JP3533423B2 - Lubricating oil for press working - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press working lubricating oil used when press working a metal plate.

[0002]

2. Description of the Related Art When a metal plate is pressed, a lubricating oil generally called a press oil is used. This press working lubricating oil plays an important role in controlling friction between the die and the worked metal plate during pressing and in preventing seizure.

The control of friction is mainly determined by the viscosity of the lubricating oil and the action of the oiliness improver, and the prevention of seizure is brought about by the extreme pressure additive added to the lubricating oil. Compounds containing sulfur, chlorine, and phosphorus are known as extreme pressure additives, and these undergo a chemical change under extreme pressure conditions and react with a metal to form a film at the friction interface, and this film forms a metal with the metal. It is said that the contact with the processed metal plate is relaxed to prevent seizure. In addition to these, there are rust inhibitors and anticorrosion agents for protecting the processed metal plate from rust and corrosion. These oiliness improvers, extreme pressure additives, rust inhibitors, etc. are collectively called additives. On the other hand, what is called a base oil includes synthetic oils such as mineral oil, polyolefin and polybutene. These uniformly dissolve the above-mentioned additives and send them to the lubrication interface,
Has a career function. However, these base oils generally have poor lubricity as compared with the above-mentioned oiliness improver and extreme pressure additive. Thus, the lubricating oil for press working is composed of the base oil and the additive, and its performance is important for pressing the metal plate.

However, the conventional lubricating oil for press working is troublesome in that the press oil adhering to the metal plate after pressing must be washed.
A chlorine-containing hydrocarbon solvent such as 1,1,1-trichloroethane or trichlorotrifluoroethane has been used as a cleaning agent for removing the press oil adhering to the processed metal plate. However, although chlorine-containing hydrocarbon solvents are non-flammable by themselves and have the advantage of being excellent in drying property, due to environmental pollution such as ozone layer depletion, these legal use regulations have come to be enforced. There is an urgent need to develop alternative cleaning agents. At present, water-based, alcohols, low boiling point petroleum hydrocarbon oils, etc. are being examined as alternative cleaning agents to replace these, but conventional chlorine-containing hydrocarbons such as 1,1,1-trichloroethane and trichlorotrifluoroethane. It has been pointed out that it is inferior to solvents in terms of handling and cleaning properties.

Based on such a background, as a performance of the lubricating oil for press working, there is a strong demand for the development of a lubricating oil which has a high detergency and does not require a degreasing step, that is, a lubricating oil which can be applied without the degreasing step. Lubricants satisfying these requirements to a certain extent, using a petroleum hydrocarbon oil which is volatile at room temperature and pressure as a base oil as a lubricating oil for press working, and further increasing the blending ratio of the base oil to the additive to 90% by weight or more. Oil is provided. This lubricating oil has made it possible to reduce the degreasing load and eliminate the degreasing process, but the deterioration of the lubricating performance has caused problems such as shortened tool life and reduced quality of processed products.

[0006]

The lubricating oil containing a volatile petroleum hydrocarbon oil as the main component of the base oil can reduce the amount of volatile residues and reduce or eliminate the degreasing load. However, problems such as the limited processing range that can be covered, the shortening of mold life and the deterioration of product quality have occurred again. Therefore, the main object of the present invention is to provide a lubricant for press working which has a high lubricating effect such that the degreasing load can be reduced or omitted, and the mold life and product quality are not deteriorated. To do.

[0007]

According to the present invention, the object of the present invention is to have a flash point of 30 ° C. or higher and a boiling point under atmospheric pressure of 265 ° C. or lower, and the following formula (I):

[Chemical 4] In the formula, a and b independently represent an integer of 1 to 6, and x and
And y independently represent 0 or 1. Also, R ¹ and
R ² is independently an alkyl group having 30 or less carbon atoms,
Alkyl group, alkylphenyl group, benzyl group or
An alkylbenzyl group is shown, and the alkyl moiety in each group
May be linear or branched, and the alkyl moiety
The hydrogen atom in is replaced with a chlorine atom or a fluorine atom.
It has been found to be achieved by a lubricating oil for pressing, characterized in that it contains an organic carbonate of the formula:

The lubricating oil for press working of the present invention will be described in more detail below. The organic carbonate used in the lubricating oil for press working of the present invention has a flash point of 30.
And a boiling point at atmospheric pressure of 265 ° C or lower,
It is preferably in the range of 100 to 250 ° C.

The organic carbonate is represented by the following formula (I)

[0010]

[Chemical 2]

In the formula, a and b each independently represent an integer of 1 to 6, and x and y each independently represent 0 or 1. R ¹ and R ² independently represent an alkyl group having 30 or less carbon atoms, a cycloalkyl group, an alkylphenyl group, a benzyl group or an alkylbenzyl group, and the alkyl moiety in each group is either linear or branched. And the hydrogen atom in the alkyl moiety may be substituted with a chlorine atom or a fluorine atom,

Compounds represented by are preferred.

The organic carbonate represented by the general formula (I) is a compound represented by the formula (I) -1 (both x and y are 0) consisting of a simple carbonate structure as shown below, and Of formula (I) -2 (where at least one of x or y is 1
The compound represented by the formula

[0014]

[Chemical 3]

First, the compound represented by formula (I) -1 will be described. R ¹ or R ² independently represents a group selected from linear or branched alkyl having 1 to 30 carbon atoms, cycloalkyl, alkenyl, alkylphenyl, benzyl and alkylbenzyl. R ¹
Advantageously, and R ² are independently an alkyl group having 30 or less, preferably 20 or less, particularly preferably 15 or less carbon atoms, in which case the alkyl group may be linear or branched, and The hydrogen atom of the alkyl group may be at least partially substituted with a chlorine atom or a fluorine atom.

Specific examples of the organic carbonate represented by the general formula (I) -1 include, for example, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, dibutyl carbonate, dipentyl carbonate,
Dihexyl carbonate, diheptyl carbonate, dioctyl carbonate, di-2-ethylhexyl carbonate, dilauryl carbonate, ditridecyl carbonate, ditetradecyl carbonate, dihexadecyl carbonate, di (hexyldecyl) carbonate, dioctadecyl carbonate, dieicosanyl carbonate , Didocosanyl carbonate, di (octyldodecyl) carbonate, ditetracosanyl carbonate, di (trifluoroethyl) carbonate, di (perfluoropentyl) carbonate, di (perfluorohexyl) carbonate, methyl ethyl carbonate, methyl isopropyl carbonate , Methyl (n-propyl) carbonate, methyl butyl carbonate, methyl hexyl carbonate, methyl Heptyl carbonate, methyl octyl carbonate, methyl nonyl carbonate, methyl decyl carbonate, methyl dodecyl carbonate, octyl decyl carbonate, diaryl carbonate, dibutenyl carbonate, didodecenyl carbonate, dioleyl carbonate, dielaidyl carbonate, dilinoleyl carbonate, Examples include dilinolenyl carbonate, diphenyl carbonate, dicresyl carbonate, dibutylphenyl carbonate, dinonylphenyl carbonate, dibenzyl carbonate, dicyclohexyl carbonate, dimethylcyclohexyl carbonate, diphenylmethyl carbonate, furfuryl carbonate, ditetrahydrofurfuryl carbonate. it can.

Next, the compound represented by the formula (I) -2 will be described. In the formula (I) -2, a and b are independently an integer of 1 to 6, preferably an integer of 1 to 5,
More preferably, it is an integer of 2-4. If a and b exceed 6, the manufacturing process becomes complicated. R ¹ and R ² are the same as defined in the above formula (I) -1, and preferable ones are also preferable. The compound of formula (I) -2 generally has a higher flash point than the compound of formula (I) -1.

Specific examples of the compound represented by the above formula (I) -2 include, for example, methyl (methoxypropyl) carbonate, di (methoxypropyl) carbonate, methyl (ethoxypropyl) carbonate, di (ethoxypropyl) carbonate, Examples thereof include di (butoxyethyl) carbonate, butyl (butoxyethyl) carbonate, butyl (butoxybutyl) carbonate, butoxyethyl (butoxypropyl) carbonate, di (propoxypropyl) carbonate and di (butoxypropyl) carbonate.

The physical properties of some of the above organic carbonates are shown in Table 1 below.

[0020]

[Table 1]

Next, the method for producing the organic carbonate of the present invention will be described separately for each of the compounds of formula (I) -1 and formula (I) -2. As the method for producing the compound of formula (I) -1, the following (Production method 1) and (Production method 2)
The reaction route described above is typical.

[0022](Production method 1)In the presence of a catalyst, dimethyl car
Bonate, diethyl carbonate, dipropyl carbonate
Lower dialkyl carbonates such as ether and R¹Or R²of
Alcohol (R ¹OH or R²OH) with ester exchange
A method for producing a carbonic acid ester by a conversion reaction.

(Production Method 2) Alcohol of R ¹ or R ² (R ¹ OH or R ² O in the presence of an organic base or an inorganic base )
A method for producing a carbonic acid ester by reacting H) with phosgene. Since the production method I does not use phosgene, which is highly toxic, pollution control, waste treatment steps, etc. are reduced. On the other hand, the compound of the formula (I) -2 is a compound of the formula I as the alcohol R ¹ (OC _a H _2a ) _x OH or R ² (OC _b
It can be produced by transesterification using H _2b ) _y OH.

In the lubricating oil for press working of the present invention, the organic carbonate is used as a base material (base oil), and the content thereof may be 5% by weight or more, preferably 40% by weight or more. is there.

The lubricating oil of the present invention, as described above,
In addition to the content of the organic carbonate in the above-mentioned proportion, an additive which is usually added to a lubricating oil for press working can be blended in an amount of 10% by weight or less, which is preferable. Types of additives are oiliness improvers, extreme pressure additives, rust inhibitors and other auxiliary additives or mixtures of two or more of these. Specific examples of these additives will be described below.

Examples of the oiliness improver include oils such as rapeseed oil, higher fatty acids such as oleic acid,
Examples thereof include fatty acid esters such as methyl ester of rice bran oil.

Examples of the extreme pressure additive include chlorine-containing compounds such as chlorinated paraffin, sulfurized fats and oils, polysulfide and zinc dithiophosphide (ZnDT).
P) etc. are illustrated.

Examples of the rust inhibitor include calcium or barium organic sulfonate.

Examples of other auxiliary additives include anticorrosion agents such as benzotriazole.

Further, in the present invention, a petroleum hydrocarbon oil may be mixed and used with the organic carbonate as a base material. Isoparaffinic hydrocarbon oil, which is one of them, is substantially composed of butene, an aliphatic saturated hydrocarbon obtained by polymerizing butylene fraction,
It is colorless and transparent and odorless. Such isoparaffinic hydrocarbon oils have been recently developed and their uses are for the production of articles for food processing, processing, packaging, preservation, vegetable cleaning agents, fruit and vegetable film coating ingredients, It is widely used as a compounding ingredient for various solvents, defoamers or agricultural chemicals. In addition, the use as a base material (base oil) of a lubricating oil that requires low-temperature characteristics due to its low pour point has also been developed.

It is preferable to use this petroleum hydrocarbon oil after blending it with an organic carbonate because the lubricity is further improved. The isoparaffinic hydrocarbon oil has a flash point of 40 ° C. or higher, preferably 70 ° C. or higher, and a normal pressure boiling point of 300 ° C. or lower, preferably 100 to 100 ° C.
Those in the range of 260 ° C. are advantageous in terms of the volatilization rate described later.

As the petroleum hydrocarbon oil, those having the above-mentioned properties are commercially available and can be used as they are.

When a petroleum hydrocarbon oil is used, its blending ratio is 1 to 95% by weight, preferably 5 to 70% by weight.

In addition to the above-mentioned organic carbonates, additives and petroleum hydrocarbon oils, the lubricating oil for press working of the present invention includes other additives added to the lubricating oil (for example, stabilizers,
A surfactant or the like) may be added as it is according to the purpose.

Further, the lubricating oil of the present invention may be blended with a conventionally known lubricating oil in a small proportion as long as it does not interfere. The blending ratio is 10% by weight or less. Known lubricating oils that can be blended include fats and oils (eg rapeseed oil), fatty acids (eg oleic acid), fatty acid esters (eg rice bran oil methyl ester), chlorinated paraffins, sulfurized oils and fats,
Examples thereof include polysulfide and metal sulfonate.

[0036]

EXAMPLES The present invention will be described below with reference to examples. Also, the production examples are examples for synthesizing the organic carbonates used in the examples. In addition, in the blending ratio, "%" means "% by weight". Production examples of some organic carbonate compounds will be described.

Production Example 1 Di (n-butyl) carbonate (DNBC) 2,525 g (34) of n-butanol was placed in a reaction flask of 5 liter capacity equipped with a sieve tray type distillation column (10 plates).
Mol), dimethyl carbonate (DMC) 1,535 g
(17 mol) and 3.3 g of a 28% solution of sodium methylate in methanol were charged. Then, this mixture is stirred, operating pressure: normal pressure to 28 mmHg, operating temperature: 8
The mixture was heated at 3 to 142 ° C. for 20 hours, during which methanol, methyl (n-butyl) carbonate and excess DMC produced as by-products were distilled off, and the reaction product was collected in a flask. The catalyst was removed by adding water and / or a neutralizing agent to the reaction product thus obtained. After that,
The reaction product was distilled off under reduced pressure (18 mmHg) at a distillation temperature of 95 ° C. to isolate 2,233 g of product di (n-butyl) carbonate. As a result of analyzing the obtained fraction by gas chromatography, the purity of di (n-butyl) carbonate was 99.9%.

Production Example 2 Methylheptyl carbonate (MHPC) In a reaction flask of 3 liter capacity equipped with a sieve tray type distillation column (10 plates), 509 g of heptanol (4.4 mol), 2,333 g of DMC (26 mol) and sodium methylate. 18.0 g of a 28% methanol solution of was added. Then, this mixture is stirred and operating pressure: normal pressure,
Operating temperature: heated under conditions of 90 to 100 ° C. for 6 hours, during which methanol by-produced and excess DMC were distilled off, and a reaction product was collected in a flask. After removing the catalyst from the reaction product thus obtained, the unreacted D
Under reduced pressure (160 mmH) to remove MC and heptanol and finally obtain the product methylheptyl carbonate.
g), the reaction product is separated by distillation at a distillation temperature of 150 ° C.,
555 g of product was isolated. As a result of analyzing the obtained fraction by gas chromatography, the purity of methylheptyl carbonate was 99%.

Production Example 3 Methyl n-octyl carbonate (MNOC) In a reaction flask having a capacity of 3 liters equipped with a sieve tray distillation column (10 plates), 520.0 g of n-octanol, D was added.
MC, 216.0 g and 17.7 g of a methanol solution containing 28% by weight sodium methylate were charged. Then, the mixture is heated to 90 to 100 ° C. under normal pressure,
The reaction was carried out for 6 hours. Water was added to the reaction mixture thus obtained to remove the catalyst, and then unreacted DMC was distilled off to obtain methyl n-octyl carbonate 527.0.
g was isolated by distillation. The obtained methyl n-octyl carbonate was analyzed by GC and found to have a purity of 98%.
Met.

Production Example 4 Methyl n-dodecyl carbonate (MDDC) Methyl n-dodecyl carbonate 561.4 g was prepared in the same manner as in Production Example 3 except that n-dodecanol 744.0 g was used in place of n-octanol. Was isolated by distillation. The obtained methyl n-dodecyl carbonate was analyzed by GC, and as a result, the purity was 98%.

Production Examples 5-9 Instead of n-butanol of Production Example 1, ethanol (Production Example 5), isopropanol (Production Example 6), n-propanol (Production Example 7), isobutanol (Production Example 8) or The reaction was performed in the same manner except that heptanol (Production Example 9) was used, and diethyl carbonate (DEC), diisopropyl carbonate (DIPC), di-n-propyl carbonate (DNPC), diisobutyl carbonate (DIBC) or diheptyl carbonate was used. (DHP
C) were obtained respectively. The purity of the obtained carbonate was 95% as a result of gas chromatography analysis.
That was all.

Production Example 10 Di (methoxypropyl) carbonate (DMPC) 1,674 g of methoxypropanol was placed in a reaction flask of 5 liter capacity equipped with a sieve tray distillation column (10 plates).
(18.6 mol), 835 g of dimethyl carbonate (9.
3 mol) and 8.9 g of a 28% solution of sodium methylate in methanol. Then, this mixture is heated under stirring under the conditions of operating pressure and operating temperature of atmospheric pressure and 93 to 137 ° C. for 14.5 hours, during which methanol and excess low boiling point components such as dimethyl carbonate are distilled off. ,
The reaction product was collected in a flask. The catalyst was removed by adding water and / or a neutralizing agent to the reaction product thus obtained. Then, the reaction product is separated by distillation while the pressure is gradually reduced to 3 mmHg (final distillation temperature 125 ° C).
Product, 861 g of di (methoxypropyl) carbonate
Was isolated. As a result of analyzing the obtained fraction by gas chromatography, the purity of di (methoxypropyl) carbonate was 99% or more.

Example 1 (Lubricity Test) It is difficult to quantitatively evaluate the lubricity of the lubricating oil for press working by actual press working of a metal plate or a direct method corresponding thereto. Therefore, the load bearing capacity, which is an indirect quantitative evaluation method as is generally used, was used as a standard for evaluating the lubricating oil. The load-bearing capacity is the maximum load that can be supported by the lubricating oil without causing seizure on the sliding friction contact surface and other damage under the constant friction conditions of the specified tester. Among the several load carrying capacity tests, the load carrying capacity was investigated according to the Soda standard method of the four-ball system, which is the most commonly used for testing metalworking oils.

The base materials used in the test were various organic carbonates and isoparaffinic hydrocarbon oil (BASE-A or BASE) which is an example of petroleum hydrocarbon oil.
-B) is a single and / or a mixture as a comparative example. The results of these types and withstand loads are shown in Table 2.
Also used isoparaffinic hydrocarbon oil (BASE-
The properties of A or BASE-B) are shown in Table 3. The results of adding various additives to various organic carbonates are shown in Table 4.

[0045]

[Table 2]

[0046]

[Table 3]

[0047]

[Table 4]

Example 2 (Volatilization test) In order to satisfy the requirement for eliminating the degreasing step after press working, most of the lubricating oil remaining on the worked metal plate after press working volatilized and disappeared. There must be. In addition, a shorter volatilization time is often preferred. As a guide, it is preferable that the test is conducted within 1,500 minutes under the same conditions. Therefore, the volatility (volatilization rate) of the organic carbonate is important. 100 mm x 2 as the evaluation method
0.5 g of the organic carbonate shown in the following Table 5 was evenly applied to the surface of a 00 mm x 1.0 t SPC material (cold rolled steel sheet), and the mixture was applied under room temperature conditions (1 atm, 20 to 40 ° C, 50 to 70%).
The time until complete volatilization in HR) was examined. The results are shown in Table 5 below.

[0049]

[Table 5]

[0050]

EFFECT OF THE INVENTION The lubricating oil of the present invention volatilizes with little or no residue at room temperature and atmospheric pressure, and has a good lubricity by itself, so that friction and burning of tools such as molds can be avoided. It has become possible to reduce the degreasing load or provide a lubricating oil for press work that does not require degreasing. Organic carbonates have a lower boiling point and a higher flash point than petroleum hydrocarbon oils having the same molecular weight, and are therefore easy to handle.

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI C10M 105: 48 C10M 105: 54 105: 54) C10N 20:00 A C10N 20:00 30:00 Z 30:00 30:06 30 : 06 40:24 Z 40:24 (72) Inventor Ken Fujii 2-7 Toranomon, Minato-ku, Tokyo Within Mitex Co., Ltd. (72) Inventor Hugo Romano Bierbench Quint Aprile, Bimercate, Italy 10 (72) Inventor Franco Rivetci 41, Via Capitano Giuseppe Serra, City of Sio, Italy (72) Inventor Takeshi Hayashi 6-2 Waki, Waki-cho, Koku-gun, Yamaguchi Mitsui Petrochemical Industry Co., Ltd. ( 56) References JP-A-2-296898 (JP, A) JP-A-3-149295 (JP, A) JP-A-61-26695 (JP, A) JP-A-61-185600 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) C10M 105/48 C10M 101/02 C10M 105/54 C10M 111/02 C10N 20:00 C10N 30:00 C10N 30:06 C10N 40:24

Claims (4)

(57) [Claims] 1. A flash point of 30 ° C. or higher and a boiling point under atmospheric pressure of 265 ° C. or lower, and the following formula (I) : In the formula, a and b independently represent an integer of 1 to 6, and x and
And y independently represent 0 or 1. Also, R ¹ and
R ² is independently an alkyl group having 30 or less carbon atoms,
Alkyl group, alkylphenyl group, benzyl group or
An alkylbenzyl group is shown, and the alkyl moiety in each group
May be linear or branched, and the alkyl moiety
The hydrogen atom in is replaced with a chlorine atom or a fluorine atom.
A lubricating oil for pressing, which contains an organic carbonate represented by: 2. The lubricating oil according to claim 1, wherein the organic carbonate has a boiling point under normal pressure in the range of 100 to 250 ° C. 3. The lubricating oil according to claim 1, containing 5% by weight or more of the organic carbonate. 4. A petroleum hydrocarbon oil having a flash point of 40 ° C. or higher and a boiling point under atmospheric pressure of 300 ° C. or lower, 1 to 95.
The lubricating oil according to claim 1, wherein the lubricating oil is contained in a weight percentage.