JPH0158224B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

The present invention aims to provide a novel pigment that has an excellent anticorrosion effect on metals and also has effective performance as a fungicide and a flame retardant.

[Prior Art] Conventionally, chromic acid pigments and lead pigments have been mainly used as anticorrosion pigments, but the toxicity of chromium and lead has become a problem, so non-toxic or low toxicity zinc phosphate, zinc molybdate, Molybdenum calcium, barium metaborate, etc. are used. However, all of these have insufficient effects compared to the anticorrosive chromic acid pigments.

[Summary of the problem of the invention and the solution]

As a result of various studies on pigments with excellent performance that can replace these pigments, the present inventors have found pigments selected from phosphoric acid compounds, boric acid compounds, and if necessary, silicic acid compounds, and compounds of Ca, Sr, and Ba. When a product having a specific ratio of composition is used as a pigment by reacting with one or more of the following, it has excellent metal corrosion resistance, adhesion to metal plates, and water resistance, and is effective in preventing blistering of the paint film. The present invention was obtained by discovering that this material has the following characteristics. As will be described in detail later, the above-mentioned product of the present invention is not just a blended composition, but forms a novel composite oxide, and the present invention is characterized by the use of this substance as a pigment. It is.

[About anti-corrosion performance]

Next, before explaining the configuration of the present invention, the anticorrosion performance for metals will be described. Compounds of alkaline earth metals, Zn, Al, etc., and phosphoric acid have the performance as anticorrosion pigments, and zinc phosphate, aluminum phosphate, etc. are used, but their anticorrosion mechanism is due to their presence in the coating film. A part of the compound becomes solubilized due to the influence of moisture, and free phosphoric acid is generated in the anode area of the metal surface of the coating base.Fe ²⁺
It is said to maintain its anticorrosion effect because it reacts with ions to form a poorly soluble precipitated film. On the other hand, similar to the case of phosphates, metal compounds with boric acid become soluble due to the influence of moisture in the coating film, and the buffering action keeps the base metal surface slightly alkaline, forming a stable oxide film. do. In addition, the metal ions used as counterions, such as Ba, form metal chains with the fatty acids in the coating vehicle, which reduces the permeability of moisture to the base metal surface and prevents the occurrence of rust. It is explained. What is important here is that the items required for corrosion protection include items related to the solubility of anticorrosion pigments, such as water resistance and hot water resistance, and items related to the protection of the base metal surface, such as paint film adhesion and corrosion resistance. There are related matters. For example, in a borate and phosphate anticorrosive pigment system, when used in areas where the molar ratio of B ₂ O ₃ /P ₂ O ₅ is large, the adhesion of the coating improves, but because the solubility of the borate compound is high, , the water resistance of the coating film will be poor. Conversely, if used in a formulation where the molar ratio of B ₂ O ₃ /P ₂ O ₅ is small, the water resistance will improve due to the influence of the low solubility of the phosphate compound, but the adhesion will be poor. will be inferior.

[Summary of structure and effects of the invention]

In searching for new pigments, the present inventors conducted research to find a substance that retains the anticorrosive properties of phosphates and borates, and can exhibit these properties more markedly depending on the purpose. The present invention was based on the discovery that a product obtained not simply by mixing acid and borate anticorrosive pigments but by reacting the raw materials and containing both components in a specific proportion meets this purpose. It is ivy. That is, the first pigment according to the present invention is obtained by reacting one or more selected from Ca, Sr, and Ba compounds with a phosphoric acid compound and a boric acid compound, and has a composition of MeO.xP ₂ O ₅・yB ₂ O ₃・nH ₂ O (here, Me represents Ca, Sr, Ba, x, y,
n is each 1 mole of MeO, x is 0.1 to 0.9,
y is 0.1 to 0.9, n is 0 to 2), and y/x is 0.1 to 9. The second pigment contains silicon in the above reaction system. _The product obtained by adding _an acid _compound , _the composition of which _{is MeO} . ,y,z,n
are respectively for 1 mole of MeO, x is 0.1 to 0.9,
y is 0.1 to 0.9, z is 0.8 or less, and n is 0 to 2), and y/z is 0.1 to 9. This new pigment shows a new diffraction pattern that is different from the respective X-ray diffraction patterns of the metal compound of phosphoric acid and the metal compound of boric acid, and the product forms a new composite oxide that is different from a simple mixture. It shows that there is. Next, the anticorrosion performance of the pigment of the present invention and a composition containing a phosphate and a borate will be compared and explained with reference to the accompanying drawings. FIG. 1 is a graph illustrating the relationship between the composition ratio, water resistance, and corrosion resistance of a composition in which the pigment of the present invention and a comparative pigment are blended into a water-soluble melamine/alkyd resin paint. That is, a compound having the composition BaO xP ₂ O ₅ yB ₂ O ₃ 0.2SiO ₂ 0.7H ₂ O was used as the pigment of the present invention, and a barium compound of phosphoric acid/silicic acid and a boric acid/silicic acid were used as the comparative pigments. The water resistance of the corresponding composition was determined by using a mixture of barium compounds as sample compositions mixed in the resin paint, and varying the molar ratio of phosphoric acid (x) and boric acid (y) in the composition. The graph explains the status of corrosion resistance and water resistance: 〇 (product of the present invention);
● (mixture product), corrosion resistance is indicated by △ (invention product), ▲ (mixture product). The test method and other conditions are as described below. As is clear from this figure, the pigment of the present invention is
It can be seen that over almost the entire range of B ₂ O ₃ /P ₂ O ₅ (y/x) from 0.1 to 9, both corrosion resistance and water resistance are far superior to the mixed product.
And this superiority is due to the fact that y/x is
0.25 to 2.5, y/x is 0.5 to 4 for corrosion resistance.
This is particularly noticeable in the range of . Next, the second invention is a complex oxide pigment in which silicic acid is introduced and reacted with a system of phosphoric acid and boric acid. SiO ₂ has the effect of further reducing the solubility of metal compounds such as phosphates and borates in water, but on the other hand, its anti-corrosion performance is slow-acting, so taking these into account, the molar ratio to the metal should be 0.8 or less. limited to. From the above, anticorrosive pigments with low solubility are suitable for paint systems that require particularly water resistance, and B ₂ O ₃ /
It is desirable that the molar ratio of P ₂ O ₅ is 0.25 to 2.5 and the molar ratio of SiO ₂ /MeO is 0.15 to 0.8. In addition, anti-corrosion pigments with appropriate solubility are particularly suitable for paint systems that require good adhesion to metal substrates.
The molar ratio of B ₂ O ₃ /P ₂ O ₅ is 0.5 to 4, and SiO ₂ /MeO
It is desirable that the molar ratio is within the range of 0 to 4.4. When B ₂ O ₃ /P ₂ O ₅ is less than 0.1, as shown in the figure, there is no superiority in corrosion resistance over dry mixtures of barium compounds of phosphoric acid/silicic acid and barium compounds of boric acid/silicic acid. . Moreover, when the molar ratio of B ₂ O ₃ /P ₂ O is greater than 9, the superiority over dry mixed products in terms of water resistance is lost. Therefore, the novel pigment that has both good water resistance and corrosion resistance, which is the object of the present invention, has the above compositional formula:
It is obtained when the molar ratio of B ₂ O ₃ /P ₂ O ₅ is in the range of 0.1 to 9. Such remarkable effects of the pigment of the present invention are basically derived from the fact that a complex oxide obtained by reacting a specific metal compound, a phosphoric acid compound, and a boric acid compound is used as a pigment. As mentioned earlier, phosphoric acid compounds and boric acid compounds have the effect of forming a poorly soluble precipitate film by reacting with Fe ²⁺ ions generated in the anode region of the metal surface of the coating base, and also have the effect of forming a poorly soluble precipitate film. In metal compounds, the metal combines with fatty acids in the paint film vehicle to form a metal compound, which has the effect of preventing moisture from permeating into the metal base surface.As a result of the accumulation of these effects, pigments The present invention has demonstrated that the anti-corrosion performance of oxides is much higher in the case of composite oxides in which the above compounds are chemically combined than in the case of using them in the form of mixtures. be. Next, the test method and other conditions that were the basis for the corrosion resistance and water resistance shown in the drawings will be explained. (1) The composition and test method of the water-soluble melalamine alkyd resin paint used were the same as those in the examples below. (2) Water resistance test method is JISK5400 7.2 (water resistance)
Based on the following 5 grades (vertical axis in the figure), evaluation was made based on the state of blistering of the coating film after 5 days of immersion at 40°C. 5 Very good 4 Good 3 Somewhat good 2 Bad 1 Very bad (3) The corrosion resistance test method is based on JISK5400 7.8 (salt spray test), and is evaluated in 5 stages based on the condition of cross section blisters after 400 hours of testing. Did. The criteria are the same as (2). (4) The pigment of the present invention was prepared according to the method of Example 1 using sodium hexamethanate as the phosphoric acid compound. By changing the addition ratio of the raw materials, pigments having the x and y ratios shown in the figure were obtained. Its composition ratio is BaO.xP ₂ O _{5.yB 2} O _{3.0.2SiO 2} B.0.7H ₂ O. (5) For the mixed product, a pigment consisting of a barium compound of phosphoric acid and silicic acid and a pigment consisting of a barium compound of boric acid and silicic acid are prepared separately as shown below, and mixed in a dry process to form the x in the figure. , y. (a) Method for preparing a barium compound of phosphoric acid/silicic acid (i) Dissolve 38 g of sodium hexametaphosphate in 505 g of water. (ii) Prepare 7g of No. 1 sodium silicate (SiO ₂ B32%). (iii) Prepare 289g of barium sulfide solution (BaS12%). The solutions of (i), (ii), and (iii) above are heated to 50° C., and simultaneously added to a separately prepared pressure vessel while stirring and reacting. Then, the temperature was raised to 130°C, and the mixture was continuously stirred for 6 hours. The reaction solution was filtered using a Buchner funnel, the cake was washed with pure water, and the washed cake was dried and ground using a sample mill.

[Table] (b) Preparation method of barium compound of boric acid/silicic acid (i) Dissolve 44 g of borax (decahydrate) in 206 g of water. (ii) Prepare 7g of No. 1 sodium silicate (SiO ₂ 32%). (iii) Prepare 375g of barium sulfide solution (BaS12%). The solutions of (i), (ii), and (iii) above are heated to 50°C, and simultaneously added to a separately prepared pressure vessel while stirring and reacting. Then, the temperature was raised to 130°C, and the mixture was continuously stirred for 6 hours. The reaction solution was filtered using a Buchner funnel, the cake was washed with pure water, and the washed cake was dried and ground using a sample mill.

【table】

[Field of application of the present invention]

The novel pigment of the present invention is effective as an anticorrosion pigment in a wide range of coating systems. For example, solvent-based paints are used for oil-based, alkyd-based, aminoalkyd-based, acrylic-based, phenolic-based, epoxy-based, urethane-based, silicone-based, nitrocellulose-based, vinyl-based, and rubber-based paints. In water-based paints, it is used in water-soluble or water-dispersible alkyd, acrylic, and epoxy ester paints, and emulsion-type acrylic or acrylic-styrene paints, as well as resin-based paints for the purpose of protecting the base metal. Can be used without exception. Generally, anticorrosion pigments are added to metal paints to prevent corrosion of metal substrates, but adhesion to the metal substrate is required for coating film performance. It is also important not to deteriorate the water resistance of the coating film containing the anticorrosive pigment. That is, the adhesion to the metal base,
Water resistance of the coating film is also required.
In this regard, when the pigment of the present invention is blended into a paint, it satisfies both adhesion to the metal substrate and water resistance, and exhibits properties to prevent blistering of the paint film, making it extremely effective as an anticorrosive paint for metals. It is. The anticorrosion pigments currently in use can be categorized by their anticorrosion function: basic anticorrosion pigments, passive film-forming anticorrosion pigments, reducing anticorrosion pigments, metal-based anticorrosion pigments, and anticorrosion pigments that utilize the shape of pigment particles. . Basic anticorrosive pigments include lead-based pigments (lead red, lead zinc oxide, lead cyanamide, basic lead chromate) and boric acid-based pigments (barium metaborate, calcium borate, zinc borate, etc.), and they can be used to form a passive film. Forming anticorrosion pigments include chromic acid-based (zinc chromate, strontium chromate, etc.), molybdate-based (zinc molybdate, calcium molybdate, etc.), tungstic acid-based, phosphoric acid-based (zinc phosphate, aluminum phosphate, etc.) ) and organic metal salts (such as zinc salts of organic nitro compounds), and reducing anticorrosion pigments include metals (such as zinc powder and aluminum powder) and phosphorous acid-based pigments. Metal-forming anticorrosion pigments include lead-based, alkaline earth metal-based, and zinc-based pigments. Further, anticorrosion pigments using the shape of pigment particles include mica-like iron oxide and the like. The novel pigment of the present invention has the following effect as a basic anticorrosive pigment: the metal salts of Ca, Sr, and Ba are solubilized by the influence of water in the coating film, keeping the base metal surface slightly alkaline; It has the effect of forming a stable oxide film. Second, since the metals form a metal bond with the fatty acid in the coating vehicle, they have the effect of reducing the permeation and adhesion of moisture to the metal base surface and preventing rusting. Thirdly, phosphoric acid and boric acid have the effect of forming a passive film, and Fe ²⁺ generated in the metal surface anode region
It has the effect of forming a poorly soluble precipitate film by reacting with ions. Therefore, conventional basic anti-corrosion pigments, passive film-forming anti-corrosion pigments and metal-based anti-corrosion pigments, such as chromic acid-based, lead-based, phosphoric acid-based, molybdic acid-based, tungstic acid-based, boric acid-based and organometallic In paint systems in which salt-based anticorrosion pigments are used, the pigment of the present invention can be used alone or in combination with other anticorrosion pigments in the same manner as for those anticorrosion pigments, and it is also possible to reduce Even in paint systems in which anti-corrosion pigments and anti-corrosion pigments that utilize the shape of pigment particles are used, the anti-corrosion effect can be achieved by using them in combination. Furthermore, since the pigment of the present invention is white, one of its features is that, unlike chromic acid pigments, the paint can be colored arbitrarily.

[Flame retardant effect]

The novel pigment of the present invention effectively acts as a flame retardant when incorporated into plastics, rubber, paints and fibers. For example, plastics include vinyl chloride, polyester, polyolefin, polystyrene, epoxy, phenol, and acrylonitrile-butadiene-styrene resin (ABS).
It is used by adding it to etc. In rubber, it is used for chlorinated rubber, Hypalon, chlorinated polyethylene rubber, ethylene/propylene rubber, nitrile/butadiene rubber, etc. In paints, it is used in chlorinated rubber-based, vinyl chloride-based, alkyd-based, oil-based, phenol-based, and epoxy-based paints. Among fibers, it is used for polyvinyl chloride-based, polyamide-based, polyester-based, polyolefin-based, pore-nitrile-based, and polyvinyl alcohol-based fibers. Plastics for other uses requiring flame retardancy,
It can be used for rubber, paints and fibers without exception. The novel pigment of the present invention has a flame retardant function similar to that of conventional boric acid flame retardants (borax, boric acid, zinc borate, barium metaborate). That is, the pigment of the present invention and a chlorine-based flame retardant (chlorinated varaffin, etc.) are used together to coat the surface of a combustible material to make it flame retardant. During combustion, the pigment of the present invention is decomposed by the hydrogen chloride gas generated by the decomposition of the chlorine-based flame retardant, producing boric acid, which coats the surface of the combustible material to block oxygen and prevent combustion. be.
Furthermore, since the flame retardant effect is more effectively exhibited when antimony trioxide is used in combination, it is desirable to use the pigment of the present invention in combination with antimony trioxide and a chlorinated twisting agent.

[Mold-proofing effect]

The novel pigment of the present invention functions effectively as a fungicide when incorporated into paints, plastics, rubbers, adhesives, fibers, paper, cement, and the like. In paints, it can be used as a solvent-based additive. Solvent-based additives include acrylic, alkyd, oil-based,
For water-based paints such as cellulose-based, epoxy-based and urethane-based paints, vinyl acetate-based, acrylic-based,
Can be used for styrene-butadiene-based and alkyd-based paints. For rubber, it can be used for natural rubber, styrene-butadiene rubber, isoprene rubber, butadiene rubber, etc. Adhesives that can be used include starch, casein, vinyl acetate, rubber, cellulose, polyester, epoxy, urethane, and phenol adhesives. In addition, it can be widely used in paints, plastics, rubber, adhesives, fibers, paper, cement, etc. that require mold resistance. In recent years, the toxicity of fungicides has become a problem, and the use of highly toxic fungicides such as organic mercury compounds (such as phenylmercury acetate), organic tin compounds (such as bistributyltin oxide), and bentacrophenol has been restricted. , mildly toxic fungicides such as organic nitrogen sulfur, quinone, salicylic acid, organic copper, imidazoline, chlorotril, and boric acid fungicides are used. The pigment of the present invention has a fungicidal function similar to that of conventional boric acid-based fungicides (borax, barium metaborate, etc.), and can be applied to a wide range of uses as a mildly toxic fungicide. i.e. paint, plastic, rubber,
When blended into adhesives, fibers, paper, cement, etc., a portion of the composition becomes solubilized and becomes weakly alkaline due to the influence of water present in each composition, and has the function of inhibiting boric acid ions from oxidizing enzymes. The synergistic action of the two provides effective fungal protection. Borax has a high water solubility and deteriorates the water resistance of the composition in which it is blended, and does not have a long-lasting antifungal effect.However, the pigment of the present invention can appropriately adjust the water solubility, so the water resistance of the composition This makes it possible to maintain the anti-fungal effect for a long period of time without causing any damage.

[Production method of new pigment]

Next, a method for producing the pigment of the present invention will be explained. The raw materials are the following four types. The compounds of Ca, Sr, and Ba are preferably water-soluble compounds of each metal. For example, sulfides, chlorides, nitrates, acetates, etc. Furthermore, it may be an elemental metal, a metal oxide, or a metal carbonate, which is reactive with an aqueous solution of a phosphoric acid compound and a boric acid compound. The phosphoric acid compound is orthophosphoric acid, condensed phosphoric acid, or a potassium or sodium salt thereof. The boric acid compound is boric acid or its potassium or sodium salt. The silicic acid compound is silicic acid or its potassium or sodium salt. The above (first invention), or
(Second invention) Simultaneous reaction method in which each aqueous solution or suspension is prepared and simultaneously added to a separately prepared container while stirring and reacting, and [] and [] are reacted separately, and then both reaction solutions are reacted. There is an individual reaction mixing method for mixing. The temperature and concentration during the reaction are not particularly limited, but in industrial production it is advantageous to maintain the temperature at 100°C or lower, preferably 20 to 70°C, and as high a concentration as possible, preferably close to the saturation concentration of each raw material aqueous solution. The slurry obtained by the above simultaneous reaction method or individual reaction mixing method is put into a pressure vessel, and
Hydrothermal treatment is carried out at a temperature of 200° C. for at least 1 hour, preferably for about 4 hours while stirring. Alternatively, it is also possible to mix in a pressure vessel from the beginning and perform hydrothermal treatment at a temperature of 100 to 200°C. The reaction product is then filtered and washed with water in a conventional manner. Regarding the degree of water washing, it is appropriate to wash the water until the filtration specific resistance becomes approximately constant. Wash the cake at a temperature of 120℃ or higher, preferably 120-300℃
The pigment of the present invention can be obtained by drying the pigment and then pulverizing it.

【Example】

The present invention will be explained below with reference to Examples. Example 1 Prepare 750g of barium sulfide solution (BaS12%). 77g of trisodium phosphate (12 hydrate) and 173g of water
dissolve in Dissolve 44g of borax (decahydrate) in 20g of water. Prepare 14g of No. 1 sodium silicate (SiO ₂ 32%). Each of the above solutions was heated to 50°C and added simultaneously to a separately prepared pressure vessel while stirring and reacting. Then, the temperature was raised to 130°C, and the mixture was continuously stirred for 6 hours. The reaction solution was filtered through a Buchner funnel, and the cake was washed with 3 portions of pure water. The washed cake was then dried at 130°C for 16 hours and ground with a sample to obtain a pigment having the following compositional formula. BaO・0.2P ₂ O ₅・0.39B ₂ O ₃・0.20SiO ₂・0.63H ₂ O The composition of this pigment is shown in Table 1, and the corrosion resistance test results are shown in Tables 2 to 6. Example 2 750g of strontium sulfide solution (SrS8.5%)
Prepare. 77g of trisodium phosphate (washed 12 times) with 173g of water
dissolve in Dissolve 35g of borax (decahydrate) in 165g of water. Prepare 14g of No. 1 sodium silicate (SiO ₂ 32%). Each of the above solutions is heated to 50°C and reacted. Then, the temperature was raised to 130°C, and the mixture was continuously stirred for 6 hours. The reaction solution was filtered through a Buchner funnel, and the cake was washed with 3 portions of pure water. The washed cake was then dried at 130° C. for 16 hours and ground in a sample mill to obtain a pigment having the following compositional formula. SrO・0.30P ₂ O ₅・0.37B ₂ O ₃・0.19SiO ₂・0.59H ₂ O The composition of this pigment is shown in Table 1, and the corrosion resistance test results are shown in Tables 2 to 6. Example 3 (a) Preparation of Reactant A 375 g of barium sulfide solution (BaS 12%) is prepared. 77g of trisodium phosphate (12 hydrate) and 173g of water
dissolve in Prepare 7g of No. 1 sodium silicate (SiO ₂ 32%). Warm each of the above solutions to 50°C. These are simultaneously added to a separately prepared container while stirring and reacting. (b) Preparation of Reactant B Prepare 375 g of barium sulfide solution (BaS 12%). Dissolve 44g of borax (decahydrate salt) in 206g of water. Prepare 7g of No. 1 sodium silicate (SiO ₂ 32%). Warm each of the above solutions to 50℃,
They are simultaneously added to a separately prepared container and stirred to react. Reactants A and B were placed in separate pressure vessels and mixed, then heated to 130°C and subsequently stirred for 6 hours. The reaction solution was filtered through a Buchner funnel, and the cake was washed with 3 portions of pure water. The washed cake was then dried at 130° C. for 16 hours and ground in a sample mill to obtain a pigment having the following compositional formula. BaO・0.30P ₂ O ₅・0.38B ₂ O ₃・0.21SiO ₂・0.59H ₂ O The composition of this pigment is shown in Table 1, and the corrosion resistance test results are shown in Tables 2 to 6. Example 4 Prepare 750g of barium sulfide solution (BaS12%). 77g of trisodium phosphate (12 hydrate) and 173g of water
dissolve in Dissolve 44g of borax (decahydrate salt) in 206g of water. Warm each of the above solutions to 50℃,
These are simultaneously added to a separately prepared pressure vessel while stirring and reacting. Then, the temperature was raised to 130℃,
The mixture was subsequently stirred for 6 hours. The reaction solution was filtered through a Buchner funnel, and the cake was washed with 3 portions of pure water.
The washed cake was then dried at 130° C. for 16 hours and ground in a sample mill to obtain a pigment having the following compositional formula. BaO・_0.33P2O5・_0.41B2O3・_0.80H2O The composition of this pigment _is shown in Table ₁ , and the anticorrosion test results are shown in Tables 2 to 6.

【table】 Corrosion resistance test (A) Water-soluble melamine/alkyd resin paint (1) Paint composition

【table】

[Table] (2) Preparation of test plate Substrate: Bonderite #144 treated mild steel plate Baking: 60℃ x 20' then 140℃ x 30' Film thickness: 20 to 23μ (1-Coat) (3) Test results Table 2 show. Evaluation symbols in the same table and 3 to 6 are based on the following criteria. ◎ Extremely good 〇 Good ○△ Fairly good △ Bad × Extremely bad

【table】 (B) Water-dispersed epoxy modified resin paint (1) Paint composition

【table】

[Table] * Manufactured by Nippon Shokubai Chemical Co., Ltd., water-dispersible epoxy modified resin, solid content 40%
(2) Preparation of test plate Substrate: Untreated polished mild steel plate Drying: 5 days at room temperature Film thickness: 51-55μ (2-Coat) (3) Test results

【table】 (C) Acrylic emulsion paint (1) Paint composition

【table】

[Table] * Manufactured by Rohm & Haas, acrylic emulsion, solid content 46%
(2) Preparation of test plate Substrate: Untreated polished mild steel plate Drying: 5 days at room temperature Film thickness: 58-62μ (2-Coat) (3) Test results

【table】 (D) Medium oil-based alkyd resin paint (1) Paint composition

【table】

【table】 (2) Preparation of test plate Substrate: Bonderite #144 treated mild steel plate Drying: 5 days at room temperature Film thickness: 31~33μ (1-Coat) (3) Test results

【table】 (E) Phenol-modified alkyd resin paint (1) Paint composition (a) Undercoat paint

【table】

【table】 (b) Top coat paint

【table】 (2) Preparation of test plate Substrate: Untreated polished mild steel plate Drying: Dry at room temperature for 2 days after applying the undercoat. Dry at room temperature for 5 days after applying the top coat. Film thickness: Undercoat film 32-35μ Top coat film 29~33μ (3) Test results

【table】 [Brief explanation of drawings]

Attached Figure 1 shows the corrosion resistance and water resistance of a water-soluble melamine/alkyd resin paint containing a mixture of the pigment of the present invention and a conventional pigment, and the B ₂ O ₃ /
This is a graph explaining the relationship between P ₂ O ₅ (y/x), where △▲ indicates corrosion resistance and 〇● indicates water resistance.

Claims (1)

[Claims] 1 A compound obtained by reacting one or more selected from Ca, Sr, and Ba compounds with a phosphoric acid compound and a boric acid compound, and whose composition is McO・xP ₂ O ₅・yB ₂ O ₃・nH ₂ O (here, Me indicates Ca, Sr, Ba, x, y,
n is each 1 mole of MeO, x is 0.1 to 0.9,
y is 0.1 to 0.9, n is 0 to 2), and y/x is 0.1 to 9. 2. It is obtained by reacting one or more selected from Ca, Sr, and Ba compounds with a phosphoric acid compound, a boric acid compound, and a silicate compound, and its composition is
MeO・xP ₂ O ₅・yB ₂ O ₃・zSiO ₂・nH ₂ O (here,
Me represents Ca, Sr, Ba, x, y, z, n are each relative to 1 mole of MeO, x is 0.1 to 0.9, and y is
0.1 to 0.9, z is 0.8 or less, and n is 0 to 2), and y/x is 0.1 to 9.