JPS60124660A - Rust-resisting pigment - Google Patents

Abstract

PURPOSE:To provide a rust-resisting pigment which is white and low in toxicity, does not cause environmental pollution and has improved rust-proofness, containing a specified zinc potassium phosphite phosphate compd. as an active ingredient. CONSTITUTION:The titled pigment contains, as an active ingredient, a zinc potassium phosphite phosphate compd. formed by reacting a zinc compd., a potassium compd., a phosphorous acid compd., a phosphoric acid compd. and an org. phosphonic acid (salt) together. Preferred examples of the org. phosphonic acids (salts) are aminoalkylenephosphonic acids of formula I (wherein R is lower alkyl; m is 0-3; n=1-2; Z is H, alkali metal, ammonium group), ethylenediaminetetraalkylenephosphonic acids of formula II (wherein n is 1-3) and alkylmethane-1-hydroxy-1,1-diphosphonic acids of formula III (wherein R is H, lower alkyl) an their salts. The org. phosphonic acid (salt) is used in a quantity of at least 2wt%.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an anticorrosive pigment containing an improved potassium phosphite zinc phosphate compound as an active ingredient.

Conventionally, "CtA" is the most representative anti-rust pigment.
J') or zinc chromates are widely used. These anti-rust pigments exhibit extremely excellent anti-rust properties, but their toxicity has recently become an issue because they contain toxic metals such as lead and chromium. Alternatively, there was a demand for the development of non-polluting rust-preventing pigments. In response to this demand, many proposals have been made as non-polluting rust-preventing pigments.

So far, non-polluting rust-preventive pigments have been used as (a) metal condensed phosphates, such as condensed aluminum phosphate, (b) metal phosphates, such as silicon phosphate, titanium phosphate, and (C) metal phosphites. (d) metal hypophosphite systems such as calcium hypophosphite or iron hypophosphite; and (e) metal molybdates such as zinc salts. Many proposals have been made, such as , calcium salts, etc., but these non-polluting rust preventive pigments are not as definitive as rust preventive pigments as their rust preventive properties are not as good as lead-based and chromate-based pigments. Currently, two or three types of pigments are used in combination in order to obtain the necessary rust prevention properties.

By the way, the present applicant has developed a white potassium zinc phosphite pigment that is non-polluting and has excellent rust prevention properties, unlike the conventional rust prevention pigments, and has already filed a patent application (Japanese Patent Application No. 80
No. 090).

The present invention was developed as a result of research to further improve the rust prevention properties of the pigments mentioned above, and the results were obtained using phosphorous acid and a portion of organic phosphonic acid (1!!
), it was discovered that the effect was remarkable and was completed.

That is, the present invention is characterized in that the active ingredient is a phosphite zinc potassium phosphate compound produced by reaction with a zinc compound, a potassium compound, a subtinous compound, a phosphoric acid compound, and an organic phosphonic acid (salt). This applies to antirust pigments.

In the rust preventive pigment according to the present invention, among the raw materials that can be used to produce the potassium phosphite zinc phosphate compound contained as an active ingredient, zinc compounds include, for example, zinc oxide, zinc hydroxide, zinc carbonate, basic Zinc oxide such as zinc carbonate, zinc phosphate, zinc hydrogen phosphate, activated zinc white, etc., or zinc compounds and potassium compounds that can produce it, include:
Potassium oxides such as potassium oxide, potassium hydroxide, potassium phosphate, potassium hydrogen phosphate, potassium carbonate, potassium hydrogen carbonate, potassium compounds that can produce potassium oxides, and phosphoric acid compounds include phosphoric acid, zinc phosphate, phosphoric acid Examples of phosphoric acids such as zinc hydrogen, potassium phosphate, and potassium hydrogen phosphate, or phosphoric acid compounds and phosphorous acid compounds that can generate them, include phosphorous acids such as phosphorous acid and potassium phosphite, or phosphorous acids that can generate them. Hydrous potassium phosphite compounds and the like are suitable.

In addition, as an organic phosphonic acid (salt), the general formula % formula % () [wherein R is a lower alkyl group, m is θ ~ 3, n = 1 ~ 2,
Z represents hydrogen, alkali metal or ammonium group]
Aminoalkylenephosphonic acid or its salt represented by
Ethylenediaminetetraalkylenephosphonic acid or its salt represented by the general formula % formula % () [wherein n is an integer of 1 to 3, Z is synonymous with bending], and the general formula [wherein R is a hydrogen atom] or a lower alkyl group, Z is 111
Synonymous with formula 1] Alkylmethane-1-hydroxy-1,1 represented by
- Diphosphonic acid or its salts are suitable.

Among the compounds represented by the general formulas (+)', ('n), and (m), examples of the compound of formula (1) include nitrilotrismethylenephosphonic acid, nitrilotrisethylenephosphonic acid, and nitrilotrispropylenephosphonic acid. , nitrilodiethylmethylenephosphonic acid, nitrilopropylbismethylenephosphonic acid, etc. Examples of compounds of formula (■) include ethylenediaminetetramethylenephosphonic acid, ethylenediaminetetraethylenephosphonic acid, ethylenediaminetetrapropylenephosphonic acid, (1) Examples of compounds of the formula include methane-1-hydroxy-1,1
-Diphosphonic acid, ethane-1-hydroxy-1,1-diphosphonic acid, propane-1-hydroxy-1,1-diphosphonic acid and salts thereof include a part or Examples include those that are completely neutralized, and one or more of them may be used.

The rust-preventing pigment according to the present invention has as an active ingredient a potassium phosphite zinc phosphate compound, which is a white insoluble substance produced by a wet mixing reaction using the five types of compounds listed above as raw materials. Various mixed reactions are adopted depending on the type of raw materials and the type of reaction equipment, so the desired method can be set appropriately. A method in which an aqueous solution (solution B) consisting of a phosphoric acid compound such as phosphoric acid, a phosphorous acid compound such as phosphorous acid, and an organic phosphonic acid (salt) is dropped into an aqueous potassium oxide solution (solution A), or a method in which solutions A and B are simultaneously added. A method of contact mixing, a method of adding phosphorous acid, phosphoric acid, an organic phosphonic acid (salt) and an aqueous potassium hydroxide solution separately and simultaneously or separately over time to an aqueous zinc oxide slurry, or a method of adding phosphorous acid, phosphoric acid and an organic phosphoric acid to an aqueous slurry of zinc oxide. Examples include a method in which potassium hydroxide is added to a phosphonic acid (salt) mixed aqueous solution to neutralize it, and this is mixed with a zinc compound, but the method is not necessarily limited to 1-. Further, this reaction can be carried out either in a bunch type or in a continuous type, and depending on the reaction apparatus, a uniform mixing reaction can be carried out by ordinary stirring mixing, mixing in a static mixer, shear mixing, or a combination thereof.

In the second reaction, the organic phosphonic acid (salt) is used as a substitute raw material for phosphorous acid, and is required to be used in an amount of at least 2% by weight based on the phosphorous acid. The reason for this is 2.
This is because when the weight percent is unvortexed, no improvement in rust prevention is observed due to its addition, and the upper limit of the amount added is not particularly limited, but is up to 30 weight percent, preferably up to 20 weight percent.

The mechanism of this reaction is not clear due to the complexity of the reaction system, but if we exclude the organic phosphonic acid (salt), in principle, the following reaction formula aK20 + bZnO+ cH2PH03+ dHa
PO4-+ (1-x)K2O・xZnO-y [(1
-z)H2PHOa・TzHaPO,]-nH,0...
・・・・・・・・・・・・(Ill) Since the organic phosphonic acid (salt) reacts and is not substantially present in the mother liquor, a part of the phosphorous acid is substituted in the above ratio. It is presumed that it exists.

Therefore, the potassium phosphite zinc phosphite compound according to the present invention is a reaction product of the above raw materials, and preferably satisfies the formula 0.67≦x<0.98.0.2 <y'<1 .0<z
<1.3.3(1-x)≦! and O≦n≦1.3, and the organic phosphonic acid (salt) is present in an amount of at least 2% by weight based on phosphorous acid.

Therefore, the reaction ratio of each raw material in this reaction is:

Due to the above limitations on x, y, and z, the corresponding ratio is
a, b, c and d are naturally limited.

The reaction is usually carried out under normal pressure, and there is no need to pressurize it.The reaction is usually carried out in the range from normal temperature to about 100°C, and there is no need for cooling.

However, since the reaction rate is proportional to temperature, it takes 119 hours to complete the reaction at room temperature and about 1 hour at 100'Cj.

The dropping rate of the reaction stock solution may be slow when the reaction temperature is low, and fast when the reaction temperature is high. However, if the mixture is prepared too quickly, coarse particles will be formed and it will be necessary to grind them using a wet ball mill.

The reaction stock solution is a dispersion or an aqueous solution, and its concentration may be any concentration, but if the concentration is extremely low, a large amount of filtrate will be produced, and if the concentration is high, sufficient stirring of the reaction solution may be required. Since this may be difficult, it is desirable to select a concentration that is common sense in ordinary precipitation reactions.

Since the reaction is carried out with sufficient stirring, it is advisable to use a suitable stirrer and reaction vessel.

Under such appropriate reaction conditions, heating and stirring are performed as necessary to complete the reaction, and then the precipitate is separated by filtration by a conventional method, dried and pulverized to obtain a product. The product does not need to be washed with water, and the drying temperature is generally 100 to 2
It is best to carry out at 50°C.

The potassium phosphite zinc phosphite compound obtained in this way is a white product, and by selecting appropriate reaction conditions, a product with an appropriate particle size that can be used as a pigment without special particle size adjustment. There are advantages that can be obtained.

In addition, the anticorrosive pigment according to 1 of the present invention can be prepared by appropriately selecting the raw materials potassium compound, zinc compound, phosphoric acid compound, phosphorous acid compound, and organic phosphonic acid (salt). It is possible to obtain a white product that always contains the above ingredients. Note that as a rust preventive pigment, the effect is thought to be mainly due to the basic phosphorous acid zinc potassium phosphate, since the same effect is exhibited regardless of the composition or method. Therefore, in the present invention, the rust-preventing pigment containing a potassium phosphite zinc phosphate compound as an active ingredient is an organic phosphonic acid (salt) as a chemical substance.
Contains basic phosphate, zinc potassium phosphate [A] alone, or [A] and, for example, potassium phosphite, zinc phosphite,
A mixture with at least one of potassium phosphate, potassium organic phosphonate, zinc organic phosphonate, zinc phosphate, potassium phosphite 11r lead, potassium zinc organic phosphonate, potassium zinc phosphate, and an unreacted zinc compound; or It exists as a double salt, and in most cases, it is an amorphous white fine particle substance with virtually no peak observed in X-ray diffraction. When the amount of organic phosphonic acid (salt) used is small, X-ray diffraction lines such as unreacted zinc white may be observed in the product depending on the reaction.

Therefore, what composition or manufacturing method should be selected?
It may be determined as appropriate depending on the type of raw material and the specific use of the product.

The reason why the basic phosphorous acid zinc potassium phosphate compound containing organic phosphonic acid (salt) has excellent rust preventive properties in the rust preventive pigment of the present invention is not clear in detail, but it is probably due to the organic Since both phosphonic acids (IJA) have excellent metal chelating properties, it is presumed that they chelate with zinc ions, and this is what allows them to exhibit superior rust prevention properties compared to simple inorganic phosphoric acid. I think that the.

Next, the effects of the present invention are listed below.

1) The anti-rust pigment of the present invention has advantageous utility as a non-polluting, low-toxic white anti-rust pigment, and since it is white, the color can be adjusted freely, so it is possible to produce a compound paint with anti-rust effects. is possible.

2) When the anti-rust pigment of the present invention is used as a JIS paint using drying oil, which is a paint for structures, the anti-rust power is equivalent to that of conventional lead-based anti-rust pigment formulations, and especially when using chromium It has better anti-corrosion properties than acid-based anti-rust pigments.

3) Since the product of the present invention is non-polluting and has low toxicity, it is particularly useful in the food field, and can be used to protect food-related factories or food-related equipment such as refrigerators, freezers, microwave ovens, food cases, and other kitchen utensils. It can be used as a rust pigment or as an anti-rust paint for children's toys.

4) Utilization of synthetic resins as additives, catalysts, and reducing agents is also possible.

The present invention will be specifically explained below using Examples and Comparative Examples.

Examples 1 to 8 Potassium hydroxide in the amount shown in Table 1 was dissolved in 70 layers of water, and then 13.8 g of zinc oxide was added and stirred for 10 minutes. This is called liquid A. Meanwhile, 12.7g of phosphorous acid 75
After dissolving in Homi water and adding 0.7 g of orthophosphoric acid (75%) and the amount of organic phosphonic acid (salt) shown in Table 1, the total amount was reduced to 8
(Let it be 1+JL. Let this be liquid B.

Solution A was added dropwise over a period of about 90 minutes to Solution B, which was being stirred at a temperature of 50° C. or less, and after the completion of stirring, the mixture was stirred for an additional 10 minutes, and the temperature of the solution was raised to 70° C. to heat and ripen for about 1 hour.

After the reaction, the solid and liquid were separated according to a conventional method, and the temperature was about 120"C!
The mixture was dried for 1 hour and ground to obtain a white amorphous antirust pigment.

Table 1 (Note) l) HEDPBO$ Hafi Tough-1-Human 0 + Sea 1.1-diphosphonic acid 80% aqueous solution 2) NTP50% is 50% aqueous nitrilotrismethylenephosponic acid solution 3) NTP-Na40χ Comparative Examples 1 to 3 Comparative Examples 1 to 3 of 40% aqueous solution of sodium nitrilotrismethyleneposboxate (Na is 4 in the structural formula) Comparative samples were obtained in the same manner as in Example 1. However, instead of the organic phosphonic acid (salt), the amount of organic phosphonic acid (salt) shown in Table 2 is not added, and EDTA, which is a typical chelating agent, is used.
It was used.

Table 2 Test Example 1 Next, the rust prevention test results of Examples 1 to 8 and Comparative Examples 1 to 3 are shown.

O paint method A paint was made with the following composition.

Antirust pigment 3.0 parts by weight Titanium dioxide (rutile type) 12.0 parts by weight Precipitated barium sulfate 32.0 parts by weight Vehicle (Note 1) 40.0 parts by weight Mineral spirit 12j, 0 parts by weight Dryer (Note 2) 1.0 parts by weight Note 1 Betsukosol 1334 [Dainippon Ink Chemical ■]
Nonvolatile content 50%, medium oil alkyd resin Note 2 Liquid dryer (JIS K-5891, Type 1 A
) The above blended raw materials and glass peas [GBI manufactured by Toshiba Glass
(03) 100g was placed in a 200m mayonnaise bottle and dispersed for 1 hour using a paint shaker to form a uniform coating.

0 Rust prevention test■-The paint produced by the method described above was applied to a cold-rolled steel plate [1] Wood test panel industrial vehicle JIS G3141, 5PCG-
3B, 1. OX70X 150■11] using a bar coater, apply one coat so that the film thickness after drying is 15% thick. After this, the rust prevention ability was evaluated by conducting a salt spray test according to JIS K5400 using 5% salt water (using a salt spray tester 5T-ISO-2 manufactured by Suga Test Instruments) without applying a top coat. did.

The results of the rust prevention test are shown in Table 3.

Table - (note) 1) Blank indicates one that does not contain antirust pigment.

2) Evaluation Performance was evaluated by observing the state of the test piece and using the following criteria.

l...Those with a 100% rust occurrence rate2...Those with a 75% rust incidence3...Those with a 50% rust incidence4...Those with a rust incidence of 25% Item 5: No blistering or rust Test Example 2 The rust pigments prepared in Examples 1 to 8 and Comparative Examples 1 to 3 and the commercially available rust preventive pigments (2 types) were tested as described below. According to the simple corrosion test, the corrosion degree (lldd) was 7[
The changes over time up to 1 were measured, and the results shown in Table 4 were obtained. Based on this conclusion, we investigated the relationship between I F+ and the degree of corrosion after 2 days and organic phosphorus Muli-1 sand.
Figure 1.

The graph shown in FIG. 2 was obtained.

Table 4 (Note) Commercial product A: Zinc chromate rust preventive pigment Commercial product B: Aluminum tripolyphosphate rust preventive pigment (Simple corrosion test method) 1) Test solution: 3 A test solution is prepared by adding 0.5 g of a test sample (rust-preventing pigment) to 500 g of a saline solution containing % by weight.

11) Test steel plate = 3h/m x 5h/m x 3
mats cold rolled steel plate (JIS-G-3141,5
PCG-B), and the surface is coated with water-resistant abrasive paper (JIS R8
253, CG320), washed with acetone and ethanol, dried, and left in a desiccator for at least 1 hour at room temperature before use.

Measurement method: Put the test liquid in a cylindrical glass container equipped with a cooling reflux device, and hang the test steel plate in the center of the container with a vinyl string. This was placed in a constant temperature water tank set at 50±2°C, and while the liquid was kept at 50°C, 0.5jL/win of air was blown through the gas dispersion tube.In this state, the test steel plate was taken out every 24 hours and the nylon Remove +1 kimono with a brush and wash with water, then use a brass brush to remove +1 kimono, wash with water, wash with ethanol, dry, and leave in a desiccator at room temperature for more than 1 hour, then measure the mold weight. change to 0
．． Weigh to 1 mg. From this, the degree of corrosion (mdd=mg/d+o''/day) is calculated from the difference in mass before and after the test.

The test is repeated twice, and the average value is taken as the measured value.

[Brief explanation of drawings]

FIGS. 1 and 2 are graphs showing the relationship between the amount of organic phosphonic acid (salt) added and the degree of corrosion in the anticorrosion pigment according to the present invention. Applicant Former Hon Kagaku Kogyo Co., Ltd. Agent Yutaka 1) Yoshio

Claims (3)

[Claims] (1) Zinc compounds, potassium compounds, sonic acid compounds,
A rust-preventing pigment characterized by containing as an active ingredient a zinc potassium sulfite 11-based compound produced by a reaction with a phosphorus-resistant compound and an organic phosphonic acid (salt). (2) Organic phosphonic acid (salt) is #q formula % formula % [wherein R is a lower alkyl group, m is θ ~ 3, n = 1 ~ 2,
Z represents hydrogen, an alkali metal, or an ammonium group] Aminoalkylenephosphonic acid represented by the general formula [wherein n is an integer of 1 to 3, Z is the same as the previous formula] Ethylenediaminetetraalkylenephosphonic acid represented by the general formula , Alkylmethane-1-hydroxy-1,1 represented by the general formula [wherein R is a hydrogen atom or a lower alkyl group, and Z has the same meaning as in the previous formula]
- One or two selected from diphosphonic acid or salts thereof
The rust-preventive pigment according to claim 1, which is a "socket" (2). (3) Claim 1 or 2, wherein the organic phosphonic acid (salt) is at least 2% by weight or more based on phosphorous acid.
Rust-preventing pigments listed in section.