LOW VISCOSITY HIGH SOLIDS PHENOPLAST COATING COMPOSITION

PRODUIT DE REVETEMENT A BASE DE PHENOPLASTIQUE A FAIBLE VISCOSITE ET A FORTE TENEUR EN MATIERES SOLIDES

English Abstract

ABSTRACT OF THE DISCLOSURE
A high solids coating composition obtained by mixing
a low viscosity dimethylol phenol, a methylene bis-phenol, an
epoxy containing reactant, a polyol and an amine catalyst all
dissolved in sufficient organic solvent to provide for easy
application but having less than 25 volume percent of solvent.

Claims

The embodiments of the invention in which an exclusive
property or privilege is claimed are defined as follows:
1. A curable coating composition having a viscosity of
between 100 and 1000 cps comprising:
(a) a normally liquid phenolic component consisting
essentially of alkyl dimethylol phenol of the structure:
<IMG>
where R is an alkyl group containing 1-16 carbon atoms
in the para or ortho position and where the methylol
groups are in the 2 remaining ortho and para positions;
(b) a phenolic component consisting essentially of an
alkylene phenol of the structure:
<IMG>
where R1 and R2 are methyl or hydrogen, x is 0, 1 or
2 and R3 is an alkyl group containing 1-16 carbon atoms;
(c) a normally liquid 1,2 - epoxy component consisting of
an aliphatic epoxy compound, an epoxy compound con-
taining aromaticity or mixtures thereof and having
an epoxy equivalent of between 130 and 200;
(d) 3-25% of the combined weight of (a), (b), (c) and (d)
of a non-volatile polyol;
19

(e) less than 25% of the combined volume of (a), (b), (c),
(d) and (e) of a non-reactive organic solvent; and
(f) an amine catalyst,
2. The composition of Claim 1 where the R3 group of
component (b) is methyl and is ortho to the phenolic hydroxy and
where the R and CH2OH groups of component (a) are para and ortho
respectively to the phenolic hydroxy.
3. The composition of Claim 2 where R1 and R2 are hydrogen.
4. The composition of Claim 3 where the component (c) is
a mixture of epoxy compounds containing aromaticity with an
aliphatic epoxy compound.
5. The composition of Claim 2 where the viscosity of the
composition is between 300 and 800 cps.
6. The composition of Claim 1 where the weight percentages
excluding solvent are 20 to 70% for the component (a); 5-60% for
component (b); 5-60% for component (c); 5-25% for component (d).
7. The composition of Claim 3 where the weight percent
composition excluding solvent is 20 to 70% component (a); 5-60%
component (b); 5-60% component (c); 10-20% component (d); and
where the viscosity of the resulting composition is between 100
and 500 cps.
8. The thermoset coating of Claim 3 cured by baking a
coated substrate at 350° - 450°F. until cured.
9. A curable coating composition having a viscosity of
between 100 and 1500 cps comprising:
(a) a normally liquid phenolic component consisting essen-
tially of alkyl dimethylol phenol of the structure:
<IMG>

where R is an alkyl group containing 1-16 carbon atoms
in the ortho or para position and where the methylol
groups are in the 2 remaining ortho and para positions;
(b) a phenolic component consisting essentially of an
alkylene phenol of the structure:
<IMG>
where R1 and R2 are methyl or hydrogen, x is 0, 1 or
2 and R3 is an alkyl group containing 1-15 carbon atoms;
(c) a normally liquid, 1,2 - epoxy component consisting of
an aliphatic epoxy compound, an epoxy compound contain
ing aromaticity or mixtures thereof and having an epoxy
equivalent of between 130 and 200;
(d) 3-25% of the combined weight of (a), (b), (c) and (d)
of a composition prepared by the partial reaction of a
hydroxy-containing polyester and an oxirane containing
compound where said composition contains both hydroxy
and oxirane groups;
(e) less than 25% of the combined volume of (a), (b), (c),
(d) and (e) of a non-reactive organic solvent; and
(f) an amine catalyst.
10. The composition of Claim 9 where the R3 group of
component (b) is methyl and is ortho to the phenolic hydroxy and
where the R and CH2OH groups of component (a) are para and ortho
respectively to the phenolic hydroxy.
21

11. The composition of Claim 10 where R1 and R2 are hydrogen,
12. The composition of Claim 11 where the weight percent
composition excluding solvent is 20 to 70% component (a); 5-60%
component (b); 5-60% component (c) where part of (c) is used in
the preparation of component (d); 5-25% hydroxy containing
polyester as component (d) at least part of which is pre-reacted
with at least part of component (c).
13. The composition of Claim 12 where component (d) is
present in an amount of 10-18%.
14. A process for depositing a coating on metal to be used
as a food container, comprising the steps of
(a) preparing a composition according to Claim 6
(b) applying said composition to the surface of metal
(c) curing said composition by baking at 350° to 450° F,
until cured
15. A process for depositing a coating on metal to be used
as a food container, comprising the steps of
(a) preparing a composition according to Claim 12
(b) applying said composition to the surface of metal
(c) curing said composition by baking at 350° to 450° F.
until cured.
22

Description

S~ii2~;
This invention relates to curable coating composi-
tions.
BACKGROUND OF THE INVENTION
.
Phenolic and epoxy resins are well known to the coat-
ings industry. In some cases, in order to obtain the best pro-
perties of each system, phenolic resins and epoxy resins are
used as mixtures, achieving thereby the most advantageous com-
'~ bination of chemical resistance and flexibility. This approachhas been used with success to provide serviceable internal
coatings for cans ~Whitehouse, Phenolic Resins, American
Elsevier 1968, p.l3~). The rigorous coating properties required
~, for this use have heretofore been met by the use of relativelyhigh molecular weight phenolic resins in admixture with high
molecular weight epoxy resins of the bis-phenol/epichlorohydrin
condensation type. These two resins are usually mixed in up
~I to approximately 75% epoxy 25% phenolic (Phenolic Resins p.28).
In order to obtain coatings systems which can be conveniently
applied by conventional techniques such as roller coating,
the resin must be of sufficiently low viscosity. For use in
the can industry, viscosities in the order of 100 - 1000 cps
are advisable. This restriction re~uires the use of significant
amounts of solvent to dissolve the high molecular weight com-
ponents, resulting in solutions of 25 - 45% solids. The use
~ of this high level of solvent is wasteful, environmentally
undesirable and expensive.
' ~ SUMMARY OF THE INVENTION
This invention involves the combination of
previously known compositions in such a manner that accept-
able coating properties are obtained from a resin solution
of higher solids than previously available. This
.
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combination involves two liquid phenolic components, a liquid
epo~y component, a polyol, a catalyst and a solvent. One
phenolic component is a low molecular weight dimethylol phenol,
The second phenolic component is a low molecular weight
S methyle~ebis phenol, The liquid epoxy component is an al~phatic
epoxy compound or an epoxy compound containing aromaticity
or mixtures thereof, The polyol is a low molecular weight,
normally liquid low viscosity compound containing at least
two hydroxy groups per molecule. The amine catalyst is one
of those catalysts known to the art for crosslinking of
phenolic/epoxy systems. These components when dissolved in
less than 25 volume percent of an organic solvent~ provide a
coating system of a viscosity compatible with currently used
application techniques while retaining the high performance
characteristics of the high molecular wei'ght, low solids systems~
DESCRIPTION OF THE PREFERRED EMBODIMENTS
_ _
In order to obtain the low viscosity of the resin
components which in turn allows a large reductiojn in the
amount of solvent necessary to obtain a system with usable
viscosity, low molecular weight components are required.
However, these components must have the ability to rapidly
gain in molecular weight during cure so that the overall cure
time is not extended beyond industry requirements and that
no sacrifice in the film properties of chemical resistence and
flexibility are produced.
One of the phenolic components (Component a) is an
oil soluble heat reactive crosslinker containing a high
concentration of alkyl dimethylol phenols of the structure:
- 2 -

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o~
HOCH2 ~1~ C~20H
(a)
R
The amine catalyzed reaction of formaldehyde and
an alkyl phenol proceeds stepwise with first the addition of
one mole formaldehydP to form a methylol phenol. A second
methylol group is then genera~ed by reaction of another mole
of formaldehyde. Additional heating will adversely cause
condensation of additonal moles of substituted phenol via
ether formation of a benzylic ether.
Since this type dimer, or higher condensation products formed by
additional etherification xeactions will have a higher viscosity
than the monomer of (a), it is desirable to have the maximum
amount of ~a) present. It is believed that the presence of
significant amounts of the dimethylol phenol must be present
in component (a) in order to obtain a coating compositi~on.
Although the viscosity can be reduced by careful selection of
the other components, the presence of the dimethylol phenol
of Structure 1 is beneficial in obtaining low viscositY. The
alkyl phenol used in the preparatlon of component (a1 may
have the alkyl substituent in ortho, meta or para position
of the phenol molecule. However, the preferred star~ing material
is the ortho or para alkyl phenol because of the easier
availablility of this material, and also the higher level of
activity of the ortho and para alkyl phenols toward condensation
with formaldehyde, The alkyl chain ~ can consist of any
configuration of 1 to 16 carbon atoms and hydrogen with the
restriction that the resultlng dimethylol phenol have low
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enough viscosity that the final composition of the invention
has a viscosity below 1500 cps. Other groups may be included
in the alkyl chain, such as ester groups, nitrile, sulfone,
either to enhance the fluidity of the composition or the properties
of the cured film. This oil soluble phenolic component is
produced by the amine catalyzed condensation of an alkyl phenol
with formaldehyde at a phenol to formaldehyde ratio of from
1.0 - 1.8 to 1~0 - 2.3. This component, while heat reactive,
will not cure by itself to give a polymer useful in the present
invention; a second ph`enolic component is necessary.
This second component (Component b) is a low molecular
weight phenol formaldehyde condensation product produced by the
reaction of USP phenol with formaldehyde or more preferably USP
phenol and an alkyl phenol with formaldehyde, where the ratio
of the phenolic reactant to formaldehyde is from 1.0 - 0.5 to
1.0 - 0.75. Although all the various possible products are
probably present in the condensation product, the product
should contain a high percentage of the mixed phenol-cresol
product shown in the structure:
OH OH
(b~ ~ R~ ~
Polycondensation should be minimized to retain low viscosity,
and the presence of both the substituted and unsubstituted
phenol in the same molecule contribute to the high desired
reactivity. ~''' of (b) may be hydrogen or alkyl. When R'''
~ is alkyl, it mayt as for Component a, consist of any configuration
; 25 of 1 to 16 carbon atoms and hydrogen. Other groups may also

5~
be incorporated into the chain, such as ester, nitrile, sul-
phone and ether, The R' " group may be ortho, meta, or para
to the phenolic hydroxy, but the usual configuration finds
the alkyl group in the ortho or para position.
The alkylene bridge may be ortho or para to the phenolic
hydroxy,` The point of attachment is controlled by the reaction
conditions during the formaldehyde phenol condensation reaction.
Acidic or base catalysis tends to cause reaction at both ortho
and para positions, while some bivalent matal~oxides or weak
acid salts of ~ivalent metal catalysts tends to favor ortho
substitution, While substitution at either position gives
applicable compounds, it has beén found that compounds having
the alkylene bridge ortho to the phenolic hydroxy gives
lower viscosity to the final coating composition.
The alkylene bridge is produced by the reaction of
aldehydes or ketones with the phenol under conditions well
known in the art. The reaction can be catalyzed by amines
or metallic hydroxides or inorganic acids. In the cases
where metallic hydroxides or inorganic acids are used, the
residual catalyst must normally be removed by was~ing the
product, since residual catalyst will cause reduced adhesion
to metal substrates especially in the presence of hot water,
It is therefore preferred to prepare co~ponent (b) with
ammonia catalyst; in this procedure the nitrogen becomes
permanently bound in the phenolic resin, but is still
available to serve in this combined form as the curing amine
catalyst for the coating composition R' and R'' of component
~b) can be hydrogen or alkyl groups with any con~iguration of 1
to 4 carbon atomsp with the restriction that the viscosity of
the resulting composition must be below 1500 cps. Other
oryanic groups may be included, such as nitrile, ester,

106SSZ~
ether, and sulfone. 4-Keto pentanoic acid ester is an
example of such an ester-containing group, leading to the
structure shown:
OH OH
C3
CH2
1, ' .
C02R
Component (b) will not cure by itself; in an admixture with
Component (a), a rapid condensation can be~obtained by the
use of an amine catalysis at elevated temperaturP. The
epoxy component (Component c) provides flexibility and en
hanced alkali resistance to the coating of this invention.
This epoxy is low molecular weight in the range of 130- 200
per epoxide group. The epoxy compound may be either aromatic,
aliphatic, or mixtures of the two types. It has been found
.
that the aliphatic low viscosity epoxy compounds give excellent
results in this invention when used alone. ExampleSof this
type of epoxy are the triglycidyl'ester of trimethylol
propane (Reichhold S~F-6~, aliphatic poly~lycidyl ether (ce-
lanese EPI-REZ~5042)* aliph~tic triglycidyl ether tCelanese
EPI-REZ 5044)l' However, inclusion of epoxy compounds containing
aromaticity have been found to increase the toughness of the
~ film and also to lower the overall cost of the epoxy component.
; ~ An example of an aromatic epoxy are the diglycidyl ethers
of bis p, p hydroxyphenyl propane (Shell Epo~ 828, Celanese
EPI-REZ 510).
The non-volatile polylol (Component d) used as a
reactive diluent, performs the dual purpose of l~wering the
viscosity of the resin prior to cure and also improves the
* Trade Marks
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flexibility of the finished cured coating, Its volatility
must be such that it will not volatize significantly at the
curing temperature, The hydroxy groups of, this polyol must,
be of sufficient reactivity to allow condensation with either
the epoxy or the phenolic components, The amounts of this
~olyol needed depends on the flexibility of the phenolic
and epoxy component selected, and may vary from 3-25 weight
percent, Representative polyols uselful as component (d) in
this invention are those shown in Table 1. Also shown in
this table ls the percentage remaining after heating the polyol
at 400F. for 10 minutes in an air circulating oven along wi~h
other property information,
TABLE I
Solids
~ 10 min, OH
Product @ 400F Value Viscosity Supplier
PCP-0300 92% 31014,5 stokes Union Carbide
2 TMP, 1 Ad~ipic
Polyester *- 80,7% 568440 stokes Ashland
Multron R 16 87.0~ 44104,1 stokes Mobay
Multron R 18 93,5~ -60147 stokes Mobay
1. Trimethylolpropane-epsilon caprolactone - Union Carbide
2, Mobay, slightly branched hydroxy tOHV 44-60) polyester
Compounds of highest interest for use as polyols are poly-
ester polyols, polyether polyols and high molecular weight
diols. Olefin oxides and epoxidized oils, since they will
perform as ~lycol anhydrides~ may also be used as the polyol.
In another embodiment of this inve!ntion, epoxy groups
and hydroxy groups may both be incorporated into the same
polymeric structure and serve as the epoxy and the polyol
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~0~S52t;
component. For example, a hydroxy-terminated polyes~er partially
reacted with an epoxy containing compound will result in a
hydroxy-epoxy containing polyester. This epoxy polyol, either
as is or mixed with additional epoxy compound, when mixed with
the phenolic components previously describecl, produces a film-
former within the scope of this invention.
Organic solvents suitable for use in this invention are
those with sufficient solvency -for the components, but with
; volatility low enough that they do not "flash" off before allow-
ing the film to level for best performance and appearance.
Alcohols such as anhydrous isopropanol, ketones such as isophorone,
esters such as butylcellosolve acetate, aromatics such as xylene
are all usable either individually or as mixtures. The solvent
is used to an extent of no more than 25 volume percent of the
organic portion of the coating, excluding fillers and water.
The solvent composition is selected so that the completely formu-
lated coating has a viscosity of between 100 and 1500 cps,
preferably between 200 and 800 cps The viscosity measurements,
unless otherwise indicated, are made using a Brookfield Viscosi-
meter ~VT, Spindle 3 at 50 rpm.
Other additives may be added to enhance the film propertiesand whose use is known to those skilled in the art, including
flow and leveling agents such as silicon resins or Modaflow*
(Monsanto). If it is found necessary to add a catalyst for
the cure, suitable amines include triethanolamine, triethylamine,
triethylenediamine and other similar amines.
EXAMPLES
Examples of the practice of this invention are Examples 1-20.
The references to the percent solids in the examples include
the water resulting from the reaction and may be lower than 80%.
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However, the non-reactive organic solvent, as a percent of
the anhydrous composition, is readily apparent from ~he formu-
lations shown.
Example 1: Preparation of phenolic Component a -
phenolic crosslinker
A. Nonyl Phenol 1125 grams
B. Paraformaldehyde 350 grams
C. 29% NH3 aqueous 35 grams
A, B and C were charged into a 2 liter pressure reactor
and heated with agitation to 120~C. under 40 lbs. pressure. At
the end of 2-1/2 hours, at 40 lhs. pressure, the reactor was
cooled at 90C. and the resin was held under 25" of vacuum until
clear, about 20 minutes.
Example 2: Preparation of phenolic Component b -
A. Ortho creso1 500 grams
B. USP Phenol 1000 grams
C. 37~ Formaldehyde 700 grams
D. 2g% NH3 aqueous 50 grams
- 500 grams of A, 500 grams of C and 30 grams of D
were charged into a three liter round bottom reaction vessel
with agitation and reflux condenser. The reactants were heated
to 100~C. and heId under reflux for 20 minutes. At the end
of 20 minutes, B was added and the remainder of C and D. The
vessel was again heated to reflux and held for two hours. At
the end of three hours, vacuum was applied and 650 mls o~ H2O
was removedO
Examples 3 - 8: Preparation of coating systems of this invention.

``` 1 t)6S52~;
MIX 3 4 5 6 7 8
_ ._ _ . . . _ _ _ _ _
Phenolic Cook
Example 1 30 20 20 15 10 12,5
Phenolic Cook
Example 2 30 40 35 35 25 30
Epoxy Resin
EPI-REZ 510* 10 10 10 10 10 10
Epoxy Resin
EPI-REZ 5042* 10 10 15 20 25 25
10PCP-0300 Polyol 5 5 5 10 15 12.5
Butyl Cellosolve
Acetate 10 10 10 10 10 10
Isophorone 5 5 5 ~ - -
Isopropanol 5 5
Silicone Resin 0.5 0.5 0.5 0.5 0.5 0.5
Triethanolamine 0.1 0.1 0.1 0~1 0.1 0.1
The above mixtures were drawn down on tin plate and
baked for 10 minutes at 400F. in an air circulating oven.
Samples 5, 6, 7 and 8 were all found to produce films with
20 excellent flexibility and good resistance to solvents such
as MEK rub. Ratio 8 was considered to be the best. It had a
viscosity of 10.3 stokes (Gardner Holt) at-77.5~ solids. Film
thickness on baked panels range from 0.1 to 1.0 mils.
Example 9: Example 9 is similar to Example 1 with the exception
that dodecyl phebol was substituted for nonyl phenol and was
run according to the following procedure:
; A. DodecyI Phenol 1060
B. 37~ Formaldehyde 700
~: C. 29~ NH3 aqueous 60
. 30 A, B and C were charged into a three liter flask
equipped with agitation and relux condenser, The reactants
were held for 4 hours at 70C. At the end of 4 hours, vacuum
was applied and 520 mls. of water were removedO
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Example 10: The phenolic component (Component a) of Example 9
was used with Component b of Example 2 as follows:
Phenolic Cook Example 9 12.5
Phenolic Cook Example 2 30
Epoxy ER-510* 10
Epoxy ER-5042* 25
PCP-0300 12.5
Butyl Cellosolve Acetate 10
L-5310* 0.5
Triethanolamine 1.0
This formulation had a viscosity of 9.1 stokes
(Gardner Holt) at 74.5% solids. The resin mixture was found
to produce a film with excellent flexibility and good MEK
rub resistance when panels were baked for 10 minutes at 400F.
Film thickness ranged from 0.1 mils, to 1.0 mil.
Example 11: Phenolic (Component a) was prepared in similar
manner to Example 1 according to the following procedure:
A. Octyl phenol 925
B. 37% Formaldehyde 700
C. 29% N~3 Aqueous 60
Components A, B and C were charged into a three
liter flask with agitation and condenser. The reactants were
heated to 65 to 70C. for 4 hours. Following the 4 hours of
reaction, the resin was cooled to 55C, and full vacuum was
applied. The resin was heated until full vacuum was reached at
70~C. yielding a clear resin.
E~ample 12: The phenolic Component a of Example 11 was formu-
lated with the phenolic of Example 2 as follows-
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Phenolic Example 11 12,5
Phenolic Example 2 30
Epoxy ER-510 10
Epoxy ER-5042 25
PCP-0300 12,5
Butyl Cellosolve Acetate 7,5
Butanol 2.5
Silicone Resin L-5310 0.5
Triethanolamine 1,0
When the formulation of Example 12 was drawn down
on tin plate, it was found to have good flexibility and good
MEK rub resistance. Viscosity 8,7 stokes at 71.2% solids,
Example 13: The phenolic (Component b) was prepared in a
manner similar to Example 2, according to the following procedure:
A. Ortho Cresol 1350
B. 37~ Formaldehyde 1300
C. 29~ NH3 aqueous 60
D. USP Phenol 1175
E. 37~ Formaldehyde 250
F, 29% NH3 aqueous 30
Components A, B and C were charged into a 5 liter
reactor and upheated. The reactants were held ~or 45 minutes
under reflux conditions with good agitation and complete con-
densate return from a reflux condenser. At the end of 45
minutes, components D, E and F were added. Again, the components
were heated to reflux and held for 2 hours followed by 1 hour
of atmospheric distîllation and then low vacuum. The resin
was finally allowed to reach 100C. under full vacuum just
~; before discharge, 1100 mls. of water were removed.
Example 14: The phenolic of ~xample 13 was formulated with the
phenolic of Example 11 as follows:
.
- 12 -

;SiS;Z~;
Phenolic Cook Example 1} 23 grams
Phenolic Cook Example 13 28 grams
PCP-0300 7.5 grams
Butyl Cellosolve Acetate 5 grams
Isophorone 5 grams
Butanol 5 grams
Triethanolamine 1,0 gram
L-5310 0,5 gram
EPI-REZ 510 7.5 grams
ER-5042 22.5 grams
This formulation had a viscosity of 7.4 stokes
(Gardner Holt) 70.1% solids~ The formulation of this example
was found to have excellent flexibility when bakes on tin plate
and good MEK rub resistance. It was run through a pasturiza-
tion test and a field usage test that consisted of being held
at 250F. for 90 minutes in contact with commercial dog food.
It passed all of the physical property requirements for an
interior can lining,
Example 15:
Phenolic Example 11 19
Phenolic Example 2 22
2 TMP, 1 Adipic polyester 9.5
Butyl Cellosolve Acetate 5
Isophorone 5
Butanol 5
Triethanolamine
Silicone Resin L-5310 0.5
EPI-REZ 510 Celanese 9.0
EPI-REZ-5042 Celanese 24
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106~iSZ~i
The ormulation of this example was drawn down on
tin plate and baked for ten minutes at 400F. Film thickness
was from 0.1 to n. 3 mils thick.
Viscosity of mix 7"8 stokes
Compatibility Good
MEK Rub on Panels 175 MEK rubs to failure
Wedge Bends and Impact
(treated with Copper Sulfate
to show flaws in film) Good
Dog Food Test (90 min.
at 250F.~ Passed - Good
Example 16:
,
Phenolic Cook Example 11 19
Phenolic Cook Example 2 22
Multron R18 ~obay) 9.5
Butyl Cellosolve Acetate 5
Isophorone 5
Butanol ~5
L-5310 0,5
Triethanolamine 1.0
,: : ,
:
~ EPI-REZ-510 9.0
. ~ .
EPI-REZ-5042 24.0
The formula~ion of this exampl~e was drawn down on
tin plate and baked for ten minutes at 400F~ Film thicknesses
were from 0~1 to 0.3 mils thick~
Test data on formulation of Example 16:
Viscosity of Mix 8.2 stokes
Compatibility of Mix Good
MEK Rubs 17 to failure
~30 Impact and Wedge Bends Good
Dog Food Test (90 min. at
250F.) Passed
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sls~;
Example 17:
Phenolic Cook Example 11 19
Phenolic Cook Example 2 22
Multron R16 (Mobay) . 9.5
Butyl Cellosolve 5
Isophorone 5
Butanol 5
L-5310 0-5
Triethanolamine 1,0
EPI-REZ-510 Celanese 9,0
EPI-REZ-5042 Celanese 24,0
The formulation of this example was drawn down on
tin plate and baked for ten minutes at 400F, Film thicknesses
were from 0.1 mils to 0.3 mils thick.
Test data for the formulation of Example 17 is as
follows:
Viscosity of Mix (Gardner Holt) 8,4 stokes
Compatibility of Mix Good
MEK Rubs 18 to failure
Wedge Bend and Impact Good
Dog Food Test (90 min. at 250FD~ Passed
Example 18: (No Polyol)
-
Phenolic Cook Example 11 19
Phenolic Cook Example 2 22
Butyl Cellosolve Acetate 5
Isophorone 5
Butanol 5
L-5310 0.5
Triethanolamine 1.0
EPI-REZ~510 9.0
,EPI-REZ-5042 24.0
,
- 15 -

-` ` lO~SZ~
The formulation of this example was drawn down on
tin plate and baked for 10 minutes at 400F~ Film thicknesses
ranged from 0 1 mils to 0.3 mils
Test data on formulation of example 18 is as follows:
Viscosity of mix S.9 stokes
Compatability of mix Good
MEK R~bs 500 to failure
Wedge bend ïmpact Good
Dog Food Test Failure
Example 19
,
Adipic acid (444 parts by weight) and ethylene glycol
(247 parts) were esterified under inert gas, and temperature o~
200C, until the polyester had an acid value of 5-10, a hydroxyl
number of 160-18~, and a viscosity of 8-16 stokes. The reaction
mixture was then cooled to 170C. and diglycidyl ether of
p,p-dihydroxydiphenylmethane (410 parts) was added. The tempera-
ture was raised to 210C., and the reaction was continued at
~ ~ this temperature until the viscosity reached 130-150 stokes and
`~ the oxirane value was 2.1-2.3. The reaction mixture was then
;~ 20 coaled to 100C.j and additional diglycidyl ether of
p,p-dlhydroxydiphenylmethane (528 parts) was added. A coating
system contalning this epoxy polyol composition was formulated
as follows:
Epoxy-polyol ~prepared in Example 19) 100 parts by weight
~; Phenolic component (a) as modified
in Example 11 51 parts
Phenolic component b 78 parts
Ethylens diamine ~7
Isophorone 2
Ethyl benzene 8
Primary amyl acetate 20
Ethyl amyl ketone 20
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~ 6S5Z~; `
Volume percent solvent in this system was 22.7, 1'his
coating, deposited on panels and baked at 204C for ten minut.es,
gave a 0.3 mil dry film. The properties of this baked ilm
were as follows:
Test Comments
_
Wedge Bend Excellent Film Integrity
at bend
Impact, Gardner, in/l b Passes 20 - front and reverse
MEK Rubs t25) No Effect
Cross Hatch Adhesion,
~ pass 100
Gloss Excellent
Hardness Excellent
Abrasion Resistance Good
Baked Film Color Good
Color Retention Fair
Solvent Re`sistance Good
24 Hr. Spot Test
Xylene No Effect
Solox* No Effect
Acetone No Effect
15% H2SO4 No Effect
20% NaOH Very Slight Effect
Example 20:
The procedure of Example 19 was followed except that
the amount of additional diglycidyl ether which was added
was 180 parts instead of 528~. The percent polyol in Example 20
is 22~. The formulation was ~he same as for Example l9o This
system was deposited on panels and baked at 204~C. for ten
; minutes, gave a 0,3 mil dry film with the following properties.
* Trade Mark
- 17 -

~6~iiS'~
Test Comment
Wedge Bend Fair to good Film Integrity
at Bend
Impact, Gardner, in/l b Passes 20 - front and reverse
MEK Rubs (25) Failure at 20 double rubs
Cross Hatch Adhesion~
~ pass 100 %
Gloss Good
Hardness Good
Abrasion Resistance Good
Baked Film Color Good
Color Retention Fair
Solvent Resistance Fair
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