Low molecular weight hydroxy functional polyesters for coatings

The polyester composition of this invention comprises a polyester oligomer having a number average molecular weight of from about 650 to about 950, a weight average molecular weight of from about 950 to about 1900, and a polydispersity of from about 1.45 to about 2. The hydroxyl value is from about 150 to about 275, and the acid number is less than about 7. Substantially all of the hydroxy groups are primary and from 0 to about 5% of the hydroxy groups are present as pendant hydroxy-alkyl groups. The polyester is formed by a two-stage reaction of monomers consisting of carboxylic anhydrides having from 4 to 34 carbon atoms and polyols having from 2 to 20 carbon atoms. From about 10 to about 50% by weight of the monomers are anhydrides having the formula: ##STR1## where R.sup.1 is a non-aromatic hydrocarbon radical having from 6 to 30 carbon atoms, R.sup.2 is hydrogen or a non-aromatic hydrocarbon radical having from 1 to 8 carbon atoms. The total number of carbon atoms in R.sup.1 and R.sup.2 is from 8 to 30 carbon atoms. The polyester in conjunction with a hydroxyl-reactive curative provides a coating composition.

The present invention relates to low molecular weight, hydroxyl-functional 
polyesters wherein greater than 95% of the hydroxy groups are 
chain-terminating and the remainder are in pendant hydroxyalkyl groups. 
The polyesters of this invention have a number average molecular weight 
(M.sub.n) of from about 650 to about 950, a weight average molecular 
weight (M.sub.w) of from about 950 to about 1900, and a polydispersity of 
from about 1.45 to about 2. The invention also relates to a method for 
preparing such oligomeric polyesters and leaving about 2.5% or less by 
weight of residual monomers. The polyesters can be formulated into coating 
polymers with appropriate hydroxyl-reactive cross-linking agents. More 
particularly, the invention is directed to such polyesters having large 
hydrocarbon side chains which act to reduce viscosity of coating 
compositions and provide coatings with enhanced flexibility. 
BACKGROUND OF THE INVENTION 
U.S. Pat. Nos. 4,403,093 and 4,659,778, the teachings of each of which are 
incorporated herein by reference, teach stepwise growth of polyesters. In 
stepwise growth, each step of chain elongation is carried out 
substantially to completion prior to a further polymer chain elongation 
step. Low molecular weight polyesters produced by such stepwise chain 
elongation are formulated with appropriate cross-linking agents to form 
coating compositions. 
Substantially linear, low molecular weight, low dispersity, 
hydroxyl-functional polyesters in which less than 5% of the hydroxyl 
groups are pendant from the chains are made by end-capping 
carboxyl-terminated polyesters with mono-oxirane compounds according to 
co-pending, commonly assigned patent application Ser. No. 08/883,984 which 
was filed on Jun. 27, 1997. 
Of particular interest herein are hydroxyl functional, low-molecular weight 
polyesters formed by reacting a carboxylic anhydride with an excess of a 
multi-functional alcohol (polyol) on an equivalents basis so as to provide 
a hydroxyl-terminated polymer chain without the need of reacting a 
carboxyl-terminated chain with an oxirane-containing compound. While the 
polyester of this invention has substantial terminal 
hydroxyl-functionality, it contains substantially no pendant secondary 
hydroxyl functionality and a minimal amount of pendant primary hydroxyl 
functionality in the form of hydroxy-alkyl groups which survive from the 
small amount of triols used in the formation of the polyesters. 
High solids coating compositions with low VOCs may be formulated from such 
polyesters having low viscosities produced by the method of this 
invention. Surprisingly, coatings formed from the polyesters of the 
present invention provide cured coating compositions with enhanced 
flexibility. Improved pigment wetting is observed through the use of such 
polyesters in the coating in accordance with the invention. 
Above-referenced U.S. Pat. No. 4,659,778 to Williams et al describes a 
polyester formed by reacting an anhydride with a diol so as to obtain a 
half-ester and subsequently reacting the half ester with a di-functional 
oxirane compound so as to form a hydroxyl-terminated polyester. The 
di-functional oxirane becomes incorporated internally within the polyester 
chain, providing two hydroxyl groups which are pendent from the chain, 
i.e., are non-terminal hydroxyl groups. The polyesters are cross-linked to 
form coatings. For the purposes of the present invention, where a highly 
flexible coating is desired, a large proportion of pendant hydroxyl 
groups, whether primary or secondary, are undesirable because that would 
result in high cross-link density which reduces flexibility of the cured 
coating. 
The prior art teaches against the use of high molecular weight anhydrides, 
such as dodecenylsuccinic anhydride or octadecenylsuccinic anhydride 
because of a perceived harm to the physical properties of coatings derived 
from polyesters made from it. The coatings are said to be too soft. 
Applicants, herein, find that such high molecular weight anhydrides when 
incorporated in short chain polyesters of low polydispersity provide 
coating compositions with low viscosity, excellent pigment wetting and 
provide coating films with high flexibility. 
SUMMARY OF THE INVENTION 
It is an object of this invention, therefore, to provide a novel method for 
preparing a substantially linear, hydroxyl-functional, low molecular 
weight polyesters having a narrow polydispersity. 
It is another object of this invention to provide such substantially 
linear, hydroxyl-functional, low molecular weight polyesters having a 
narrow polydispersity. 
It is another object of this invention to provide hydroxyl-functional, low 
molecular weight polyester compositions having less than 2.5% residual 
monomer content by weight. 
It is another object of this invention to provide hydroxyl-functional 
polyester-based coating compositions having a high solids content and a 
low viscosity. 
It is another object of this invention to provide hydroxyl-functional 
polyester-based coating compositions having a low volatile organic content 
(i.e., VOC). 
It is another object of this invention to provide hydroxyl-functional 
polyester-based coating compositions by which thicker film builds without 
blistering are attainable. 
It is another object of this invention to provide hydroxyl-functional 
polyester-based coating compositions having better flow properties for 
easier application. 
It is another object of this invention to provide hydroxyl-functional 
polyester-based coatings which have better gloss and depth of image (DOI). 
In accordance with the invention, there is provided a polyester composition 
having a number average molecular weight (M.sub.n) of from about 650 to 
about 950, a weight average molecular weight (M.sub.w) of from about 950 
to about 1900, a polydispersity of from about 1.45 to about 2, a hydroxyl 
functionality of between 2 and 3, a hydroxyl value of from about 150 to 
about 275, and an acid number less than 7. Of the hydroxyl groups in the 
polyester, all are primary and less than about 5% are pendant from the 
chain as hydroxy-alkyl groups. Residual monomers amount to a maximum of 
about 2.5% by weight of the polyester composition. 
The coating composition of this invention is prepared by mixing the 
polyester of this invention, alone or in admixture with other polyesters, 
with an appropriate hydroxyl-reactive cross-linking agent, such as an 
aminoplast resin or a blocked isocyanate.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
For the purposes of this invention, substantially is a term used herein to 
mean that the difference between being largely but not wholly that which 
is specified is so small that it is inconsequential. 
Polyester compositions in accordance with the invention are formed by 
mixing an anhydride of a dicarboxylic acid having from 5 to 34 carbon 
atoms and a polyol having from 2 to 20 carbon atoms at a ratio of from 
about 1:1.3 to about 1:1.9 on a molar basis and initiating a 
polycondensation reaction at a temperature of from about 110.degree. to 
about 120.degree. C. to ensure that all the anhydride has reacted with a 
polyol before the resultant half-esters are oligomerized at a temperature 
of from about 220.degree. to about 230.degree. C. to produce 
hydroxyl-terminated polyesters of low molecular weight and low 
polydispersity, which preferably is from about 1.6 to about 1.8. In a 
preferred method of this invention, the molar ratio of anhydride to polyol 
is in the range of from about 1:1.5 to about 1:1.8. Mixtures of diols and 
mixtures of anhydrides often are used; accordingly, the molecular weight 
of the individual polyester chains will generally vary somewhat, as will 
the kinds and numbers of mers in the chains. While some monomers having 
functionality greater than 2 may be used, it is highly desired that the 
functionality of the polyester chain not exceed 3, lest cross-link density 
be too high, resulting in brittleness. 
If the hydroxyl value of the polyester were less than about 150, the 
viscosity would be unacceptably high. A coating made from a polyester 
having a hydroxyl value greater than 275 would be too brittle. If the acid 
number of the polyester were less than 2, the wetting of pigments in a 
coating composition would be diminished. On the other hand, an acid number 
greater than 7 would be harmful to the coating's resistance to methyl 
ethyl ketone (MEK), its hardness, and its water-absorption. Preferably, 
the hydroxyl value is from about 180 to about 260 and the acid number is 
preferably from about 2 to about 5. 
The polyols are predominately diols so that the polyesters formed are 
substantially linear. However, a small amount of triols, e.g., trimethylol 
propane (TMP) may be used so as to provide branches on some of the 
polyester chains. Triols are used in an amount sufficient to provide 
cross-linking to prevent spray gun-stringing of a paint made from the 
coating composition. Preferably triols comprise no more than about 15 mole 
percent, more preferably no more than about 5 mole percent, of the total 
polyol content. 
Among the preferred polyols which can be used are: aliphatic polyols, 
particularly aliphatic diols or triols, most preferably those containing 
from 2 to 10 carbon atoms. Examples include ethylene glycol; 
1,2-propanediol; 1,3-propanediol; 1,4-butanediol; 1,5-pentanediol; 
glycerol; 1,6-hexanediol; neopentyl glycol; diethylene glycol; 
2-methyl-1,3-propanediol; dipropylene glycol; triethyleneglycol; 
2,2,4-trimethylpentane-1,3-diol; 
2,2-dimethyl-3-hydroxypropyl-2,2-dimethyl-3-hydroxypropionate; 
1,4-cyclohexanedimethanol; 1,2,3-butanetriol, trimethylol-ethane, and 
trimethylol propane. Preferred are those aliphatic diols or triols 
selected from the class consisting of 2,2,4-trimethylpentane-1,3-diol; 
2,2-dimethyl-3-hydroxypropy-2,2-dimethyl-3-hydroxypropionate; 
2-methyl-1,3-propanediol; diethylene glycol; dipropylene glycol; 
1,6-hexanediol; and trimethylol propane. Preferred polyesters of this 
invention are prepared from mixtures of polyols wherein hexanediol 
constitutes at least about 28% and preferably from about 40 to about 70% 
by weight of the polyol mixture. A polyol mixture containing from about 40 
to about 60% hexanediol is particularly preferred. Also preferred are 
polyol mixtures containing the 2-methyl-1,3-propanediol because of its 
ability to enhance the hardness of a coating composition without hurting 
its flexibility. 
Higher functionality polyols such as tetrols can be used at very low levels 
but they are not preferred. An example of a tetrol would be 
1,2,3,4-butanetetrol. 
Between about 10 and about 50 wt % of the monomers used to form the 
polyester composition are anhydrides having the formula: 
##STR2## 
where R.sup.1 is a non-aromatic, saturated or unsaturated hydrocarbon 
radical having from 6 to 30 carbon atoms, R.sup.2 is hydrogen or a 
non-aromatic saturated or unsaturated hydrocarbon radical having from 1 to 
8 carbon atoms, and R.sup.1 and R.sup.2 have, in total, from 8 to 30 
carbon atoms. Anhydrides of formula (I) comprise from about 10 to about 50 
wt %, preferably from about 20 to about 40 wt %, of the monomers used to 
form the polyester composition. A preferred monomer of Formula I is 
dodecenylsuccinic anhydride (DDSA) (alternately named 
dihydro-3-(tetrapropenyl)-2,5-furandione), generally available as a 
mixture of isomers. The use of anhydrides of formula (I), such as DDSA and 
octadecenylsuccinic anhydride, in the formation of the low molecular 
weight polyesters of this invention provide low viscosity to liquid 
polyester compositions and enhanced flexibility of cured coatings. They 
may be the only anhydride(s) used, but typically they are used in 
conjunction with other non-aromatic or aromatic anhydrides, such as 
succinic anhydride, methylsuccinic anhydride, phthalic anhydride, 
tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, 
hexahydrophthalic anhydride, methylhexahydro-phthalic anhydride, 
tetrachlorophthalic anhydride, endomethylene tetrahydrophthalic anhydride, 
chlorendic anhydride, itaconic anhydride, citraconic anhydride, maleic 
anhydride, and trimellitic anhydride. 
To form a curable composition, such as a coating composition, the polyester 
compositions, as described above, are combined with a cross-linking agent. 
The cross-linking agent is one which is capable of reacting with the 
active hydrogens (primarily --OH hydrogens) in the polyester to give a 
thermoset composition upon curing. Examples of suitable cross-linking 
agents are aminoplasts and polyisocyanates including blocked 
polyisocyanates. 
Aminoplasts are obtained by the condensation reaction of formaldehyde with 
an amine or an amide. The most common amines or amides are melamine, urea 
or benzoguanamine. However, condensation with other amines or amides can 
be employed. While the aldehyde employed is most often formaldehyde, other 
aldehydes such as acetaldehyde, crotonaldehyde, benzaldehyde and furfural 
may be used. The aminoplast contains methylol or similar alkylol groups, 
and preferably, at least a portion of these alkylol groups are etherified 
by reaction with alcohol to provide organic solvent-soluble resins. Any 
monohydric alcohol can be employed for this purpose including such 
alcohols as methanol, ethanol, butanol and hexanol. Preferably, the 
aminoplasts which are used are melamine-, urea- or 
benzoguanamine-formaldehyde condensates etherfied with an alcohol 
containing 1 to 4 carbon atoms such as methanol, ethanol, butanol or 
mixtures thereof. 
The amount of aminoplast which is used from about 10 to 70 percent by 
weight, preferably 15 to 50 percent by weight, based on total weight of 
the aminoplast and polyester. Amounts less than 10 percent by weight 
usually result in insufficient cure, whereas amounts greater than 70 
percent by weight serve no particular benefit. 
Polyisocyanates and blocked polyisocyanates may also be used as curing 
agents. Examples of suitable polyisocyanates include monomeric 
polyisocyanates such as toluene diisocyanate and 
4,4'-methylene-bis(cyclohexyl isocyanate), isophorone diisocyanate and 
NCO-prepolymers such as the reaction products of monomeric polyisocyanate 
such as those mentioned above with polyester or polyether polyols. A 
particularly useful isocyanate is the biuret from 1,6-hexamethylene 
diisocyanate commercially available from Bayer.RTM. AG as Desmodur.RTM. N. 
Optionally, the polyisocyanate may be blocked. Examples of suitable 
blocking agents are those materials which would unblock at elevated 
temperatures such as caprolactam. Blocked isocyanates can be used to form 
stable one-package systems. Polyfunctional isocyanates with free 
isocyanate groups can be used to form two-package room temperature curable 
systems. In these systems, the polyester and isocyanate curing agent are 
mixed just prior to their application. The amount of isocyanate or blocked 
poyisocyanate curing agent which is used can vary between about 0.2 to 
1.5, preferably from 0.3 to 1.3 equivalents of NCO per equivalent of 
active hydrogen of the polyester. On a weight basis, the ratio of 
isocyanate or blocked isocyanate curative relative to polyester is 
generally within the ranges of weight ratios of aminoplast curative to 
polyester set forth above. 
Because polyester compositions incorporating significant amounts of 
anhydride monomer of formula (I) have low viscosities, very high solids 
solutions of the polyesters in organic solvent can be formed and utilized 
in coating compositions. This affords coating compositions having low 
VOCs. 
The high solids coating compositions preferably contain greater than 50 
percent non-volatile solids by volume and contain most preferably greater 
than 60 percent non-volatile solids by volume. 
Besides the polyester oligomer and the crosslinking agent, the high solids 
coating composition can optionally contain other hydroxyl functional 
polymers, pigment, liquid diluent, plasticizer, anti-oxidants. UV light 
absorbers, surfactants, flow control agents, as is well known in the art. 
Examples of flow control agents are crosslinked polymeric microparticles 
such as described in U.S. Pat. No. 4,147,688. 
Coating compositions employing the polyesters of the present invention are 
especially suitable for application by coil coating and by spraying, 
although other conventional methods of coating including brushing, dipping 
and flow coating can be employed, if desired. Usual spray techniques and 
equipment are utilized. High solids coatings using the polyesters of the 
present invention can be applied virtually over any substrate including 
wood, metal, glass, cloth, plastic, foams and the like, as well as over 
various primers. Coating compositions employing the polyesters of the 
present invention are useful for a wide variety of applications. They can 
be used for coating automotive parts such as automobile bodies and truck 
cabs. Also, they can be used for other coating applications such as 
coatings for appliance parts such as refrigerators and washing machines. 
The coating compositions made possible by the polyesters of this invention 
are particularly useful for coating the reflectors of lighting fixtures, 
lightweight mini-blinds, shelves, and the like. The coating may be thicker 
than the metal substrate and it may be achieved in one pass through a coil 
coater instead of the two passes required heretofore. 
In general, coating thicknesses will vary depending upon the application 
desired. In general, coatings from about 0.1 to 5 mils have been found to 
be useful in most applications, and coatings from about 0.8 to 1.2 mils 
have been found to be more useful. 
After application to the substrate, the coatings are cured. Curing is 
usually conducted at temperatures of about 100.degree. to 260.degree. C., 
and in most cases, the cure schedule is from about 15 seconds to about 30 
minutes. Higher or lower temperatures with correspondingly shorter or 
longer times can be utilized, although the exact cure schedule best 
employed depends upon the nature of the substrate, as well as the 
particular components used in formulating the coating compositions. If a 
coating is applied on a coil line, the composition is typically cured in a 
coil oven with a temperature and dwell time determined according to the 
particular coating composition. With aminoplast curing agents, acid 
catalysts can be employed, if desired, as they usually permit the use of 
lower temperature and shorter times for cure. 
The polyester compositions of the present invention may be used as the sole 
polyester component of a coating composition, and coatings formed from 
such a composition exhibit surprisingly good flexibility. 
Polyester compositions of the present invention are also found to be used 
advantageously as additives to polyester coating compositions, such as 
those used in coil coating operations. In polyester coating compositions 
of the prior art, the polyesters typically have number average molecular 
weights of from about 2000 to about 5000 and OH numbers from about 15 to 
about 50. Certain advantages are achieved by using such polyesters as the 
major polyester, i.e., from about 70 to about 90 wt % of the total 
polyester content, in conjunction with a polyester composition in 
accordance with the invention as a minor polyester, i.e., from about 10 to 
about 30 wt %, preferably at least about 20% and more preferably at least 
about 30%. For example, coating solids levels can be raised, pigment 
wetting is improved, and surface defects of the applied and cured coating 
are eliminated. 
The invention will be further described by reference to the following 
examples. Unless otherwise indicated, all parts are by weight percentages 
based on 100% solids. 
EXAMPLE 1 
Polyester 1 is formulated as follows (99.87% of solids are monomer 
components of polyester): 
______________________________________ 
1. MPDiol (Arco).sup.1 
monomer 34.36 
2. Trimethylopropane 
monomer 0.47 
3. 1,6-hexanediol monomer 11.21 
4. DDSA.sup.2 monomer 28.90 
5. Phthalic Anhydride 
monomer 30.13 
6. HHPA.sup.3 monomer 0.47 
7. Triphenyl phosphite 
oxidation inhibitor 
0.02 
8. Fascat 4100 catalyst 0.11 
9. Butyl Acetate solvent 11.73 
Solids Charge 
105.67 
Theoretical Losses 
5.67 
Solids Yield 100.00 
Solution Yield 
111.73 
______________________________________ 
.sup.1 2methyl-1,3-propanediol 
.sup.2 Dodecenylsuccinic Anhydride 
.sup.3 Hexadydrophthalic Anhydride 
Components 1-8 were charged while purging with inert gas. The reactor is 
slowly heated to 80.degree.-90.degree. C. to melt components; onset of 
exotherm was observed--cooling was applied as needed to maintain 
temperature below 110.degree.-115.degree. C., reaction mixture held at 
temperature for 1 hour. The reaction mixture is heated to 
220.degree.-230.degree. C., and viscosity and acid value monitored until a 
maximum value of 3.5 was obtained. The reactor is cooled to 120.degree. 
C., and then butyl acetate is added. The properties of the polyester 
composition are as follows: 
______________________________________ 
Viscosity (at 85% Solids): 
Z1 
Non-Volatile Materials: 85.0 
Solvent: Butyl Acetate 
Color: 2-3 
AV/NV (Acid Value based on Solids): 
2.0 
Weight Per Gallon (WPG): 8.89 
OHN/NV (Hydroxyl Number Based on Solids): 
190.3 
Appearance: Clear 
NV (Non-Volatile Volume): 
81.8 
GPC Analysis: 
Mn: 770 
Mw: 1240 
Mz: 1890 
Dispersity (Mw/Mn): 
1.61 
______________________________________ 
EXAMPLE 2 
Polyester 2 is formulated as follows (99.88% of solids are monomer 
components of polyester): 
______________________________________ 
1. MPDiol (Arco) monomer 29.64 
2. Trimethylopropane 
monomer 0.47 
3. 1,6-hexanediol monomer 16.65 
4. DDSA monomer 28.51 
5. Phthalic Anhydride 
monomer 29.73 
6. HHPA monomer 0.47 
7. Triphenyl phosphite 
oxidation inhibitor 
0.02 
8. Fascat 4100 catalyst 0.10 
9. Butyl Acetate solvent 11.73 
Solids Charge 
105.60 
Theoretical Losses 
5.60 
Solids Yield 100.00 
Solution Yield 
111.73 
______________________________________ 
Components 1-8 were charged while purging with inert gas. The reactor is 
slowly heated to 80.degree.-90.degree. C. to melt components; onset of 
exotherm was observed--cooling was applied as needed to maintain 
temperature below 110.degree.-115.degree. C., reaction mixture held at 
temperature for 1 hour. The reaction mixture is heated to 
220.degree.-230.degree. C., and viscosity and acid value monitored until a 
maximum value of 3.5 was obtained. The reactor is cooled to 120.degree. 
C., and then butyl acetate is added. The properties of the polyester 
composition are as follows: 
______________________________________ 
Viscosity (at 85% Solids): 
Z+ 
Non-Volatile Materials: 84.7 
Solvent: Butyl Acetate 
Color: 1 
AV/NV (Acid Value based on Solids): 
2.7 
Weight Per Gallon (WPG): 8.87 
OHN/NV (Hydroxyl Number Based on Solids): 
187.81 
Appearance: Clear 
NV (Non-Volatile Volume): 
81.5 
GPC Analysis: 
Mn: 740 
Mw: 1210 
Mz: 1880 
Dispersity (Mw/Mn): 
1.63 
______________________________________ 
EXAMPLE 3 
Polyester 3 is formulated as follows (99.88% of solids are monomer 
components of polyester): 
______________________________________ 
1. MPDiol (Arco) monomer 24.94 
2. Trimethylopropane 
monomer 0.46 
3. 1,6-hexanediol monomer 22.07 
4. DDSA monomer 28.13 
5. Phthalic Anhydride 
monomer 29.34 
6. HHPA monomer 0.46 
7. Triphenyl phosphite 
oxidation inhibitor 
0.02 
8. Fascat 4100 catalyst 0.10 
9. Butyl Acetate solvent 11.73 
Solids Charge 
105.52 
Theoretical Losses 
5.52 
Solids Yield 100.00 
Solution Yield 
111.73 
______________________________________ 
Components 1-8 were charged while purging with inert gas. The reactor is 
slowly heated to 80.degree.-90.degree. C. to melt components; onset of 
exotherm was observed--cooling was applied as needed to maintain 
temperature below 110.degree.-115.degree. C., reaction mixture held at 
temperature for 1 hour. The reaction mixture is heated to 
220.degree.-230.degree. C., and viscosity and acid value monitored until a 
maximum value of 5.0 was obtained. The reactor is cooled to 120.degree. 
C., and then butyl acetate is added. The properties of the polyester 
composition are as follows: 
______________________________________ 
Viscosity (at 85% Solids): 
Z- 
Non-Volatile Materials: 85.3 
Solvent: Butyl Acetate 
Color: 2+ 
AV/NV (Acid Value based on Solids): 
3.1 
Weight Per Gallon (WPG): 8.90 
OHN/NV (Hydroxyl Number Based on Solids): 
185.4 
Appearance: Clear 
NV (Non-Volatile Volume): 
82.18 
GPC Analysis: 
Mn: 800 
Mw: 1360 
Mz: 2110 
Dispersity (Mw/Mn): 
1.70 
______________________________________ 
EXAMPLE 4 
Polyester 4 is formulated as follows (99.84% of solids are monomer 
components of polyester): 
______________________________________ 
1. MPDiol (Arco) monomer 28.82 
2. Trimethylopropane 
monomer 5.18 
3. 1,6-hexanediol monomer 12.84 
4. DDSA monomer 31.54 
5. Phthalic Anhydride 
monomer 26.40 
6. HHPA monomer 0.45 
7. Triphenyl phosphite 
oxidation inhibitor 
0.02 
8. Fascat 4100 catalyst 0.14 
9. Butyl Acetate solvent 11.73 
Solids Charge 
105.39 
Theoretical Losses 
5.39 
Solids Yield 100.00 
Solution Yield 
111.73 
______________________________________ 
Components 1-8 were charged while purging with inert gas. The reactor is 
slowly heated to 80.degree.-90.degree. C. to melt components; onset of 
exotherm was observed--cooling was applied as needed to maintain 
temperature below 110.degree.-115.degree. C., reaction mixture held at 
temperature for 1 hour. The reaction mixture is heated to 
220.degree.-230.degree. C., and viscosity and acid value monitored until a 
maximum value of 5.0 was obtained. The reactor is cooled to 120.degree. 
C., and then butyl acetate is added. The properties of the polyester 
composition are as follows: 
______________________________________ 
Viscosity (at 85% Solids): 
Z1 
Non-Volatile Materials: 84.2 
Solvent: Butyl Acetate 
Color: 1+ 
AV/NV (Acid Value based on Solids): 
2.2 
Weight Per Gallon (WPG): 8.92 
OHN/NV (Hydroxyl Number Based on Solids): 
219.9 
Appearance: Clear 
NV (Non-Volatile Volume): 
80.2 
GPC Analysis: 
Mn: 780 
Mw: 1250 
Mz: 1900 
Dispersity (Mw/Mn): 
1.60 
______________________________________ 
EXAMPLE 5 
Polyester 5 is formulated as follows (99.89% of solids are monomer 
components of polyester): 
______________________________________ 
1. MPDiol (Arco) monomer 1.39 
2. Trimethylopropane 
monomer 5.32 
3. 1,6-hexanediol 
monomer 10.06 
4. DDSA monomer 28.50 
5. Phthalic Anhydride 
monomer 29.29 
6. HHPA monomer 0.46 
7. Triphenyl phosphite 
oxidation inhibitor 
0.01 
8. Fascat 4100 catalyst 0.10 
9. MPDiol monomer 30.41 
10. Butyl Acetate solvent 11.49 
Solids Charge 105.54 
Theoretical Losses 5.54 
Solids Yield 100.00 
Solution Yield 111.49 
______________________________________ 
Components 1-8 were charged while purging with inert gas. The reactor is 
slowly heated to 80.degree.-90.degree. C. to melt components; onset of 
exotherm was observed--cooling was applied as needed to maintain 
temperature below 110.degree.-115.degree. C., reaction mixture held at 
temperature for 1 hour. The reaction mixture is heated to 
130.degree.-135.degree. C. and Acid Value monitored, when an acid value of 
240.0 is obtained then item 9 is added to the reaction mixture. The 
reaction mixture is heated to 220.degree.-230.degree. C., and viscosity 
and acid value monitored until a maximum value of 5.0 was obtained. The 
reactor is cooled to 120.degree. C., and then butyl acetate is added. The 
properties of the polyester composition are as follows: 
______________________________________ 
Viscosity (at 85% Solids): 
Z2- 
Non-Volatile Materials: 84.45 
Solvent: Butyl Acetate 
Color: 1+ 
AV/NV (Acid Value based on Solids): 
2.80 
Weight Per Gallon (WPG): 8.90 
OHN/NV (Hydroxyl Number Based on Solids): 
219.70 
Appearance: Clear 
NV (Non-Volatile Volume): 
81.15 
GPC Analysis: 
Mn: 730 
Mw: 1160 
Mz: 1760 
Dispersity (Mw/Mn): 
1.59 
______________________________________ 
EXAMPLE 6 
Polyester 6 is formulated as follows (99.90% of solids are monomer 
components of polyester): 
______________________________________ 
1. MPDiol (Arco) monomer 1.27 
2. Trimethylopropane 
monomer 4.84 
3. 1,6-hexanediol 
monomer 9.15 
4. DDSA monomer 33.02 
5. Phthalic Anhydride 
monomer 22.69 
6. HHPA monomer 0.42 
7. Triphenyl phosphite 
oxidation inhibitor 
0.01 
8. Fascat 4100 catalyst 0.09 
9. MPDiol monomer 33.54 
10. Butyl Acetate solvent 7.53 
Solids Charge 105.04 
Theoretical Losses 5.04 
Solids Yield 100.00 
Solution Yield 107.53 
______________________________________ 
Components 1-8 were charged while purging with inert gas. The reactor is 
slowly heated to 80.degree.-90.degree. C. to melt components; onset of 
exotherm was observed--cooling was applied as needed to maintain 
temperature below 110.degree.-115.degree. C., reaction mixture held at 
temperature for 1 hour. The reaction mixture is heated to 
130.degree.-135.degree. C. and Acid Value monitored, when an acid value of 
244.0 is obtained then item 9 is added to the reaction mixture. The 
reaction mixture is heated to 220.degree.-230.degree. C., and viscosity 
and acid value monitored until a maximum value of 5.0 was obtained. The 
reactor is cooled to 120.degree. C., and then butyl acetate is added. The 
properties of the polyester composition are as follows: 
______________________________________ 
Viscosity (at 85% Solids): 
Z2 
Non-Volatile Materials: 84.4 
Solvent: Butyl Acetate 
Color: 1-2 
AV/NV (Acid Value based on Solids): 
3.3 
Weight Per Gallon (WPG): 8.90 
OHN/NV (Hydroxyl Number Based on Solids): 
256.8 
Appearance: Clear 
NV (Non-Volatile Volume): 
81.1 
GPC Analysis: 
Mn: 650 
Mw: 980 
Mz: 1470 
Dispersity (Mw/Mn): 
1.51 
______________________________________ 
EXAMPLE 7 
Polyester 7 is formulated as follows (99.88% of solids are monomer 
components of polyester): 
______________________________________ 
1. MPDiol (Arco) monomer 24.65 
2. Trimethylopropane 
monomer 0.46 
3. 1,6-hexanediol 
monomer 21.82 
4. DDSA monomer 27.81 
5. Phthalic Anhydride 
monomer 0.44 
6. HHPA monomer 30.17 
7. Triphenyl phosphite 
oxidation inhibitor 
0.02 
8. Fascat 4100 catalyst 0.10 
9. Butyl Acetate solvent 11.72 
Solids charge 105.46 
Theoretical Losses 5.46 
Solids Yield 100.00 
Solution Yield 111.72 
______________________________________ 
Components 1-8 were charged while purging with inert gas. The reactor is 
slowly heated to 80.degree.-90.degree. C. to melt components; onset of 
exotherm was observed--cooling was applied as needed to maintain 
temperature below 110.degree.-115.degree. C., reaction mixture held at 
temperature for 1 hour. The reaction mixture is heated to 
220.degree.-230.degree. C., and viscosity and acid value monitored until a 
maximum value of 5.0 was obtained. The reactor is cooled to 120.degree. 
C., and then butyl acetate is added. The properties of the polyester 
composition are as follows: 
______________________________________ 
Viscosity (at 85% Solids): 
X- 
Non-Volatile Materials: 85.1 
Solvent: Butyl Acetate 
Color: 2- 
AV/NV (Acid Value based on Solids): 
4.6 
Weight Per Gallon (WPG): 8.89 
OHN/NV (Hydroxyl Number Based on Solids): 
183.2 
Appearance: Clear 
NV (Non-Volatile Volume): 
81.8 
GPC Analysis: 
Mn: 790 
Mw: 1300 
Mz: 2010 
Dispersity (Mw/Mn): 
1.64 
______________________________________ 
EXAMPLE 8 
Polyester 8 is formulated as follows (99.89% of solids are monomer 
components of polyester): 
______________________________________ 
1. MPDiol (Arco) monomer 22.92 
2. Trimethylopropane 
monomer 0.42 
3 1,6-hexanediol 
monomer 20.28 
4. ODSA.sup.1 monomer 33.96 
5. Phthalic Anhydride 
monomer 26.96 
6. HHPA monomer 0.42 
7. Triphenyl phosphite 
oxidation inhibitor 
0.02 
8. Fascat 4100 catalyst 0.09 
9. Butyl Acetate solvent 14.30 
Solids charge 105.07 
Theoretical Losses 5.07 
Solids Yield 100.00 
Solution Yield 114.30 
______________________________________ 
.sup.1 Octadecenylsuccinic Anhydride 
Components 1-8 were charged while purging with inert gas. The reactor is 
slowly heated to 80.degree.-90.degree. C. to melt components; onset of 
exotherm was observed--cooling was applied as needed to maintain 
temperature below 110.degree.-115.degree. C., reaction mixture held at 
temperature for 1 hour. The reaction mixture is heated to 
220.degree.-230.degree. C., and viscosity and acid value monitored until a 
maximum value of 5.0 was obtained. The reactor is cooled to 120.degree. 
C., and then butyl acetate is added. The properties of the polyester 
composition are as follows: 
______________________________________ 
Viscosity (at 85% Solids): 
V- 
Non-Volatile Materials: 83.8 
Solvent: Butyl Acetate 
Color: 2- 
AV/NV (Acid Value based on Solids): 
3.6 
Weight Per Gallon (WPG): 8.66 
OHN/NV (Hydroxyl Number Based on Solids): 
171.14 
Appearance: Clear 
NV (Non-Volatile Volume): 
80.9 
GPC Analysis: 
Mn: 890 
Mw: 1730 
Mz: 3210 
Dispersity (Mw/Mn): 
1.94 
______________________________________ 
EXAMPLE 9 
Polyester 9 is formulated as follows (99.88% of solids are monomer 
components of polyester): 
______________________________________ 
1. MPDiol (Arco) monomer 24.47 
2. Trimethylopropane 
monomer 0.45 
3. 1,6-hexanediol 
monomer 21.66 
4. ODSA monomer 25.17 
5. Phthalic Anhydride 
monomer 33.05 
6. HHPA monomer 0.45 
7. Triphenyl phosphite 
oxidation inhibitor 
0.02 
8. Fascat 4100 catalyst 0.10 
9. Butyl Acetate solvent 11.73 
Solids charge 105.37 
Theoretical Losses 5.37 
Solids Yield 100.00 
Solution Yield 111.73 
______________________________________ 
Components 1-8 were charged while purging with inert gas. The reactor is 
slowly heated to 80.degree.-90.degree. C. to melt components; onset of 
exotherm was observed--cooling was applied as needed to maintain 
temperature below 110.degree.-115.degree. C., reaction mixture held at 
temperature for 1 hour. The reaction mixture is heated to 
220.degree.-230.degree. C., and viscosity and acid value monitored until a 
maximum value of 5.0 was obtained. The reactor is cooled to 120.degree. 
C., and then butyl acetate is added. The properties of the polyester 
composition are as follows: 
______________________________________ 
Viscosity (at 85% Solids): 
W+ 
Non-Volatile Materials: 85.5 
Solvent: Butyl Acetate 
Color: 2 
AV/NV (Acid Value based on Solids): 
3.8 
Weight Per Gallon (WPG): 8.88 
OHN/NV (Hydroxyl Number Based on Solids): 
185.93 
Appearance: Clear 
NV (Non-Volatile Volume): 
82.4 
GPC Analysis: 
Mn: 820 
Mw: 1490 
Mz: 2600 
Dispersity (Mw/Mn): 
1.81 
______________________________________ 
EXAMPLES 10-12 & COMATIVE EXAMPLE 1 
A series of white coating compositions having the formulations shown in 
Table I were prepared by dispersing components 1-5 on a sand mill to a 
Hegman grind of 7.5 and then letting down this mill base by adding 
components 6-27 and mixing under low shear until homogeneous. 
TABLE I 
______________________________________ 
Component Example No. 
No. Description C.E. 1 10 11 12 
______________________________________ 
1 R-4350 (Polyester Resin)* 
28.35 18.48 
23.39 
36.17 
2 Aromatic 150 solvent 
1.83 -- -- -- 
3 Butyl Carbitol Acetate 
-- 2.12 2.65 -- 
4 Aromatic 100 solvent 
-- -- -- -- 
5 Titanium Dioxide 33.81 49.97 
36.89 
37.78 
6 R-4350 (Polyester Resin) 
15.34 9.98 14.67 
-- 
7 R-2643 (Polyester Resin)** 
-- -- -- -- 
8 Polyester 1 -- 7.89 -- -- 
9 Polyester 2 -- -- 9.64 -- 
10 Polyester 3 -- -- -- 9.88 
11 Acrylic Resin -- 1.38 0.58 1.05 
12 RESIMENE 747 (Curative) 
5.15 -- -- -- 
13 RESIMENE 751 (Curative) 
-- 5.83 7.38 7.70 
14 Acrylic Flow Aid 0.69 0.04 0.07 0.35 
15 NACURE 1051 (Catalyst) 
0.37 -- -- -- 
16 NACURE 1557 (Catalyst) 
-- 1.29 0.82 0.84 
17 SILWET L-7500 Flow Control 
-- 0.06 0.16 0.21 
18 VERSAFLOW CUT Polyethylene 
-- -- -- 0.21 
19 2-ethyl hexanol 1.58 -- -- -- 
20 1-butanol 1.58 -- 2.08 2.94 
21 DPGME*** 1.58 -- -- -- 
22 Butyl Cellosolve 1.34 -- -- -- 
23 Aromatic 150 8.38 -- -- -- 
24 Aromatic 100 -- -- -- 2.03 
25 Acetone -- 1.64 -- -- 
26 Butyl Carbitol Acetate 
-- 1.32 1.67 -- 
27 Epon 828 (Epoxy Resin) 
-- -- -- 0.83 
______________________________________ 
*M.sub.n 3520; OH #(NV) 30 .+-. 3; 65% solids 
**M.sub.n 4330; OH #(NV) 18 .+-. 6; 60% solids 
***DPGME is dipropylene glycol methyl ether 
The compositions in Table I were applied in a coil coating process to 
aluminum sheet metal to a wet thickness of about 1.15 mils, dried, and 
then cured under the conditions shown in Table II wherein the coating 
composition properties and film properties are also shown. 
TABLE II 
______________________________________ 
Example 
Properties C.E. 1 10 11 12 
______________________________________ 
Coating Composition 
Properties 
% Volume Solids 
50.1 62.2 62.5 66.5 
Viscosity 500 cps 800 cps 1200 cps 
432 cps 
WPG (lbs./gallon) 
11.5 11.8 11.9 12.0 
VOC 3.36 2.40 2.38 2.43 
Cure Conditions 
PMT 450.degree. F. 
450.degree. F. 
450.degree. F. 
450.degree. F. 
Dwell Time 28 sec. 28 sec. 28 sec. 
22 sec. 
Film Properties 
Film Thickness (mils) 
0.75-0.80 
0.75-0.80 
0.75-0.80 
0.75-0.80 
60.degree. Gloss 
95.3% 95.2% 95.0 95.0 
Pencil Hardness 
H H H H 
MEK Rubs 100 100 100 100 
T-Bend Pass 0T Pass 0T Pass 0T 
Pass 0T 
______________________________________ 
EXAMPLES 13 and 14 and COMATIVE EXAMPLE 2 
A series of white coating compositions having the formulations shown in 
Table III were prepared by dispersing components 1-8 on a sand mill to a 
Hegman grind of 7.5 and then letting down this mill base by adding 
components 9-26 and mixing under low shear until homogeneous. 
TABLE III 
______________________________________ 
Component Example No. 
No. Description C.E. 2 13 14 
______________________________________ 
1 R-2643 (Polyester Resin) 
14.01 15.43 
16.00 
2 MIAK* -- 5.14 5.19 
3 Aromatic 150 4.67 -- -- 
4 Titanium Dioxide 
28.01 30.86 
30.90 
5 R-2643 (Polyester Resin) 
0.21 -- -- 
6 MIAK 0.07 0.05 -- 
7 Raven 1040 0.03 0.03 -- 
8 Polyester 1 -- 0.23 -- 
9 R-2643 (Polyester Resin) 
33.74 27.22 
26.65 
10 Polyester 1 -- 5.45 -- 
11 Polyester 2 -- -- 5.67 
12 Acrylic Resin 1.06 1.10 1.10 
13 RESIMENE 747 (Curative) 
2.71 -- -- 
14 RESIMENE 751 (Curative) 
-- 7.09 7.09 
15 CYMEL 325 (Curative) 
1.91 -- -- 
16 Acrylic Flow Aid 
1.06 0.06 0.06 
17 NACURE 1051 (Catalyst) 
0.42 -- -- 
18 NACURE 1557 (Catalyst) 
-- 0.82 0.82 
19 SILWET L-7500 0.21 0.21 0.21 
20 VERSAFLOW CUT 0.21 -- -- 
21 2-ethyl hexanol 1.59 -- -- 
22 1-butanol 3.18 1.85 1.85 
23 Aromatic 150 5.31 -- -- 
24 Acetone -- 1.85 1.85 
25 Butyl Carbitol Acetate 
1.59 1.85 1.85 
26 Epon 828 (Epoxy Resin) 
-- 0.75 0.75 
______________________________________ 
*MIAK means methyl isoamyl ketone 
The compositions in Table III were applied in a coil coating process to 
aluminum sheet metal to a wet thickness of about 1.35 mils, dried, and 
then cured under the conditions shown in Table IV wherein the coating 
compositon properties and film properties are also shown. 
TABLE IV 
______________________________________ 
Example 
Properties C.E.2 13 14 
______________________________________ 
Coating Formulation Properties 
% Volume Solids 46.8 55.1 55.1 
Viscosity 620 cps 560 cps 580 cps 
WPG (lbs./gallon) 10.5 10.8 10.80 
VOC 3.90 3.03 3.03 
PMT 450.degree. F. 
450.degree. F. 
450.degree. F. 
Dwell Time 28 sec. 28 sec. 28 sec. 
Film Properties 
Film Thickness (mil) 
0.75-0.80 
0.75-0.80 
0.75-0.80 
60.degree. Gloss 96.2% 91.0% 95.3% 
Pencil Hardness H H H 
MEK Rubs 100 100 100 
T-Bend Pass OT Pass OT Pass OT 
______________________________________ 
EXAMPLES 15 and 16 
Two white coatings were prepared with the high solids resins of this 
invention. Examples 15 and 16 compare the polyester resins of example 2 
and 3, respectively. Components 1-4 were dispersed on a sand mill to a 
Hegman 7.5, then this mill base was let down by adding components 5-11 and 
mixing under low shear. 
TABLE V 
______________________________________ 
Component Example No. 
No. Description 15 16 
______________________________________ 
1 Polyester 2 41.15 -- 
2 Polyester 3 -- 41.15 
3 Titanium Dioxide 40.77 40.77 
4 CYMEL 303 (Curative) 
9.06 9.06 
5 Acrylic Resin 1.30 1.30 
6 NACURE 1557 (Catalyst) 
0.60 0.60 
7 SILWET L-7500 0.18 0.18 
8 Acrylic Resin - Flow Aid 
0.15 0.15 
9 Butyl Carbitol Acetate 
2.26 2.26 
10 MIAK 2.26 2.26 
11 1-butanol 2.26 2.26 
______________________________________ 
The compositions in Table V were applied in a coil coating process to 
aluminum sheet metal to a wet thickness of about 1 mil, dried, and then 
cured under the conditions shown in Table VI wherein the coating 
compositon properties and film properties are also shown. 
TABLE VI 
______________________________________ 
Example 
Properties 17 18 
______________________________________ 
Coating Composition Properties 
% Volume Solids 77.00 77.00 
Viscosity 860 cps 720 cps 
WPG (lbs./gallon) 12.3 12.3 
VOC 1.79 1.79 
Curing Conditions 
PMT 450.degree. F. 
450.degree. F. 
Dwell Time 28 sec. 28 sec. 
Film Properties 
Film Thickness (mil) 
0.75-0.80 0.75-0.80 
60.degree. Gloss 92.8% 94.9 
Pencil Hardness H H 
MEK Rubs 100 100 
T-Bend Fail 3T Fail 3T 
______________________________________ 
EXAMPLE 19 AND COMATIVE EXAMPLE 3 
Two white coatings were prepared with and without the high solids resin of 
this invention as shown in Table VII. Components 1-6 were dispersed on a 
sand mill to a Hegman 7.5, then this mill base was let down by adding 
components 7-29 and mixing under low shear. 
TABLE VII 
______________________________________ 
Components Example No. 
No. Description C.E.3 19 
______________________________________ 
1 R-4350 Polyester Resin 
19.79 -- 
2 R-5017* Polyester Resin 
-- 12.97 
3 Polyester 3 -- 1.35 
4 Aromatic 150 4.52 3.15 
5 1-butanol -- 0.41 
6 Titanium Dioxide 32.23 35.82 
7 R-4350 11.61 13.63 
8 R-2043" Polyester Resin 
2.52 -- 
9 Acrylic Resin 0.75 -- 
10 Polyester 3 -- 6.99 
11 Resimene 747 2.74 -- 
12 Resimene 741 2.35 6.81 
13 Zeospheres -- 5.24 
14 Acrylic Resin -- 0.23 
15 R-4350 2.58 -- 
16 Aromatic 150 2.97 -- 
17 Cab-O-Sil 0.21 -- 
18 Talc 1.24 -- 
19 Nacure 1051 -- 0.35 
20 PTSA 0.25 -- 
21 Iso-propanol 0.25 -- 
22 Flattening Agent -- 2.27 
23 Anti-popping Agent 
-- 0.30 
24 Aromatic 150 4.58 10.48 
25 2-ethyl hexanol 2.00 -- 
26 Butyl Carbitol Acetate 
3.00 -- 
27 Talc 5.36 -- 
28 Aromatic 150 1.00 -- 
______________________________________ 
*M.sub.n 3570; OH# (NV)32 .+-. 5; 65% solids 
**M.sub.n 2770; OH# (NV)85 .+-. 5 
The compositions in Table VII were applied in a coil coating process to 
aluminum sheet metal to a wet thickness of about 1.73 mils for C.E.3 and 
about 2.27 mils for Example 19, dried, and then cured under the conditions 
shown in Table VIII wherein the coating composition properties and film 
properties are also shown. 
TABLE VIII 
______________________________________ 
Example 
Properties C.E.3 19 
______________________________________ 
Coating Formulation Properties 
% Volume Solids 49.4% 55.6% 
Viscosity 560 cps 540 cps 
WPG (lbs./gallon) 11.7 12.3 
VOC 3.75 3.09 
PMT 435.degree. F. 
435.degree. F. 
Dwell Time 22 sec. 22 sec. 
Film Properties 
Film Thickness 0.85 mil 
1.25 mil 
60.degree. Gloss 40 47.1 
Pencil Hardness H H 
MEK Rubs 100 100 
T-Bend Pass 1T Pass 1T 
______________________________________ 
COMATIVE EXAMPLE 4 
The polyester of this comparative example is formulated to a composition 
ratio of 1.25 moles of glycol to 1.00 mole of anhydride as follows (weight 
percentages based on 100% solids 99.87% of which are monomer components of 
polyester): 
______________________________________ 
1. MPDiol (Arco) monomer 22.36 
2. Trimethylopropane 
monomer 0.42 
3. 1,6-hexanediol monomer 19.79 
4. DDSA monomer 30.76 
5. Phthalic Anhydride 
monomer 32.07 
6. HHPA monomer 0.50 
7. Triphenyl phosphite 
oxidation inhibitor 
0.02 
8. Fascat 4100 catalyst 0.11 
9. Butyl Acetate solvent 11.49 
Solids charge 106.04 
Theoretical Losses 6.04 
Solids Yield 100.00 
Solution Yield 111.49 
______________________________________ 
Components 1-8 were charged while purging with inert gas. The reactor is 
slowly heated to 80.degree.-90.degree. C. to melt components; onset of 
exotherm was observed--cooling was applied as needed to maintain 
temperature below 110.degree.-115.degree. C., reaction mixture held at 
temperature for 1 hour. The reaction mixture was heated to 
220.degree.-230.degree. C. and acid value monitored until a value of 3.5 
was obtained. The reactor was cooled to 120.degree. C., and then butyl 
acetate was added: The properties of the polyester composition are as 
follows: 
______________________________________ 
Viscosity (at 85% Solids): 
Z2+ 
Non-Volatile Materials: 85.7 
Solvent: Butyl Acetate 
Color: 4- 
AV/NV (Acid Value based on Solids): 
1.6 
Weight Per Gallon (WPG): 9.03 
OHN/NV (Hydroxyl Number Based on Solids): 
97.43 
Appearance: Clear 
NV (Non-Volatile Volume): 
82.4 
______________________________________ 
The Z2+ viscosity is higher than desired and will not permit a coating 
formulation which has increased volume solids without a significant 
increase in viscosity. 
COMATIVE EXAMPLE 5 
The polyester of this comparative example is formulated to a composition 
ratio of 2.00 moles of glycol to 1.00 mole of anhydride as follows (weight 
percentages based on 100% solids 99.89% of which are monomer components of 
polyester): 
______________________________________ 
1. MPDiol (Arco) monomer 28.50 
2. Trimethylopropane 
monomer 0.53 
3. 1,6-hexanediol monomer 25.22 
4. DDSA monomer 24.50 
5. Phthalic Anhydride 
monomer 25.55 
6. HHPA monomer 0.40 
7. Triphenyl phosphite 
oxidation inhibitor 
0.02 
8. Fascat 4100 catalyst 0.09 
9. Butyl Acetate solvent 11.49 
Solids charge 104.81 
Theoretical Losses 4.81 
Solids Yield 100.00 
Solution Yield 111.49 
______________________________________ 
Components 1-8 were charged while purging with inert gas. The reactor was 
slowly heated to 80.degree.-90.degree. C. to melt components; onset of 
exotherm was observed--cooling was applied as needed to maintain 
temperature below 110.degree.-115.degree. C., reaction mixture held at 
temperature for 1 hour. The reaction mixture was heated to 
220.degree.-230.degree. C. and the viscosity and acid value were monitored 
until a value of 3.5 was obtained. The reactor was cooled to 120.degree. 
C., and then butyl acetate was added. The properties of the polyester 
composition are as follows: 
______________________________________ 
Viscosity (at 78% Solids): 
T-U 
Non-Volatile Materials: 78.3 
Solvent: Butyl Acetate 
Color: 3- 
AV/NV (Acid Value based on Solids): 
3.0 
Weight Per Gallon (WPG): 8.88 
OHN/NV (Hydroxyl Number Based on Solids): 
305.02 
Appearance: Clear 
NV (Non-Volatile Volume): 
73.7 
______________________________________ 
The resin of this example contains a significant level of low molecular 
weight polyester and/or unreacted glycol which results in a significant 
decrease of the solids level in comparison to the resins of this 
invention. The molecular weight volatile components and the resulting low 
resin solids make this resin unacceptable. 
Although the invention has thus been described in detail for the purposes 
of enablement and setting forth the best mode for carrying out the 
invention, it is to be understood variations of the invention as described 
can be made without departing from the spirit and scope of the invention 
as claimed.