JPS634880B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to cutting and a water-soluble cutting fluid used for cutting (hereinafter referred to as "mizukiri"). More specifically, the present invention relates to an improved drainer with less microbial deterioration and less iron ion elution. (Technical background) Metal cutting processing, water cutting used for cutting processing is intended for mineral oil, oil, extreme pressure additives, surfactants, antifoaming agents, metal anticorrosive agents, antioxidants, preservatives and antifungal agents, etc. The composition is mixed as appropriate depending on the composition. Mizukiri is usually diluted 10 to 100 times with water. This diluted liquid is called coolant. Coolants are required to have performance that improves machinability (primary performance) and performance related to workability and others (secondary performance). Among these, secondary performance includes good rust prevention, resistance to deterioration, ease of management, harmlessness to the human body, and less foaming and odor. Although the emphasis differs depending on the purpose and conditions of use, a drainer must have a good balance of the above-mentioned performances. Preventing microbial deterioration of coolants is a very important issue. As coolant decay progresses, primary and secondary performance will deteriorate, and
Bad odors also make the work environment worse. If the frequency of oil changes due to spoilage increases, it will be disadvantageous in terms of cost. Furthermore, if mold grows in the coolant, it not only reduces the primary performance and secondary performance, but also causes clogging of pipes in the environmental system. In addition to the above, elution of iron ions is another cause of coolant deterioration. When metal processing is continued using coolant, iron ions gradually elute into the coolant, which causes the coolant to turn reddish-brown, and
A reddish-brown substance adheres to the surface of the workpiece, spoiling its appearance. Therefore, the operator must perform work to remove the colored substance. Further, when the material of the workpiece is an iron-based metal, the above-mentioned deposits may promote the formation of rust on the workpiece. (Prior Art) In order to prevent microbial deterioration of the coolant, various antibacterial substances are added to drainers, but the deterioration of the coolant cannot be prevented for a long period of time, and the situation is not satisfactory. In order to prevent the elution of iron ions, various studies have been conducted on the composition of cutting oil.
No effective means have been found. (Objective of the Invention) Among the above-mentioned properties, the present invention is particularly superior in that it is resistant to deterioration, more specifically in that it is resistant to microbial deterioration, that is, it is resistant to rotting, resistant to the growth of mold, and that there is little elution of iron ions. It provides a water drainer. (Structure of the Invention) As a result of intensive research, the present inventor has found that by adding a special amine, the resistance to microbial deterioration is significantly improved without impairing the performance of draining, and the elution of iron ions is reduced. The inventors have discovered that it is possible to do so and have arrived at the present invention. The present invention uses an amine represented by the following formula (hereinafter referred to as P amine) in a colander in which mineral oil, fats and oils, extreme pressure additives, surfactants, antifoaming agents, metal anticorrosives, antioxidants, etc. are mixed as necessary. It is a drainer characterized by containing. RO(CH ₂ ) _o NH ₂ where R is a hydrogen atom or an alkyl group having 1 to 24 carbon atoms, an alkenyl group, a cycloalkyl group,
The alkyl group is an aryl group, an aralkyl group or an aryl group, and n is an integer of 2 to 18. Components of the present invention will be explained in detail below. <P-amine> Examples of P-amine that can be used in the present invention are as follows. (R is an alkyl group) 2-ethylhexyloxypropylamine (Examples 1 and 5), lauryloxyethylamine (Examples 2 and 6), 2-ethylhexyloxydodecylamine (Examples 3 and 7), lauryloxy Butylamine (Examples 4 and 8), (where R is _an alkenyl group) _CH2 =CH- _CH2 -O _{- CH2CH2NH22} -propenyloxyethylamine 9-octadecenyloxypropylamine 1-Methyl-2-propenyloxyhexylamine (R is a cycloalkyl group) Cyclohexyloxypropylamine 2-methylcyclohexyloxyethylamine (R is an alkylaryl group) 3,5 dimethylphenyloxyoctylamine 3,5 dinonylphenyloxypropylamine (R is an aralkyl group) benzyloxypropylamine P-tertbutylbenzyloxyoctylamine (R is an aryl group) Phenyloxypropylamine In the present invention, P amine is contained in the coolant.
Preferably, the amount is 0.001 to 1% by weight, more preferably 0.005 to 0.5% by weight.
If it is less than 0.001% by weight, the effect of the present invention will not be achieved, and if it exceeds 1% by weight, the effect will not improve and it will be uneconomical. P
The amine may be added to the drain stock solution or may be added to the coolant. <Other components> In the present invention, mineral oil, fats and oils, extreme pressure additives, surfactants, antifoaming agents, metal anticorrosives, antioxidants, etc. can be arbitrarily selected from those conventionally used for draining. It can be used as (Manufacturing method) In order to manufacture the water-soluble cutting fluid of the present invention, each component may be mixed according to a conventional method. (Example) Next, the present invention will be described with reference to Examples. However, the present invention is not limited to this in any way. Table 1 lists the composition of the emulsion type and Table 2 lists the composition of the soluble type drainer. (Numbers indicate weight %).

【table】

【table】

[Table] The following experiments were conducted to evaluate the performance of the drainers shown in Tables 1 and 2. (1) Preparation of sample solution Dilute the drainers of the Examples and Comparative Examples listed in Table-1 and Table-2 with sterile water, and dilute the drainers of Table-1 to 3% by weight and the drainers of Table-2 to 2% % and used as a sample solution. (2) Microbial deterioration resistance test Pour 400 ml of each sample solution into a sterilized 500 ml flat-bottomed flask, and use this as a starter to make a putrid emulsion (number of viable bacteria: 2 x 10 ⁸ cells/ml, number of fungi: 1 x 10 ⁴
pieces/ml) 1% by weight after starting the experiment 1, 2, 4,
The cells were inoculated at intervals of 8, 13, and 17 days, and cultured with shaking (rotation speed: 200 rpm) at 30°C for 21 days. and 0,
On days 3, 7, 14, and 21, a portion of each sample solution was aseptically collected, and the number of viable bacteria and fungi was measured.
At the same time, PH measurement, changes in appearance, and odor were observed. Furthermore, the rust prevention performance was also observed. In addition, the number of viable bacteria was measured by the plate counting method using an ordinary agar medium. Fungal counts were determined by plate counting using potato dextrose agar medium supplemented with antibiotics (chloramphenicol and tetracycline). In addition, rust prevention properties were observed using the cast iron chip method. That is, about 15 g of dry-cut casting chips (FC-25, 8-12 mesh) was collected in a Petri dish (inner diameter about 60 mm), about 25 ml of sample liquid was added to it, and after shaking thoroughly, about 4
It was left standing for a minute. Next, the sample solution was removed by a decanting method, and the state of rust generated on the Petri dish was examined over time. Tables 3 and 4 show the measurement results over time. From the results in Tables 3 and 4, it is clear that the colander of the present invention is superior in microbial resistance to the conventional colander.

【table】

【table】

[Table] Note 1) Appearance change ○: No change △: Slight gray-black color ×: Black color Note 2) Odor ○: No putrid odor △: Slightly putrid odor ×: Putrid odor Note 3) Rust prevention performance ◎ ：No rust ○：
Rust occurs at several points ×: Rust occurs at more than 10 points

【table】

【table】

[Table] (3) Iron ion elution prevention ability test 400 ml of the sample solution prepared by the method in (1) above and dry-cut casting chips (FC-25, 8
~12 meshes) was placed in a 500 ml Erlenmeyer flask, sealed with a cotton plug, and shaken at 37°C for 20 days (rotation speed: 150 rpm) to degrade the sample solution. After cooling, it was filtered through No. 5A filter paper to obtain a degraded liquid. Observing changes in appearance of this deteriorated liquid,
The iron ion concentration was measured. The results are shown in Table-5.

[Table] Note 4 Appearance change: ○ No change × Reddish browning Note 5 Iron ion concentration: Measured by spectrophotometric method.
The iron ion concentration of the new solution was 1 ppm or less for all samples.
From the results in Table 5, it is clear that the drainer of the present invention has a better ability to prevent iron ion elution than the conventional drainer. (Effects of the Invention) In the drainer of the present invention, the coolant is less likely to rot, mold is less likely to grow, and less iron ions are leached out, and it is not inferior to conventional drainers in other performances.

Claims (1)

[Scope of Claims] 1. A water-soluble cutting fluid characterized by containing an amine represented by the following formula. RO(CH ₂ ) _o NH ₂ where R is an alkyl group, alkenyl group, cycloalkyl group, alkylaryl group, aralkyl group or aryl group having 1 to 24 carbon atoms. n is 2~
It is an integer of 18.