JP3162806B2 - Rust prevention 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 for use on an active new surface generated by cutting metal, and more particularly to a rust preventive suitable for preventing cut edges of a crown used for food containers.

[0002]

2. Description of the Related Art Since a crown is manufactured by stamping a thin metal plate such as printed tin-free steel, its periphery, that is, a cut edge portion, is a very active new surface generated by cutting metal. On the other hand, if there is a place to be an anode and a place to be a cathode on the metal surface due to non-uniformity such as impurities, oxide film defects, metal crystal structure, and rolling, a local battery is quickly formed. For this reason, moisture attached to the cut edge portion of the crown, oxygen in the atmosphere, etc., easily form a local battery, and the electrochemical reaction proceeds, so-called wet corrosion occurs, and the crown is cut from the cut edge portion. The problem of rusting arises. In order to prevent the rust of the wet corrosion of the crown cut edge portion, a method such as passivation of the metal surface such as chromate conversion treatment, application of a paint containing a rust preventive pigment, and application of a rust preventive oil or the like. There is. However, passivation of metal surfaces is not suitable for crowns due to toxicity and complicated processing steps, and the application of paint containing rust-preventive pigments requires the use of lead red, lead suboxide, cyanamide lead, and basic chromic acid. Many rust preventive pigments such as lead, zinc molybdate and barium meta (borate) are toxic. If a coating containing a rust preventive pigment is applied to the cut edge, it will come off as dust during hoppering, especially when plugging. However, it is not preferable because contents such as bottles using a crown may be contaminated. In addition, application of rust prevention oil, etc.
Although a very small amount can exhibit a certain level of rust prevention and does not fall off by popping or tapping, the oil film has a low adsorbing power to the metal surface and has a drawback that it easily falls off during the sterilization process. Further, a stainless steel crown which does not generate rust can be used, but there is a disadvantage that the cost is increased. As a result of examining various methods as described above, it has been found that the coating agent used for the rust prevention treatment of the crown cut edge portion needs to satisfy the following conditions.

[0003] The application method is simple and quick-drying, and there is no stickiness to prevent troubles on the production line. There is little odor at the time of work, and after the drying, no unpleasant odor remains on the crown cap. There is no problem in food hygiene. Do not fall off as dust at the time of hopper ringing or tapping. After tapping, paste tool treatment using hot water of about 70 ° C does not drop off and can maintain rust prevention. Inexpensive application to the cut edge portion (no problem in appearance). Prevention of water and O ₂ ingress with a small amount of application Considering the above conditions, prevention of the cut edge of the crown It is clear that conventional rust preventive methods such as general rust preventive paints and electrodeposition paints cannot be used for rust.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides a rust preventive agent which satisfies the above-mentioned conditions and which is used for an active new surface generated by cutting metal, and which is particularly suitable for preventing rust on a cut edge portion of a crown used for food containers. It is intended to provide an agent.

[0005]

In order to solve the above-mentioned problems, the present invention comprises a compound of the following formula 1, that is, a copolymer of ethylamine or N- (β-aminoethyl) ethylamine-modified siloxane and dimethylsiloxane. It provides anticorrosive _{composition: Si (CH 3) (R} ) 2 -O- [Si (CH 3) 2 -O
_{-] m - [Si (CH} 3) (CH 2 -R'-NH 2)
O] _n -Si (CH ₃ ) (R) ₂ ... [I] (wherein, R is —CH ₃ or —OCH ₃ ; R ′ is —CH ₂
-CH ₂ - or _{-CH 2 -CH 2 -NH-CH 2} -CH
_2- ; m is 10 to 70; n is 1 to 10. ). Further, the invention provides compounds of the following formula II, i.e. to provide a rustproofing composition comprising a condensate of sarcosinates and (methylamino acid) and fatty acids such as oleic acid: R-CO-N (CH 3) - CH ₂ COOH
[II] (wherein, R is a saturated or unsaturated alkyl group having 11 to 17 carbon atoms).

Further, the present invention relates to a compound of the following formula III, that is, a copolymer of dimethylsiloxane alone or a substituted siloxane (having a viscosity of 10
0 ~10,000cst) provides rustproofing composition _{comprising: Si (CH 3) 3 -O-} [Si (CH 3) RO-] n Si (CH 3) 3 [III] ( wherein, R - H or —CH ₃ ; n is 1 to 8.).

When the compound of the formula III is used together with the compound of the formula 1 or II, the ratio of the compound is [I] / [III] = 100/0 to 10/90 by weight, preferably 95/5. ＩＩ50 / 50, [II] / [I
II] = 100/0 to 90/10, preferably 100 /
0 to 95/5. Commercially available products that can be used as compounds of Formula I of the present invention include SF8417 from Tore Dow Corning Silicone Co., Ltd., TSF4702, TSF4703 and TSF4706 from Toshiba Silicone Co., Ltd.
And Shin-Etsu Chemical's KF393 and KF85
7, KF862, has KF864 and KF865, to what can be mentioned as compounds of formula II of the present invention, oleoyl sarcosinate _{(CH 3 (CH 2) 7} -C
_{H = CH (CH 2) 7} -CO-N (CH 3) -CH 2 C
OOH). Commercial products that can be used as the compound of the formula III of the present invention include TOSHIBA SILICON CO., LTD.
SF451 series (10-100,000 cps) and KF-96, KF96H (1
0 to 1,000,000 cps). When these compounds are used as a rust preventive, they are added to hydrocarbon solvents such as toluene, xylene, and mineral spirits.
It is used after being diluted to -20% by weight, preferably 10-15% by weight. In the present invention, as a method of applying a rust preventive agent to the crown cut edge portion, in a device for pressing a gasket such as polyethylene on the crown, impregnating the belt or the like with a rust preventive agent, the crown cut edge portion. Or a method in which a rust preventive impregnated in a belt or the like in a post-process of the gasket pressing device is applied to the crown cut edge portion.

[0008]

[Example 2]

A rust preventive was produced and tested in the same manner as in Example 1 except that Shin-Etsu Chemical KF862 was used as the compound for the rust preventive. Example 3 A rust preventive was produced in the same manner as in Example 1, except that oleoyl sarcosine was used as a compound for the rust preventive.
And a test was performed.

[Comparative Example 1] Various tests were performed using the crown of Example 1 which had not been subjected to the rust-proof treatment. High-temperature and high-humidity test (40 ° C. × 90% RH + spray of artificial rainwater) As test samples, an unplugged crown and a capped crown were used. 40 rpm x 15 min hopper ring (100 pcs)
Was done. The hot water shower treatment was performed as follows.
(Conditions for past riser) 50 ° C x 15 minutes + 70 ° C x 1
0 minutes + 50 ° C × 20 minutes 40 environmental test rooms (10 m ² )
C. and 90% RH, and artificial rainwater was sprayed once or twice daily to accelerate the generation of rust, and the time-dependent change was observed. Rust evaluation method Considering the degree of rust generated on 21 folds,
It was evaluated with a score of up to 21 levels. 0: No rust at all ~ 21: All rusted These numerical values were treated as measured values. The test was performed on 10 crowns, and the average value was obtained. Observation was made 2 and 7 days after the start of the experiment.

Salt spray test (5% NaCl, 35 ° C.) An unplugged crown was used as a test sample. Hopper ring. Same as hot and humid test. Hot water shower treatment. Same as hot and humid test. Using a salt spray tester, the test was performed under the conditions of 5% NaCl and 35 ° C. Rust evaluation method. Same as hot and humid test. Observation was made 24 hours after the start of the experiment. Petri dish method An unplugged crown was used as a test sample. Hopper ring. Same as hot and humid test. Hot water shower treatment. Same as hot and humid test. Put two pieces of filter paper on a Petri dish of 90mmφ, 3.5g of distilled water
, And the four treated crowns were placed face down and sealed. The petri dish was held horizontally in a 40 ° C. constant temperature bath and kept for 24 hours. The filter paper was dried and rust was observed. Rust evaluation method. Same as hot and humid test.

[0011]

[Table 1] [Test results] Table 1 40 ° C, 90% RH hot and humid test + artificial rainwater for stopper cap Rust prevention liquid Example 1 Example 2 Example 3 No application 塗布─ Past riser No Yes No Yes No No No (Hot water shower treatment) ─────────────────────────────────── ─ After 2 days 0.2 1.1 0.4 3.2 0.4 5.7 7.5 後 After 7 days 0.9 2.7 1.0 4.8 1.3 9.4 10.3 ────────────────────────────────────

[0012] 40 ° C, 90% RH high temperature and high humidity test for unplugged crown + artificial rainwater Rust prevention liquid Example 1 Example 2 Example 3 No application 塗布 Paste riser No Yes No Yes No Yes No (Hot water shower treatment) ──────────────────────────────────── After 2 days 0.7 4.2 1.0 6.0 1.3 7.0 8.3 ──────────────────────────────────── 7 days later 1.7 8.4 4.1 10.9 3.7 15.0 16.8 ─ ───────────────────────────────────

Salt spray test on unplugged crown 5% NaCl, 35 ° C., after 24 hours Rust prevention liquid Example 1 Example 2 Example 3 No application 塗布─────── Past riser No Yes No Yes No No No (Hot water shower treatment) ───────────────────────────── ─────── After 24 hours 1.9 2.2 2.4 4.5 4.0 7.5 11.0 ───────────────────────────────── ───

Petri dish method for unplugged crown at 40 ° C., after 24 hours Rust prevention liquid Example 1 Example 2 Example 3 No application 塗布── Past riser No Yes No Yes No No No (Hot water shower treatment) ────────────────────────────────── ── After 24 hours 0.5 3.5 0.9 4.4 1.0 7.7 8.2 ────────────────────────────────────

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Sadahito Michishita 1043, Kamiyori, Atogi-shi, Kanagawa Prefecture, Japan Daito-Paint Co., Ltd. (72) Inventor Masaaki Niisato 1043, Kamiyori, Atsugi-shi, Kanagawa Prefecture, Japan (56) reference Patent flat 4-221085 (JP, a) JP flat 2-8382 (JP, a) JP Akira 60-15469 (JP, a) (58 ) investigated the field (Int.Cl. ⁷ , DB name) C23F 11/00-11/18

Claims (2)

(57) [Claims] A rust preventive composition comprising a compound of the following formula I or II: Si (CH ₃ ) (R) ₂ -O- [Si (CH ₃ ) ₂ -O-] _m- [Si (CH _{3 ) (CH 2 -R'-NH 2} ) O] n -Si (CH 3) (R) 2 [I] ( wherein, R is -CH ₃ or -OCH _3; R 'is -CH ₂ -CH ₂ -Or
_{-CH 2 -CH 2 -NH-CH 2} -CH 2 -; m is 10 to 70; n is from 1 to 10. ); R-CO-N ( CH 3) -CH 2 COOH [II] ( wherein, R represents a saturated or unsaturated alkyl group having 11 to 17 carbon atoms).. 2. The rust-preventive composition according to claim 1, comprising a compound of the formula III: Si (CH ₃ ) ₃ -O- [Si (CH ₃ ) RO-] _n Si (CH ₃ ) ₃ [III] (wherein, R is -H or -CH _3; n is 1-8.).