Note: Descriptions are shown in the official language in which they were submitted.
~1~719~
1 ; This invention relates to drier systems for surface-
2 ' coating compositions that contain oxidizable organic film-forming
3 ~ resinous vehicles and to surface-coating compositions that
4 ,. contain these drier systems.
i Metal salts of organic acids have long been used in
6 ~i surface-coating compositions that contain drying oils and other
7 , oxidizable organic vehicles to accelerate the drying process and
8 1`' to promote the polymerization of the unsaturated oils to dry,
g l¦mechanically-resistant coatings. The drier systems most commonly
o l¦used contain a primary or active drier and a secondary or
Il ¦auxiliary drier. The active driers are strong oxidants that bring
12 1¦ about rapid top dry of the film but have little or no effect on
13 ll through-dry. The auxiliary driers do not by themselves promote
~4 ,¦ drying, but when used in conjunction with an active drier they
~5 ¦promote drying throughout the film and contribute hardness or
16 1l flexibility to the dry film.
17 ¦¦ Until recently, lead was the most widely-used auxiliary
18 ¦~ drier for surface-coating compositions. Because government
19 ~! regulations now require that surface-coating compositions to be
20 1¦ used as residential paints contain not more than 0.06% lead, it
21 ~¦ has become necessary to develop drier systems that are as
22 ill effective as those that contain lead, but do not contain lead or
23 ~ other very toxic materials.
24 i-i, Among the drier systems that have been developed as
25 ,~ replacements for lead-containing systems are those that use
26 ~ zirconium and/or calcium as the auxiliary drier. Such systems
27 i~ were disclosed by Mack et al. in U.S. patent 2,739,902~ by
28 ~ &ottesman et al. in U.S. patent 3,901,837, and by Burger in
29 ~, "Treatise on Coatings"~ Volume 4, "Formulations", (Marcel Dekker,
30 Inc., New York, 1975) pages 557-568. These replacement drier
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i! :
~ ~¦systems generally give good results in coating compositions that
2 I!are intended for interior use or for exterior use under moderate
3 1 weather conditions. They are not satisfactory as replacements
4 ~ for lead-containing drier systems in housepaints that contain an
s ¦ oxidizable resinous binder, such as linseed oil, and that are to
6 ¦ be applied under adverse weather conditionsg for example~ at
7 temperatures not higher than 50Fo (10C.) and relative humidities¦
above 50%~ Such conditions occur, for example, in the northern
¦portions of the United States during the autumn months. Under
o ¦these conditions, surface-coating compositions that contain as
l ¦driers cobalt and zirconium and/or calcium do not air dry in
2 ¦ 24 hours.
13 ¦ In accordance with this invention, it has been found that
14 ¦surface-coating compositions that contain a drier system in which
15 ¦the auxiliary drier comprises bismuth are comparable to the
6 corresponding compositions that contain conventional drier systems 1
17 in which the auxiliary drier is lead in both drying time and film ¦
18 properties when air dried under either favorable or adverse
19 environmental conditions. The surface-coating compositions of
20 this invention, however 9 do not contain any components that are
21 nown to be very toxic.
Z2 Bismuth salts of organic acids and their use as driers for
23 urface-coating compositions are known in the art. For example,
24 ismuth salts of alkylated salicylic acids were disclosed by
ruson in U.S. patent 1,933, 520 as being useful as driers,
26 articularly in marine coatings where they also serve as repellents,
27 f marine organisms. Meidert et al. in U.S. patent 2,251,798
28 isclosed a number of polyvalent metal salts of branched-chain
29 arboxylic acids obtained by alkaline oxidation of primary alcohols,
30 t elevated temperatures and pressures and reported that these
- 4 - ~,
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salts aTe useful as driers for varnishes and lacquers. The bismuth salt
was ssid to be less suitable than, for e~ample, the cobalt, lead, and zinc
salts because of its high cost. Processes for the production of bismuth
salts of various organic acids were disclosed by Bruson in United States
Patent 2,044,968, by Considine in United States Patent 3,211,768 and by
Cukor et al. in United States Patent 3,962,298.
According to one aspect of the present invention, there is
provided a surface-ceQting composition that air dries in 24 hours or less
at temperatures not higher than 50F. and relative humidities ~bove 50%
that comprises an oxidizable, organic, film-forming resinous vehicle; an
active drier metal; an auxiliary drier metal; and an inert non-polar
organic solvent, 0.02% to 0.2%, based on the weight of vehicle solids, of
said active drier metal selected from the group consisting of cobalt,
manganese, iron, cerium and other lanthanides, and mixtures thereof being
present in said surface-coating composition; and 0.05% to 0.50%, based
on the weight of vehicle solids, of auxiliary trier metal that contains
10% to lO0~ by weight of bismuth and 0 to 90% by weight of a metal selected
from the group consisting of calcium, barium, zinc, zirconium, lead, and
mi~tures thereof being also present in said surface-coating composition,
said active and auxiliary drier metals being present in the surface-coating
composition as salts of acids selected from the group consisting of aliphatic
monocarboxylic acids having 6 to 22 carbon atoms, cycloaliphatic monocar-
boxylic acids having 6 to 10 carbon atoms, and mixtures thereof, and said
composition containing a larger percentage by weight of said auxiliary
drier metal than said active drier metal.
According to another aspect of the present invention there
is provided a d~ier system for surface-coating compositions that contain
oxidizable, organic, film-forming resinous vehicles and that air dry in 24
hours or less at temperatures not higher than 50F. and relative humidities
3Q above 50% that comprises a metal salt component containing
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a) an active drier metal selected from the group consisting
of cobalt, manganese, iron, cerium and other lanthanides, and mixtures
thereof;
b) an auxiliary drier metal that contains 10% to 100% by
weight of bismuth and 0 to 90% by weight of a metal selected from the group
consisting of calcium, barium, zinc, zirconium, lead, and mixtures thereof,
said actiYe and auxiliary drier metals being present as salts of acids
selected from the group consisting of aliphatic monocarboxylic acids
having 6 to 22 carbon atoms, cycloaliphatic monocarboxylic acids h~ving 6
to 10 carbon atoms, and mixtures thereof; and an inert, non-polar organic
solvent wherein said drier system contains a larger precentage by weight
of said auxiliary drier metal than said active drier metal.
According to further aspect of the present invention there
is provided an auxiliary drier metal composition for use in drier systems
that is a solution of a metal salt component in an inert, non-polar organic
solYent, said metal salt component containing 10~ to 100~ by weight of
bismuth and 0 to 90% by weight of a metal selected from the group consisting
of calclum, barium, zinc, zirconiumJ lead, and mixtures thereof, said
metals being present as salts of acids selected from the group consisting
of aliphatic monocarboxylic acids having 6 to 22 carbon atoms, cycloali-
phatic monocarboxylic acids having 6 to 10 carbon atoms, and mixtures
thereof.
Preferably the surface-coating compositions of this invention
comprise an oxidizable organic film-forming resinous vehicle, 0.02% to 0.1%,
based on the weight of vehicle solids of
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an active drier metal such as cobalt, manganese, iron, cerium and other
lanthanides, and mixtures thereof, and 0.05% to 0.50%, based on the weight
of vehicle solids, of auxiliary drier metal that contains 10% to 100% by
weight of bismuth and 0 to 90% by weight of calcium, barium, zinc, zirconium,
lead, or a mixture of these metals. When the auxiliary drier metal is a
mixture of bismuth and lead, the amount of lead in the surface-coating
composition must be less than the maximum permitted by government regulations.
The surface-coating compositions preferably contain 0.04% to 0.08% of an
active drier metal and 0.05% to 0.20% of one of the aforementioned suxiliary
drier metals. Particularly advantageous results have been obtained when
the surface-coating composition contained 0.04% to 0.08% of cobalt and
either 0.05% to 0.15% of bismuth or a mixture of 0.05% to 0.10% of bismuth
and 0.02% to 0.10% of calcium, all percentages being based on the weight of
resinous vehicle solids.
The active and auxiliary drier metals are incorporated into the
drier systems as oil-soluble metal salts or branched-chain or straight-chain
aliphatic monocarboxylic acids having 6 to 22 carbon atoms, cycloaliphatic
monocarboxylic acids having 6 to 10 carbon atoms, or mixtures of these acids.
Illustrative of these
f'~ -5b-
~J"
7:~97
1 ,~acids are 2-ethylbutanoic acid, 2,2-dimethylpentanoic acid,
2 ~ 2-ethylpentanoic acid, 2-ethyl-4-methylpentanoic acid, 2-ethyl-
3 ~', hexanoic acid, isooctanoic acid, isononanoic aicd, neononanoic
4 ~' acid, isodecanoic acid, neodecanoic acid, 2-ethyldecanoic acid,
5 ,1 isotridecanoic acid, isotetradecanoic acid, n-octanoic acid,
6 If n-dodecanoic acid, cyclopentanoic acid, methycyclopentanoic acid,
7 1~ cyclohexanoic acid, methylcyclohexanoic acid, 1,2-dimethylcyclo-
8 i! hexanoic acid cycloheptanoic acid 9 and the like. The preferred
g lacids for use in the preparation of the metal salts are the
30 llbranched_chain aliphatic monocarboxylic acidshaving8 to 18 carbon
atoms9 such as 2-ethylhexanoic acid, isooctanoic acid, 292-diethyll
2 ~I hexanoic acid, 2-methyl-2-ethylheptanoic acid, 2,2-dimethyloctanoic
13 ~ acid, 2-propylheptanoic acid, 3,5,5-trimethylhexanoic acid, 3-
14 ¦ethyloctanoic acid, isononanoic acid, isodecanoic acid, isododeca-
5 ¦ noic acid, 2-ethyldodecanoic acid, and tall oil fatty acids; naph-
6 ¦ thenic acids, such as cyclopentanoic acid, cyclohexanoic acid,
17 1 cycloheptanoic acid, and methylcyclohexanoic acid; and mixtures of
18 , these acids. Particularly preferred acids include 2-ethylhexanoic
19 1 acid, isononanoic acid, isodecanoic acid, and mixtures thereof.
20 ~ The surface-coating compositions of this invention can be
Zl ¦ prepared by incorporating in the compositions the appropriate
22 ¦jamounts of the metal salts, mixtures of the metal salts, or solu-
23 ¦¦ tions containing one or more of the metal salts. They are prefer-
24 l¦ably prepared by incorporating in the surface-coating composition
25 llfrom 0.02% to 5%, based on the weight of the vehicle, of a drier
26 f~ system that is a metal salt solution containing the required
27 l¦amounts of active drier metal and auxiliary drier metal. These
28 Idrier solutions generally contain 1% to 16% by weight of active
29 1I drier metal that is cobalt, manganese, iron 9 cerium, and other
30 ~llanthanides, or a mixture thereof and 6% to 36% by weight of
31 !~auxiliary drier metal that contains from 10% to 100% by weight of
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¦Ibismuth and 0 to 90% by weight of calcium, barium, zirconium, zinc,~
lead, or a mixtur~ thereof. The drier systems preferably contain
1l5% to 7% by weight of cobalt or another active drier metal and 18%
4 I to 30% by weight of an auxiliary drier metal that contains 50% to
1100% by weight of bismuth and 0 to 50% by weight of calcium.
6 I The novel drier systems are solutions of the metal salts
7 1 in an inert non-polar organic solvent that is preferably a hydro-
8 carbon or a halogenated hydrocarbon~ The preferred solvents
9 include aliphatic and cycloaliphatic hydrocarbons such as hexane,
o heptane 7 octane, isooctane, cyclohexane, and cycloheptane;
1~ petroleum distillates such as mineral spirits9 gasoline, diesel
12 fuel, and fuel oils; aromatic hydrocarbons such as benzene,
13 toluene, xylenes, and ethylbenzenes; and chlorinated compounds
14 such as chlorobenzenes, carbon tetrachloride, and ethylene
dichloride. Particularly preferred as the solvent in the drier
16 systems is mineral spirits that is not photochemically reactive
17 ¦as defined in Section (K) of Rule 66 of the County of Los Angeles
¦Air Pollution Control District and that has a distillation range
19 1f about 150 to 200C.
20 ¦ The drier systems may also contain an additive that
21 ¦decreases their viscosities. Such additives include the
22 alkyl acid phosphates described in U.S. patent No. 2,4~6,824 ,
23 and the polyoxyalkylene glycols described in U.S. patent
24 1 No. 2,807,553.
The drier systems of this invention can be used to
26 accelerate the drying rate of a wide variety of surface-coating
27 systems including paints, varnishes, enamels, printing inks, and
28 the like that contain an oxidizable organic film-forming resinous
29 ¦ vehicle. The vehicle may be a drying oil or a semi-drying oil,
30 ~¦such as linseed oil, soybean oilg tung oilg or dehydrated castor
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l l
1 lloil in the raw, blown, or heat-bodied form. Alternatively, it
2 ll may be an alkyd resin or an oleoresinous varnish.
3 '11 In addition to the oxidizable organic film-forming
4 i~ resinous vehicle and the drier system, the surface-coating
¦¦compositions may contain pigments, dyes, extenders, solvents,
6 ¦ plasticizers, antiskinning agents, fungicides, and other additives
7 ~in the amounts ordinarily used in such compositions. Illustrative
8 of the pigments that are used in surface-coating compositions are I
g titanium dioxide, iron oxide, ~nc oxide, antimony
o oxide, kaolin, china clay, calcium carbonate, silica, talc, zinc
~l chromate, carbon black, and mixtures thereof. The useful solvents
12 include benzene, toluene, xylene, naphtha, mineral spirits, hexane,
13 isooctane, and petroleum ether as well as water for water-based
14 ¦ surface-coating compositions.
I The invention is further illustrated by the following
16 ¦ example~:
17 ¦ Examples 1 and 2
18 ¦ A house paint was prepared by grinding the ~ollowing
19 ¦materials together in a pebble mill:
20 ¦ Parts by Weight
2I ¦ Titanium Dioxide (Type IV) 6.90
22 ¦ Brown Iron Oxide (Class III) 6.90
23 ~ Iron Oxide (Class I)0.40
24 Calcium Carbonate 6.90
25 ¦ Silica and Silicates3.90
26 Soya Alkyd Resin 17.55
27 ! Q-Bodied Linseed Oil 5.25
28 ¦~ Neutral Linseed Oil10.50
29 ¦ Bodied Linseed Oil 2.25
30 ii Ester Gum 4.74
il (continued)
7~97
,.,
Parts by Weight
B 1 Fungicide (FUNGITE~OL 11) 0o51
3 1li Mineral Spirits 34.20
4 ¦I To portions of the paint were added either a drier system `
5 ¦¦ of this invention or a comparative drier system.
6 !I The drying times of the house paints were measured on
¦~ 2 mil wet films at 70F. (21C`) and 50% relative humidity and
8 ¦ at 50F. (10C.) and 60% relative humidity using Improved Gardner
9 ¦ Circular Dry Time Recorders. The drier systems used and the
o j results obtained are given in the table that follows:
¦ Table
2 ~ Drier System (% Metal Based on Vehi~le Solids)
Comparative
14 ¦ ~ - ExamplesExamples
15 ~
Cobalt 2-ethylhexanoate0.0450.045 0.045 0.045
16 Cobalt isononanoate
f
17 Bismuth 2-ethylhexanoate 0.10 0.07 _
18 Bismuth isononanoate
Calcium 2-ethylhexanoate _ 0.03 _ 0.075
Calcium isononanoate
Lead 2-ethylhexanoate _ 0.45
21 Lead isononanoate
Zirconium 2-athylhexanoate _ _ _ 0.20
22 Zirconium isononanoate
23
24 Drying Time (Hours:Minutes)
at 70F. (21C.~50%9 30 8-30 8 00 9.45
26 Relative Humidity . . . f
at 50F. (10C.)/60%19:00 18:15 16:00 >24:00
27 ¦ Relati~re Humidity
28 ~ _ 't
29 ~ t~ ~k
. '~
` ~lS7~ 97
1 ~ From the data in the table, it will be seen that all of
2 ,', the drier systems were effective when the paints were air-dried
3 ¦ under favorable conditions (70F./50% relative humidity). When
4 1~ the paints were dried under adverse weather conditions (50F./60%
5 1l relative humidity), the drier systems of this invention (Examples
6 1~ 1 and 2) were almost as effective as the lead-containing drier
7 ¦ system (Comparative Example A), whereas the paint containing the
8 1 cobalt/zirconium/calcium drier system (Comparative Example B)
9 ~ gave an unsatisfactory performance in that it had not air dried
o ~ lin 24 hours under these conditions,as is required by the indu try.
12
13
14
1~ I
17
2:
21
2Z
23
24
26
27 ~
28
29
30 ~
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