based on the acid controlled modif1ed:auphoteric polyester resin solutions IX and X
obta1ned 1n Examples 29 ~ 36 and following the prescriptions given ~ 37 -~266~AZ
in T~bales F, G ancl ll ( used IX arld X as acid control].ed modiied ~ephoteric polyester resi.rl solution), white colored, red colored and blue colored coating compositi.on.s were prepared. For the respective composition, weather resistance, gel :raction and :~ilm per~ormance were tested as in ~xanlp:Les 17 ~~ 19 and the results obtained were showin in Table 6.
The test methods and evaluati.on standards are as stated hereinbefore.
Possibility of industrial use As stated hereinabove, the present resinous composition can afford, wherl used as resinous vehicle in a clear or colored coating composit-tion, excellent coating in respect o-f weather resistance, mechanical properties and inte-rlaninar adhesion, and especially curing propertY , pigment dispersibi.li.ty and colnpatibility with melamine resin, and hence is very useful as a top coat for automobile bodies and the like.

:

~: ~

; :: ~:
:: :: :
~: -~LZ~;6 'lab:le ~

Example _ ~ __ _ _ . ____.___ _ .. _ _ _. . __ _ . .... _____ ~. __ ~
resin solution ~ F
. _ ._ ____.___. _____________~___ ~ _ ___ CocoTlut; oil 30.11 117.9 _ . . _._ __~ _ hexahydro phtha. anhyd. 96.44 (0.3) 46.44 (0.3) ... _ _ .____ ___ _ isophthalic acid 91.11 (0.55) 83.1(0.5) trinlethylolpropane 28.96 70.51 . _ _ __ . . _ _ . .__ neopentylglycol 82.39 ~3.8g .... _ _ _. _ . ___ _ _ _ I
1l6- hexanediol 17.50 9 08 . _ __ _ . ._ later charged acid isophthalic acid isophthalic acid (B) and amounts thereof25.23 (0.15) 33.24 (0.Z) . . .. _ .
ures deterolined at _ the preparation of resin polyester resin ueight W 283.9 370.5 ~ _. . . _ ___ __ _ resinous acid value N 8.0 8.0 . . __ _ . . _ . ... .
number o functional groups f of later charged (B) _ __ 2 _ _ _ 2 reaction % thereo 90.0 90.0 _ _ .
mole % x of (B) occupied in the total carboxyl groups that 75 75 develope resinous acid value _ ..... _ resin solution IX X
~ _ __.__ _ ___ basic res:in or compound melamine resin melamine resin __ . _ , .
varnish characteristics acidity(m mol/g solid) 0.20 0.19 basicity(m mol/g solid) 0.21 0.21 _ _ _ . . _ . .
NY content % 70.0 70.1 ___ . _ ._.~ _ . .__ __ .-- _ _ _._A. . __ _ ______ __ ( ) indicates mole .

~,Z6G~4Z
Table 5 Example No. Exalnple 29 30 ~' ~-31 - 32 33 -3~ 35 3 _ _ ____ ____ _,. _ _ resin solution IX IX :[X IX X X X X
_ __ ____- ___ _ __ prinl. color coat. W R - 1 Bu _ ~ - 2 W R - 1 Bu R - Z
20 mirror gloss B7 7586 82 88 7~ 86 83 Table 6 Example No. 37 38 39 ¦ 40 41 42 resin solution _ ___ ~ IX _ _ r_ x coating color W R Bu W R Eu finishing appearance * 1 O ~ _ I ~
60" mirror gloss * ~ 95 93~ 95 96 94 95 pencil hardness FH FH FH HB H~_ HB
_ __ _ impact strength (cln) DuPont type ~ - I/2" 500~ 3535 1 35 40 1 40 90 acid resistance * 3 no abnormality _,_____ alkali resistarlce * 9 no abnormality interlaminar adhesio~ * 5 ~ 0 / 10 accelerated weather resist. ~ _ _ 60 gIoss retention a~ter QUV 300 hours ~ ; ~ 92~ 93 91 92 90 91 _ 60 glos~s~retentiorl after ~
QUV 600 hours ~ ~ 89 88 ~ 8385 83 &2 outdoor e~posure (Ohillawa3 60 gloss~a~ter l~8~nonths~ 89 87 87 87 85 86 waxing `resistance a~ter 18 month~s~ * 6 ~ ~ ~- O O O O
:
gel fr~action * 7 ~ ~ I ~
~baking te~np. 120C~ __ 88 86 87 89 88 89 bahin8~te-p. l40~C~ ~ ~ 9 93 ~ 95 93

Claims (7)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A coating use resinous composition comprising 60?90% by weight of amphoteric polyester resin obtained by the reaction of polyester resin (A) comprising alcohol and acid components, 10?80 mole% of the acid components being a saturated alicyclic polycarboxylic acid and 10?100 mole% of the carboxyl groups capable of developing a resinous acid value, said carboxyl groups being derived from a polycar-boxylic acid showing a titration midpoint potential in a non-aqueous potentiometric titration, under a state capable of developing a resinous acid value, of more than -350mV, and (B) a member selected from the group consisting of a basic resin and a basic compound or mixtures thereof, and 40 ?10% by weight of an amino-formaldehyde resin etherified with a monohydric alcohol having 1 to 4 carbon atoms, said basic resin and basic compound both containing in its molecule at least one functional group capable of reacting with the ester and at least one functional group with a nitrogen atom having a lone pair of electrons.

2. The composition according to claim 1 wherein the amphoteric polyester resin has an acidity of 2.0 x 10-2?, 3.0 m mol/g solid and a basicity of 1.0 x 10-2? 1.0 m mol/g solid.

3. The composition according to claim 1 or 2 wherein the amphoteric polyester resin is the resin obtained by the reaction of 99.5?40 wt%, in terms of resinous solid amounts, of (A) resin and 0.5?60 wt% of (B) resin or 99.9?
50 wt% of (A) resin and 0.1?50 wt% of (B) basic compound.

4. The composition according to claim 1 wherein the polycarboxylic acid showing a titration midpoint poten-tial in a non-aqueous potentiometric titration, under a state capable of developing a resinous acid value of more than -350 mV, is selected from the group consisting of phthalic anhydride, isophthalic acid, terephthalic acid, trimellitic anhydride and pyromellitic anhydride.

5. The composition according to claim 4 in which the alicyclic polycarboxylic acid in the polyester (A) is selected from the group consisting of 1,1-cyclohexane dicar-boxylic acid, hexahydrophthalic acid and its anhydride, 1,3-cyclohexane dicarboxylic acid, 1,4-cyclohexane dicarboxylic acid, methylhexahydrophthalic acid and its anhydride, hexa-hydrotrimellitic acid and its anhydride, and hexahydro-2-methyl-trimellitic acid and its anhydride.

6. The composition according to claim 1 wherein the polyester is produced by the reaction of a polyol selec-ted from the group consisting of ethyleneglycol, diethylene-glycol, propyleneglycol, neopentylglycol, 1,2-butylenegly-col, 1,3-butyleneglycol, 2,3-butyleneglycol, 1,4-butylene-glycol, 1,6-hexanediol, 1,5-pentanediol, 2,5-hexanediol, trimethylolethane, trimethylolpropane, glycerin, pentaery thritol, diglycerin, sorbitol, and 1,4-cyclohexane dimeth-anol, an alicycllc acid selec-ted from the group consisting of 1,1-cyclohexane dicarboxylic acid, hexahydrophthalic acid and its anhydride, 1,3-cyclohexane dicarboxylic acid, 1,4-cyclohexane dicarboxylic acid, methylhexahydrophthalic acid and its anhydride, hexahydrotrimellitic acid and its anhydride, and hexahydro-2-methyl-trimellitic acid and its anhydride, and a polycarboxylic acid showing a titration midpoint potential in a non-aqueous potentiometric titrations, under a state capable of developing resinous acid value of more than -350 mV, selected from the group consis-ting of phthallc anhydride, isophthalic acid, terephthalic acid, trimellitlc anhydrlde, and pyromellitic anhydride.

7. The composition according to claim 6 wherein member (B) is selected from the group consisting of urea resins, melamine resins, polyamide resins, urethane resins, monoethanolamine, diethanolamine, aminopentanol, aminobenzyl alcohol, 2-dimethylaminoethanol, 3-dimethylaminobenzoic acid, 2-aminoisobutyric acid, 4-amino-n-butyric acid, and ethyleneimine.