Antifouling paint compositions

An antifouling paint containing a copolymer including a recurring unit of the formula: ##STR1## wherein R.sup.1 is hydrogen atom, methyl or an alkoxycarbonyl, R.sup.2 is hydrogen atom or an alkoxycarbonyl, A is an acid ion-terminated pendant group, M is a transitional metal ion, L is a monobasic organic acid ion, and m is the valency of the transitional metal M; and an amount of an organic ligand capable of coordinating to the transitional metal. The ion-association and reactivity of the metal in the copolymer may be retarded by complexing with the organic ligand in situ.

BACKGROUND OF THE INVENTION 
This invention relates to a novel antifouling paint composition. 
Antifouling paints containing as a vehicle resin a trialkyltin 
group-containing polymer are known as "self-polishing antifouling paints". 
When these paints are applied onto ships as a coating film, the film is 
gradually hydrolyzed by the action of weakly alkaline sea water to release 
the trialkyltin moiety at a constant rate for a long period of time, and 
at the same time the remaining film may be rendered water-soluble to 
expose a fresh surface of the tin-containing polymer. This smoothens the 
film surface consistently, decreases the frictional resistance of the 
ships and, therefore, economizes fuel consumption. 
The tin-containing polymers used in the known self-polishing antifouling 
paints consist typically of copolymers of trialkyltin acrylate or 
methacrylate with other ethylenically unsaturated monomers. 
However, ecological concern of massive release of organotin compounds into 
sea water makes the tin-based antifouling paints undesirable and a need 
arises for a new vehicle resin usable in the self-polishing antifouling 
paints. 
In Japanese Patent Kokai No. 16809/1989 published on Jan. 20, 1989 and 
assigned to the assignee of the present application, a metal-containing 
polymer is disclosed comprising a multivalent, metal salt of acrylic or 
methacrylic acid copolymers with a monobasic organic acid bound to the 
same metal ion to which the acrylate or mathacrylate anion is bound. 
It has been found, however, that this type of metal-containing polymers are 
liable to ion-association and tend to react with antifouling agents such 
as cuprous oxide or copper rhodanide or metal oxide pigments such as zinc 
oxide when formulated them together in an antifouling paint. Consequently, 
the paint formulations will become gelled or too viscous upon storage 
making them commercially impractical. 
Accordingly, it is a major object of this invention to provide a 
self-polishing antifouling paint of the above type which is free from 
these problems and is compatible with conventional antifouling agents or 
conventional metal oxide pigments. 
SUMMARY OF THE INVENTION 
The above and other objects are accomplished by the present invention by 
providing an antifouling paint composition comprising: 
(a) a copolymer consisting essentially of 5 to 80% weight of a first 
recurring unit of the formula: 
##STR2## 
wherein R.sup.1 is hydrogen atom, methyl or an alkoxycarbonyl, R.sup.2 is 
methyl or an alkoxycarbonyl, A is an acid ion-terminated pendant group, M 
is a transitional metal ion, L is a monobasic organic acid ion, and m is 
the valency of the transitional metal M; and the balance of the copolymer 
of a second recurring unit free from an acid function, said copolymer 
having a number average molecular weight from 2,000 to 100,000; and 
(b) an amount of an organic ligand at least equal to the ligand-to-metal 
coordination ratio of 1:1, said organic ligand being selected from the 
group consisting of aromatic nitro compounds, nitriles, urea compounds, 
alcohols, phenols, aldehydes, ketones, carboxylic acids and organic sulfur 
compounds. 
The above copolymer (a) may be considered as a hybrid salt. 
By coordinating an organic ligand to each metal atom, the ion-association 
of the hybrid salt is retarded significantly to have a lower viscosity in 
a solution compared with the corresponding solution not containing the 
organic ligand. Furthermore, improvements may be found both in the 
sustained release of metal ions and the film consumption rate. Another 
important advantage is the fact that the complexed hybrid salt is no 
longer reactive with conventional antifouling agents and pigments such as 
cuprous oxide, zinc oxide and the like. Therefore, the antifouling paint 
composition of the present invention is compatible with the conventional 
antifouling agents and pigments.

DETAILED DISCUSSION 
The polymeric hybrid salt containing the recurring unit of the formula 
##STR3## 
wherein all symbols are as defined, may be preferably produced by 
copolymerizing a corresponding acidic monomer and a corresponding neutral 
monomer, and then reacting the resulting polymeric acid with a compound of 
transitional metal and a monobasic organic acid. 
Typical examples of carboxylic acid monomers are acrylic acid and 
methacrylic acid, which are hereinafter collectively referred to as 
"(meth)acrylic acid". Other examples of carboxyl group-containing monomers 
include monoalkyl maleate and monoalkyl itaconate as well as half esters 
of a dicarboxylic acid such as phthalic, succinic or maleic acid with a 
hydroxyl group-containing monomer such as 2-hydroxylethyl (meth)acrylate. 
Examples of sulfonic group-containing monomers include p-styrenesulfonic 
acid, 2-methyl-2-acrylamidopropanesulfonic acid and the like. 
Examples of phosphoric group-containing monomers include acid 
phosphoxyethyl methacrylate, acid phosphoxypropyl methacrylate, 2-acid 
phosphosphoxy-3-chloropropyl methacrylate and the like. 
Examples of neutral monomers include hydrocarbon monomers such as ethylene, 
propylene, styrene, .alpha.-methylstyrene, vinyltoluene and 
t-butylstyrene; alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl 
(meth)acrylate, n-butyl (meth)acrylate and 2-ethylhexyl (meth)acrylate; 
hydroxyalkyl (meth)acrylate such as 2-hydroxyethyl (meth)acrylate, 
2-hydroxypropyl (meth)acrylate and hydroxybutyl (meth)acrylate; other 
monomers such as (meth)acrylamide, (meth)acrylonitrile, vinyl acetate, 
vinyl propionate, vinyl chloride and the like. 
By solution copolymerizing the acidic monomers and the neutral monomers, 
copolymers having a plurality of acid-terminated pendant groups may be 
produced. 
Transitional metals, namely elements of groups 3A to 7A, 8 and 1B, may be 
used for forming a salt with the polymeric acid. Co, Ni, Cu, Zn or Mn is 
preferable among others. 
The polymer hybrid salts may be produced by reacting the acid-terminated 
pendant group-containing polymer or an alkali metal salt thereof with an 
organic monobasic acid corresponding to the ligand L and an oxide, 
hydroxide, chloride, sulfide or basic carbonate of the transitional metal. 
Alternatively, the acid-terminated pendant group-containing polymer may be 
reacted with the organic monobasic acid salt of a transitional metal. It 
is also possible to copolymerize a corresponding monomeric hybrid salt 
with a neutral monomer. 
Examples of monobasic organic acids usable for forming the hybrid salt 
include monocarboxylic acids such as acetic, propionic, butyric, lauric, 
stearic, linolic, olei, naphthenic, chloroacetic fluoroacetic, abietic, 
phenoxyacetic, valeric, dichlorophenoxyacetic, benzoic or napthoic acid; 
and monosulfonic acids such as benzenesulfonic, p-toluenesulfonic, 
dodecylbenzenesulfonic, naphthalenesulfonic or p-phenylbenzenesulforic 
acid. 
A preferred method for producing the polymeric hybrid salt has been 
disclosed in Japanese Patent Kokai No. 16809/1989 cited hereinbefore. 
According to this method, copolymers containing pendant acid groups are 
reacted with a metal salt of low boiling point-monobasic organic acid and 
a high boiling point-monobasic organic acid simultaneously to form a 
hydbrid salt in which both the polymer pendant acid anion and the high 
boiling point-monobasic acid anion are bound to the same transitional 
metal cation. For example, a hybrid copper salt with the polymeric acid 
and naphthenic acid may be obtained by reacting the polymeric acid with 
cupric acetate and naphthenic acid. 
The polymer hybrid salts thus produced take a pseudo-crosslinked form due 
to ion-association and, therefore, have a relatively high viscosity in 
solutions. However, the viscosity may be decreased significantly by 
coordinating a further ligand to the hybrid salt in accordance with the 
present invention. The resulting polymer complex thus formed also exhibits 
a relatively constant rate both in metal release and film consumption when 
applied as an antifouling coating film. 
Organic ligands used for this purpose are selected from the group 
consisting of aromatic nitro compounds, urea compounds, nitriles, 
alcohols, phenols, aldehydes, ketones, carboxylic acids, and organic 
sulfur compounds. 
The organic ligands usable in the present invention are not limited to 
unidentate ligands but include polydentate ligand containing a plurality 
of same or different ligating atoms in the molecule. 
Specific examples of such ligands include aromatic nitro, compounds such as 
nitrobenzene; nitriles such as isophthalonitrile; urea compounds such as 
urea, thiourea, N-(3,4-dichlophenyl)-N'-methoxy-N'-methylurea or 
N-(3,4-dichlorophenyl)-N', N'-dimethylurea; alcohols such as butanol, 
octanol or geraniol; phenols such as hydroquinone, hydroquinone monomethyl 
ether, nonylphenol or BHT; aldehydes such as acetaldehyde or 
propionaldehyde; ketones such as acetylacetone, acetophenone or 
2-amino-3-chloro-1,4-naphthoquine; carboxylic acids such as acetic, 
propionic, benzoic, lactic, malic, citric or tartaric acid or glycine; and 
sulfur compounds such as thiophene and its derivatives, n-propyl 
p-toluenesulfonate, mercaptobenzothiazole, dimethyldithiocarbamate or 
benzeneisothiocyanate. Some of these ligands are used for antifouling 
purposes in the conventional antifouling paint formulations. 
The amount of organic ligand for complexing the polymer hybrid salt should 
be equal to or in excess of the ligand-to-metal coordination ratio of 1:1. 
The maximum will be such an amount to saturate the coordination number of 
a particular metal used. For example, when a metal specis having a 
coordination number of 4 is used, one or two moles of unidentate ligands 
or one mole of bidentate ligand may be coordinated to the metal atom. 
The organic ligands are incorparated to a solution or varnish of the 
polymer hybrid salt to form a polymer complex in situ. The presence of 
excessive amounts of the organic ligands may be tolerated unless coating 
films are adversely affected such as occurrence of cracks or blisters when 
soaked in saline. 
The complexed copolymer used in the antifouling paint of this invention 
consists essentially of 5 to 80%, preferably from 20 to 70% by weight of 
the copolymer of the first recurring unit (a), and the balance of the 
copolymer of the second recurring unit. If the proportion of the first 
recurring unit is too high, then the resulting film will be consumed too 
rapidly. Conversely, if the proportion of the first recurring unit is too 
low, then the resulting films will not be self-polishing. 
The complexed copolymer used herein should have a number average molecular 
weight from 4,000 to 100,000. Within this range of molecular weight, the 
copolymer will have an optimal viscosity for film-forming and workability 
purposes. However, since the viscosity is relatively low, the complexed 
copolymer may be formulated into high solids paints. 
The complexed copolymer may have a metal content from 0.3 to 20%, 
preferably from 0.5 to 15% by weight. 
The antifouling paint composition of the present invention may contain, in 
addition to the complexed copolymer, any conventional antifouling agent 
such as cuprous oxide or copper rhodanide as well as any conventional 
pigment such as zinc oxide, titanium oxide or iron oxide. Since the 
complexed copolymer is no longer reative with these additives, the 
composition is stable upon storage for a long period of time. 
The invention is further illustrated by the following examples in which all 
percents and parts are by weight unless otherwise specified. 
PRODUCTION OF COPOLYMERS CONTAINING PENDANT ACID GROUPS 
Example 1 
To a four necked flask equipped with a stirrer, a reflux condenser and a 
dripping funnel were added 120 parts of xylene and 30 parts of n-butanol, 
and the content was heated to 110.degree.-120.degree. C. To this was added 
dropwise a mixture of 60 parts of hexyl acrylate, 25 parts of 2-ethylhexyl 
acrylate, 15 parts of acrylic acid and 2 parts of azobisisobutyronitrile 
over three hours. After the addition, the mixture was kept at the same 
temperature for additional two hours. The resulting varnish had a solid 
content of 39.8% and an acid number of 200 mg KOH/g of the solid. 
Example 2 
To the same flask as used in Example 1 were added 100 parts of xylene and 
20 parts of n-butanol, and the content was heated to 
100.degree.-110.degree. C. To this was added a mixture of 25.7 parts of 
acrylic acid, 57.8 parts of ethyl acrylate, and 3 parts of 
azobisisobutyronitrile over one hour. After the addition, the mixture was 
kept at the same temperature for additional two hours. The resulting 
varnish had a solid content of 39.6% and an acid number of 200 mg KOH/g of 
the solid. 
Example 3 
To the same flask as used in Example 1 were added 100 parts of xylene and 
20 parts of n-butanol, and the content was heated to 
100.degree.-110.degree. C. To this was added a mixture of 7.7 parts of 
methacrylic acid, 64.4 parts of methyl methacrylate, 28 parts of 
2-ethylhexyl acrylate and 3 parts azobisisobutyronitrile over 4 hours. 
After the addition, the mixture was kept at the same temperature for 
additional two hours. The resulting varnish had a solid content of 39.8% 
and an acid number of 50 mg KOH/g of the solid. 
Example 4 
To the same flask as used in Example 1 were added 100 parts of xylene and 
20 parts of n-butanol, and the content was heated to 
100.degree.-110.degree. C. To this was added a mixture of 38.5 parts of 
acrylic acid, 50.9 parts of ethyl acrylate, 10.6 parts of n-butyl acrylate 
and 3 parts of azobisisobutyronitrile over four hours. After the addition, 
the mixture was kept at the same temperature for additional 30 minutes. 
The resulting varnish had a solid content of 39.4% and an acid number of 
300 mg KOH/g of the solid. 
PRODUCTION OF POLYMER HYBRID SALTS 
Example 5 
A four necked flask equipped with a stirrer, a reflux condenser and a 
decanter was charged with 100 parts of the varnish of Example 1, 20 parts 
of naphthenic acid and 7 parts of copper (II) hydroxide. The mixture was 
heated at 120.degree. C. for two hours while distilling off water produced 
as a by-product. A green varnish hereinafter referred to as "Varnish A" 
having a solid content of 51.3% and a viscosity of 2.2 poise was obtained. 
An aliquot of the varnish was treated with white spirit to precipitate the 
resin and analyzed for its copper content by fluorescent X-ray analysis. 
The copper content was 6.8%. 
Example 6 
The same flask as used in Example 5 was charged with 100 parts of the 
varnish of Example 2, 25.9 parts of zinc (II) acetate, 40.3 parts of oleic 
acid and 120 parts of xylene. The mixture was heated at 120.degree. C. 
while removing acetic acid by azeotropic distillation with xylene. The 
reaction was continued until no acetic acid was detected in the 
distillate. Varnish B thus produced had a solid content of 55.3% and a 
viscosity of R-S. 
Example 7 
The same flask as used in Example 5 was charged with 100 parts of the 
varnish of Example 3, 7.4 parts of copper (II) propionate, 10 parts of 
naphthenic acid and 10 parts of deionized water. The mixture was heated at 
100.degree. C. while distilling off water and propionic acid. The reaction 
was continued until no distillate was collected. Varnish C thus produced 
had a solid content of 52.3% and a viscosity of P. 
Example 8 
The same flask as used in Example 5 was charged with 100 parts of the 
varnish of Example 3, 8.1 parts of manganese (II) acetate and 7.8 parts of 
2,4-dichlorophenoxyacetic acid. The mixture was heated at 70.degree. C. 
while distilling off acetic acid. The reaction was continued until no 
acetic acid was detected in the distillate. Varnish D thus produced was 
diluted with 95 parts of xylene to a solid content of 56.3% and a 
viscosity of U. 
Example 9 
The same flask as used in Example 5 was charged with 100 parts of the 
varnish of Example 4, 37.2 parts of cobalt (II) acetate, 32.1 parts of 
Versatic acid and 120 parts of xylene. The mixture was heated at 
120.degree. C. while removing acetic acid by azeotropic distillation with 
xylene. Varnish E thus produced had a solid content of 55.8% and a 
viscosity of N. 
POLYMER COMPLEX VARNISH 
Examples 10-20 and Comparative Example 1 
Varnish A to Varnish E produced in Example 5-9 were complexed by mixing 
with various ligands as shown Table 1 below. As a control, Varnish A was 
used in Comparative Example 1 without addition of any ligand. 
Ligands used in these examples are as follows: 
A: Hydroquine 
B: Nonylphenol 
C: N-(3,4-dichlophenyl)-N'-methoxy-N'-methylurea 
D: N-(3,4-dichlorophenyl)-N',N'-dimethylurea 
E: 3,3,4,4-Tetrachloro-tetrahydrothiophene-1,1-dioxide 
F: Geraniol 
G: 2,4-Dichlorophenoxyacetic acid 
H: 2-Amino-3-chloro-1,4-naphthoquinone 
I: Benzoic acid 
J: Acetaldhyde 
TABLE 1 
__________________________________________________________________________ 
Polymer Complex Varnish 
Example No. 
10 11 12 13 14 15 16 17 18 19 20 Com. 
__________________________________________________________________________ 
1 
Varnish 
A B C D E A A A A A A A 
(parts) 
98 98 94 96 94 96 92 95 95 95 97 100 
Ligand 
A B C D E F G I J A B K -- 
(parts) 
2 2 6 4 6 4 8 5 5 2 3 3 
Total 
100 100 100 100 100 100 100 100 100 100 100 100 
(parts) 
__________________________________________________________________________ 
Film consumption rate 
Polymer complex varnishes of Examples 10-20 and Comparative Example 1 were 
applied on a rotor disc to a dry film thickness of about 140 .mu.m, and 
the disc was continuously rotated at a constant circumferential speed of 
about 30 knot in see water at a temperature of 18.degree.-22.degree. C. 
for two months. The film consumption rate was evaluated in terms of the 
consumed film thickness calculated by subtracting the residual film 
thickness after 2 month rotation from the initial film thickness. The 
results obtained are shown in Table 2 below. 
TABLE 2 
______________________________________ 
Film Consumption 
Consumed 
Initial film 
Residual film 
film 
Example No. 
thickness, .mu.m 
thickness, .mu.m 
thickness, .mu.m 
______________________________________ 
10 140 60 80 
11 145 25 120 
12 130 30 100 
13 130 50 80 
14 140 80 60 
15 150 50 100 
16 145 45 100 
17 140 50 90 
18 135 55 80 
19 140 0 &gt;140 
20 150 50 100 
Com. Ex. 1 
150 90 60 
______________________________________ 
It is evident from Table 2 that the film consumption rate can be controlled 
by selecting a suitable ligand species. 
Effect of ligands on varnish viscosity 
The varnish of Example 5 was thickened in vacuo to an initial viscosity of 
10,000 centipoise. To the varnish was added octyl alcohol or acetic acid, 
at a ligand-to-metal coordination ratio of 1:1, 2:1 and 4:1, respectively. 
As a control, xylene was used. Viscosities measured in each test are shown 
in Table 3 below. 
It is evident from Table 3 that the varnish viscosity decreases drastically 
by the addition of a complexing ligand. This means that the present 
invention enables a high solids antifouling paint having a solid content 
greater than 50% to be formulated, whereas a 40% solids content is 
practically maximum for the corresponding paint not containing the 
complexing ligand. 
TABLE 3 
______________________________________ 
Effect of Ligand on Varnish Viscosity 
Ligand/metal ratio 
Ligand o 1:1 2:1 4:1 
______________________________________ 
Octyl alcohol 
10000 cp 1300 cp 700 cp 
200 cp 
Acetic acid 10000 cp 1100 cp 400 cp 
200 cp 
Xylene 10000 cp 8000 cp 6000 cp 
3500 cp 
______________________________________ 
Metal releasing rate 
Varnishes of Examples 10-20 and Comparative Example 1 were applied on a 
polyvinyl chloride plate (15.times.10.times.0.1 cm) to a dry film 
thickness of about 100 .mu.m. The plate was immersed in sea water and the 
amount of metal ions leached in the sea water was determined over six 
months period. The results obtained are shown in Table 4 below. 
It is evident from Table 4 that a relatively constant metal release is 
sustained over a long period of time by the paint of the present 
invention. 
TABLE 4 
__________________________________________________________________________ 
Metal Releasing Rate (.mu.g metal/cm.sup.2 film/day) 
Ex. No. Comp. 
Period 10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 
Ex. 1 
__________________________________________________________________________ 
0 8 7.5 
6.0 
6.5 
9.0 
6.0 
6.0 
7.5 
6.5 
9.0 
6.5 
10.0 
Week 0-2 4.0 
4.0 
3.5 
6.0 
4.0 
4.5 
4.5 
4.5 
6.0 
8.5 
6.0 
4.0 
Week 2-Month 1 
4.0 
4.5 
3.5 
4.0 
4.0 
4.5 
4.0 
5.0 
4.0 
7.5 
4.0 
3.0 
Month 1-2 3.5 
4.5 
4.0 
4.5 
4.5 
3.5 
4.0 
5.5 
4.0 
7.0 
4.5 
2.5 
Month 2-3 4.0 
4.0 
4.5 
4.0 
4.0 
3.0 
4.5 
5.0 
4.0 
6.0 
4.0 
2.0 
Month 3-4 4.0 
4.0 
4.0 
3.5 
4.5 
3.5 
4.0 
5.0 
3.5 
6.5 
3.5 
0.0 
Month 4-5 3.0 
4.0 
4.5 
3.5 
4.5 
4.5 
4.0 
5.5 
3.5 
7.0 
3.5 
0.0 
Month 5-6 4.0 
4.0 
3.5 
4.0 
4.5 
4.0 
4.0 
5.0 
4.0 
6.5 
4.0 
0.0 
__________________________________________________________________________ 
Paint formulations 
Using Varnish A of Example 5 to Varnish D of Example 8, various antifouling 
paints were formulated by the conventional method and tested for storage 
stability. 
______________________________________ 
Example 21 
Varnish A 50 parts 
Octanol 5 parts 
Cu.sub.2 O 30 parts 
Red iron oxide (Fe.sub.2 O.sub.3) 
5 parts 
Xylene 5 parts 
Methyl isobutyl keton (MIK) 
5 parts 
Total 100 parts 
Example 22 
Varnish B 50 parts 
Dodecyl alcohol 5 parts 
Cu.sub.2 O 30 parts 
TiO.sub.2 5 parts 
Xylene 5 parts 
MIK 5 parts 
Total 100 parts 
Example 23 
Varnish B 40 parts 
Isononanoic acid 8 parts 
Cu.sub.2 O 27 parts 
Fe.sub.2 O.sub.3 5 parts 
Xylene 10 parts 
MIK 10 parts 
Total 100 parts 
Example 24 
Varnish B 50 parts 
Ethylene glycol 12 parts 
Benzoic acid 3 parts 
Cu.sub.2 O 20 parts 
Fe.sub.2 O.sub.3 5 parts 
MIK 10 parts 
Total 100 parts 
Example 25 
Varnish A 40 parts 
Octanol 2 parts 
Acetic acid 1 parts 
Cu.sub.2 O 30 parts 
Fe.sub.2 O.sub.3 2 parts 
ZnO 10 parts 
Xylene 10 parts 
MIK 5 parts 
Total 100 parts 
Example 26 
Varnish A 45 parts 
Acetic acid 0.5 parts 
Cu.sub.2 O 5 parts 
Fe.sub.2 O.sub.3 5 parts 
ZnO 25 parts 
Xylene 9.5 parts 
MIK 10 parts 
Total 100 parts 
Example 27 
Varnish A 50 parts 
Nitrobenzene 3 parts 
Cu.sub.2 O 30 parts 
Fe.sub.2 O.sub.3 5 parts 
Xylene 7 parts 
MIK 5 parts 
Total 100 parts 
Example 28 
Varnish B 50 parts 
Isophthalonitrile 10 parts 
Cu.sub.2 O 25 parts 
TiO.sub.2 5 parts 
Xylene 5 parts 
MIK 5 parts 
Total 100 parts 
Example 29 
Varnish C 50 parts 
Hydroquinone 7 parts 
monomethyl ether 
Cu.sub.2 O 23 parts 
ZnO 10 parts 
MIK 10 parts 
Total 100 parts 
Example 30 
Varnish A 40 parts 
Octylphenol 12 parts 
TiO.sub.2 5 parts 
ZnO 23 parts 
Xylene 10 parts 
MIK 10 parts 
Total 100 parts 
Example 31 
Varnish B 40 parts 
Hydroquinone 2 parts 
CuSCN 23 parts 
TiO.sub.2 10 parts 
Xylene 15 parts 
MIK 10 parts 
Total 100 parts 
Example 32 
Varnish C 40 parts 
BHT 6 parts 
Cu.sub.2 O 5 parts 
ZnO 30 parts 
Xylene 10 parts 
MIK 9 parts 
Total 100 parts 
Example 33 
Varnish B 40 parts 
Nonylphenol 5 parts 
Cu.sub.2 O 25 parts 
Fe.sub.2 O.sub. 3 5 parts 
Xylene 15 parts 
MIK 10 parts 
Total 100 parts 
Example 34 
Varnish D 50 parts 
N,N-dimethyl-N'-phenylurea 
8 parts 
Cu.sub.2 O 10 parts 
ZnO 20 parts 
Xylene 2 parts 
MIK 10 parts 
Total 100 parts 
Example 35 
Varnish B 50 parts 
N-(3,4-dichlorophenyl)- 
12 parts 
N'-methoxy-N-methylurea 
Cu.sub.2 O 20 parts 
Fe.sub.2 O.sub.3 5 parts 
MIK 10 parts 
Total 100 parts 
Example 36 
Varnish A 40 parts 
N-(3,4-dichlorophenyl)- 
5 parts 
N',N'-dimethylurea 
Cu.sub.2 O 30 parts 
ZnO 10 parts 
Xylene 10 parts 
MIK 5 parts 
Total 100 parts 
Example 37 
Varnish A 45 parts 
3,3,4,4-Tetrachloro- 5 parts 
tetrahydrothiophene-1,1- 
dioxide 
Fe.sub.2 O.sub.3 15 parts 
ZnO 15 parts 
Xylene 10 parts 
MIK 10 parts 
Total 100 parts 
Example 38 
Varnish C 50 parts 
Hydroquinone 1 parts 
Nonylphenol 4 parts 
CuSCN 20 parts 
ZnO 10 parts 
Xylene 10 parts 
MIK 5 parts 
Total 100 parts 
Comparative Example 2 
Varnish A 50 parts 
Cu.sub.2 O 30 parts 
Fe.sub.2 O.sub.3 5 parts 
Xylene 10 parts 
MIK 5 parts 
Total 100 parts 
Comparative Example 3 
Varnish B 40 parts 
CuSCN 25 parts 
TiO.sub.2 10 parts 
Xylene 15 parts 
MIK 5 parts 
Total 100 parts 
Comparative Example 4 
Varnish A 45 parts 
Cu.sub.2 O 5 parts 
Fe.sub.2 O.sub.3 5 parts 
ZnO 25 parts 
Xylene 10 parts 
MIK 10 parts 
Total 100 parts 
Comparative Example 5 
Varnish C 50 parts 
CuSCN 20 parts 
ZnO 10 parts 
Xylene 15 parts 
MIK 5 parts 
Total 100 parts 
Comparative Example 6 
Varnish D 50 parts 
Cu.sub.2 O 10 parts 
ZnO 20 parts 
Xylene 8 parts 
MIK 10 parts 
Total 100 parts 
Comparative Example 7 
Varnish B 40 parts 
Cu.sub.2 O 25 parts 
Fe.sub.2 O.sub.3 5 parts 
Xylene 15 parts 
MIK 15 parts 
Total 100 parts 
______________________________________ 
Storage stability 
Antifouling paint formulations of Examples 21-38 and Comparative Examples 
2-7 were tested for stability during storage. 
A 250 ml aliquot of each paint was placed in a 300 ml glass container and 
sealed therein. Storage stability was evaluated in terms of varnish 
separation, precipitation and viscosity increase after storaging for one 
month at 50.degree. C. The results obtained are shown in Table 5 below. 
TABLE 5 
______________________________________ 
Storage Stability 
Example 
Varnish Viscosity 
Overall 
No. separation Precipitate 
increase judgement 
______________________________________ 
21 None None Substan- Very good 
tially no 
change 
22 " " Substan- " 
tially no 
change 
23 " " Substan- " 
tially no 
change 
24 " Soft ppt. Slight Good 
25 " None Substan- Very good 
tially no 
change 
26 " " Substan- " 
tially no 
change 
27 " " Substan- " 
tially no 
change 
28 " " Substan- " 
tially no 
change 
29 " " Substan- " 
tially no 
change 
30 " Soft ppt. Substan- Good 
tially no 
change 
31 " None Substan- Very good 
tially no 
change 
32 " " Substan- " 
tially no 
change 
33 " " Substan- " 
tially no 
change 
34 " " Substan- " 
tially no 
change 
35 " " Substan- " 
tially no 
change 
36 " " Substan- " 
tially no 
change 
37 " " Substan- " 
tially no 
change 
38 " " Substan- " 
tially no 
change 
Comp. 
Ex. 2 Yes Hard ppt. Remarkable 
Not good 
Ex. 3 None " " " 
Ex. 4 Yes " Gelling " 
Ex. 5 None " Remarkable 
" 
Ex. 6 Yes " " " 
Ex. 7 None " " " 
______________________________________