Method of stabilizing the gloss retention of thermosetting resins containing hydroxyl groups

Thermosetting resins containing hydroxyl groups which can be cured with aminoplast resins are stabilized by the addition of 1,4-diazo[2,2,2]-bicyclooctane. This method is particularly useful in stabilizing the gloss retention of extensible coatings formed by curing a hydroxyl-containing urethane product with an aminoplast resin. Such coatings can be applied to virtually any solid substrate and are especially useful on rubbery, resilient substrates such as polyurethane or polyethylene foam, natural or synthetic rubber or rubber foam, and various elastomeric plastic materials. They are also particularly useful on other substrates such as mild steel or aluminum.

BACKGROUND OF THE INVENTION 
Recent advances in coating technology have provided coatings which are 
suitable for use over various substrates which are difficult to coat and 
which have many different properties. Coatings of excellent appearance, a 
high order of durability and having the ability to withstand severe 
environmental conditions have been obtained. Among the more advanced 
coatings are those employed on vehicles, such as automobiles, where good 
appearance must be maintained over long periods despite exposure to 
weather and various forms of attack during use. 
Thermosetting resins have long been useful as coating materials. Such 
compositions can be tailored to achieve a great variety of properties, 
including high strength, extensibility and durability. While such coating 
compositions have many excellent properties, a recurring problem with such 
resins, particularly thermosetting resins which are cured by aminoplast 
resins has been the instability of the cured resins resulting in a 
substantial loss of gloss over periods of time. 
SUMMARY OF THE INVENTION 
It has now been found that the addition of minor amounts of 
1,4-diazo[2,2,2]-b:cyclooctane, sometimes called triethylenediamine, to 
thermosetting resins, either before, during or after addition of the 
curing agent, unexpectedly stabilizes the gloss retention of such resins. 
The thermosetting resins of the instant invention which are stabilized by 
the secondary or tertiary amines include those resins which contain 
hydroxyl groups, and which can be cured with aminoplast resins. Examples 
of these thermosetting resins include saturated polyester polyols having 
hydroxyl values of at least about 30; hydroxyl-containing polyacrylates 
having hydroxyl values of at least about 5; polyether polyols having 
hydroxyl equivalents of at least about 100; and, polyurethane polyols 
having hydroxyl values of at least about 10. The preferred thermosetting 
resins are the polyurthane polyols. 
DETAILED DESCRIPTION OF THE INVENTION 
The compositions of the instant invention contain as one component, a 
thermosetting resin containing hydroxyl groups. Preferably, the 
thermosetting resin is a polyurethane polyol. 
The polyurethane polyols, useful in the instant invention, are produced by 
reacting a polyhydric material selcted from the group consisting of 
polyether polyols, polyester polyols and mixtures thereof, with an organic 
polyisocyanate, under conditions selected so as to produce an 
hydroxyl-containing urethane reaction product, i.e., a polyurethane 
polyol. This can be accomplished by utilizing an equivalent ratio of 
isocyanate groups in the polyisocyanate to hydroxyl groups in the 
polyhydric material of less than 1.0 and preferably 0.90 or less, and 
allowing substantially all of the isocyanate groups present to react. When 
using ratios of less than 1.0, care must be taken to avoid gelation and 
for this reason, some mono-alcohol may be necessary. In general, both the 
polyol, (i.e., material having functionality of 3 or more) content and the 
mono-alcohol content must be carefully controlled. One way to ascertain in 
any given case the amounts of polyol and mono-alcohol which should be used 
to avoid gelation is by carrying out successive tests on a small scale 
with varying proportions of components. It is, in most cases, more 
convenient to terminate the reaction at the desired stage (determined by 
viscosity), as by the addition of a compound which reacts with the 
residual isocyanate groups, thus permitting the use of higher ratios of 
isocyanate to hydroxyl (i.e., greater than 1.0). Regardless of the method 
chosen, the reaction between the polyhydric material and the 
polyisocyanate should generally be terminated when the reaction product 
has an intrinsic viscosity of 1.0 deciliters per gram or less and 
preferably 0.80 or less, since it has been found that resins with higher 
viscosities exhibit poor sprayability. It should be noted that useful 
products are provided once the reaction between the polyhydric material 
and the polyisocyanate begins although preferred products begin to be 
obtained when the intrinsic viscosity reaches about 0.05. Generally, to 
start the reaction, heat (e.g., 125.degree. F.) and catalyst (e.g., 
dibutyl tin dilaurate) may be used. The use of heat and catalyst is of 
course dependent upon the overall composition and the rate of reaction 
desired. 
In producing the desired polyurethane polyol, it is necessary that the 
polyhydric material employed possess certain properties in order to obtain 
coatings of the desired characteristics. When using a polyester polyol, 
these properties are obtained by selecting a polyether polyol, or a 
mixture of polyether polyols, having relatively long chains per hydroxyl 
group, and which thus has a hydroxyl equivalent of at least about 100 and 
preferably at least about 300. The polyether polyol component in most 
cases consists essentially of one or more diols. Triols or higher polyols 
can also be used in whole or in part, provided the polyhydric material 
contains no more than about one gram-mole of compounds having a 
functionality of 3 or more per 500 grams of the polyhydric material. While 
it is not always necessary to have a triol or higher polyol present, some 
branching is desirable, although the polyether should not be highly 
branched. There may also be present a small amount of mono-alcohol, 
particularly if larger proportions of higher polyol are used. In certain 
instances, such as where very high molecular weight polyether polyols are 
used, the polyols can be largely or even entirely made up of compounds of 
functionality higher than 2. 
Among the preferred polyether polyols are poly(oxyalkylene)glycols. 
Included are poly(oxytetramethylene)glycols, poly(oxyethylene)glycols, 
poly(oxytrimethylene)glycols, poly(oxypentamethylene)glycols, 
polypropylene glycols, etc. The preferred polyether polyols of this class 
are poly(oxytetramethylene)glycols of molecular weight between about 400 
and about 10,000. 
Also useful are polyether polyols formed from the oxyalkylation of various 
polyols, for example, glycols such as phenylene glycol, 1,6-hexanediol, 
and the like, or higher polyols, such as trimethylolpropane, 
trimethylolethane, pentaerythritol, and the like. Polyols of higher 
functionality which can be utilized as indicated can be made, for 
instance, by oxyalkylation of compounds as sorbitol or sucrose. One 
commonly utilized oxyalkylation method is by reacting a polyol with an 
alkylene oxide, e.g., ethylene or propylene oxide, in the presence of an 
acidic or basic catalyst. 
In addition to the methods indicated, the polyether polyol can be produced 
by any of the several known techniques, with the reaction conditions and 
the ratio or reactants chosen so as to provide a product having residual 
hydroxyl groups, i.e., a polyether polyol having a hydroxyl equivalent of 
at least about 100 and preferably not above about 10,000. 
Where polyester polyols are employed, the requisite properties are attained 
by selecting a polyester polyol, or a mixture of polyester polyols, which 
is formed from a polyol component having an average functionality of at 
least about 1.9 and an acid component having an average functionality of 
at least about 1.9. The polyol component in most cases consists 
essentially of one or more diols with up to about 25 mole percent of 
polyols present having 3 or more hydroxyl groups. While it is not always 
necessary to have a triol or higher polyol present, some branching is 
desirable, although the polyester should not be highly branched. Again, in 
using higher polyols, care must be taken to insure that the total amount 
of material having a functionality of 3 or more in the polyhydric material 
must be no greater than about one gram-mole 500 grams of polyhydric 
material. There may also be present a small amount of monoalcohol, 
particularly if larger proportions of higher polyols are used. In certain 
instances, such as were very high molecular weight polyols are used, the 
polyols can be largely or even entirely made up of compounds of 
functionality higher than two. 
The diols which are usually employed in making the polyester include 
alkylene glycols, such as ethylene glycol, propylene glycol, butylene 
glycol, and neopentyl glycol, and other glycols such as hydrogenerated 
bisphenol A, cyclohexane dimethanol, caprolactone diol (e.g., the reaction 
product of caprolactone and ethylene glycol), hydroxyalkylated bisphenols, 
polyether glycols, e.g., poly(oxytetramethylene)glycol, and the like. 
However, other diols of various types and, as indicated, polyols of higher 
functionality can also be utilized. Such higher polyols can include, for 
example, trimethylolpropane, trimethylolethane, pentaerythritol, and the 
like, as well as higher molecular weight polyols such as those produced by 
oxyalkylating low molecular weight polyols. An example of such a higher 
molecular weight polyol is the reaction product of 20 moles of ethylene 
oxide per mole of trimethylolpropane. 
The acid component of the polyester consists essentially of monomeric 
carboxylic acids or anhydrides having 2 to 14 carbon atoms per molecule. 
The acids should have an average functionality of at least about 1.9; the 
acid component in most instances contains at least about 75 mole percent 
of dicarboxylic acids or anhydrides. The functionality of the acid 
component is based upon considerations similar to those discussed above in 
connection with the alcohol component, the total functionality of the 
system being kept in mind. 
Among the acids which are useful are phthalic acid, isophthalic acid, 
terephthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, adipic 
acid, azelaic acid, sebacic acid, malic acid, glutaric acid, chlorendic 
acid, tetrachlorophthalic acid, and other dicarboxylic acids of varying 
types, such as lactones, tartaric acid and the like. The polyester may 
include minor amounts of monobasic acid, such as benzoic acid, and also 
there can be employed higher polycarboxylic acids, such as trimellitic 
acid and tricarballylic acid. Where acids are referred to above, it is 
understood that the anhydrides of those acids which form anhydrides can be 
used in place of the acid. It is preferred that the polyester include an 
aliphatic dicarboxylic acid as at least part of the acid component. 
While polyester polyols have been specifically disclosed, it is to be 
understood that useful products are also attainable by substituting a 
polyester amide polyol, or a mixture of polyester amide polyols, for a 
part of or all of the polyester polyol. The polyester amide polyols are 
produced by conventional techniques from the above described acids and 
diols, and minor proportions of diamines or amino alcohols, Suitable 
diamines and amino alcohols include hexamethylene daimine, hydrazine, bis 
4-aminocyclohexyl)methane, ethylene diamine, nonoethanol amine, phenylene 
diamine, toluene diamine and the like. It is to be understood that the 
polyester polyols of the instant invention include such polyester amide 
polyols. 
The polyester is produced using conventional techniques with the reaction 
conditions and the ratio of reactants chosen so as to provide a product 
having residual hydroxyl groups, i.e., a polyester polyol. The number of 
hydroxyls present in the product can be varied, but it is preferred that 
its hydroxyl value be at least about 20 and preferably more than about 50. 
The overall functionality per unit weight of the polyhydric material used 
to produce the polyurethane polyol is important. The polyhydric material 
should contain (i.e., be formed from) more than about one gram-mole of 
compounds having a functionality of 3 or more per 500 grams of the 
polyhydric material and preferably contains between about 0.01 and 0.9 
gram-moles of such compounds. By "functionality" is meant the number of 
reactive hydroxyl and carboxyl groups per molecule, with anhydride groups 
being considered as equivalent to two carboxyl groups. It is noted that 
certain compounds useful in this invention contain both hydroxyl and 
carboxyl groups; exampls include 6-hydroxyhexanoic acid, 8-hydroxyoctanic 
acid, and tartaric acid. 
While the polyether polyol or the polyester polyol may constitute the 
entire polyhydric component, mixtures of polyether polyols and mixtures of 
polyester polyols, as well as mixtures of polyether and polyester polyols, 
may be used in widely varied proportions. In addition, other 
hydroxyl-containing compounds may be added either with the polyhydric 
material to the polyisocyanate, or to the reaction mixture of the 
polyhydric material and the polyisocyanate. Such compounds include 
polyfunctional alcohols, such as 1,4-butanediol, amino alcohols, neopentyl 
glycol, trimethylolpropane, tris(hydroxyethyl) isocyanurate, 
N,N'-bis(hydroxy-ethyl) dimethyl hydantoin, and Ester Diol 204 
(2,2-dimethyl-3-hydroxypropyl-2,2-dimethyl-3-hydroxypropionate); 
carbamates of polyols, such as 0-hydroxyethylcarbamate and 
O,N-bis(hydroxyethyl)carbamate; and monohydric alcohols. Finally, other 
active hydrogen-containing compounds may be added to the reaction mixture, 
including water; polyamines such as isophorone diamine, p-methane diamine, 
propylene diamine, hexamethylene diamine, and diethylene triamine; and 
mixtures of the above-mentioned polyamines with ketones, such as 
cyclohexanone, butanone and acetone. When using polyamines and ketones, it 
is preferable to partially react the two, as by holding at room 
temperature for about one hour, before adding to the urethane reaction 
mixture, although acceptable results for some purposes are obtained by 
merely adding the amine and ketone to the reaction mixtue. 
The polyisocyanate which is reacted with the polyhydric material can be 
essentially any organic polyisocyanate, e.g., hydrocarbon polyisocyanates 
or substituted hydrocarbon diisocyanates. Many such organic 
polyisocyanates are known in the art, including p-phenylene diisocyanate, 
biphenyl diisocyanate, toluene diisocyanate, 
3,3'-dimethyl-4,4'-biphenylene diisocyanate, 1,4-tetramethylene 
diisocyanate, 1,6-hexamethylene diisocyanate, 
2,2,4-trimethylhexane-1,6-diisocyanate, methylene bis(phenyl isocyanate), 
lysine methyl ester diisocyanate, bis(isocyanatoethyl) fumarate, 
isophorone diisocyanate and methyl cyclohexyl diisocyanate. There can also 
be employed isocyanate-terminated adduct of diols, such as ethylene 
glycol, 1,4-butylene glycol, polyalkylene glycols, etc. These are formed 
by reacting more than one mole of a diisocyanate, such as those mentioned, 
with one mole of a diol to form a longer chain diisocyanate. 
Alternatively, the diol can be added along with the diisocyanate. 
While diisocyanates are preferred, higher polyisocyanates can be utilized 
as part of the organic polyisocyanate. Examples are 1,2,4-benzene 
triisocyanate and polymethylene polyphenyl isocyanate. 
It is preferred to employ an aliphatic diisocyanate, since it has been 
found that these provide better color stability in the finished coating. 
Examples include bis(isocyanatocyclohexyl) methane; 1,4-butylene 
diisocyanate, isophroone diisocyanate; and methyl cyclohexyl diisocyanate. 
The conditions of the reaction between the polyhydric material and the 
polyisocyanate are chosen so as to produce a hydroxyl-containing urethane 
reaction product, i.e., a polyurethane polyol. This can be accomplished by 
utilizing an equivalent ratio of isocyanate groups to hydroxyl groups of 
less than 1.0, controlling the polyol and mono-alcohol content as noted 
earlier, and allowing substantially all the isocyanate groups present to 
react. Alternatively, regardless of the equivalent ratio selected, a 
compound may be added to the reaction mixture, which will react with 
residual isocyanate groups and which will effectively terminate the 
reaction. Suitable compounds include water; ammonia; polyfunctinnal 
alcohols, such as ethylene glycol, aminoalcohol, tris(hydroxyethyl) 
isocyanurate, N,N'-bis(hydroxyethyl) dimethyl hydantoin, and trimethylol 
propane; monofunctional alcohols, such as n-butanol and the like; primary 
and secondary amines, such as butylamine, morpholine, allylamine and 
diethylamine; and, the hereinabove-described polyester polyols. It is 
noted that the amount of terminating agent added is such that the 
equivalent ratio of residual isocyanate groups to the isocyanate-reactive 
groups of the terminating agent is less than about one. 
In one preferred embodiment of the invention, a polyfunctional alcohol is 
used to terminate the reaction at the desired stage (determined by the 
viscosity), thereby also contributing residual hydroxyl groups. 
Particularly desirable for such purposes are aminoalcohols such as 
ethanol-amine, propanolamine, hydroxyethyl piperazine, and diethanolamine, 
since the amino groups preferentially react with the isocyanate groups 
present. Polyols, such as ethylene glycol, trimethylolpropane and 
hydroxyl-terminated polyesters, can also be employed in this manner. 
While the ratios of the components of the polyhydric material, the 
polyisocyanate and any terminating agent may be varied, it will be 
recognized by those skilled in this art that the amounts of the components 
shoudl be chosen so as to avoid gelation and so as to produce an ungelled, 
urethane reaction product which contains hydroxyl groups. The hydroxyl 
value (as deteermined ab ASTM Designation E 22-67, Method B) of the 
urethane reaction product should be at least 10 and in most cases is 
between about 20 and about 200. 
The polyester polyols and the polyether polyols described above may 
themselves be used as the thermosetting resin component of the instant 
invention. When used by themselves, some material of functionality of 3 or 
more must be present in order to provide good films. Thus, the polyester 
or the polyether shall contain (i.e., be formed from) at least about 0.01 
and not more than about one gram-mole of compounds of functionality of 3 
or more per 500 grams of the reactants used to produce the polyester 
polyol or the polyether polyol. 
The polyester polyols, polyether polyols, polyurethane polyols and the 
methods of manufacture thereof are more fully described in U.S. 
application Ser. Nos. 828,337, filed May 27, 1969, now abandoned; U.S. 
Ser. No. 839,648, filed July 7, 1969, now abandoned; U.S, Ser. No. 
313,060, filed Dec. 7, 1972, now abandoned; U.S. Ser. No. 347,022 filed 
Apr. 2, 1973, now abandoned and U.S. Ser. No. 361,010 filed May 16, 1973, 
now abandoned. 
Also useful as the thermosetting resin are hydroxyl-containing 
polyacrylates having values of from 5 to 200. The preferred polyacrylates 
are those containing hydroxyl groups derived from monoacrylates or 
methacrylates of a diol such as hydroxyalkyl esters in which the alkyl 
group has up to about 12 carbon atoms, such as acrylic acid and 
methacrylic acid esters of ethylene glycol and 1,2-propylene glycol. 
Examples include hydroxylethyl acrylate and methacrylate and 
hydroxylpropyl methacrylate as well as polyethylene glycol monoacrylate 
and polycaprolactone monoacrylate. Other useful hydroxyalkylesters include 
hydroxybutyl acrylate, hydroxyoctyl methacrylate, glyceryl acrylate, and 
the like. 
The aminoplast resin used to cure the thermosetting resins may be any 
aldehyde condensation product of melamine, urea, and similar compounds; 
products obtained from the reaction of formaldehyde with melamine, urea or 
benzoguanamine are most common and are preferred herein. However, 
condensation products of other amines and amides can also be employed, for 
example, aldehyde condensates of triazines, diazines, triazoles, 
guanidines, guanamines and alkyl and aryl-substituted derivates of such 
compounds, including alkyl and aryl-substituted ureas and alkyl and aryl 
substituted melamines. Some examples of such compounds are 
N,N'-dimethylurea, benzourea, dicyandiamine, formoguanamine, 
acetoguanamine, ammeline, 2-chloro-4,6-diamino-1,3,5-triazine, 
6-methyl-2,4-diamino-1,3,5-triazine, 3,5-diamino-triazole, 
triaminopyrimidine, 2-mercapto-4,6-diamino-pyrimidine, 2,4,6-triethyl 
triamino-1,3,5-triazone, and the like. 
While the aldehyde employed is most often formaldehyde, other similar 
condensation products ca be made from other aldehydes, such as 
acetaldehyde, crotonaldehyde, acrolein, benzaldehyde, furfural, and 
others. 
The aminoplast resins contain methylol or similar alkylol groups, and in 
most instances at least a portion of these alkylol groups are etherified 
by a reaction with an alcohol to provide organic solvent-soluble resins. 
Any monohydric alcohol can be employed for this purpose, including such 
alcohols as methanol, ethanol, propanol, butanol, pentanol, hexanol, 
hepanol and others, as well as benzyl alcohol and other aromatic alcohols, 
cyclic alcohol such as cyclohexanol, monoethers of glycols such as 
Cellosolves and Carbitols, and halogen-substituted or other substituted 
alcohols, such as 3-chloropropanol. The preferred amine-aldehyde resins 
are substantially etherified with methanol or butanol. 
The amounts of individual components in the coating compositions of this 
invention can be varied over a wide range. Preferably, however, the 
compositions contain from 5 to about 50 percent by weight of the 
aminoplast resin, and from about 0.01 to about 5 percent by weight of the 
1,4-diazo[2,2,2]-bicyclooctane. It has been found that 
1,4-diazo[2,2,2]-bicyclooctane contents greater than about 5 percent give 
no added advantage although acceptable results are obtained therefrom. 
The aminoplast is combined with the thermosetting resin and may be used 
with or without known catalysts. The resin is then cured by heating. 
Generally the resin is heated to about 140.degree. to 400.degree. F. for 1 
to 60 minutes to cure. The 1,4-diazo[2,2,2]-bicyclooctane may be added 
either before, during or after the addition of aminoplast resin. 
For optimum properties when the thermosetting resin is a polyurethane 
polyol, for many purposes it is prefered to include in the composition a 
polymeric polyol having a low glass transition temperature, i.e., having a 
glass transition temperature below about 25.degree. C. The inclusion of 
such a polymeric polyol gives a balance of flexibility and hardness. Among 
the preferred polymeric polyols are polyether polyols; especially 
preferred are poly(oxyalkylene)glycols such as polyethylene glycol, 
polypropylene glycol, and other such glycols having up to about 6 carbon 
atoms separating each pair of eoxygen atoms. A specific preferred polyol 
is poly(oxytetramethylene)glycol. Other highly desirable polyols are 
polyester polyols having the desired glass transition temperature, 
especially those produced from acyclic reactants such as adipic acid and 
azelaic acid and alkylene glycols; poly(neopentyl adipate) is a useful 
example. Still other polymeric polyols of suitable properties include 
condensates of lactones with polyols, such as the product from 
caprolactone and ethylene glycol, propylene glycol, trimethylolpropane, 
etc. 
The polymeric polyol can be incorporated into the composition in various 
ways. In some instances, the polyhydric material employed can serve as the 
polymeric polyol, but this does not usually provide a coating of suitable 
hardness. More usually, the "soft" polymeric polyol is used in conjunction 
with a polyhydric material (or constituent thereof) having a higher glass 
transition temperature. One method is to include the polymeric polyol in 
the polyhydric material as part of the polyol componet; another way is to 
produce an isocyanato-terminated adduct or prepolymer from the polymeric 
polyol and the polyisocyanate; a third method is to blend the polymeric 
polyol as such with the polyhydric material, before or after the 
polyhydric material is reacted with the polyisocyanate; alternatively the 
polymeric polyol can be blended with the aminoplasts before addition to 
the reaction product. The choice of method depends upon the particular 
components used and the properties desired, but in each instance the 
product contains both "hard" and "soft" segments in a type of block 
copolymer in the cured coating. 
The proportions of the above components can be varied to provide certain 
properties. For example, higher levels of polymeric polyol result in 
somewhat softer and more extensible coatings, whereas harder, more 
resistant coatings are obtained by increasing the proportion of aminoplast 
resin. The amount employed depend in large part upon the nature of the 
particular components, e.g., the specific polyhydric material, aminoplast 
resin, as well as the type of polymeric polyol, if any, employed. 
In addition to the componets above, the compositions ordinarily contain 
other optional ingredients, including varius pigments of the type 
ordinarily utilized in coatings of this general class. In addition, 
various fillers, plasticizers, anti-oxidants, flow control agents, 
surfactants and other such formulating additives are employed in many 
instances. The composition is ordinarily contained in a solvent, which can 
be any solvent or solvent mixture in which the materials employed are 
compatible and soluble to the desired extent. Acid catalysts and other 
curing catalysts can be added to aid in curing if desired; these can 
permit the use of lower temperatures and/or shorter times. When using such 
catalysts, it has been found that small amounts of alcohol (e.g. 
isopropyl, butyl, and the like) are generally needed to stabilize the one 
package system. 
The composition herein can be applied by any conventional method, including 
brushing, dipping, flow coating, etc., but they are most often applied by 
spraying. Usual spray techniques and equipment are utilized. They can be 
applied over virtually any substrate, including wood, metals, glass, 
cloth, plastics, foams, and the like. 
The invention will be further described in connection with several examples 
which follow. These examples are given as illustrative of the invention 
and are not to be construed as limiting it to their details. All parts and 
percentages in the examples and throughout the specification are by weight 
unless otherwise indicated.

EXAMPLE I 
A polyester polyol was prepared by charging a reaction vessel with the 
following: 
______________________________________ 
Parts by Weight 
______________________________________ 
Neopentyl glycol 2880 
Adipic acid 1640 
Trimethylolpropane 503 
Isophthalic acid 2800 
______________________________________ 
The mixture was heated from 180.degree. to 250.degree. C. until a total of 
about 1000 parts of water had been removed, and the resin had an acid 
value of about 6. The resin was then thinned with 3200 parts of 
methylbutyl ketone to give a resin with an acid value of about 4.2 an 
hydroxyl value of about 56 at 67 percent solids and a Gardner-Holdt 
viscosity of Q+. 
A reaction mixture was formed using the polyester polyol so produced by 
blending the following: 
______________________________________ 
Parts by Weight 
______________________________________ 
Polyester polyol 9300 
Methane-bis (cyclohexyl isocyanate) 
695 
(Hylene W) 
Methyl butyl ketone 1500 
______________________________________ 
The mixture was heated at 80.degree. C. for 10 hours after which time 16.1 
parts of monethanolamine, 330 parts of butyl alcohol and 775 parts of 
isopropyl alcohol were added to terminate the reaction. The resin had an 
acid value of about 3.7 at 55 percent solids. 
A white coating was then formulated by blending the following: 
______________________________________ 
Parts by Weight 
______________________________________ 
Polyurethane polyol 184 
Butylated melamine foramaldehyde resin 
78 
Cellulose acetate-butyrate 
20 
Polyester resin.sup.*1 
Antioxidant (Santowhite, available from 
Monsanto) 4.0 
UV absorber (Tinuvin 328, available from 
Eastman Kodak) 4.0 
p-Toluene sulfonic acid 1.0 
Diethylamine 0.6 
Silicone oil surfactant (SF 1023, available from 
General Electric) 3.0 
Butyl alcohol 44 
Methylisobutyl ketone 132 
Pigment paste.sup.*2 
______________________________________ 
.sup.*1 The polyester resin used was composed of 670 parts of neopentyl 
glycol, 468 parts of trimethylolpropane, 705 parts of sebacic acid, 870 
parts of isophthalic acid, and 19 parts of hydroxyethylethylenimine. 
.sup.*2 The pigment paste is prepared by dispersing 19.0 parts of the 
polyester described in *1, 61.5 parts of titanium dioxide and 19.5 parts 
of isobutyl acetate in a Zircoa mill. 
The above coating formulation was used as a standard coating to which were 
added various amines to test their effect on gloss retention of the cured 
coatings as follows: 
______________________________________ 
Percent Added 
______________________________________ 
Triethylenediamine 0.05 
Triethylenediamine 0.5 
Triethylenediamine 1.0 
______________________________________ 
The above coatings were then spray applied to metal and to a microcellular 
urethane foam, and cured for 30 minutes at 250.degree. F. 
In each instance, the amine stabilizer greatly increased the gloss loss 
stability of the coated film. 
EXAMPLE II 
A polyester polyol is prepared by charging a reaction vessel with the 
following: 
______________________________________ 
Parts by Weight 
______________________________________ 
Neopentyl glycol 126.9 
Trimethylolpropane 22.1 
Adipic acid 72.3 
Isophthalic acid 123.2 
______________________________________ 
This mixture was heated to 220.degree. C, with removal of water until the 
resin had a Gardner-Holdt viscosity of F (60 percent solids in methyl 
ethyl ketone), an acid value of about 10 and a hydroxyl value of about 
100. A reaction mixture was formed using the polyester polyol so produced 
by blending the following: 
______________________________________ 
Parts by weight 
______________________________________ 
Polyester 70 
Methyl ethyl ketone 35 
Methane-bis (cyclohexyl isocyanate) 
7.13 
Triethylene diamine 0.39 
______________________________________ 
This mixture was held at 47.degree. C for 11 hours and then at 67.degree. 
C. for 5 more hours. There were then added 22 parts of n-butanol and 0.3 
part of ethanolamine. The product had a Gardner-Holdt viscosity of Z1-Z2, 
a non-volatile solids content of about 60 percent and an acid value of 
3.7. 
A white coating composition was formulated using the urethane reaction 
product thus produced by blending the following: 
______________________________________ 
Parts by Weight 
______________________________________ 
Urethane reaction product 
140 
Butylated melamine formaldehyde resin 
39 
Poly(oxytetramethylene)glycol 
10 
p-Toluene sulfonic acid 0.4 
Silicone oil surfactant (SF 1023) 
4 
Pigment paste* 8.2 
Methyl isobutyl ketone 52 
*The pigment paste employed was made in a solution of the above described 
urethane reaction product by blending the following: 
Parts by Weight 
______________________________________ 
Urethane reaction product 
25 
TiO.sub.2 55 
Cellosolve acetate 
Methyl isobutyl ketone 
10 
Butanol 10.5 
______________________________________ 
A coating composition was formulated utilizing the same polyurethane 
polyol, but without the use of the triethylene diamine stabilizer. Both 
composition were then coated on a substrate and heated at 250.degree. F. 
for 60 minutes. The two films were then tested for stability to gloss loss 
in a weatherometer after Florida exposure, with the resulting being 
tabulated below: 
______________________________________ 
Initial 3 6 9 12 18 
Coating Gloss (20.degree.) 
Mos. Mos. Mos. Mos. Mos. 
______________________________________ 
With Stabilizer 
87 72 56 55 38 21 
Without Stabilizer 
68 51 40 40 33 15 
______________________________________ 
As can be readily seen from the above results, the use of the 
triethylenediamine stabilizer greatly increased the gloss loss stability 
of the coated films. 
EXAMPLE III 
Two coating composition, similar to those formulated in Example I, except 
that a medium blue metallic paste was substituted for the TiO.sub.2 paste 
therein, were applied to a substrate and heated at 250.degree. F. for 60 
minutes. The two films were then tested for stability to gloss loss in a 
weatherometer after Florida exposure, with the resulting being tabulated 
below: 
______________________________________ 
Initial 
Coating Gloss (20.degree.) 
3 Mos. 6 Mos. 
______________________________________ 
With stabilizer 
82 60 44 
Without stabilizer 
80 45 34 
______________________________________ 
As can be seen from the above results, the use of the triethylene diamine 
stabilizer increased the gloss loss stability of the coated film. 
EXAMPLE IV 
The following were charged to a reaction vessel: 
______________________________________ 
Parts by Weight 
______________________________________ 
Polycaprolactone diol (reaction product 
of caprolactone and diethylene glycol; 
molecular weight - 1250) 
1170 
Methylbutyl ketone 500 
Methane-bis (cyclohexyl isocyanate) 
560 
Triethylenediamine 9.4 
______________________________________ 
The mixture was heated and held at 120.degree. C. for about 1 hour. Ninety 
parts of trimethylol propane and a homogeneous mixture of 88 parts of 
isophorone diamine and 176 parts of cyclohexanone were then added to the 
reaction mixture. 
After about four and one-half hours at 95.degree. C., 15 parts of 
monoethanolamine, 98 parts of n-butanol and 294 parts of isopropanol were 
added to terminate the reaction. The resultant urethane resin had an acid 
value of 0.34, and a Gardner-Holdt viscosity of Z5-Z6. 
A coating composition was then formulated by blending the following : 
______________________________________ 
Parts by Weight 
______________________________________ 
Urethane reaction product 
153 
Melamine resin 31 
p-Toluene sulfonic acid 
1 
Pigment paste* 90 
Silicone oil surfactant (SF 1023) 
4 
Silicone slip agent (DC 200, available 
from Dow-Corning) 1 
Isopropanol 48 
Tinuvin 328 1 
*The pigment paste was employed made in a solution of the above-described 
urethane reaction product by blending the following: 
Parts by Weight 
______________________________________ 
Urethane reaction product 
25 
TiO.sub.2 55 
Cellosolve acetate 10 
n-butanol 10 
______________________________________ 
A second coating composition was formulated, without the use of the 
triethylenediamine stabilizer. Both compositions were then coated on a 
substrate and heated at 250.degree. F. for 30 minutes. The two films were 
then tested for stability to gloss loss in a weatherometer after Florida 
exposure, with the results being tabulated below: 
______________________________________ 
Initial 3 6 9 12 18 
Coating Gloss (20.degree.) 
Mos. Mos. Mos. Mos. Mos. 
______________________________________ 
With stabilizer 
90 61 39 38 34 19 
Without stabilizer 
73 8 6 4 3 2 
______________________________________ 
EXAMPLE V 
As can readily be seen from the above results, that the use of the 
triethylenediamine greatly increases the gloss loss stability of the 
coated films. 
Two coating compositions, similar to those of Example IV, except that a 
medium blue pigment is substituted for the TiO.sub.2 paste therein, were 
applied to a substrate and heated at 250.degree. F. for 60 minutes. The 
two films were then tested for stability to gloss loss in a weatherometer 
after Florida exposure, with the results being tabulated below: 
______________________________________ 
Initial 3 6 9 12 
Coating Gloss (20.degree.) 
Mos. Mos. Mos. Mos. 
______________________________________ 
With stabilizer 
87 51 26 23 13 
Without stabilizer 
77 19 10 7 4 
______________________________________ 
As can be readily seen, the use of triethylene diamine greatly increases 
the gloss loss stability of the coated films. 
In a similar manner, coating compositions of desirable properties are 
attainable by using other tertiary and secondary amines, as set forth in 
the specification. 
According to the provisions of the Patent Statutes, there are described 
above the invention and what are now considered to be its best 
embodiments. However, within the scope of the appended claims, it is to be 
understood that the invention can be practiced otherwise than as 
specifically described.