JP3513774B2 - Zinc strontium phosphite anticorrosive paint - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a zinc strontium phosphite pigment which is not toxic to the human body and which has an excellent anticorrosion effect, and an anticorrosion paint using the same. .

[0002]

2. Description of the Related Art Conventionally, chromic acid compounds and lead compounds have been widely used as rust preventive pigments. Toxicity has become a problem. Therefore, as a pollution-free rust preventive pigment, the development of rust preventive pigments that do not contain chromic acid or lead has been promoted, and metal phosphates such as zinc phosphate, condensed phosphates such as aluminum tripolyphosphate, and zinc phosphite. , Phosphites such as aluminum phosphite and molybdates such as zinc molybdate have been investigated. However, none of these compounds has a rust preventive property comparable to that of a chromic acid compound or a lead compound.

On the other hand, various studies have been made on the characteristics of phosphite compounds. Japanese Examined Patent Publication No. 56-9951 discloses that basic zinc phosphite is useful for suppressing spots caused by tannin on the surface of wood, preventing mold, and imparting flameproofness. There is.

Further, improvement of the rust preventive property of this phosphite compound has been studied, and it is disclosed in JP-A-58-84109.
JP-A-58-58 discloses that potassium zinc phosphite is useful as a pollution-free anticorrosive paint.
Japanese Patent No. 194725 discloses that a zinc hydroxyphosphite complex is superior to basic zinc phosphite in chemical stability and dispersibility. In addition, JP-A-5
JP-A 9-204663 discloses that basic potassium zinc phosphite is particularly useful as a pollution-free rust preventive coating material.

The inventors of the present invention have also disclosed in Japanese Unexamined Patent Publication No. 3-1114.
JP-A No. 3-285808 discloses that zinc calcium phosphite has excellent rust preventive properties.
In the gazette, it was disclosed that plate-like crystals of calcium phosphite have a particularly excellent rust preventive property. In addition, JP-A-5
Japanese Patent No. 339004 also discloses that zinc calcium phosphite has an excellent rust preventive property. Furthermore, in the above-mentioned JP-A-3-285808 and JP-A-6-2169, in order to reduce the cost in the production of phosphorus calcium zinc oxyate such as zinc calcium phosphite, the following A method of utilizing calcium phosphite produced as a by-product in the production of sodium phosphate is disclosed.

[0006]

The above-mentioned pollution-free pigments up to zinc calcium phosphite have low paint stability and their rust preventive properties when used as a substitute for conventional rust preventive pigments. It was lower than conventional rust preventive pigments. Therefore, it is necessary to add a new stabilizer, and since the same rust preventive effect as that of the conventional rust preventive pigment is obtained, the amount of the pigment and the stabilizer is large and the cost is high. On the other hand, the appearance of a pigment having a higher rust preventive property than that of the zinc calcium phosphite pigment invented to solve such a problem was also expected. The problem to be solved by the present invention is
It is about fulfilling such expectations.

[0007]

In order to solve the above-mentioned problems, the inventors of the present invention include an anticorrosive paint containing a pigment composed of crystals of zinc strontium phosphite shown in Chemical formula 1 (hereinafter "First invention"), manganese, iron, cobalt, nickel, and 1 selected from the group consisting of copper
Phosphites, phosphites double salts, phosphates of one or more metals,
Phosphoric acid double salt, oxide or hydroxide 0.1% by weight
To 50% by weight and a compound compound consisting of 50% by weight to 99.9% by weight of zinc strontium phosphite shown in Chemical formula 1, zinc strontium phosphite type rust preventive pigment (hereinafter referred to as " 2)), and a zinc phosphite strontium-based rust preventive pigment according to the 2nd invention (hereinafter referred to as "3rd invention").

[Chemical 1]

The zinc strontium phosphite crystal according to the first aspect of the invention generally has the chemical formula 1SrmZn (HPO ₃ ) ₂
NH ₂ O (where, l = 0.1-1, m = 0.1
1, n = 0 to 2). And l =
When m = 1, the plane spacing [d in the powder X-ray diffraction
(Å)] is 6.90, 3.75, 3.57, 3.45,
3.38, 3.33, 3.24, 3.06, 3.04
The values of 3.00, 2.80, 2.61, 2.49, and 2.24 are shown. Further, such a crystal structure is maintained even if the values of l and m are slightly changed.

The pigment composed of zinc strontium phosphite crystals according to the first invention is produced by using a zinc compound, a strontium compound, and phosphorous acid or a phosphorous acid compound as a raw material. The zinc compound may be any one as long as it reacts with phosphorous acid or a phosphorous acid compound to form zinc phosphite, but a different acid radical difficult to remove in the reaction product. It is preferable to use zinc oxide or zinc carbonate in order to prevent the residue from remaining. Also, the strontium compound used may be any one as long as it reacts with phosphorous acid or a phosphorous acid compound to produce strontium phosphite, but it is difficult to remove in the reaction product. It is preferable to use strontium oxide, strontium carbonate, or strontium hydroxide in order to prevent such different acid radicals from remaining. It is phosphorous acid or a phosphorous acid compound that reacts with these zinc compounds and strontium compounds. As the phosphite compound, any compound may be used so long as it reacts with these zinc compounds and strontium compounds, so that unnecessary foreign metals and bases do not remain in the reaction product. In order to
It is preferable to use phosphorous acid, zinc hydrogen phosphite, or strontium hydrogen phosphite.

As the method for reacting the above-mentioned zinc compound, strontium compound and phosphorous acid or phosphorous acid compound, any method such as wet reaction or dry reaction, batch method or continuous method may be used. Moreover, each raw material may be added in any order. In the wet reaction, the solid raw material is used as a slurry, but it is preferable to use a homogenizer, a ball mill or the like in advance to perform a strong shearing treatment to use it as a fine slurry. Furthermore, after the initial reaction, a ball mill or a crusher is used. It is preferable to knead with a machine to complete the reaction. Also in the dry reaction, it is preferable to complete the reaction by kneading with a ball mill, a crusher or the like after the initial reaction. A suitable reaction temperature for the wet reaction is from room temperature to 90 ° C.
The reaction time is usually 30 minutes to 24 hours. After completion of the reaction, in order to improve dispersibility in the resin and coating stability, higher fatty acid or its derivative, or SiO ₂ , Al ₂
The surface can be treated with a metal oxide such as O ₃ . For example, zinc strontium phosphite surface-treated with zinc stearate can be obtained by mixing 1 to 5% by weight of zinc stearate and kneading with a ball mill, jet mill or the like. Further, zinc strontium phosphite surface-treated with SiO ₂ can be obtained by neutralizing with an acid after adding a soluble silicate such as sodium silicate. The reaction slurry thus obtained is filtered and the cake obtained is dried and ground.

The product obtained by such a reaction may remain unreacted raw materials or undesired reaction products due to differences in the blending ratio of the raw materials. For example, zinc oxide may be used as the raw material. , Strontium carbonate, and when using phosphorous acid, if within the range shown in the following formula,
It does not significantly affect the properties and rust resistance of the obtained zinc strontium phosphite. Where a, b, and c are the inequalities a / (b + c)
Represents an integer within 10 that satisfies the relation ≧ 1/6, and l =
0.1-1, m = 0.1-1, and n = 0-2.

The composite compound according to the second aspect of the present invention is a zinc compound such as zinc oxide or zinc carbonate, and strontium oxide or strontium carbonate, similar to the method for producing a pigment comprising zinc strontium phosphite crystals according to the first aspect. ,
Along with strontium compounds such as strontium hydroxide, manganese, iron, cobalt, nickel, and compounds such as oxides and hydroxides of one or more metals selected from the group consisting of copper, phosphorous acid, or, It is also produced by reacting with a phosphite compound, but separately produced strontium zinc phosphite is added to one or more metals selected from the group consisting of manganese, iron, cobalt, nickel, and copper. Phosphite, phosphorous acid double salt, phosphoric acid salt, phosphoric acid double salt, etc. may be added and mixed.

In the composite compound according to the second invention, manganese mixed with zinc strontium phosphite,
The amount of compounds such as iron, cobalt, nickel and copper is
It is necessary to be 0.1 to 50% by weight, and in particular, 0.1.
It is preferably from 2 to 20% by weight. If it is less than 0.1% by weight or exceeds 50%, it is impossible to obtain a pigment having a high rust preventive property.

The rust-preventive coating material according to the first invention may be of any type as long as it is made into a coating material by using a pigment composed of zinc strontium phosphite crystals, and is generally added as necessary. It may contain other pigments, resins, drying oils, dispersants, solvents and the like.

The rust preventive paint according to the third invention may be any paint as long as it is made into a paint using the zinc strontium phosphite rust preventive pigment according to the second invention.
Generally, it contains other pigments, resins, drying oils, dispersants, solvents and the like added as necessary.

[0016]

The function of the pigment comprising zinc strontium phosphite crystals according to the first aspect of the present invention has better anticorrosive properties than that of zinc calcium phosphite, but it is not clear yet. Since the standard electrode potential of strontium is lower than that of calcium, and therefore the ionization tendency of strontium is higher than that of calcium, strontium zinc phosphite has a solubility in water that has permeated the coating film.
It is considered to be higher than zinc calcium phosphite, capable of trapping more dissolved ions in permeated water, and further forming a strong film on the surface of iron of the base material.

It is not known in detail how the zinc strontium phosphite pigment according to the second aspect of the invention has a superior rust preventive property to the pigment composed of a single zinc strontium phosphite crystal. But for the time being, manganese,
Metal compounds such as iron, cobalt, nickel and copper have not only rust prevention property themselves, but also react with a part of components of the oxidative polymerization type resin in the paint to form metal soap, etc.,
It is considered that it acts not only as a curing catalyst for the resin in the paint but also as a catalyst when forming a film on the surface of iron, thereby forming a denser and stronger film.

[0018]

【Example】

1. Production of Pigment [Example 1] 81.4 g of zinc oxide (ZnO), 147.6 g of strontium carbonate (SrCO ₃ ) and 1000 parts of water.
It was dispersed in ml and passed through a colloid mill to make it fine. After heating this slurry to 50 ° C., 547 g of 30% phosphorous acid solution
Was stirred for 1 hour and reacted. Furthermore,
After stirring for 2 hours, the reaction slurry was filtered, and the obtained filter cake was dried at 110 ° C. for 24 hours to obtain a powder (hereinafter referred to as “pigment 1”).

Example 2 Zinc oxide (ZnO) 83.3
g, strontium carbonate (SrCO ₃ ) 147.6 g,
2.7 g of nickel carbonate (NiCO ₃ ) and water 1500 m
1 and dispersed in a colloid mill to make it fine. After heating this slurry to 50 ° C., 560 g of a 30% phosphorous acid solution was added with stirring for 1 hour to cause a reaction. Furthermore, 2
After stirring for an hour, the reaction slurry was filtered, and the obtained filter cake was dried at 110 ° C. for 24 hours to obtain a powder (hereinafter referred to as “pigment 2”).

Example 3 Zinc carbonate (ZnCO ₃ ) 13
2.6 g, strontium carbonate (SrCO ₃ ) 147.
6 g and nickel carbonate (NiCO ₃ ) 6.9 g were mixed and placed in a kneader, and 217 g of 80% phosphorous acid solution was added and reacted for 1 hour while kneading. Furthermore, after kneading for 1 hour, 300 g of the reaction product was transferred to an alumina ball mill, 500 ml of water was added, and the mixture was wet kneaded for 6 hours. The reaction slurry is filtered and the resulting filter cake is washed with 110
The powder was dried at 24 ° C. for 24 hours to obtain a powder (hereinafter referred to as “pigment 3”).

Example 4 Zinc oxide (ZnO) 83.6
g, strontium oxide (SrO) 103.6 g, manganese hydroxide (Mn (OH) ₂ ) 2.4 g, water 500 m
1 to make a slurry. This slurry is heated to 50 ° C.
The mixture was added to 1680 g of a 10% phosphorous acid solution that had been heated to 1 hour with stirring over 1 hour. Furthermore, after stirring for 1 hour,
The reaction slurry was transferred to an alumina ball mill and wet-kneaded for 6 hours. The reaction slurry was filtered, and the obtained filter cake was dried at 110 ° C. for 24 hours to obtain a powder (hereinafter referred to as “pigment 4”).

Example 5 Zinc Carbonate (ZnCO ₃ ) 14
2.2 g, strontium carbonate (SrCO ₃ ) 147.
6 g and 15.4 g of manganese carbonate (MnCO ₃ ) were dispersed in 1500 ml of water using a homogenizer. After stirring for 1 hour, 372 g of a 50% phosphorous acid solution was stirred, and 1
It was added over a period of time and reacted. Furthermore, after stirring for 3 hours, the reaction slurry was filtered, and the obtained filter cake was dried at 110 ° C. for 24 hours to obtain a powder (hereinafter referred to as “pigment 5”).

Example 6 Zinc oxide (ZnO) 81.4
g, strontium carbonate (SrCO ₃ ) 147.6 g
Was dispersed in 1000 ml of water and passed through a colloid mill to be finely divided. After heating the slurry to 50 ° C., 547 g of a 30% phosphorous acid solution was added with stirring for 1 hour for reaction. After further stirring for 2 hours, the reaction slurry is filtered,
The filter cake obtained was dried at 110 ° C. for 24 hours to give a powder. To 95 g of this powder, nickel phosphate (N
2.5 g of iHPO ₄ and manganese phosphate (MnH
2.5 g of PO ₄ was dry mixed to obtain powder (hereinafter referred to as “Pigment 6”).
I got).

[Comparative Example] As pigments for comparison of rust prevention and the like, commercially available zinc chromate pigment (ZPC type) pigment (hereinafter referred to as "Pigment 7"), zinc phosphate pigment (hereinafter referred to as "Pigment 8") , A condensed aluminum phosphate pigment (hereinafter referred to as "Pigment 9"), a zinc molybdate pigment (hereinafter referred to as "Pigment 10"), and talc (hereinafter referred to as "Pigment 1").
1 ”) was prepared.

2. Production of Water-Soluble Epoxy Ester Resin-Based Paint The pigments 1 to 11 obtained in Examples 1 to 6 and Comparative Example were adjusted with the compounding ratios shown in Table 1, and glass beads (Φ1.
5 mm) and 100 g were dispersed in a sand mill for 1 hour to form coating materials, and coating materials A1 to A11 were obtained. In addition,
The resin used here is Watersol CD-540 manufactured by Dainippon Ink and Chemicals, Inc., which is a water-soluble epoxy ester resin having a nonvolatile content of 39.2%. There were no particular problems in producing coating materials A1 to A11 using pigments 1 to 11, and there were no particular problems in the stability of the obtained coating materials A1 to A11.

[0026]

[Table 1]

3. Preparation of Permanent Dry Acrylic Resin-Based Paint The pigments 1 to 11 obtained in Examples 1 to 6 and Comparative Example were adjusted with the compounding ratios shown in Table 2, and glass beads (Φ1.
5 mm) and 100 g were dispersed in a sand mill for 1 hour to form coating materials, and coating materials B1 to B11 were obtained. In addition,
The resin used here is ACRYDIC A-126-50 manufactured by Dainippon Ink and Chemicals, Inc., with a nonvolatile content of 50%.
It is an acrylic resin. Paint B using Pigments 1-11
There was no particular problem in producing 1 to B11, and there was no particular problem in stability of the obtained coating materials B1 to B11.

[0028]

[Table 2]

4. Anticorrosion test Paints A1 to 11 and B1 to B1 thus obtained
11 is a cold-rolled steel plate (J
IS G3142) 1.0 × 70 × 150 mm was coated once with a bar coater so that the film thickness after drying was 30 μm. Then, it was dried at room temperature for 1 week, and a salt spray test with 5% saline was conducted using a salt spray tester (ST-ISO-3) manufactured by Suga Test Instruments Co., Ltd. without overcoating, and each paint Was tested for rust resistance. The results are shown in Table 3. In Table 3, the evaluation numbers show the following results. 1 = 100% rust generation 2 = 75% rust generation 3 = 50% rust generation 4 = 25% rust generation 5 = No blister or rust

[0030]

[Table 3]

As shown in Table 3, the paint containing the pigment comprising zinc strontium zinc phosphite crystals according to the present invention has the same or more rust preventive properties as the paint containing the commercially available zinc chromate pigment. Further, phosphorus phosphite comprising strontium zinc phosphite according to the present invention and phosphite, phosphate, etc. of one or more metals selected from the group consisting of manganese, iron, cobalt, nickel and the like. It can be seen that the coating material containing the zinc strontium acid pigment has more excellent rust prevention.

[0032]

The pigment according to the present invention comprising zinc strontium phosphite crystals, zinc strontium phosphite and one or more metals selected from the group consisting of manganese, iron, cobalt, nickel and copper. Zinc strontium phosphite pigment consisting of phosphite, phosphate, etc.,
In addition, the paint containing these pigments has no pollution and low toxicity because it has the above-mentioned constitution and action, and has excellent rust preventive property and paint stability, so it is a paint for tableware, toys, ship bottoms, etc. As you can use it with confidence.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-5-339004 (JP, A) JP-A-3-111457 (JP, A) JP-A-59-204664 (JP, A) Inorganic Chemistry, 1990 Year, Vol. 29, No. 5, p958-963 (58) Fields investigated (Int. Cl. ⁷ , DB name) C01B 25/163 CA (STN)

Claims (3)

(57) [Claims] 1. A rust preventive paint comprising the pigment consisting of crystals of zinc strontium phosphite shown in Chemical formula 1. 2. A phosphite, a phosphorous acid double salt, a phosphoric acid salt, a phosphoric acid double salt, and an oxidation of one or more metals selected from the group consisting of manganese, iron, cobalt, nickel, and copper. object,
Alternatively, 0.1% to 50% by weight of hydroxide and
50% by weight of strontium zinc phosphite to 9
Zinc strontium phosphite-based rust preventive pigment containing a composite compound of 9.9% by weight 3. A rust preventive paint comprising the zinc strontium phosphite rust preventive pigment according to claim 2.