JPS5936167A - Antifouling coating - Google Patents

Abstract

PURPOSE:To obtain titled coating with moderate water solubility, retaining its performance for long periods capable of giving tough coating film, for use in ships, bridges, underwater structures such as marine tanks, etc., by using as a vehicle, a water-insoluble resin and specific water-soluble one. CONSTITUTION:The objective coating can be obtained by using as a vehicle, a blend prepared by incorporating (A) 1-99wt% of a water-insoluble resin with (B) 99-1wt% of a water-soluble resin with its main chain constituted by a recurring unit of formula (n is 1-5; R1 and R2 are each H, 1-5C alkyl, halogen, phenyl, nitrile) (e.g., a residue of glycolic acid, lactic acid, beta-oxypropionic acid, gamma-oxypropionic acid, gamma-oxybutyric acid, epsilon-oxycapronic acid). EFFECT:Capable of simpler preparation at lower cost than the case of the coating of conventional dissolved matrix type; furthermore, capable of regulating the solubility of the entire coating film through the change in the weight ratio of the component (A) to (B). USE:For culture nets, stationary nets, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an antifouling paint using a synthetic resin composition having a tough coating film and appropriate water solubility as a vehicle.

Undersea structures such as ships, bridges, offshore tanks, and underwater parts such as aquaculture nets contain Fujibbo, Serpura, oysters,
A large number of marine organisms such as sea squirts, sea breams, sea lettuce, and green laver adhere to the structure, causing corrosion of structures and reductions in ship navigation speed.
Since large numbers of fish die due to poor drainage due to mesh clogging, there is a need for antifouling paints that have long-term antifouling properties.

Antifouling paint has approximately 2Rs from the mechanism that exerts its antifouling effect.
It is classified into One is the one that has been mainly used in the past, in which an antifouling agent is dispersed in a vehicle consisting of a seawater-insoluble resin such as vinyl chloride, chlorinated rubber, or styrene-butadiene, and a seawater-soluble component such as rosin. This is called an insoluble matrix type antifouling paint.

When this antifouling coating film f, fN is immersed in water, the antifouling agent is eluted together with the rosin and exhibits an antifouling effect, but even after the rosin has eluted, the insoluble resin residue layer remains. However, as the soaking process progresses, it becomes difficult for the antifouling agent to dissolve through this insoluble resin residue layer, and the antifouling period is only 12 to 16 months, requiring repeated recoating.

The other type was developed with the aim of eliminating the drawbacks of the above-mentioned insoluble matrix type antifouling paints.The resin itself is slightly water-soluble, and the vehicle of the paint film gradually dissolves in seawater. At the same time, the antifouling agent is eluted, and it is called a dissolved matrix type antifouling paint. In this case, since there is no insoluble resin residue layer that would be an obstacle to the elution of the antifouling agent, the antifouling agent can be easily eluted, and the antifouling performance is maintained as long as there is an antifouling coating, and the film thickness can be increased. By doing so, it is easy to maintain stain resistance for 2 to 3 years. As an antifouling paint invented with this intention in mind, 4? Publication No. 40-21426, Special Publication No. 44
-9579, Special Publication Showa 51-1204'? There is an antifouling paint. These inventions are (R)38r1-0-C-C
An organotin compound homopolymer represented by =CH-R' or a copolymer with other unsaturated compounds is used as a vehicle, and the above organotin ester group is hydrolyzed and released in seawater. The tin compound acts as an antifouling agent, and the resin itself is soluble in seawater, making it a soluble matrix type antifouling paint. [7]However, this organotin compound polymer has difficulty in synthesizing an organotin compound monomer having an unsaturated group, has poor storage stability, tends to increase in viscosity, is highly toxic, and is inconvenient to handle. There were practical difficulties such as the fact that

Therefore, as a result of intensive research, the present inventors have found a method for obtaining a soluble matrix type resin without using the above-mentioned organic tin compound polymer, using a resin normally used as the above-mentioned insoluble matrix type antifouling paint and a general paint. The inventors have discovered that a mixed resin obtained by mixing a specific resin that is decomposed by water with a specific resin that is decomposed by water is excellent as a vehicle for a soluble matrix type antifouling paint, leading to the present invention.

That is, the present invention provides a mixed resin gold vehicle consisting of 1 to 99% by weight of a water-insoluble resin and 99 to 1% by weight of a water-soluble resin having a υ barb unit in its main chain represented by the following general formula. The present invention provides an antifouling paint characterized by the following.

Examples of repeating units represented by the general formula (11) used in the present invention include glycolic acid residue, d], noractic acid residue, α-oxyisobutyric acid residue, α-oxy-n-
These include butyric acid residues, β-oxypropionic acid residues, α-chloropropionic acid residues, α-cyanopropionic acid residues, β-oxypivalic acid residues, and cuoxycaproic acid residues. A commonly used method is to use a corresponding cyclic lactone of an oxyacid as a monomer, and ring-opening polymerize one or more of them using a Lewis acid or a metal catalyst.

Examples of the cyclic lactone include glycolide, lactide, β-propiolactone, bivalolactone, γ-butyrolactone, δ-valerolactone, dacabrolactone, and the like.

A method for ring-opening polymerization of these cyclic lactones is described, for example, in US Pat. No. 2,668,162 (1954).

In the case of glycolide and lactide, a method of polymerizing three times is described. As an example of ring-opening polymerization of t-caprolactone, JP-A-56-49728 describes a method using a molybdenum compound as a catalyst.

However, the method for synthesizing the polymer is not limited to the opening III polymerization of cyclic lactones, but may also be a dehydration polycondensation method of oxyacids.

In the present invention, there is no particular restriction on the molecular weight of the resin obtained as described above, but from the viewpoint of maintaining strength as a coating film and improving coating workability, the weight average molecular weight is 1000.
+-100,000, particularly preferably 5000-50.
OOO is appropriate.

The water-soluble resin used in the present invention is a self-networking polyester of oxycarboxylic acid, and is structurally different from ordinary polyesters obtained from polybasic acids and polyhydric alcohols. Polyester is generally considered to have poor hydrolysis resistance, but ordinary polyester has a slow hydrolysis rate and cannot be used as a dissolution matrix type vehicle.

On the other hand, the self-condensation polyester of oxy .

Most of #1 can be used. Examples of the former include conventionally known oil-based varnishes, vinyl chloride,
Examples of the latter include various acrylic or methacrylic acid esters, mono- or copolymers of monoethylenically unsaturated compounds such as styrene, vinyl acetate, ethylene, propylene, etc. These include polyester, polyurethane, alkyd resin, melamine resin, urea resin, ketone resin, epoxy resin, polyether, petroleum resin, and modified derivatives thereof. There are no particular limitations on the molecular weight, monomer composition, modification method, etc. of these resins, but they must have a molecular weight that does not substantially have functional groups such as carboxyl groups or hydroxyl groups, and that maintains the strength of the coating film. It is necessary that there be.

The resin used as a vehicle in the present invention includes 1 to 99% by weight of the above-mentioned water-insoluble resin and 99 to 1% by weight of the water-soluble resin.
A mixed resin containing 5% by weight or more of a water-soluble resin is particularly preferred. If the amount of water uJ soluble resin is less than 1% by weight, the desired dissolution matrix type vehicle cannot be obtained, and if this amount exceeds 99% by weight, the effect will not change.

The mixed resin obtained by the present invention can be used as a soluble matrix because water-soluble resins are hydrolyzed by seawater and oligomerized by cutting the main chain. ) In the case of a resin having a repeating unit in the main chain, even an oligomer with a 1M degree of 20 or more has high water solubility, and as a result, the entire mixed resin is considered to become a soluble matrix. This is because it lacks the ability to accompany and elute conventional rosin-added resins.

The antifouling paint of the present invention can be prepared as described above by using the obtained mixed resin as a vehicle, coloring pigment, extender pigment, antifouling agent,
It is made into a paint by dispersing a solvent, etc.

The antifouling agents used in the antifouling paint of the present invention include cuprous oxide, tributyltin compounds, triphenyltin compounds,
All conventionally known antifouling agents including thiuram compounds can be used. Conventionally known pigments, additives, etc. can be used.

Moreover, any known method may be used to form the antifouling paint of the present invention into a paint.

The coating film obtained from the antifouling paint of the present invention has superior coating strength to conventional coatings using low-molecular compounds such as rosin, and also maintains a suitable elution rate of the antifouling agent stably for a long period of time. Because of this, for example, a coating with a dry coating thickness of 150 microns retains excellent antifouling performance even after 36 months.

In the present invention, a soluble matrix type can be obtained by simply mixing the above water-soluble resin with a water-insoluble resin, so the overall price can be reduced compared to the conventional one by using a large amount of inexpensive general resin. Furthermore, the solubility of the entire coating film can be changed as desired simply by changing the mixing ratio, and it also has major advantages such as being much easier to manufacture than conventional dissolution matrix types. .

Next, a detailed explanation will be given using manufacturing examples and examples.

In the examples, parts are parts by weight, viscosity is a value measured at 25°C, and molecular weight is a weight average molecular weight determined by GPC method.

Production Example 1 In a flask equipped with a stirrer, 464 parts of glycolide, 230.4 parts of L-lactide, sbp, 10. The os part was charged and heated at 195° C. for 2 hours under a nitrogen stream. 23 in next A
After raising the temperature to 0° C. and heating at that temperature for 1 hour, the heating was stopped and the contents of the flask were cooled by placing them in an oven batt, and the solidified material was crushed. The melting point of the obtained polymer is 207~
The temperature was 215°C and the molecular weight was 15,000. This resin 1 (
B-1 and vza, ooo) This is referred to as resin solution W-1.

Production Example 2 #12 of Resin B-1 obtained in Production Example 1. Of and 100JF of chlorinated rubber (manufactured by Kadenka Kogyo, CR-5) in xylene 11
21 to obtain a transparent liquid having a viscosity of 35 voices at 25°C. This is referred to as resin solution W-2.

Production Example 3 288 parts of L-lactide in a flask with a stirrer, s b
F (Io, o se part) was charged and heated in the same manner as in Production Example 1 under a nitrogen stream to obtain a colorless and transparent glassy solid.The resulting polymer had a pour point of 150'C and a molecular weight of 1.
It was 9,000. This resin is designated as B-2. [3-2
4.5 f and 10 oz of the vinyl chloride-vinyl acetate copolymer resin used in Production Example 1 were heated and dissolved using 104.5 f of a mixed solution of xylene-MIB, and 25
A clear liquid was obtained with a viscosity of 52 voices at °C. This is referred to as resin solution W-3.

Production Example 4 16. of Resin B-2 obtained in Production Example 3. Of, vinyl acetate, and 16.0 # of xylene were heated and mixed and dissolved to obtain a transparent liquid having a viscosity of 7.0 poise at 25°C. This is referred to as resin solution W-4.

Production Example 5 13. of Resin B-2 obtained in Production Example 3. Of and styrene-butadiene resin (manufactured by Gutdeyer, Briolide 85B)
) 100~, xylene 10tf: melt by heating,
A transparent liquid was obtained with a viscosity of 4.5 voices at 25°C.

This is referred to as resin solution W-5.

Production Example 6 50 parts of xylene was placed in a flask equipped with a stirrer and heated to reflux, followed by 10 parts of 2-ethylhexyl acrylate, 25 parts of methyl methacrylate, 10 parts of styrene, 5 parts of butyl acrylate, and 1-butyl-peroxybenzoate. 085 parts of the mixed solution was added dropwise over 1 hour, and heated under reflux for an additional 3 hours. 20O of resin solution A-1
8.6.9 of rsWA fat B-2 obtained in Production Example 3 and 8.61 of xylene were heated and mixed to obtain a transparent liquid having a viscosity of 60 poise at 1-125°C. Add this to the resin solution W-
Set it to 6.

Production Example 7 Plaxel H-1 (number average molecular weight to, o o o
) 301 and xylene sof were heated and mixed to obtain a transparent liquid having a viscosity of 6.5 poise at 25°C. This is referred to as 494 fat solution W-7.

Production Example 8 ε 251 of poly(/-caprolactone) used in Production Example 7
! - and epoxy resin (Epicoat I 007 manufactured by Yuka Shell Epoxy Co., Ltd.) 10011, X-ethyl cellosolve 100IF, and acetic acid ethylene glycol monoethyl ether 259 are heated and mixed to form a transparent liquid with a viscosity of 17.0 voices at 25"C. This is referred to as a resin solution ws.

Example Painting Using all of the resin solutions W-1 to W-S obtained in Production Examples 1 to B,
Example 1
This company manufactures antifouling paints from ~9.

Other examples of typical commercially available dissolved matrix type antifouling paints include Comparative Example 1 and Fui? Comparative Example 2 was manufactured as an example of the ¥ solution matrix type.

Example of Preparation of Painted Test Plate Antifouling Coatings of ~9 and Comparative Example 1.2 All sandblasted steel plates were coated with anticorrosive paint in advance, and the coated plates were coated twice with a brush to a dry film thickness of 150μ. An antifouling performance test board was created. Similarly, a certain IQ
A test plate for measuring the elution rate of the antifouling agent was prepared by applying the antifouling paint to only an area of am x 20 eg. Similarly, 4(
11cm x 15 with antifouling paint applied to an area of ) x 2α
A rotary drum for measuring the wear film thickness was prepared by wrapping a 7es+ aluminum plate around a circular drum.

Immersion test In Yura Bay, Sumoto City, Hyogo Prefecture, the antifouling performance test plate and elution rate tunnel 1 constant test plate were immersed in the sea for 36 months, and the rotary drum for measuring the wear film thickness was rotated in the sea for 2 months. I did it.

Immersion test results The results of the antifouling performance test by the immersion test are shown in Table 2, the results of the copper elution rate 4I are shown in Table 3, the results of the tin elution rate measurement are shown in Table 4, and the results of the wear film thickness d9j are shown in Table 4. It is shown in Table 5.

In general, the minimum antifouling limit concentration of each individual antifouling agent in seawater is considered to be 1 oγ/crI/day as copper for copper compounds, and lγ/cl 7 days as tin for tin compounds.

Table 2: Antifouling performance test results (expressed as % of attached area of attached organisms) Table 3: Copper elution rate 11 constant results (expressed as r/era 7 days) Note: The blank mark indicates that measurements cannot be made due to biofouling, etc. Displays as 0.

Table 4 Measurement results of tin elution rate (expressed in γ/d/day) Note: The next mark is displayed as 0 because illumination is unstable due to biofouling.

Table 5 Measurement results of worn film thickness (expressed in Bv thickness μm) Regarding the antifouling performance test in Table 2, all of the Examples and Comparative Example 1 showed 0% biological adhesion even after 36 months. However, in Comparative Example 2, significant biological adhesion was observed after 12 months. Regarding the elution rate tests for copper and tin in Tables 3 and 4, the Example shows that, like Comparative Example 1, the elution rate is higher than the minimum antifouling limit even after 36 months.

In addition, in Table 5, in the measured film thickness attrition, it can be seen that in all of the Examples, the film thickness gradually decreases as in Comparative Example 1 using an organic tin polymer, but in Comparative Example 2, the film thickness decreases gradually. There is no visible loss of thickness.

Physical performance test of paint film Examples 1 to 9 and Comparative Example 1, using the °2 antifouling paint,
Concerning the impact resistance and bending resistance of coating films, JIS-
5400, 6.13 and JIS-ni-54 (10.6
．． The test was conducted according to 15 methods. As a result, all of the Examples and Comparative Example 1 passed both the impact resistance and bending resistance tests, while Comparative Example 2 failed only the impact resistance test, and the bending resistance test passed in Comparative Example 2. passed it.

From the above, it is clear that the antifouling paint of the present invention using Rf) F4 fat as a vehicle exhibits excellent antifouling ability over a long period of time as a dissolved matrix type antifouling paint.

Comparative Example 1 has good antifouling performance, but as mentioned above, since it uses an organic tin compound polymer, its synthesis is difficult, its storage stability is poor, and its toxicity is too strong. There are many difficulties.

patent applicant

Claims (1)

[Scope of Claims] 1) A mixed resin consisting of 1 to 99% by weight of a water-insoluble resin and 99 to 1% by weight of a water-soluble resin having a backbone unit in the main chain expressed by the following general formula. An antifouling paint characterized by containing it as a vehicle. 2) General formula (1) is n = 1, n ] = H
The antifouling paint according to claim 1, which is a glycolic acid residue represented by , 112=H. 3) General formula (11 is n=1.R1=t(, R2=CH
3. The antifouling paint according to claim 1, which is a lactic acid residue represented by No. 3. 4) General formula (1) is n = 2, R1=H1R2=H
The antifouling paint according to claim 1, which is a β-oxypropionic acid residue represented by: 5) The antifouling paint according to claim 1, wherein the general formula is an r-oxybutyric acid residue represented by n=3, R1=H, R2=H. 6) General formula (1) is n = 5, R1 = H, R2 = H
The antifouling paint according to claim 1, which is an l-oxycaproic acid residue represented by ε.