JP6504342B2 - Water soluble metal processing oil - Google Patents

Description

  The present invention relates to a water-soluble metalworking fluid having high wettability to metals.

  Water-soluble metalworking oils are widely used in the field of plastic processing such as cutting, grinding, rolling, and quenching. Among them, water-soluble cutting oils are water-insoluble mineral oils, fats and oils, fatty acid esters with an emulsifier in combination, or water-soluble polyalkylene glycol derivatives as a base oil, compounded with carboxylic acids, organic amines, etc. It is used after dilution. The water-soluble cutting oil is required to have lubricity to reduce the friction between the tool and the workpiece, and the cooling property of the processing heat generated by the friction between the tool and the workpiece. In order to develop high lubricity and cooling properties, it is important to spread the water-soluble cutting oil to the processing point. However, due to the recent increase in finishing accuracy and demand for extension of tool life, the water-soluble metal-working oil conventionally used may not have sufficient wettability. In addition, due to the recent increase in processing speed, not only the reduction of generated bubbles in a short time which has been the conventional required performance, but also the foamability itself is required to be low. In addition, the water-soluble cutting oil is required to be uniform without separating the components.

  There have been many reports on water soluble metalworking fluids so far. A method using a polyoxypropylene-polyoxyethylene-polyoxypropylene triblock copolymer as a base oil has been reported (eg, Patent Document 1). Such water-soluble metalworking oils have low foamability, but may not be sufficient for the recent demand for wettability to metals.

  Methods using alkylene oxide adducts of nonionic surfactants and acetylene glycol have been reported (eg, Patent Document 2). Such water-soluble metalworking oils have low bubble formation, but may not be sufficient for recent high metal wettability requirements.

  A method of adding an ester type nonionic surfactant having a branched alkyl group has been reported, and an alkylene oxide adduct of isostearic acid has been reported as a specific example (for example, Patent Document 3). Such water-soluble metal-working oils are excellent in wettability to metals and excellent in reduction of bubbles in a short time, but may have high foamability and have a problem of hydrolysis resistance over time.

  Water-soluble belt conveyor lubricants using ethylene oxide / propylene oxide adducts of alcohols having a specific carbon number have been reported, and as specific examples, ethylene oxide / propylene oxide adducts of lauryl alcohol have been reported (for example, Patent Document 4). When such a compound is used in a water-soluble metalworking fluid, it has excellent wettability to metals, but may have high foamability, and the reduction of air bubbles in a short time may not be sufficient.

  Methods using ethylene oxide butylene oxide adducts of specific alcohols have been reported (eg, Patent Document 5). Water-soluble metalworking oils comprising such compounds have low solubility in water and separation may occur when base oils having low hydrophilicity are used. In addition, even when such compounds improve hydrophilicity by adjusting the added mole number of the oxyethylene group and the oxybutylene group, the generated foam may have a high ability to eliminate the bubbles, but the foamability may be high. .

  Thus, a water-soluble metal working oil which is stable without causing separation, has a sufficiently low foamability, and is highly wettable to metals has not been obtained yet.

Japanese Patent Application Laid-Open No. 8-231977 JP, 2012-201750, A Japanese Patent Application Laid-Open No. 2002-80882 JP, 2009-191126, A JP 2013-23662 A

  An object of the present invention is to provide a water-soluble metal working oil which is stable without causing separation, has a sufficiently low foamability, and has high wettability to metals.

The present invention relates to a water-soluble metalworking fluid characterized by containing (a) a compound represented by the formula (1) , (b) a compound represented by the formula (2) and (c) water. is there.

R ¹ -O- (EO) _m- (PO) _n -H (1)

(In the formula (1),
R ¹ is a 3,5,5-trimethylhexyl group.
EO is an oxyethylene group.
PO is an oxypropylene group.
m is an average added mole number of the oxyethylene group and is 1 to 10.
n is an average added mole number of the oxypropylene group and is 1 to 5;
m / (m + n) is 0.40 to 0.90. )

Z- [O- (AO) _a- (PO) _b ] _c- H (2)

(In formula (2),
Z is a residue from which a hydroxyl group of a 1 to 6-hydric alcohol is removed.
AO is a C2-C3 oxyalkylene group, The ratio of the oxyethylene group in AO is 70 to 100 weight%.
PO is an oxypropylene group.
a is an average added mole number of an oxyalkylene group having 2 to 3 carbon atoms, is 1 to 20, b is an average added mole number of an oxypropylene group, is 3 to 40, and c is 1 to 6 A x c is 3 to 30, b x c is 10 to 70, and a / (a + b) is 0.05 to 0.55.
The molecular weight of the compound of formula (2) is 1000 to 5000. )

  The water-soluble metalworking oil of the present invention is stable without separation, sufficiently low in foamability, and high in wettability to metal, thus achieving improvement in finishing accuracy of metal processing and prolongation of tool life. can do.

The water-soluble metal-working oil having high wettability to metals of the present invention comprises the compound represented by the formula (1).
R ¹ -O- (EO) _m- (PO) _n -H (1)

R ¹ in the formula (1) is a 3,5,5-trimethylhexyl group. When the carbon number of R ¹ is less than 9, the wettability to metals is insufficient, and when it is more than 9, the foamability is high. In addition, even when the carbon number of R ¹ is 9 and is not a 3,5,5-trimethylhexyl group (for example, in the case of an isononyl group or an n-nonyl group), the wettability to metal is insufficient, Foaminess increases.

  EO in Formula (1) is an oxyethylene group. When the carbon number of EO is larger than 2, the hydrophilicity is reduced.

  PO in Formula (1) is an oxypropylene group. When the carbon number of PO is less than 3, the foamability is high, and when it is more than 3, the hydrophilicity of the water-soluble metalworking oil decreases.

  M in Formula (1) is an average added mole number of a C2-C3 oxyalkylene group, and is 1-10. When m is smaller than 1, the hydrophilicity is reduced, and when it is larger than 10, the wettability to metal is insufficient. m is preferably 2 or more. In addition, m is preferably 8 or less, more preferably 5 or less.

  N in Formula (1) is an average added mole number of an oxypropylene group, and is 1-5. When n is smaller than 1, the wettability to metal is insufficient and the foamability is high, and when it is larger than 5, the hydrophilicity is reduced. n is preferably 3 or more. Also, n is preferably 4 or less. When n is 3 to 4, due to the hydrophobicity of the continuous oxypropylene group, the interaction between the hydroxyl group and water is reduced, the stability of the foam film is reduced, and the foamability is reduced.

  M / (m + n) in Formula (1) is 0.40 to 0.90. When m / (m + n) is less than 0.40, the hydrophilicity decreases, and when it is greater than 0.90, the hydrophilicity of the water-soluble metalworking oil decreases. m / (m + n) is preferably 0.40 to 0.75, more preferably 0.40 to 0.60.

  The compound represented by the formula (1) can be obtained by a conventionally known alkylene oxide addition reaction. For example, it can be obtained by addition polymerization of ethylene oxide to 3,5,5-trimethyl-1-hexanol in the presence of an alkali catalyst and then addition polymerization of propylene oxide.

  The water-soluble metal-working oil of the present invention is a water-soluble lubricating oil used for cutting, grinding, plastic working, etc. Specifically, cutting oil, grinding oil, rolling oil, forging oil, quenching oil etc. are mentioned Be Preferably, they are cutting oil, grinding oil and rolling oil, more preferably cutting oil.

The metalworking oil of the present invention preferably contains (b) a compound represented by the formula (2), and (c) water, in addition to the compound represented by the (a) formula (1).
Z- [O- (AO) _a- (PO) _b ] _c- H (2)

(Z is a residue from which a hydroxyl group of a 1 to 6-hydric alcohol is removed, AO is an oxyalkylene group having 2 to 3 carbon atoms, and the ratio of oxyethylene group in AO is 70 to 100% by weight. PO is an oxypropylene group, a is an average addition mole number of an oxyalkylene group having 2 to 3 carbon atoms, and is 1 to 20. b is an average addition mole number of an oxypropylene group, and 3 to 40. C is 1 to 6. a × c is 3 to 30, b × c is 10 to 70, and a / (a + b) is 0.05 to 0.55 Molecular weight is 1000 to 100 It is 5000.)

  Z in Formula (2) is the residue except the hydroxyl group of the 1 to 6-valent alcohol. Specific examples of the compound having Z as a residue include methanol, ethanol, n-propanol, 2-propanol, n-butanol, 2-butanol, t-butanol, isobutanol, n-hexanol and n- as a monohydric alcohol. And octanol, 2-ethylhexanol, n-decanol, isodecanol, dodecanol, oleyl alcohol, cyclohexanol, methylcyclohexanol, phenol and the like, and dihydric alcohols such as ethylene glycol, propylene glycol, 1,2-butanediol, 1,2 3-butanediol, 1,4-butanediol, neopentyl glycol, bisphenol A and the like are mentioned, glycerin, trimethylolpropane and the like are mentioned as a trihydric alcohol, and pentaerythritol as a tetrahydric alcohol Tall, diglycerin, include such as methyl glucoside, xylitol, triglycerol and the like as pentavalent alcohols, sorbitol, dipentaerythritol, and the like as hexavalent alcohol. Preferably it is a dihydric alcohol, more preferably ethylene glycol.

  AO of the compound represented by the formula (2) is an oxyalkylene group having 2 to 3 carbon atoms, and specific examples thereof include an oxyethylene group and an oxypropylene group. The proportion of oxyethylene groups in AO is 70 to 100% by weight. However, the total amount of oxyethylene and oxypropylene groups constituting AO is 100% by weight.

  When the carbon number of AO is more than 3, the hydrophilicity is reduced. When the proportion of oxyethylene groups in AO is less than 70% by weight, the hydrophilicity is reduced. The proportion of oxyethylene groups in AO is preferably 80% by weight or more. As for AO, it is particularly preferable that the oxyethylene group occupies 100% by weight. When AO is 2 or more types, the oxyethylene group and the oxypropylene group may be added in the form of a block in the order of polyoxypropylene group / polyoxyethylene group or may be added in a random form; Is preferably added to

  A of the compound shown by Formula (2) is the average added mole number of a C2-C3 oxyalkylene group, and is 1-20. When a is smaller than 1, the hydrophilicity is reduced, and when it is larger than 20, the hydrophilicity is increased and the cloud point is increased, the amount of deposition on the metal surface is reduced, and the processability is reduced. a is preferably 2 or more, more preferably 3 or more. Further, a is preferably 18 or less, more preferably 15 or less.

  B of the compound shown by Formula (2) is an average added mole number of an oxypropylene group, and is 3-40. When b is smaller than 3, the foamability is high, and when it is larger than 40, the hydrophilicity decreases.

  C of the compound shown by Formula (2) is 1-6. When c is larger than 6, the handleability is reduced. c is preferably 1 to 3, more preferably 2 to 3.

  A × c of the compound represented by the formula (2) is 3 to 30. When a × c is smaller than 3, the hydrophilicity is reduced, and when it is larger than 30, the hydrophilicity is increased, the cloud point is increased, and the amount of deposition on the metal surface is reduced to deteriorate the processability. a × c is preferably 5 or more, more preferably 7 or more. Further, a × c is preferably 25 or less, more preferably 23 or less.

  Bxc of the compound shown by Formula (2) is 10-70. When b × c is smaller than 10, the foamability is high, and when it is larger than 70, the hydrophilicity is reduced. b × c is preferably 15 or more, more preferably 20 or more. Further, b × c is preferably 60 or less, more preferably 50 or less.

  A / (a + b) of the compound shown by Formula (2) is 0.05-0.55. When a / (a + b) is less than 0.05, the hydrophilicity is reduced, and when it is greater than 0.55, the hydrophilicity is increased, the cloud point is increased, and the amount of deposition on the metal surface is reduced to improve processability descend. a / (a + b) is preferably 0.10 or more, more preferably 0.15 or more. Further, a / (a + b) is preferably 0.50 or less, more preferably 0.35 or less

  The molecular weight of the compound shown by Formula (2) is 1000-5000. When the molecular weight is less than 1000, the processability is reduced, and when it is more than 5,000, the viscosity is high and handling is difficult. The molecular weight of the compound represented by the formula (2) is preferably 1200 or more, more preferably 1500 or more. Further, the molecular weight of the compound represented by the formula (2) is preferably 4000 or less, more preferably 3500 or less.

  Furthermore, the water-soluble cutting oil of the present invention can be used in combination with additives such as a rust inhibitor, an antifoamer, a preservative, a metal deactivator, a friction modifier and the like. The rust inhibitor includes alkanolamine salts of carboxylic acids, alkanolamine salts of dicarboxylic acids, alkyl benzene sulfonates, dinonyl naphthalene sulfonates, and alkenyl succinic acid derivatives. Examples of the antifoaming agent include silicone oil, fluorosilicone oil, fluoroalkyl ether, polyalkylene glycol antifoaming agent and the like. Examples of metal deactivators include benzotriazole, thiazoles, imidazolines, pyrimidine derivatives and the like. Examples of the friction modifier include fatty acids, fatty acid esters, alcohols and the like.

Hereinafter, the present invention will be described in more detail by way of examples.
Example 1
Synthesis Example 1
In a 5 L autoclave, 433 g (3 moles) of 3,5,5-trimethyl-1-hexanol (trade name: nonanol, manufactured by KH Neochem Co., Ltd.) and 6 g of potassium hydroxide are charged, and the air in the autoclave is replaced with nitrogen Then, the temperature was raised to 120 ° C. while stirring. Next, 1058 g (24 mol) of ethylene oxide was dropped using a dropping device, and the mixture was stirred for 1 hour. Furthermore, 523 g (9 mol) of propylene oxide was dropped by a dropping device, and the mixture was stirred for 2 hours. Thereafter, the reaction product was taken out of the autoclave, neutralized with hydrochloric acid to adjust to pH 6 to 7, and the pressure was reduced to 6.7 kPa or less to remove contained water, and treated at 100 ° C. for 1 hour. Further filtration was performed to remove the salt formed after treatment to obtain an ethylene oxide 8 mole / propylene oxide 3 mole block copolymer of 3,5,5-trimethyl-1-hexanol. The structure of the compound synthesized was identified by ¹ H-NMR analysis. The structure of Compound A1 synthesized is shown in Table 1.

<Preparation of water-soluble cutting oil>
In a 300 mL four-necked flask, 134 g (67% by weight) of water, 10 g (5% by weight) of caprylic acid, 4 g (2% by weight) of sebacic acid, and 30 g (15% by weight) of triethanolamine are added. Stir for a minute. The mixture was cooled to 25 ° C., compound A1 (1% by weight) and 20 g (10% by weight) of a polyalkylene glycol derivative were added, and the mixture was stirred for 30 minutes to prepare a water-soluble cutting oil.
The polyalkylene glycol derivative used in this example is a polypropylene oxide-polyethylene oxide-polypropylene oxide triblock copolymer, and the total addition mole number of propylene oxide is 28 moles, and the addition mole number of ethylene oxide is 11 moles, The molecular weight is 2100 and the cloud point of a 1% aqueous solution is 33.degree.
The composition of the prepared water-soluble cutting oil is shown in Table 2.

<Evaluation of presence or absence of separation at 25 ° C.>
100 g of the prepared water-soluble cutting oil was placed in a 100 mL glass bottle, and the temperature was adjusted to 25 ° C. The presence or absence of separation was evaluated based on the following criteria. About what did not separate, after leaving still in a 25 degreeC thermostat for 3 months, the presence or absence of isolation | separation was evaluated by the same reference | standard. The results are shown in Table 3.

○: uniform without separation ×: separated

<Evaluation of wettability>
The water-soluble cutting oil was diluted tenfold with water to prepare a tenfold dilution. The contact angle of the 10-fold diluted solution to the aluminum plate (A1050P specified in JIS H4100) was measured and evaluated according to the following criteria. The results are shown in Table 3.

:: Contact angle less than 30 ° ○: Contact angle 30 ° or more and less than 40 ° ×: Contact angle 50 ° or more

<Evaluation of low foamability>
In a 100 mL glass bottle, 30 g of a 10-fold diluted solution of a water-soluble cutting oil was placed, temperature was adjusted to 25 ° C., and then it was shaken by hand for 10 seconds. The height of the foam from the liquid surface immediately after shaking was measured, and the low foamability was evaluated based on the following criteria. The results are shown in Table 3.

◎: Less than 5 mm of bubbling ○: More than 5 mm and less than 10 mm of bubbling ×: 30 mm or more of bubbling

<Evaluation of the disappearance of bubbles>
In a 100 mL glass bottle, 30 g of a 10-fold diluted solution of a water-soluble cutting oil was placed, temperature was adjusted to 25 ° C., and then it was shaken by hand for 10 seconds. The height of the foam from the liquid surface after standing for 5 minutes was measured, and the defoaming property of the foam was evaluated based on the following criteria. The results are shown in Table 3.

◎: Less than 5 mm of bubbling ○: More than 5 mm and less than 10 mm of bubbling ×: 30 mm or more of bubbling

[Examples 2 to 6]
Compounds A2 to A5 represented by the formula (1) shown in Table 1 are synthesized in the same manner as in Example 1, and as shown in Table 2, water-soluble cutting oils of Examples 2 to 6 are prepared, I made an evaluation. The results are shown in Table 3.

Comparative Example 1
A water-soluble cutting oil shown in Table 2 was prepared and evaluated in the same manner as in Example 1 except that the compound represented by the formula (1) was not added. The results are shown in Table 3.

[Comparative Examples 2 to 8]
Compounds a1 to a7 represented by Formula (1) shown in Table 1 were synthesized by the same method as Example 1, and preparation and evaluation of a water-soluble cutting oil shown in Table 2 were performed. The results are shown in Table 3.

Comparative Example 9
The same method as in Example 1 except that ethylene oxide 8-mole butylene oxide 2-mole block copolymer a8 of 3,5,5-trimethyl-1-hexanol was used instead of the compound represented by the formula (1) Then, a water-soluble cutting oil shown in Table 2 was prepared and evaluated. The results are shown in Table 3.

Comparative Example 10
Water-soluble cutting shown in Table 2 in the same manner as in Example 1 except that ethylene oxide 7 mole / propylene oxide 2 mole block copolymer a9 of isostearic acid was used instead of the compound represented by the formula (1) The oil was prepared and evaluated. The results are shown in Table 3.

Comparative Example 11
Example 1 is the same as Example 1 except that ethylene oxide 10-mole adduct a10 of 2,4,7,9-tetramethyl-5-decyne-4,7-diol is used instead of the compound represented by formula (1) The water-soluble cutting oil shown in Table 2 was prepared and evaluated by The results are shown in Table 3.

  From the results in Table 3, it is found that the water-soluble cutting oils of Examples 1 to 6 are stable without causing separation, have high wettability to metal, high ability to eliminate air bubbles, and sufficiently low foamability. I understand that. As a result of performing cutting using the water-soluble cutting oil of Examples 1-6, the precision of metal processing could be improved and the tool life could be extended.

  On the other hand, Comparative Example 1 did not use the compound represented by the formula (1) of the present invention, so the wettability to metal was insufficient.

In Comparative Example 2, the wettability to metal was insufficient because the average added mole number of the oxyalkylene group having 2 to 3 carbon atoms of the compound represented by the formula (1) was larger than the range of the present invention.
In Comparative Example 3, since the average added mole number of the oxypropylene group of the compound represented by the formula (1) is larger than the range of the present invention, the water-soluble cutting oil separated.

  In Comparative Example 4, since the ratio of the oxyalkylene group having 2 to 3 carbon atoms in the total of the oxyalkylene group having 2 to 3 carbon atoms and the oxypropylene group in the compound represented by the formula (1) is larger than the scope of the present invention , Wettability to metal is insufficient, and foamability is high.

  In Comparative Example 5, the ratio of the oxyalkylene group having 2 to 3 carbon atoms in the total of the oxyalkylene group having 2 to 3 carbon atoms and the oxypropylene group in the compound represented by the formula (1) is smaller than the range of the present invention , Water soluble cutting oil separated.

In Comparative Example 6, the carbon number of the alkyl group of the compound represented by the formula (1) was smaller than the range of the present invention, and the wettability to metal was insufficient.
In Comparative Example 7, since the carbon number of the alkyl group of the compound represented by the formula (1) is larger than the range of the present invention, the foamability is high and the defoamability of the bubbles is low.
Comparative Example 8 uses an isononyl group having the same carbon number as the alkyl group of the compound represented by the formula (1) instead of the 3,5,5-trimethylhexyl group, but the foamability is high. became.

In Comparative Example 9, a water-soluble cutting oil is used since ethylene oxide 8-mole butylene oxide 2-mole block copolymer of 3,5,5-trimethyl-1-hexanol is used instead of the compound represented by the formula (1). Separated.
In Comparative Example 10, since the ethylene oxide 7 mole / propylene oxide 2 mole block copolymer of isostearic acid is used instead of the compound represented by the formula (1), the water-soluble cutting oil is separated over time, and the rise occurs. Foaminess has increased.
Comparative Example 11 uses a 10-mole ethylene oxide adduct of 2,4,7,9-tetramethyl-5-decyne-4,7-diol instead of the compound represented by the formula (1). The wettability to the surface was insufficient.

Claims (1)

A water-soluble metalworking oil comprising (a) a compound represented by the formula (1) , (b) a compound represented by the formula (2) and (c) water .

R ¹ -O- (EO) _m- (PO) _n -H (1)

(In the formula (1),
R ¹ is a 3,5,5-trimethylhexyl group.
EO is an oxyethylene group.
PO is an oxypropylene group.
m is an average added mole number of the oxyethylene group and is 1 to 10.
n is an average added mole number of the oxypropylene group and is 1 to 5;
m / (m + n) is 0.40 to 0.90. )

Z- [O- (AO) _a- (PO) _b ] _c- H (2)

(In formula (2),
Z is a residue from which a hydroxyl group of a 1 to 6-hydric alcohol is removed.
AO is a C2-C3 oxyalkylene group, The ratio of the oxyethylene group in AO is 70 to 100 weight%.
PO is an oxypropylene group.
a is an average added mole number of an oxyalkylene group having 2 to 3 carbon atoms, is 1 to 20, b is an average added mole number of an oxypropylene group, is 3 to 40, and c is 1 to 6 A x c is 3 to 30, b x c is 10 to 70, and a / (a + b) is 0.05 to 0.55.
The molecular weight of the compound of formula (2) is 1000 to 5000. )