JPS583505B2 - Polyol-curing two-component urethane paint - Google Patents

Description

Detailed Description of the Invention The present invention provides a polyol-cured two-component urethane paint, and more specifically, contains silicon phosphate as a reaction inhibitor in the paint system to adjust pot life, prevent foaming, and stabilize storage. Regarding polyol-cured two-component urethane paints that can efficiently measure the Then, other additives, solvents, etc. are appropriately blended, and immediately before painting, the mixture is mixed with various incyanate compounds as hardening agents and used for painting.

Furthermore, polyol-cured two-component urethane paints that do not contain coal tar are used in a similar manner.

Such paints generally have excellent chemical resistance, adhesion, flexibility, water resistance, and solvent resistance (especially resistance to aliphatic hydrocarbon solvents), and they react easily at room temperature and remain stable, especially in winter. Because it has superior low-temperature curing properties compared to other room-temperature-curing two-component paints, it can be used for various storage tanks, ship-related outer panels, rudders and tanks, as well as other industrial equipment, marine equipment, water equipment, and agricultural equipment. It is mainly used for external anti-corrosion coating and lining of steel products, etc.

According to such urethane paints, reactions between various polyol resins and isocyanate compounds (/~~OH~N
A cured coating film can be obtained by using CO→~NHCOO~~~), but tar urethane paints in particular contain coal tar, making it difficult to control the above reaction, making it difficult to adjust the pot life, prevent foaming, and store. Subsequent pot life stabilization has been an important issue in the design of such coatings.

In other words, since Coal Cool itself has NH2 groups, NH groups, etc., these act as catalysts for the addition reaction of the OH groups and NCO groups, significantly shortening the pot life and also causing foaming, especially when storing such paints. C
There is also.

Under such circumstances, in order to suppress the catalytic action of the above components, inorganic or organic incyanate compounds, sulfuric acid, phosphoric acid, organic phosphate esters, etc. are added to the coal tar in advance to inactivate the catalyst components therein. After that, the paint was adjusted, and methyl formate was added to the paint to prevent foaming.

However, these reaction inhibitors are difficult to use due to the process, their inhibitory effects become unstable due to changes in the paint over time, and they also have a significant negative impact on coating performance. , it lacked practicality.

If the device is to be used while being aware of such problems, it is necessary to limit the period of use to low temperatures.

The present inventors conducted research to provide a paint that satisfies the various performances of the urethane paint described above and has stable workability, and as a result, they adopted silicon phosphate as a reaction inhibitor and applied it to the paint. It was discovered that by mixing the components (excluding the curing agent) all at once to form a paint, there was no need to pre-treat the coal tar, and a polyol-cured two-component tar urethane paint, which was the intended purpose, could be obtained. The present inventors have discovered that even urethane paints that do not contain coal tar are effective in suppressing and stabilizing pot life, and have completed the present invention.

That is, the gist of the present invention resides in a polyol-cured two-component urethane paint and a polyol-cured two-component tar urethane paint, which are characterized by containing silicon phosphate as a reaction inhibitor.

By conveniently using silicon phosphate as a reaction inhibitor in the paint of the present invention, a permanently stable pot life can be provided even when stored under various conditions ranging from low to high temperatures, and granules etc. can be prevented during paint storage. A high-performance coating film can be formed without any abnormalities occurring.

This is because the silicon phosphate particularly effectively suppresses the activation of the catalyst component in coal tar, and it is surprising that it has such a remarkable effect.

Silicon phosphate in the present invention has the general formula Si02.nP
In the formula 205C, n is 0.1 to 2], and it is particularly preferable that the water-soluble component is 0.05 to 5% by weight and the hydrogen ion concentration is 3 or less.

Such silicon phosphate is produced by, for example, intimately mixing amorphous silica and phosphorus oxyacid, and then adding 200 to 400% of the mixture.
Produced by roasting at ℃.

In the paint of the present invention, the amount of silicon phosphate used is not particularly limited and may be determined depending on the desired reaction suppression effect, for example, 3 to 23 parts by weight per 100 parts by weight of coal tar. parts, preferably in the range of 6 to 18 parts by weight.

If the amount used is less than 3 parts by weight, a sufficient reaction suppression effect will not be obtained and the pot life will be shortened during paint storage, while if it exceeds 24 parts by weight, the drying of the target paint will be tends to decrease significantly.

Further, in a paint system that does not contain coal tar, the amount of silicon phosphate used is normally selected within a range of 0.5 to 5 weight percent in the paint.

Conventionally known techniques may be employed for other components and their blending ratios in the paint of the present invention.

Ordinary coal tar may be used;
Common coal tar, which is a product of dry distillation of coal, such as cutback cool and refined tar, has a melting point of about 30 to 300.
A pinch of °C can also be used.

In case of a pinch, it is desirable to use it in a state dissolved in an appropriate solvent.

The resin vehicle may be a known synthetic resin used in ordinary polyol-cured two-component tar urethane paints or urethane paints, or other compounding agents.

Examples of polyol resins include polyester polyols, polyether polyols, acrylic polyols, castor oil derivatives, tall oil derivatives, and other hydrous acid group compounds.

Examples of the curing agent include diincyanates or polymers thereof such as tolylene diisocyanate and dipherylmethane diisocyanate, polyisocyanates or derivatives thereof, and other incyanate-containing compounds.

Other color pigments (Begara, Rikiichi Bomb Black, Titanium White,
aluminum powder, etc.), extender pigments (barite powder, asbestin, clay, talc, etc.), various additives (antisettling agents,
Leveling agents, etc.), solvents (xylol, methyl isobutyl ketone, etc.), etc. may be blended.

The paint of the present invention is produced by mixing all the ingredients except for the incyanate compound as a curing agent with the silicon phosphate, and dispersing it with a conventional dispersion device (e.g., ball mill, triple roll) to obtain a paint liquid. It is prepared either as it is or after adjusting the viscosity with a solvent and adding a curing agent, isone anate compound or its diluted solution immediately before painting.

When it comes to painting, it can be applied to various objects, especially steel objects, usually by airless spray painting, or in some cases by roller painting, brush painting, or other commonly used painting methods, and it can be applied to various objects, especially steel objects, to achieve the intended purpose. A stable pot life and anti-foaming effect within the coating film can be achieved.

The paint of the present invention having the above structure has excellent storage stability, and in particular maintains a stable pot life over time regardless of the temperature during storage, and can prevent foaming within the paint film, resulting in stable painting. It maintains workability and can exhibit the coating film performance inherent to tar urethane paints.

Therefore, it can be said to be extremely useful from the point of view of practicality and economy, as an anticorrosive coating for various types of steel objects, such as ships' tanks, industrial equipment, pipes for water supply equipment, and the like.

Next, the present invention will be specifically illustrated by giving Examples, Comparative Examples, and Reference Examples.

Note that "parts" and "%" in the example sentences mean "parts by weight" and "% by weight."

Example 1 Silicon phosphate (trade name “Collodinone SP-” manufactured by Mizusawa Chemical Co., Ltd.)
028'', Si02/P205 (molar ratio) = 2/1, water-soluble component o. s %, hydrogen ion concentration 1.5), 2 parts of coal tar (low viscosity cutback cool),
30 parts of talc, 15 parts of barite powder, polyol resin (trade name: "Epiclon H201-" manufactured by Dainippon Ink & Chemicals Co., Ltd.)
60BBT") 9.5 parts of epoxy resin (trade name "Epicote 1004" manufactured by Shell Chemical Co., Ltd.), 6.5 parts of hydrogenated castor oil-based thixotropic agent (trade name "Disparon 43" manufactured by Kusumoto Kasei Co., Ltd.)
00'') 0.8 parts, male isobutyl ketone (MIBK
) and 9 parts of xylene were placed in a ball mill and dispersed for about 16 hours to obtain a coating liquid.

To 90 parts of the above coating liquid, add 10 parts of urethane curing agent liquid (product name: "Coronate L55ET" manufactured by Nippon Polyurethane Industries Co., Ltd.)
A tar urethane paint is prepared by stirring and mixing the following parts.

The pot life of such paints is shown in Table 1.

In addition, in the pot life measurement test, when blending the above-mentioned coating liquid and curing agent liquid, the coating liquid was not stored but immediately stored or stored at 40 ° C for 14 days (B) before being subjected to compounding.
The obtained paint was subjected to viscosity measurement using a B-type viscometer (No. 4 rotor, rotation speed 6, rpm, 60 rpm)
The measurement time was 0 to 180 minutes).

Examples 2 to 3 and Comparative Example 1 According to the method of Example 1, a coating liquid with the following formulation (number of parts) was obtained (the types of components used were the same as in Example 1).
Next, 10 parts of the same urethane curing agent liquid was added to 90 parts of this coating liquid in the same manner as in Example 1 to prepare a tar urethane paint.

The pot life of such paints is shown in Table 1.

Next, a concrete graph of the pot life results when the viscosity was measured at a rotational speed of 6 Orpm in Table 1 is shown in FIG.

From the results of Table 1 (and Figure 1), Examples 1 to
According to the polyol-cured two-component tar urethane paint (d) according to the present invention in item 3, it is recognized that a stable pot life can be obtained under various storage conditions.

16 (It is clear that if the amount of silicon phosphate used is too small as in Example 2, the effect will be slightly inferior).

On the other hand, it is understood that in Comparative Example 1, which represents one aspect of the prior art, the pot life may be short or short, but it becomes significantly shorter over time under storage conditions.

Reference Examples 1 to 5 According to the method of Example 1, the component proportions (number of copies) shown in Table 2
A coating solution was obtained (the types of components used were the same as in Example 1), and then 54 parts of the same urethane curing agent solution as in Example 1 was blended with 100 parts of this coating solution to obtain a tar urethane coating. Prepare.

The pot life of such a paint is shown in Table 3. The pot life measurement test was conducted immediately (a) without storing the paint liquid or at 400 m
Storage at ℃ x 3 days (1), storage at 40℃ x 7 days (c)
Alternatively, it was stored at 40° C. for 14 days (d) and then used for formulation, and the resulting coating material was subjected to viscosity measurement in the same manner as in Example 1 (however, the number of rotations was 6 rpm).

From the results in Table 3, it can be seen that in Reference Examples 3 to 5, the viscosity increases slowly after mixing the curing agent liquid (i.e., the pot life in the case of coating becomes longer), and there is no economical change due to storage. It is recognized that

On the other hand, in Reference Example 1, there was a rapid increase in viscosity after mixing the curing agent liquid, and an even more rapid increase in viscosity over time due to the storage conditions, indicating that it was impossible to make it into a paint.

Furthermore, in Reference Example 2, due to the use of silicon phosphate, the viscosity increase was significantly slower than in Reference Example 1, but
Since the amount used is small, it is observed that the viscosity increases gradually over time under storage conditions.

Thus, it can be seen that in the paint of the present invention, the silicon phosphate effectively controls the activation of the catalyst component in the coal tar over time under storage conditions.

Reference Example 6 The tar urethane paints prepared in Examples 1 and 3 and the same type of thick film airless paintable tar urethane paint commercial product A
and B were respectively applied to a sandblasted steel plate at a dry film thickness of 200 μm, and these were applied at a temperature of 40°C or 6°C.
Immersed in 3% saline solution at 0°C (immersed at 40°C for 3 months, 60°C)
℃ immersion for 10 days), and the coating film performance after immersion was evaluated.

The results are shown in Table 4.

From Table 4, it is recognized that silicon phosphate, which is a reaction inhibitor for the tar urethane paint according to the present invention, does not have any adverse effect on the coating film performance.

Example 4 The same silicon phosphate as in Example 1 (“Collodinone SP-02
8"), 60 parts of barite powder, 9 parts of titanium oxide (trade name: F Titanium R-930, manufactured by Sakai Chemical Industries, Ltd.), and the same hydrogenated castor oil-based thixotropic agent as in Example 1 ("Disparon 43
00") 0.5 part, polyol resin ("Epicron H2
01-60BT''), 7 parts of MIBK, and 7 parts of Kijiroll were placed in a ball mill and dispersed for about 16 hours to obtain a coating liquid.

A urethane paint is prepared by stirring and mixing 10 parts of a urethane curing agent liquid (trade name: Coronate L75, manufactured by Nippon Polyurethane Industries, Ltd.) with 100 parts of the above paint liquid.

The pot life and drying time of such paints are shown in Table 5.

The pot life measurement test was conducted in the same manner as in Example 1 using a paint that was immediately formulated without storing the above paint liquid.

Example 5 and Comparative Example 2 According to the method of Example 4, a coating liquid with the following formulation (number of parts) was obtained (the types of components used were the same as in Example 4).
Next, 10 parts of the same urethane curing agent liquid as in Example 4 was added to 100 parts of this paint liquid to prepare a urethane paint.

The pot life and drying time of such paints are shown in Table 5.

Next, a concrete graph of the pot life results when the viscosity was measured at a rotation speed of 6 Orpm in Table 5 is shown in FIG.

From the results of Coating No. 5 (and Fig. 2), it was found that by adjusting the amount of silicon phosphate used, the pot life could be stabilized and It is recognized that the drying time of the paint can be freely controlled.

It is understood that if the amount used is too large as in Example 5, the effect of suppressing the reaction will be too large and will have an adverse effect on the drying properties of the paint.

[Brief explanation of drawings]

FIGS. 1 and 2 are graphs embodying the pot life results when the viscosity was measured at a rotation speed of 6 Orpm as shown in Tables 1 and 5, respectively.

Claims (1)

[Scope of Claims] 1. A polyol-curing two-component urethane paint characterized by containing silicon phosphate as a reaction inhibitor. 2. A polyol-curing two-component tar urethane paint characterized by containing silicon phosphate as a reaction inhibitor. 3. The paint according to item 2 above, wherein the amount of silicon phosphate used is 3 to 24 parts by weight based on 100 parts by weight of coal tar.