JP2609547B2 - Zinc calcium phosphite, method for producing the same, and rust preventive paint containing the same - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a novel zinc calcium phosphite, a composition containing the same, a method for producing the same, and a novel rust preventive paint containing the same. It is.

[Conventional technology]

Zinc phosphite has been well known, but calcium zinc phosphite has not been known at all. Also, it was not known how zinc calcium phosphite could be produced.

Further, although it is well known that zinc phosphite has an effect such as rust prevention, zinc calcium phosphite has even lower toxicity, stability or excellent rust prevention. It was not known at all. Accordingly, there has been no rust preventive paint containing zinc calcium phosphite.

Conventionally, chromic acid compounds and lead compounds have been widely used as rust-preventive pigments, but since they have excellent rust-preventing power, they contain chromium and lead in their composition. , Its toxicity was a problem. For this reason, development of pigments that do not contain chromium or lead as non-polluting rust preventive pigments has been promoted, and metal phosphates such as silicon phosphate, titanium phosphate, and condensed aluminum phosphate, zinc phosphite, and barium phosphite have been developed. And metal phosphites such as manganese phosphite, and metal molybdates such as zinc molybdate and calcium molybdate have been studied.

Among them, the following technology is disclosed with respect to zinc phosphite, but zinc calcium phosphite is not disclosed yet.

Japanese Patent Application Laid-Open No. 50-50297 (JP-B-56-9951) discloses that a basic zinc phosphite represented by the following formula is used as a stain inhibitor, a fungicide and a flame retardant due to tannin on the surface of wood. It is disclosed as useful as such.

XZnO-ZnHPO ₃ (X = 1/2 to 10) Also, JP-A-58-84109 discloses that a zinc potassium phosphite-containing material represented by the following formula is useful as a pollution-free rust-preventive pigment. Is disclosed.

K ₂ Zn ₂ (HPO ₃ ) ₃ -lZnHPO ₃ -mZnO-nH ₂ O (l = 0 to 48, m = 0 to (l + 3), n = 0 to 51) Discloses that a zinc zinc phosphite complex represented by the following formula is superior in chemical stability and dispersibility to the basic zinc phosphite disclosed in the above-mentioned JP-A-50-50297. Have been.

[2Zn (OH) ₂ -ZnHPO ₃ ] -XZnO (X = 0 to 17) On the other hand, the mechanochemical reaction is described in JP-A-64-40.
No. 563 describes a rust-preventive pigment composition comprising aluminum dihydrogen tripolyphosphate, a lead compound and a zinc compound.In the production of the rust-preventive pigment composition, when a poorly soluble substance is selected as the lead compound, a mechanochemical reaction is carried out. It is disclosed that it is desirable to proceed with chemicals.

[Problems to be solved by the invention]

The non-polluting rust preventive pigments described above have poor paint stability when compounded as a substitute for conventional rust preventive pigments, and their rust preventive power is lower than conventional rust preventive pigments. Therefore, it is necessary to develop and mix a new stabilizer, and it is necessary to increase the amount of the stabilizer to achieve the same rust prevention effect as that of the conventional pigment.
Originally, some of the non-polluting rust-preventive pigments described above are expensive. Further, the development and addition of a new stabilizer and an increase in the amount of the pigment itself may increase the cost of the non-polluting rust-preventive paint.

An object of the present invention is to provide a rust-preventive pigment material having excellent paint stability and excellent rust-preventive power at a lower price than the above-mentioned conventional pollution-free rust-preventive paint.

[Means for solving the problem]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors provide a novel compound, a composition containing the same, a method for producing the same, and a rust preventive paint containing the same.

The novel compound is calcium zinc phosphite represented by the following formula, and a composition containing the zinc calcium phosphite and zinc phosphite or zinc phosphite and zinc oxide; Or, it is a calcium phosphite or a zinc phosphite-containing composition comprising calcium phosphite and calcium hydroxide.

CaZn (HPO ₃ ) ₂ -nH ₂ O (1) Here, n = 0 to 2 This zinc calcium phosphite has at least a first spacing d (Å) given by powder X-ray diffraction. Characterized by a table.

Further, the composition containing zinc calcium phosphite includes those represented by the following formula.

_{aCaZn (HPO 3) 2 -bZnHPO 3} -nH 2 O ...... (2) aCaZn (HPO 3) 2 -bZnHPO 3 -cZnO-nH 2 O ...... (3) aCaZn (HPO 3) 2 -bCaHPO 3 -nH 2 O (4) aCaZn (HPO ₃ ) ₂ -bCaHPO ₃ -cCa (OH) ₂ -nH ₂ O (5) where a, b, c are a / (b + c) ≧ 1/6 Satisfy relationship
Represents an integer within 10 and n represents the number of water molecules of crystallization.

Further, the method for producing the calcium zinc phosphite and the composition containing the same according to the present invention is characterized in that the zinc compound and the calcium compound are slurried with water after adding phosphorous acid, or Compound,
And, after the phosphite compound is slurried with water, it is wet-kneaded by mechanical means without heating, and contains the above-mentioned zinc calcium phosphite characterized by reacting mechanochemically and containing the same. This is a method for producing a composition.

In the production method according to the present invention, zinc compounds used include zinc oxide (ZnO), zinc hydroxide (Zn (O
H) ₂ ), zinc carbonate (ZnCO ₃ ), zinc phosphite (ZnHPO ₃ )
The calcium compounds include calcium carbonate (CaCO ₃ ), calcium oxide (CaO), calcium hydroxide (Ca (OH) ₂ ), calcium phosphite (CaHPO ₃ ), and the like. The phosphite compounds include zinc hydrogen phosphite (Zn (H ₂ PO ₃ ) ₂ ) and calcium hydrogen phosphite (Ca (H
₂ PO ₃ ) ₂ ) etc. are included.

The method of the present invention is characterized in that, without heating, ball mill, vibration mill, sand grind mill, wet kneading by mechanical means using a crusher, etc., to react mechanochemically. This is essentially different from the method disclosed in JP-A-64-40563 in which only a poorly soluble lead compound is mechanochemically reacted as an aid to a solution reaction.

Further, the rust-preventive paint containing calcium zinc phosphite according to the present invention is a zinc phosphite according to the present invention or a composition containing the same as a rust-preventive pigment, which is prepared by a usual method. Refers to the paint made into paint.

[Action]

In the method for producing a zinc calcium phosphite compound according to the present invention, in the mechanochemical reaction of a zinc compound, a calcium compound, phosphorous acid, etc., by what kind of action, zinc calcium phosphite excellent in rust prevention is obtained. It is unknown whether the compound is formed or not.However, during contact between solids, a high-pressure high-temperature point is instantaneously generated at the contact point, where energy is concentrated and a special reaction different from a solution reaction occurs. It is presumed that it is doing.

Further, in the rust preventive paint according to the present invention, the zinc calcium phosphite compound exhibits an excellent rust preventive effect by what kind of action is unknown, but somehow zinc phosphite and calcium phosphite It is presumed that a synergistic effect more than the additional effect is working.

〔Example〕

I. Production of zinc calcium phosphite Example 1 81.4 g of zinc oxide (ZnO), 10 calcium carbonate (CaCO ₃ )
0.1g is dispersed in 750ml of water to make a slurry, then 40%
An aqueous solution of phosphorous acid (410.0 g) was added over 1 hour with stirring to cause a reaction. After stirring for an additional hour, the reaction slurry was transferred to an alumina ball mill and wet-kneaded for 6 hours. After the wet kneading, the slurry is filtered, and the obtained filter cake is
Powder dried at 110 ° C for 24 hours (hereinafter referred to as “powder I”)
And

Example 2 99.4 g of zinc hydroxide (Zn (OH) ₂ ) and calcium oxide (C
aO) 112.2 g was dispersed in about 1200 ml of water to form a slurry, and 547.0 g of a 30% aqueous phosphorous acid solution was added thereto with stirring over 1 hour to cause a reaction. After stirring for another 1 hour, the reaction slurry was transferred to a vibration mill and wet-kneaded for 4 hours. After wet kneading, the slurry was filtered, and the obtained filter cake was heated at 110 ° C for 24 hours.
The powder was dried for a period of time to obtain a powder (hereinafter referred to as “powder II”).

Example 3 125.4 g of zinc carbonate (ZnCO ₃ ) and calcium hydroxide (Ca (O
H) ₂ ) 148.2 g, phosphorous acid (H ₃ PO ₃ ) 246.0 g, water about 500 ml
Was placed in a crusher and wet kneaded for 24 hours. After the wet kneading, the slurry was filtered, and the obtained filter cake was heated to 110 ° C.
For 24 hours to obtain a powder (hereinafter referred to as “powder III”).

Example 4 145.4 g of zinc phosphite (ZnHPO ₃ )
After 222.3 g of (OH) ₂ ) was dispersed in about 1500 ml of water to form a slurry, 410.0 g of a 40% aqueous phosphorous acid solution was added thereto with stirring for 1 hour to react. After further stirring for 1 hour, the reaction slurry was transferred to a sand grind mill and wet-mixed for 4 hours. After the wet kneading, the slurry was filtered, and the obtained filter cake was dried at 110 ° C. for 24 hours to obtain a powder (hereinafter referred to as “powder I”).
V ”).

Example 5 162.8 g of zinc oxide (ZnO) and calcium phosphite (CaHPO)
^{_{3 - 3/2 H 2 O}} ) 147.1g were mixed was placed in a kneader, was 80% phosphorous acid solution 102.5g was added over 1 hour while kneading the reaction. After further kneading for 1 hour, 300 g of the reaction product was transferred to an alumina ball mill, and about 300 ml of water was added, followed by wet kneading for 6 hours. After the wet kneading, the slurry was filtered, and the obtained filter cake was dried at 110 ° C. for 24 hours to obtain a powder (hereinafter referred to as “powder V”).

Example 6 162.8 g of zinc oxide (ZnO) and calcium hydroxide (Ca (O
H) ₂ ) 74.1 g, zinc hydrogen phosphite (Zn (H ₂ PO ₃ ) ₂ ) 22
7.4 g, hydrogen phosphite calcium _{(Ca (H 2 PO 3)} 2 -6H
₂ O) _310.2g, water about 500ml was 4 hours wet kneading placed in a vibration mill. After the wet kneading, the slurry was filtered, and the obtained filter cake was dried at 110 ° C. for 24 hours to obtain a powder (hereinafter referred to as “powder VI”).

Example 7 244.1 g of zinc oxide (ZnO) and 10 of calcium carbonate (CaCO ₃ )
0.1g is mixed and put in a kneader, and 80% phosphorous acid aqueous solution 307.5g
Was added over 1 hour while kneading, and reacted. One more
After kneading for an hour, 300 g of the reaction product was transferred to an alumina ball mill, and about 300 ml of water was added to perform wet kneading for 4 hours. After the wet kneading, the slurry was filtered, and the obtained filter cake was
The powder was dried at 24 ° C. for 24 hours to obtain a powder (hereinafter referred to as “powder VII”).

Example 8 162.8 g of zinc oxide (ZnO) and calcium hydroxide (Ca (O
H) ₂ ) 148.2 g was dispersed in about 1250 ml of water to form a slurry, and then 328.0 g of a 50% aqueous phosphorous acid solution was added over 1 hour with stirring to cause a reaction. After stirring for an additional hour, the reaction slurry was transferred to an alumina ball mill and wet-kneaded for 6 hours. After the wet kneading, the slurry was filtered, and the obtained filter cake was dried at 110 ° C. for 24 hours to obtain a powder (hereinafter referred to as “powder V
III ”).

Comparative Example 1 Zinc oxide (ZnO) 81.4 g, calcium hydroxide (Ca (OH)
₂ ) 74.1 g was dispersed in about 600 ml of water to make a slurry,
After heating to ° C, 328.0 g of a 50% aqueous solution of phosphorous acid was added over 1 hour with stirring to cause a reaction. After further stirring for 3 hours while keeping the temperature at 80 ° C., the slurry was filtered, and the obtained filter cake was dried at 110 ° C. for 24 hours to obtain a powder (hereinafter referred to as “powder IX”).

Tables 2 and 3 show the molar ratios of the raw materials of the powders I to IX obtained in Examples 1 to 8 and Comparative Example 1, the substances identified by X-ray diffraction, the molar ratios of the compositions by chemical analysis, and the average particles. Indicates the diameter.

However, the meanings of the symbols in this table are as follows.

CH = Ca (OH) ₂ ZO = ZnO HP = H ₃ PO ₃ ZC = CaZn (HPO ₃ ) ₂ CP = CaHPO ₃ ZP = ZnHPO ₃ ＝= Existence of X-ray diffraction.

Δ = X-ray diffraction result The presence was slightly recognized.

-= X-ray diffraction result No presence was observed.

However, the symbols have the same meanings as in Table 2.

From Tables 2 and 3, in Examples 1 to 8, the intended single-component composition, two-component composition, or three-component composition was obtained by changing the raw material molar ratio. And no impurity component was found. Comparative Example 1
As a result, a melting reaction and crystallization were performed, the reaction was not completed, and unreacted substances, which tend to occur in a solid solution reaction, remained.

II. Paint preparation and rust prevention test Powders I to VIII obtained in Examples 1 to 8 were prepared at the following compounding ratio, and dispersed for 1 hour using a sand mill together with 100 g of glass beads (Φ1.5 mm) for coating. And paints I to VIII were obtained, respectively. There is no particular problem in making the paint,
Also, there was no particular problem in the stability of the obtained paint.

Rust prevention pigment (powder I-VIII) 6.1 parts by weight Titanium dioxide (rutile type) 6.0 parts by weight Calcium carbonate 6.7 parts by weight 13.6 parts by weight Precipitable barium sulfate 6.7 parts by weight Resin 55.6 parts by weight Water 5.3 parts by weight Used here The resin used was a water sol CD-540 manufactured by Dainippon Ink and Chemicals, Inc., with a nonvolatile content of 39.2%.
Is a water-soluble epoxy ester resin.

For comparison, a commercially available zinc chromate rust preventive pigment (Zinc Chromate JWK-5114 CZP) was used as the above rust preventive pigment.
Type) (powder X), titanium dioxide (rutile type) (powder
XI), zinc phosphite (powder XII), calcium phosphite (powder XIII), and zinc phosphate (powder XIV) were each formed into a paint by the above-mentioned method to obtain paints X to XIV.

Paints I-VIII and paint X thus obtained
~ XIV was applied once on a cold-rolled steel plate JIS G3141 SPCC-SB 1.0 × 70 × 150 mm manufactured by Nippon Test Panel Kogyo Co., Ltd. using a bar coder so that the film thickness after drying was 30 μm. . Thereafter, it was dried at room temperature for one week, and without overcoating, salt spray tester ST-ISO-3 manufactured by Suga Test Instruments Co., Ltd.
Was used to perform a salt spray test with 5% saline to test the rust prevention of each paint. The results are shown in Table 4.

In this table, the evaluation numbers indicate the following results.

1 = 100% rust generation 2 = 75% rust generation 3 = 50% rust generation 4 = 25% rust generation 5 = No blistering or rust generation From Table 4, it is recognized that the zinc calcium phosphite according to the present invention has a rust-preventing power equal to or higher than that of zinc chromate conventionally used as a rust-preventive pigment.

〔The invention's effect〕

The zinc calcium phosphite according to the present invention, the method for producing the same, and the paint containing the same have the above-mentioned constitution and properties, so that they are even less toxic than conventional non-polluting rust preventive paints, and are inexpensive. Thus, it is possible to provide a rust preventive paint having excellent paint stability and excellent rust preventive power.

Claims (3)

(57) [Claims] 1. A calcium zinc phosphite represented by the following formula:
And a zinc calcium phosphite-containing composition CaZn (HPO ₃ ) comprising the zinc calcium phosphite, zinc phosphite or zinc phosphite and zinc oxide, or calcium phosphite or calcium phosphite and calcium hydroxide _2- nH ₂ O (1) where n = 0 to 2 (2) after adding phosphorous acid to a slurry of a zinc compound and a calcium compound in water, or
The method according to claim 1, wherein the zinc compound, the calcium compound, and the phosphorous acid compound are slurried with water, wet-kneaded by mechanical means without heating, and reacted mechanochemically. 13. A method for producing zinc calcium phosphite according to the above item and a composition containing the same. 3. A rust preventive paint containing zinc calcium phosphite according to claim 1.