JP2003041285A - Water-soluble cutting and grinding oil for aluminum or its alloy - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-soluble cutting and grinding oil which effectively can prevent the discoloration of aluminum or its alloy when subjected to cutting and grinding processing or in the period of standing after its processing. SOLUTION: The water-soluble cutting and grinding oil for aluminum or its alloy comprises 0.1-10 wt.% dibasic acid to be represented by the formula: HOOC-A-COOH (wherein A is an alkylene group having a 13-25C main chain), 0-80 wt.% mineral oil and/or fats and oils, an alkali metal compound and/or an amine in at least an equivalent amount based on the carboxyl group of the dibasic acid, and 0-50 wt.% surface active agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-soluble cutting and grinding fluid for aluminum or its alloys, and more particularly to water-soluble cutting for effectively preventing discoloration during cutting and grinding of the metal or during the standing period after the grinding. Regarding grinding fluid.

[0002]

[Prior art]

Aluminum and its alloys, which are amphoteric metals, are used for various purposes (for example, mechanical parts, electronic material parts, cans, sashes, etc.), but they have the drawback of being susceptible to corrosion by acids and alkalis. In particular, aluminum alloys that are more widely used than pure aluminum (for example, aluminum alloys containing metals such as copper and zinc) are more susceptible to corrosion and are more likely to blacken under alkaline conditions.

In order to deal with such a problem, various anticorrosive agents, such as pH, which have little influence on metal materials of this kind, and which do not cause discoloration or cause relatively little discoloration, are conventionally used. Nearly neutral region (7.5-
The anticorrosion agent adjusted to 8.5), the anticorrosion agent containing an inorganic salt such as sodium metasilicate, the anticorrosion agent containing a phosphorus compound, and the like are provided on the market. However, a neutral anticorrosive agent reduces rust resistance, antiseptic property, etc., and in the case of an inorganic salt-containing anticorrosive agent, the storage stability of the stock solution is very poor, resulting in gelation of the stock solution and precipitation of inorganic salts. In addition, the phosphorus-containing anticorrosive agent causes problems such as spoilage of the processing liquid and environmental pollution.

Various other anticorrosive agents have been proposed as anticorrosive agents for aluminum and its alloys. For example, JP-A-55-89478 discloses that an alkylenebiscarboxylic acid represented by the general formula: HOOC (CH ₂ ) nCOOH (wherein n represents an integer of 6 to 26) and a polymer compound are specified. A technique for preventing corrosion of metal in water using an alkaline aqueous solution or an alkaline alcoholic aqueous solution contained in a proportion is disclosed,
When this technique is applied to prevent discoloration of the metal, which is a problem associated with the processing of aluminum or its alloys, there arises a problem that the polymer compound adversely affects the processing of the metal.

Japanese Unexamined Patent Publication (Kokai) No. 2-182782 discloses a technique of using a mixture of dicarboxylic acid having 7 to 14 carbon atoms or a salt thereof as a corrosion inhibitor. Even when applied to aluminum or its alloys, discoloration of the metal over time cannot be effectively prevented.

Further, Japanese Patent Laid-Open No. 2000-129283 discloses a technique for solving the drawback of the water-soluble anticorrosive agent, which mainly impairs the properties of the lubricating oil, by using a poorly water-soluble organic acid salt. This type of poorly water-soluble anticorrosive component is unsuitable as a general discoloration preventing component of a water-soluble cutting and grinding fluid for aluminum or its alloys.

[0008]

DISCLOSURE OF THE INVENTION The present invention provides a water-soluble cutting and grinding oil agent which can effectively prevent discoloration of aluminum or its alloy during cutting and grinding or during the standing period after the cutting. It was done by.

[0009]

[Means for Solving the Problems] That is, the present invention relates to a water-soluble cutting and grinding fluid for aluminum or its alloys containing the following components (i) to (iv): (i) General formula (I): HOOC- 0.1 to 10% by weight of dibasic acid represented by A-COOH (I) (wherein A represents an alkylene group having a main chain of 13 to 25 carbon atoms), (ii) mineral oil and / Or 0 to 80% by weight of fats and oils,
(Iii) An equivalent amount or more of an alkali metal compound and / or amine with respect to the carboxyl group of the dibasic acid, and (iv) 0 to 50% by weight of a surfactant.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the general formula (I), A represents an alkylene group having a main chain of 13 to 25 carbon atoms, preferably 15 to 22 carbon atoms. The alkylene group may have an unsaturated bond and / or a branched chain. The number of carbon atoms in the branched chain is usually 10 or less, preferably 5 or less.

The compounds suitable as the dibasic acid represented by the general formula (I) are exemplified below.

[Chemical 1]

In the general formula (I), when the number of carbon atoms in the main chain of the alkylene group is less than 13, a corrosive effect is brought about rather than a discoloration preventing effect, and the number of carbon atoms is less than 25. If it is too large, not only the effect of preventing discoloration is not further improved, but also the solubility of the salt is lowered and it becomes difficult to obtain a uniform aqueous solution. If desired, two or more dibasic acids may be used in combination.

The content of the dibasic acid represented by the general formula (I) is 0.1 to 10% by weight, preferably 0.3 to 5% by weight, and the content is more than 0.1% by weight. If it is too small, sufficient corrosion resistance to aluminum or its alloy cannot be obtained, and even if the content is more than 10% by weight, the corrosion prevention effect is not increased and it is wasteful.

The water-soluble cutting and grinding fluid according to the present invention contains mineral oil and / or fat. Examples of fats and oils include vegetable oils (eg, castor oil, rapeseed oil, palm oil, soybean oil, olive oil, etc.), animal oils (eg, beef tallow, sheep oil, pork oil, etc.), and synthetic oils (eg, alkyl ester of pentaerythritol, tritium oil). Examples thereof include alkyl ester fatty acid alkyl ester of methylol propane), and vegetable oils and animal oils are particularly preferable. Mineral oil and /
Alternatively, two or more kinds of fats and oils may be appropriately used in combination, if desired.

The content of mineral oil and / or fat is generally 0 to 80% by weight, but it depends on the type of cutting and grinding fluid. For example, in the case of the emulsion type, it is 40 to 80% by weight, in the case of the solve type, it is 0 to 40% by weight, and particularly in the case of the oil-containing solvel type, it is 10 to 40% by weight. %, Preferably 1
It is 5 to 35% by weight. When the content of the mineral oil and / or the oil / fat is more than 80% by weight, it becomes difficult to dilute the water-soluble cutting and grinding fluid finally obtained with water.

The water-soluble cutting and grinding fluid according to the present invention contains an alkali metal compound and / or an amine. Examples of alkali metal compounds include alkali metal hydroxides and alkali metal carbonates, with sodium or potassium hydroxide being particularly preferred. Suitable amines include alkylamines having 1 to 5 carbon atoms (eg, ethylamine, propylamine, etc.), alkanolamines (eg, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine). , Triisopropanolamine, etc.), morpholine, cycloalkylamine (eg, cyclohexylamine, etc.), 3,3-dimethylpropanediamine, etc., but water-soluble amines are particularly preferable. Among the water-soluble amines, oxygen-containing amines such as the above-mentioned alkanolamines and morpholine are particularly preferable from the following viewpoint. That is, this type of oxygen-containing amine not only effectively neutralizes the above dibasic acid and improves the antiseptic property of the working fluid and the anticorrosive property of the related machines and devices, but also the anionic surfactant. It functions as a suitable counter ion and contributes to the stabilization of the surfactant-containing stock solution and the diluted use solution. The alkali metal compound and / or amine may be appropriately used in combination, if desired.

The content of the alkali metal compound and / or the amine is 1 to 50% by weight, preferably 5 to 40% by weight, and when the content is less than 1% by weight, the dibasic acid is sufficiently contained. Not only the neutralization is impossible, but also the antiseptic property of the working fluid and the rust preventive property of the related machines and devices are reduced, and even if the content is more than 50% by weight, Not only the improvement of the effect concerning neutralization, antiseptic property and rust preventive property is not observed, but also the problem of work hygiene (for example, irritation of respiratory system, rough skin, etc.) is brought about.

The water-soluble cutting and grinding fluid according to the present invention further contains a surfactant. As the surfactant, any of a cationic surfactant, an anionic surfactant and a nonionic surfactant may be used, but an anionic surfactant and / or a nonionic surfactant are preferred. Examples of suitable anionic surfactants include alkyl group-containing sulfonates, alkyl group-containing sulfonates, alkyl group-containing phosphates, alkyl group-containing phosphates, organic fatty acids and organic fatty acid derivatives. Group-containing sulfonates, organic fatty acids and organic fatty acid derivatives are particularly preferred. Further, a suitable nonionic surfactant is an alkyl alcohol-ethylene oxide adduct,
Examples thereof include terminal alkyl ethers of alkyl alcohol-ethylene oxide adducts, organic fatty acid-ethylene oxide adducts, hydroxy fatty acid-ethylene oxide adducts, pluronic surfactants, tetronic surfactants and sugar ester-ethylene oxide adducts. The surfactants may be used in combination of two or more kinds, if desired.

The content of the surfactant is generally 1 to 50.
The amount is preferably wt%, preferably 5 to 40 wt%, but varies depending on the type of cutting and grinding fluid and the purpose of use. For example, in the case of an emulsion type or an oil-containing solvel type used for emulsification or lubrication purposes, the content is 10 to 30% by weight, and in the case of a soluble type used for lubrication purposes, Has a content of 10 to 40% by weight. When the content of the surfactant is less than 1% by weight, the initial object of the present invention cannot be achieved, and even when the content is more than 50% by weight, the effect of adding the surfactant is not achieved. Not only is there no improvement, but problems such as foaming of cutting and grinding fluid occur.

If desired, a lubricant, a defoaming agent, an extreme pressure additive, a preservative and the like may be appropriately added to the water-soluble cutting and grinding fluid according to the present invention.

The above-mentioned water-soluble cutting and grinding fluid for aluminum or its alloys according to the present invention is usually diluted with water 5 to 100 times before use.

[0022]

Example 1 Test liquid 1 was prepared by diluting the working liquid obtained by the formulation shown in Table 1 by 10 times (weight ratio) with tap water. A test piece plate (20 mm × 70 mm) of aluminum alloy (ADC-12) was polished with # 240 water-resistant sandpaper and then degreased with acetone.
When this test piece plate was left half-immersed in the test liquid 1 at room temperature, and after 24 hours, the discolored state of the test piece plate was observed, no discoloration was observed in the immersed part and the boundary part with the test liquid. It was

Examples 2 to 63 In accordance with the procedure of Example 1, discoloration between the immersed portion and the boundary portion of the test piece plate semi-immersed in the test liquids 2 to 63 prepared by the formulation shown in Tables 1 to 9 The condition is observed and the result is shown in Table 1.
~ Shown in Table 9. The evaluation symbols “◎”, “○”, “Δ” and “x” in Tables 1 to 9 for discoloration prevention property are “no discoloration”, “slight discoloration”, “gray discoloration” and “black discoloration”, respectively. Means

Comparative Examples 1 to 29 Based on the procedure of Example 1, the dipping portion and the boundary portion of the test piece plate semi-dipped in the test liquids 1'to 29 'prepared according to the formulation shown in Tables 1 to 9 were prepared. Was observed, and the results are shown in Tables 1 to 9.

[0025]

[Table 1]

[0026]

[Table 2]

[0027]

[Table 3]

[0028]

[Table 4]

[0029]

[Table 5]

[0030]

[Table 6]

[0031]

[Table 7]

[0032]

[Table 8]

[0033]

[Table 9]

The dibasic acid components A to K contained in the test solutions shown in Tables 1 to 9 are as follows:

[Chemical 2]

[0035]

By using the water-soluble cutting and grinding oil agent according to the present invention, it is possible to effectively prevent discoloration of aluminum or its alloy during cutting and grinding and during the standing period after the processing.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C10M 133/08 C10M 133/08 // C10N 10:02 C10N 10:02 20:00 20:00 Z 30: 12 30:12 40:22 40:22 F term (reference) 4H104 AA13C BB18C BE04C DA02A DA06A EA17Z EB02 FA01 LA06 PA22 PA33

Claims (5)

[Claims] 1. A water-soluble cutting and grinding fluid for aluminum or its alloys, which contains the following components (i) to (iv): (i) General formula (I): HOOC-A-COOH (I) (wherein A Represents an alkylene group having a main chain of 13 to 25 carbon atoms) 0.1 to 10% by weight of dibasic acid, (ii) 0 to 80% by weight of mineral oil and / or fat and oil,
(Iii) An equivalent amount or more of an alkali metal compound and / or amine with respect to the carboxyl group of the dibasic acid, and (iv) 0 to 50% by weight of a surfactant. 2. The water-soluble cutting and grinding fluid according to claim 1, wherein the oil or fat is a vegetable oil and / or a synthetic oil. 3. The water-soluble cutting and grinding fluid according to claim 1, wherein the amine is a water-soluble oxygen-containing amine. 4. The water-soluble cutting and grinding oil agent according to claim 1, wherein the surfactant is an anionic surfactant and / or a nonionic surfactant. 5. A dibasic acid and an alkali metal compound and / or
Alternatively, the water-soluble cutting and grinding oil agent according to any one of claims 1 to 4, wherein the molar ratio with the amine is 1: 2 to 1:20.