JP3300936B2 - Rust prevention coating composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rust preventive coating composition, and more particularly, to a rust preventive coating composition containing a slag containing an alkali group produced in a refining process and a resin.

[0002]

BACKGROUND OF THE INVENTION Problems to be solved by the invention are described in "Encyclopedia of rust prevention" (published by the Industrial Research Institute Co., Ltd.), "Rust prevention and anticorrosion coating technology" (Kogaku Tosho Co., Ltd.), etc. As such, lead-based pigments such as lead suboxide, lead tin, lead cyanamide or zinc chromate, chromium pigments such as strontium chromate are used as rust preventive pigments for paints,
Lead, hexavalent chromium, and the like have hygiene problems and need to be converted to safer materials in terms of health effects on the human body, environmental pollution, and disposal of industrial waste.

[0003] On the other hand, rust-preventive pigments containing no heavy metals and having higher hygiene properties have been studied. However, in many cases, the rust-preventive effect has not been sufficiently obtained. Difficult to use economically.

[0004] On the other hand, slag discharged from a blast furnace at the time of steel production is used in various ways such as slag cement. However, since the amount of discharge is enormous, it has to be disposed of as industrial waste.

Accordingly, an object of the present invention is to provide a rust preventive coating composition which is effective as a long-term rust preventive and protective coating.

Another object of the present invention is to provide a rust-preventive coating composition which prevents the invasion of an acidic substance to the iron surface through a coating film by acid rain or the like by neutralizing slag.

Still another object of the present invention is to provide a rust preventive coating composition that can utilize slag as an inexpensive rust preventive pigment.

[0008]

As one of the methods for preventing rust of iron, there is known a method in which the surface of iron is kept alkaline and passivated. It is generally said that iron has a stable state in which a passivation layer of iron (II) hydroxide is formed in a pH range of 9 to 12.5.

The present inventors have conducted intensive studies based on these findings and have obtained the following findings. PH 10 when slag is in water
~ 12.6, and solidification with an epoxy resin or an epoxy polyol resin suppresses the elution of alkali components of slag (main component: 20 to 75% of calcium oxide, 1 to 20% of magnesium oxide) into water, It keeps the surface alkaline for a long period of time and exhibits a rust-preventive effect. Neutralizes acidic substances that enter from the coating surface, such as acid rain, and prevents the promotion of corrosion by acids. When the ratio of slag to resin solids is 0.88 using solid epoxy resin, the pH of the coating film is 10.
It is 10.9 in 7, 30 days.

The pH of the slag can be measured with a glass electrode pH meter 24 hours after adding 100 g of the slag to 900 ml of on-exchanged water at 20 ° C. and stirring. For the pH of the coating using slag, isolate the coating, take 50 g into a 450 ml wide-mouthed glass bottle, add 150 ml of ion-exchanged water, seal tightly, leave at 40 ° C, separate the water, and measure with a glass electrode pH meter. it can.

That is, according to the present invention, an average molecular weight of 300 to 3000 and an epoxy equivalent of 180 to 220 are used.
For a total of 100 parts by weight of the epoxy resin and the curing agent of 0,
1 slag containing alkali groups generated in the refining process
It is a rust-preventive coating composition characterized by being mixed with 0 to 300 parts by weight.

If the amount of slag is less than 10 parts by weight based on 100 parts by weight of the resin solid content, the alkali component is small and the iron surface cannot be kept alkaline, so that the rust preventing effect cannot be exhibited. On the other hand, if it exceeds 300 parts by weight, the coating film becomes coarse and the moisture permeation increases, and the alkali component is rapidly eluted, so that the effect is not maintained and rust is easily generated.

The epoxy resin has a molecular weight of 300 to 30.
Those having an epoxy equivalent of 00 and an epoxy equivalent of 180 to 2200 are preferred. If the molecular weight is less than 300 or the epoxy equivalent is less than 180, the cured film will have insufficient mechanical strength, water resistance, corrosion resistance, etc., and will have a molecular weight of 3000.
Or, when the epoxy equivalent exceeds 2200, it becomes difficult to dissolve in a solvent and the solid content of the coating material is reduced, so that a thick coating in heavy corrosion protection becomes difficult.

As the epoxy resin, bisphenol A glycidyl ether type epoxy resin is preferable. Various modified epoxy resins having low molecular weight, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, aliphatic epoxy resin, glycidyl ether type resin, One type or a mixture of two or more types of novolak type epoxy resins may be used. Further, a polyol of the above epoxy resin may be used.

In addition, bisphenol A glycidyl ether type epoxy resin may be one or two resins such as petroleum resin, xylene resin, alicyclic oligomer resin, chroman resin, indene resin, polybutadiene resin, acrylic resin, alkyd resin and phenol resin. You may mix and use more than one kind.

Examples of the curing agent for the epoxy resin include a polyamide-based curing agent , an aliphatic or aromatic polyamine-based curing agent, a ketimine-based curing agent, and a mercaptan-based curing agent. Further, as a curing agent for the epoxy resin polyol , toluene diisocyanate, xylene diisocyanate,
Diisocyanate-based curing agents such as MDI and isophorone diisocyanate;

As slag, blast furnace slag, granulated slag,
There is converter slag, etc., and the particle size is 75μ or less 90%
It is preferable that it is above.

Next, the rust-preventive coating composition of the present invention contains, as coloring pigments, inorganic pigments such as titanium dioxide, carbon black, graphite, flaky iron oxide, iron oxide, and chromium oxide; and aluminum, copper, and stainless steel. Metal powder, glass flake, phthalocyanine, azo,
Organic pigments such as quinacridone can be used.

The rust-preventive coating composition of the present invention contains, as rust-preventive pigments, lead suboxide, leadtan, cyanamide lead, lead sulfate, calcium leadate, zinc chromate, strontium chromate, zinc phosphate, zinc molybdate, phosphorus Zinc molybdate, aluminum phosphate and the like can be used in combination.

In the rust preventive coating composition of the present invention, calcium carbonate, talc, kaolin, barium sulfate, precipitated barium sulfate, colloidal silica, mica and the like can be used as extenders.

In the rust-preventing coating composition of the present invention, epoxidized soybean oil, chlorinated paraffin, phthalic ester type, ether type or the like can be used as a plasticizer.

The rust-preventive coating composition of the present invention comprises a surface conditioner, a dispersant, an anti-separation agent, an anti-settling agent, an anti-sagging agent,
Paint additives such as defoamers can be used.

The rust preventive coating composition of the present invention contains toluene, xylene, medium to high boiling aromatic hydrocarbon solvents, aliphatic hydrocarbon solvents, alcohol solvents, ketone solvents, ester solvents as organic solvents. And glycol ether solvents.

【Example】

Hereinafter, the present invention will be described with reference to examples.

Example 1 A 70% xylene solution of an epoxy resin having an epoxy equivalent of 450 to 500 (Epicoat # 1001, Yuka Shell Co., Ltd.)
22 parts by weight, 63 parts by weight of slag, 5 parts by weight of titanium dioxide, 6 parts by weight of xylene, and 4 parts by weight of isobutanol were added to make a total of 100 parts by weight, and dispersed by a glass bead paint shaker for 60 minutes.

13.9 parts by weight of a polyamidoamine-based curing agent (ADEKA HARDNER-EH-306, solid content 70%, manufactured by Asahi Denka Co., Ltd.) was added to 100 parts by weight of this dispersion, and a special thinning liquid (xylene ratio by weight) / Isobutanol / MIB
K = 60/20/20) 10 parts by weight and degreased with xylene (JIS G 3141 SPCC-SD, size 0.8 × 70 ×
(150mm) and brushed to a film thickness of 70 ± 5μ at 20 ℃
For 10 days.

At this time, the weight ratio of the slag to the resin solid content is 0.41.

Example 2 A 70% xylene solution of an epoxy resin having an epoxy equivalent of 450 to 500 (Epicoat # 1001, Yuka Shell Co., Ltd.)
48 parts by weight), 36 parts by weight of slag, 5 parts by weight of titanium dioxide, 6 parts by weight of xylene, and 5 parts by weight of isobutanol were added to make a total of 100 parts by weight and dispersed by a glass bead paint shaker for 60 minutes.

10.6 parts by weight of a polyamidoamine-based curing agent (ADEKA HARDNER-EH-306, solid content: 70%, manufactured by Asahi Denka Co., Ltd.) was added to 100 parts by weight of this dispersion, and a special thinning liquid (xylene ratio by weight) / Isobutanol / MIB
K = 60/20/20) 10 parts by weight and degreased with xylene (JIS G 3141 SPCC-SD, size 0.8 × 70 ×
(150mm) and brushed to a film thickness of 70 ± 5μ at 20 ℃
For 10 days.

At this time, the weight ratio of the slag to the resin solid content is 0.88.

Example 3 A 70% xylene solution of an epoxy resin having an epoxy equivalent of 450 to 500 (Epicoat # 1001, Yuka Shell Co., Ltd.)
32.8 parts by weight), 51 parts by weight of slag, 5 parts by weight of titanium dioxide, 6 parts by weight of xylene, and 5.2 parts by weight of isobutanol were added to make a total of 100 parts by weight, and dispersed by a glass bead paint shaker for 60 minutes.

To 100 parts by weight of this dispersion, 7.4 parts by weight of a polyamidoamine-based curing agent (ADEKA HARDNER-EH-306, solid content: 70%, manufactured by Asahi Denka Co., Ltd.) and a special thinning liquid (xylene ratio by weight) / Isobutanol / MIBK
= 60/20/20) and soft iron plate (JIS G 3141 SPCC-SD, size 0.8 x 70 x 15) degreased with xylene
0 mm) and dried at 20 ° C. for 10 days.

At this time, the weight ratio of the slag to the resin solid content is 1.81.

Example 4 A 70% xylene solution of an epoxy resin having an epoxy equivalent of 450 to 500 (Epicoat # 1001, Yuka Shell Co., Ltd.)
40.6 parts by weight of xylene resin (Nicanol LL,
8.6 parts by weight of Nippon Yupica Co., Ltd., 8.6 parts by weight of slag, 5 parts by weight of titanium dioxide, 4 parts by weight of xylene, and 3.8 parts by weight of isobutanol were added to make a total of 100 parts by weight, and the mixture was mixed with a glass bead paint shaker for 60 minutes. Dispersed.

With 100 parts by weight of this dispersion, 7.2 parts by weight of a polyamidoamine-based curing agent (ADEKA HARDNER-EH-306, solid content: 70%, manufactured by Asahi Denka Co., Ltd.) and a special thinning liquid (xylene ratio by weight) / Isobutanol / MIBK
= 60/20/20) and 10 parts by weight of defatted soft iron plate (JIS G 3141 SPCC-SD, size 0.8 x 70 x 15)
0 mm) and dried at 20 ° C. for 10 days.

At this time, the weight ratio of the slag to the resin solid content is 0.90.

Comparative Example 1 A 70% xylene solution of an epoxy resin having an epoxy equivalent of 450 to 500 (Epicoat # 1001, Yuka Shell Co., Ltd.)
Talc S. to 48 parts by weight. S. S (Nihon Talc Co., Ltd.)
36 parts by weight, 5 parts by weight of titanium dioxide, 6 parts by weight of xylene and 5 parts by weight of isobutanol were added to make a total of 100 parts by weight, and dispersed by a glass bead paint shaker for 60 minutes.

With respect to 100 parts by weight of this dispersion, 10.6 parts by weight of a polyamidoamine-based curing agent (ADEKA HARDNER-EH-306, solid content 70%, manufactured by Asahi Denka Co., Ltd.) was used, and a special thinning liquid (weight ratio xylene) / Isobutanol / MIB
K = 60/20/20) 10 parts by weight and degreased with xylene (JIS G 3141 SPCC-SD, size 0.8 × 70 ×
(150mm) and brushed to a film thickness of 70 ± 5μ at 20 ℃
For 10 days.

At this time, the weight ratio of talc to resin solid content is 0.88.

Comparative Example 2 A 70% xylene solution of an epoxy resin having an epoxy equivalent of 450 to 500 (Epicoat # 1001, Yuka Shell Co., Ltd.)
48 parts by weight) 41 parts by weight of titanium dioxide, 6 parts of xylene
To 100 parts by weight, and dispersed by a glass bead paint shaker for 60 minutes.

With respect to 100 parts by weight of this dispersion, 10.6 parts by weight of a polyamidoamine-based curing agent (ADEKA HARDNER-EH-306, solid content 70%, manufactured by Asahi Denka Co., Ltd.) was used, and a special diluent (weight ratio xylene) / Isobutanol / MIB
K = 60/20/20) 10 parts by weight and degreased with xylene (JIS G 3141 SPCC-SD, size 0.8 × 70 ×
(150mm) and brushed to a film thickness of 70 ± 5μ at 20 ℃
For 10 days.

At this time, the weight ratio of titanium dioxide to resin solid content is 1.00.

Comparative Example 3 A 70% xylene solution of an epoxy resin having an epoxy equivalent of 450 to 500 (Epicoat # 1001, Yuka Shell Co., Ltd.)
Aluminum phosphate (K White, manufactured by Teica Co., Ltd.) 22 parts by weight, and talc S.P. S. S (manufactured by Nippon Talc), 14 parts by weight, 5 parts by weight of titanium dioxide, 6 parts by weight of xylene, and 5 parts by weight of isobutanol were added to give a total of 100 parts.
Parts by weight were dispersed with a glass bead paint shaker for 60 minutes.

With respect to 100 parts by weight of this dispersion, 10.6 parts by weight of a polyamidoamine-based curing agent (ADEKA HARDNER-EH-306, solid content 70%, manufactured by Asahi Denka Co., Ltd.) was used, and a special thinning liquid (xylene weight ratio) / Isobutanol / MIB
K = 60/20/20) 10 parts by weight and degreased with xylene (JIS G 3141 SPCC-SD, size 0.8 × 70 ×
(150mm) and brushed to a film thickness of 70 ± 5μ at 20 ℃
For 10 days.

At this time, the weight ratio of the total of aluminum phosphate and talc to the solid content of the resin was 0.88.

[0046]

[Table 1]

[0047]

According to the present invention, the alkali component in the slag gradually elutes from the coating over a long period of time to keep the iron surface alkaline and prevent rusting, and is effective as a long-term rust prevention and protective coating. .

Further, the penetration of the acidic substance into the iron surface through the coating film due to acid rain or the like can be prevented by the slag neutralizing action.

Further, the slag can be utilized not as industrial waste but as an inexpensive rust preventive pigment.

Continuing from the front page (72) Inventor Kazumi Daitoku 1-1, Hibata-cho, Tobata-ku, Kitakyushu-shi, Fukuoka Nippon Steel Corporation Inside Yawata Works (72) Inventor Yuzo Yugami 1043, Kamiyori, Atsugi-shi, Kanagawa Daito Inside Paint Co., Ltd. (72) Inventor Mikitomo Ikeda 5-6-64 Akasaka, Kokurakita-ku, Kitakyushu-shi, Fukuoka Prefecture Daiki Kogyo Co., Ltd. (56) References JP-A-60-137773 (JP, A) Showa 55-60057 (JP, A)

Claims (1)

(57) [Claims] 1. A slag containing an alkali group generated in a refining process is mixed in an amount of 10 to 300 parts by weight based on a total of 100 parts by weight of an epoxy resin having an average molecular weight of 300 to 3000 and an epoxy equivalent of 180 to 2200 and a curing agent. A rust preventive coating composition characterized by comprising: