JPH0218496A - Base for water-soluble metal processing oil - Google Patents

Abstract

PURPOSE:To obtain the title corrosion-resistant base agent having excellent lubrication performance and long-term stability, replaceable with a vegetable oil containing an ester compound such as trimellitic ester or phosphoric ester. CONSTITUTION:The aimed base consisting of one or more ester compounds selected from (A) an ester of trimellitic acid and 2-20C aliphatic (un)saturated alcohol, (B) an ester of phosphoric acid and 2-20C aliphatic (un)saturated alcohol whose halogen group may be replaced and (C) an ester of 2-20C aliphatic (un)saturated carboxylic acid and trimethylolpropane. The example of the base applied is a cutting oil, grinding oil, polishing oil, rolling oil, pressing oil, drawing oil, plastic working oil, drilling oil, wire drawing oil, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a water-soluble metalworking fluid base with excellent corrosion resistance.

[Prior Art and Problems] Water-soluble metal working fluids are metal processing fluids made by using naphthenic or paraffinic mineral oils, synthetic oils, or ester compounds as base oils and emulsifying or solubilizing them with appropriate surfactants. They are roughly divided into emulsion-type oils, which become cloudy when diluted with water, and soluble oils, which become transparent or translucent when diluted with water.

Depending on the purpose, such water-soluble metal working fluids may contain oiliness improvers such as polyolefin oils, vegetable oils, animal oils, higher fatty acids, higher alcohols, amines, metal soaps, etc.
Various additives such as a rust preventive agent, a preservative, a pH adjuster for rust prevention/preservation, an extreme pressure additive, an antioxidant, and an antifoaming agent are appropriately blended.

In recent years, there has been a desire to improve the workplace environment, prevent fires, promote rationalization to save resources and costs, and improve cooling performance to accommodate faster processing speeds. The superiority of metalworking fluids is beginning to be emphasized, and their usage is increasing.

However, water-soluble metalworking fluids generally tend to spoil when used for a long period of time, and as a result,
This can cause the generation of bad odors, a decrease in the performance of the oil, corrosion of machine tools and workpieces due to acidification of the oil, generation of rust, and clogging of pipes due to bacterial cells and extracellular substances. Furthermore,
Changes in the appearance of the oil agent (breakage of emulsion, separation of oil and water,
It may also cause the liquid to become cloudy, sticky substances to form, etc.).

This may be caused by microorganisms in the soil, air, diluted water, or other oils used together (e.g., hydraulic oil, lubricating oil, anti-rust oil).
This is caused by the contamination of microorganisms present in the oil, that is, bacteria such as aerobic bacteria, facultative anaerobic bacteria, and anaerobic bacteria such as sulfate-reducing bacteria, yeast, and filamentous fungi. These microorganisms proliferate particularly actively during hot and humid seasons or when machines are continuously stopped.

One possible way to solve this problem is to replace the oil in a short period of time, but this approach has the problems of time loss and increased costs due to replacement work, as well as increased expense for wastewater treatment.

Also, methods have been proposed in which a disinfectant, a preservative, an alkanolamine, a pH improver such as potassium hydroxide, sodium hydroxide, etc. are added. However, the addition of these drugs
New problems arise, such as the generation of chemical odors, decreased oil performance, increased toxicity, adverse effects on workers' skin, and reduced ease of treating wastewater.

Furthermore, methods for circulating oil even when the machine is stopped, and methods for forcibly aerating air and ozone (Japanese Patent Application Laid-Open No. 1983-1999-1) have been developed.
115697), a method of adding a substance having a preservative effect such as a metal carrier or a metal compound thereof (Japanese Patent Laid-Open No. 59-18
No. 7093, JP-A-61-62597, JP-A-61-
72098) or a method using polypropylene, polybutene, branched alkylbenzene, etc. as the base oil (
Japanese Unexamined Patent Publication No. 61-62598) and the like have been proposed, but none of them can be called a definitive solution.

[Problems to be Solved by the Invention] As a result of intensive studies by the present inventors in order to solve the above-mentioned various problems caused by microbial contamination of the water-soluble metal oil agent, the following results were found: (2) Ester compounds with a specific structure are less susceptible to assimilation by microorganisms. and that it has excellent lubricity as a base for metalworking fluids, and based on these findings, the present invention was completed.

That is, the present invention uses an ester compound having a specific structure that can replace conventionally used animal and vegetable oils and has excellent lubrication performance in terms of oil property improvement performance as a base for rot-resistant water-soluble metal working fluids. The purpose is to provide it as a drug.

[Means for Solving the Problems] The ester compound that is the base for water-soluble metal working fluid according to the present invention is characterized in that it is one or more ester compounds selected from the following group: .

(1) Esters of trimellitic acid and linear or branched aliphatic saturated or unsaturated alcohols having 2 to 20 carbon atoms, especially linear or branched saturated alcohols having 9 to 13 carbon atoms and esters containing a mixture of these alcohols as the alcohol component are preferred. Specifically, such esters include triisononyl trimellitate, tri-n-nonyl trimellitate, and mixtures thereof (hereinafter collectively referred to as rTM-9J), triindecyl trimellitate, tri-n-decyl trimellitate, and Mixtures of these (hereinafter collectively referred to as rTM-104), triisoundecyl trimellitate, tri-undecyl trimellitate, and mixtures thereof (hereinafter referred to as rTM-104)
They are collectively referred to as 114. ), triisotridecyl trimellitate, tri-n-tridecyl trimellitate, and mixtures thereof (hereinafter collectively referred to as rTM-13J).

(2) Ester of phosphoric acid and a linear or branched aliphatic saturated or unsaturated alcohol having 2 to 20 carbon atoms which may be substituted with a halogen group, especially a straight chain having 7 to 9 carbon atoms Preferred are esters containing as the alcohol component a shaped or branched alcohol or a mixture of these alcohols. Further, halogenated alcohols having 2 to 3 carbon atoms are also a type of preferable alcohol. Specifically, such esters include triisohebutyl phosphate, tri-n-heptyl phosphate, and mixtures thereof (hereinafter collectively referred to as rP-7J), triisooctyl phosphate, tri-n-octyl phosphate, and A mixture of these (hereinafter collectively referred to as IP-8J), tri(2-ethylhexyl) phosphate (hereinafter referred to as “P-8(E
H) Collectively referred to as j. ), triisononyl phosphate, tri-n-nonyl phosphate, and mixtures thereof (hereinafter collectively referred to as rP-9J), tris(2-chloroethyl) phosphate (hereinafter referred to as [P2 (C
E) Collectively referred to as j. ), etc. are exemplified.

(3) An ester of a linear or branched aliphatic saturated or unsaturated carboxylic acid having 2 to 20 carbon atoms and trimethylolpropane, especially a branched saturated carboxylic acid having 7 to 9 carbon atoms as an acid component. Nystere is preferred. Specifically, such esters include trimethylolpropane,
An example is tri(2-ethylhexylate) (hereinafter abbreviated as FTP-8J).

Specific composition examples of water-soluble metal working fluid compositions prepared by applying the ester compound according to the present invention are listed below.

For example, an emulsion-type cutting fluid is composed of the following component composition.

Base oil (e.g. machine oil) about 45-75% by weight, oiliness improver (product of the present invention) 5-30% by weight, extreme pressure additive O-50% by weight surfactant
15-35% by weight culm weight rust preventive agent O
- About 5% by weight, antioxidant O - about 1% by weight, antifoaming agent O - about 0.5% by weight, water O - about 10% by weight.

Further, an example of the composition of the soluble cutting fluid is as follows.

Base oil (e.g. machine oil) 0 to 25% by weight, oiliness improver (inventive product) 5 to 30% by weight, extreme pressure additive 0 to 20% by weight surfactant
20-80% by weight rust preventive agent 5
-40% by weight Antioxidant O - about 1% by weight, Antifoaming agent about 0-0.5% by weight, Water O - 70% by weight Water The ester compound according to the invention is blended to form a water-soluble metal oil agent. Surfactants used in preparing the composition include:
Polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene-
Polyoxypropylene condensates, sorbitan fatty acid esters such as sorbitan monooleate, nonionic surfactants such as fatty acid dialkanolamides, alkylbenzene sulfonates, alkyldiphenyl ether disulfonates, fatty acid metal salts, N-oleoyl sarcosine, etc. Examples include anionic surfactants such as sarcosinic acid derivatives, cationic surfactants such as carboxylic acid amine salts, and alanine-based amphoteric surfactants.

Furthermore, various additives that are commonly blended depending on the purpose are added to the metal oil. Specifically, phosphates, borates, alkylamines, etc. as rust preventives, 1,2-benzisothiazolin-3-one, 2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one as fungicides and preservatives. thiazole-based compounds such as 1, triazine-based compounds such as trishydroxyethyltriazine and hexahydrotriazine, other O-phenylphenols, sulfurized terpenes as extreme pressure additives, dibenzyl disulfide, dialkyl polysulfate, sulfurized olefins, Sulfur compounds such as sulfurized oils and fats, phosphorus compounds such as triaryl phosphates, triaryl phosphites, acidic phosphate ester amine salts, zinc alkyl dithiophosphate, halogen compounds such as chlorinated paraffins, chlorinated fatty acid alkyls, Organometallic compounds such as naphthene [a, lead dialkyldithiocarbamate, etc., silicone compounds as antifoaming agents, organic amines as DH regulators, alkali hydroxides, etc., di-tert-butyl-p- as antioxidants, etc. Examples include various additives such as cresol.

Thus, the ester compound according to the present invention can be blended as a base oil or oiliness improver for water-soluble metalworking fluids, and can be used as cutting oils, grinding oils, polishing oils, rolling oils, press oils, withdrawal oils, plastic working oils, Consists of various water-soluble metal oils such as drilling oil and wire drawing oil.

[Example] Hereinafter, the present invention will be described in detail with reference to Examples.

Examples 1 to 6 Six types of ester compounds according to the present invention were evaluated for rot resistance under aerobic conditions, biodegradability under anaerobic conditions, and load-bearing capacity for lubricity evaluation. It was measured. The results obtained are listed in Table 1.

The rot resistance and lubricity of each ester were evaluated by the following methods.

Resistance to spoilage (1) Resistance to spoilage under aerobic conditions Add 2% polypeptone water (p
H = 7 > 5 ml, and after sterilizing with pressurized steam at 120'C for 20 minutes, place the subject 0.2 m (4,0 V/V
%) and the following microbial sources at 0.1 d (2.0 V/V%)
and culture at 25°C for 14 days. Add 0.05 d of ether solution of 0.5% Sudan black B to this culture solution.
is added to stain the remaining specimens that have not been decomposed and assimilated. This degree of staining is compared with the degree of staining of a blank experimental solution, and the rot resistance is evaluated on the following four levels.

◎: Not decomposed at all.

○: Slightly decomposed.

△: Considerably decomposed.

X: Completely decomposed.

The following four types of microbial sources were applied.

(1) Activated sludge used in sewage treatment plants (2) Pseudomonas bacteria that decompose butyl stearate (hereinafter referred to as “
It is abbreviated as BS assimilating bacteria. ) (3) Spoiled cutting oil waste collected at metal processing sites ■ Emulsion type cutting oil waste (hereinafter abbreviated as "E waste") ■ Soluble type cutting oil waste (hereinafter abbreviated as "S waste") (2 )Evaluated by rot resistance and biodegradability (%) under anaerobic conditions. That is, 59 m of a medium for sulfate-reducing bacteria having the following composition and 5 g of a test substance are placed in a 500 d Sakaro flask, and after sterilization, 16 m of a microorganism source prepared by the method described below is added.

After replacing the inside of the flask with carbon dioxide, the flask is cultured with shaking at 30°C for 7 days. After extracting with n-hexane, the remaining test material that has not been decomposed and assimilated is collected, its weight is measured, and the biodegradability (%) is calculated.

Here, biodegradability (%) refers to the percentage difference between the test weight before decomposition and the test weight after decomposition with respect to the test weight before decomposition.

Preparation of microorganism source> In a 500 m Sakaro flask, add bouillon medium 95 with the following composition.
After sterilizing with pressurized steam at 120℃ for 20 minutes, putrefactive cutting oil waste liquid collected at the processing site (general bacteria count 7 x 10
A microorganism source (A) was prepared by adding 6 cells/rnll, pi-1=6.52>5d, and culturing at 30° C. for 2 days. In addition, a microorganism source (B) was prepared by culturing the medium for sulfate-reducing bacteria having the following composition in the same manner. A bulk weight mixture of the above microbial source (A) and microbial source (8) was used in the spoilage resistance test.

0 Bouillon medium composition (%) [pH = 7.0] Bonito onyx 0.5 Polypeptone 0.5 Salt 0.25 Iron powder 2 0 Medium composition for sulfate-reducing bacteria (%) [pH = 7.4] Phosphoric acid - Potassium hydrogen 0.05 ammonium chloride
0.1 Sodium sulfate 0. Calcium monochloride trihydrate 0.01 Magnesium sulfate heptahydrate
0.2 Lactic acid 0.25 Yeast extract
0.1 Ferrous sulfate heptahydrate 0.05 Ascorbic acid 0.02 Iron powder
2 Using a lubricity-type four-ball friction tester, Uesaka 3/4 inch ball (JIS B1501), vertical axis rotation speed 75 Orpm
The load-bearing capacity was measured at a measurement temperature of 25°C.

Comparative Example 1 A general-purpose machine oil (G-46) was used as a base oil, and its rot resistance, biodegradability, and load-bearing capacity were measured and evaluated according to the examples. The results obtained are listed in Table 1.

Comparative Examples 2 to 5 General-purpose butyl stearate (rB
It is abbreviated as u-3tJ. ), polyolefin oil, vegetable oil (rapeseed oil), and animal oil (beef tallow) were measured and evaluated for their rot resistance, biodegradability, and load-bearing capacity according to the examples.

The results obtained are listed in Table 1.

[Effects of the Invention] The ester compound according to the present invention is less susceptible to decay and has excellent lubricity than the base oil or oiliness improver of conventionally used metal working fluids. A water-soluble metal working oil composition containing the compound can maintain stable properties over a long period of time.

Patent applicant: Shin Nippon Rika Co., Ltd.

Claims (1)

[Scope of Claims] 1. A base for a water-soluble metal working fluid, which is characterized by being one or more ester compounds selected from the following group. (1) An ester of trimellitic acid and a linear or branched aliphatic saturated or unsaturated alcohol having 2 to 20 carbon atoms; (2) phosphoric acid and a carbon that may be substituted with a halogen group; (3) Esters with linear or branched aliphatic saturated or unsaturated alcohols having 2 to 20 carbon atoms; (3) esters with linear or branched aliphatic saturated or unsaturated carboxylic acids having 2 to 20 carbon atoms; , ester with trimethylolpropane.