JPS6050396B2 - Base oils and compositions for metal lubrication - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to lubricating oil compositions suitable for and for the lubrication of metals.

More specifically, the present invention relates to a lubricating oil composition for metals and metal lubrication having good heat resistance. Lubricating oils made of oxyalkylene compounds have various advantages, such as not generating sludge, not attacking rubber or metals, having a relatively high flash point, having a large viscosity index, being water-soluble, and having low toxicity. However, it has poor heat resistance and is prone to oxidation and decomposition at high temperatures.

For this reason, various antioxidants are added to improve heat resistance depending on the application, but the effect is not sufficient.
When used at high temperatures, the oxyalkylene compound decomposes in a short time and loses its effectiveness as a lubricant. The inventors of the present invention have conducted intensive studies to solve this drawback, and as a result, have arrived at the present invention.

That is, the present invention provides a heat-resistant oxyalkylene ether having a molecular weight of 400 to 2,000 and containing an oxyalkylene ether in the form of an alkylene oxide added to the hydroxyl group of bisphenols (hereinafter simply referred to as oxyalkylene ether of bisphenols). Good non-aqueous type for metal lubrication with good properties (first invention), and molecular weight of 400 to 200.
This is a lubricating composition for metal lubrication having good heat resistance (second invention), characterized in that the composition contains at least 20% by weight of oxyalkylene ether of bisphenols (2nd invention). In the present invention, bisphenols have the following general formula H〇-Y0-OH (1) (wherein, Y is an alkylene group having 1 to 5 carbon atoms,
It is a divalent organic group selected from the group consisting of a fluorine-substituted alkylene group of 5 and -500.

). Specifically, bisphenol A
[2,2-bis(4-hydroxyphenyl)propane]
, bisphenol B [2,2-bis(4-hydroxyphenyl)butane], bisphenol F [bis(4-hydroxyphenyl)methane], bisphenol S [bis(
4-hydroxyphenyl)sulfone], and 2,2-
Bis(4-hydroxyphenyl)hexafluoropropane is mentioned.

Among these, bisphenol A and bisphenol B are preferred. In the oxyalkylene ether of bisphenols in the present invention, the oxyalkylene groups constituting the oxyalkylene ether include oxyalkylene groups such as oxyethylene, oxypropylene, and oxybutylene, substituted oxyalkylene groups such as oxystyrene, and Two or more of these groups may be used.

This oxyalkylene ether can be obtained by adding alkylene oxide to the above-mentioned bisphenols.

As alkylene oxide, ethylene oxide (E
O), propylene oxide (PO), 1,2-,2,
Examples include 3-,1,3-butylene oxide, tetrahydrofuran, styrene oxide, and two or more thereof. Preferred among alkylene oxides are:
Since it is easier to handle this oxyalkylene ether when it is liquid at room temperature, PO and EP. (It is used in combination with 5P0. In the case of a combination system with EO.5PO, the PO content (weight) in the alkylene oxide is usually 20:% or more, preferably 30%, since it is preferably liquid over a wide temperature range. % or more. Also, depending on the application, it may be necessary for the oxyalkylene ether to be water-soluble.
In this case, the EO content (weight) in alkylene oxide
is usually 20% or more, preferably 30%.
When alkylene oxide is added to 3-bisphenols, catalysts (alkali catalysts, amine catalysts, acidic catalysts, etc.) are generally used.Also, when adding two or more types of alkylene oxides, either block addition or random addition is used. However, block addition is preferable.In the case of block addition, EO,
It is preferable to add them in the order of PO. The number of moles of alkylene oxide added to bisphenols is usually 2 to 2.
64, preferably 4-40. The oxyalkylene ether of bisphenols in the present invention has the following general formula (where Y is an alkylene group having 1 to 5 carbon atoms,
is a divalent organic group selected from the group consisting of a fluorine-substituted alkylene group, and -SO2fu.

Further, A is an ethylene group, a propylene group, a butylene group and/or a styrylene group. m+n is a number from 2 to 64. ) can be shown.

The molecular weight of the oxyalkylene ether of bisphenols is preferably large from the viewpoints of lubricity, low flammability, and low toxicity, but if it is too large, heat resistance will deteriorate.

Therefore, the average molecular weight is usually 400 to 2,000.
When the average molecular weight is less than 40, the proportion of hydrocarbons in the derivative increases, and carbon sludge is generated more often due to oxidative decomposition. Moreover, when it is larger than 2000, the decomposition of the polyoxyalkylene moiety becomes significant and the heat resistance decreases. In the present invention, the oxyalkylene ether of bisphenols can be used as a base oil of a lubricating oil for metal lubrication having good heat resistance.

If necessary, conventional lubricating base oils [mineral oil, animal and vegetable oils, polyoxyalkylene compounds (polyoxyalkylene mono or polyol ether), etc.] can be used in combination with the above base oil.

In this case, the content of the base oil of the present invention is usually 30 to 100%, preferably 50 to 100%, particularly preferably 70 to 100%, based on the total weight of the base oil of the present invention and conventional lubricating oil.
%. The base oil of the present invention may optionally contain a solid lubricant,
A lubricating composition can be prepared by adding optional components such as a thickener, an oiliness improver, a rust preventive, and an antioxidant.

Solid lubricants include graphite, molybdenum disulfide, tungsten disulfide, boron nitride, silicon nitride, and graphite fluoride. Preferably it is molybdenum disulfide. Thickeners include oxyalkylene ethers of high viscosity monohydric alcohols or polyhydric alcohols, such as New Ball LB-3000 (P of monohydric alcohols).
O adduct, Sanyo Chemical Products), New Ball 75H-
90,000 (dihydric alcohol EO, PO adduct product manufactured by Sanyo Chemical Industries).

Examples of oiliness improvers include carboxylic acids (furylic acid, oleic acid, dimer acid, benzoic acid, dimethylbenzoic acid, etc.) and alkali metal salts of carboxylic acids.

Rust inhibitors include amines (alkanolamine, diethylenetriamine, dicyclohexylamine, etc.), amine derivatives (alkylene oxide adducts of amines, etc.), benzotriazole, mercaptobenzothiazole, mercaptobenzimidazole, and polyhydric alcohol esters. (sorbitan monooleate, sorbitan distearate, etc.), and in some cases, it may serve both as an oiliness improver and a rust preventive agent. In addition, as antioxidants, phenol derivatives (p-Tert-butylphenol, 2,6-di-Tert-butyl-4-methylphenol, 2,2''-methylidenebis(6-Tert-butylphenol),
butyl-4-methylphenol), 4,4″-butylidenebis(6-Tert-buty-3-methylphenol), 4,4″-butylidenebis(6-Tert-butyl-3-methylphenol), tetrakis(methylene(3-methylphenol),
, 5-di-Tert-butyl-4-hydroxyhydrocinnamate)] methane, etc.) and amine derivatives [N
,N''-diphenyl-P-phenylenediamine, N,N
″-di-β-naphthyl-β-phenylenediamine, 2,
2,4-trimethyl-1,2-dihydroquinoline polymer]. By using an antioxidant in combination, heat resistance can be further improved.

The amount of solid lubricant used is usually 5% based on the weight of the composition.
% or less, preferably 3% or less, 0.1% or more (particularly 0.3% or less)
% or more).

The amount of thickener used is usually 20% based on the weight of the composition.
It is preferably 15% or less. The amount of the oiliness improver, rust preventive and antioxidant added is usually 5% or less, preferably 4% or less, of the weight of the composition. The total amount of optional components is usually 40% or less, preferably 30% or less, based on the weight of the composition. A formulation example of a slippery composition using the base oil of the present invention is as follows (% is based on weight).

Lubricant base oil 60-100% Solid lubricant 0-5% Thickener 0-20
% Oiliness improver 0-5% Rust preventive 0-5% Antioxidant 0-5% The lubricating oil composition of the present invention preferably contains an oxyalkylene ether of bisphenols as a base oil, preferably 20%.
% or more, particularly preferably 30% or more.

If it is less than 30%, the composition will not have sufficient heat resistance.

The base oil of the present invention has significantly improved heat resistance, which has been a drawback of conventional oxyalkylene compounds.

Moreover, conventional oxyalkylene compounds have
It also has the following properties: it does not generate sludge, can be made water-soluble, has good viscosity, and has good lubricity. The base oil of the present invention is suitable as a base oil for lubricating oils for machinery and metals such as machine oil, gear oil, compressor oil, and refrigerator oil.

In particular, lubricating oil for bearings on transport carts in glass and ceramic furnaces, lubricating oil for moving mechanical parts inside and outside of blast furnaces in cement manufacturing, lubricating oil for thermal glass shearing machines, gears in heat treatment equipment,
It is extremely effective as a base oil for lubricating oils used in high-temperature environments, such as chain lubricating oils, and as a base oil for lubricating oils for low-speed, high-load bearing gears that generate local heat.
In place of the polyoxyalkylene adduct in the present invention, a polyoxyalkylene adduct of an alkyl-substituted phenol (such as that described in JP-A-52-89586) or a polyoxyalkylene adduct of a lower alkyl-substituted aryl alcohol (such as that described in JP-A-52-89586) or a polyoxyalkylene adduct of a lower alkyl-substituted aryl alcohol (such as that described in JP-A-52-89586) is used. When using a material such as that described in Publication No. 48-101384), the heat resistance is insufficient.

The present invention will be further explained below with reference to Examples, but the present invention is not limited thereto.

5 The polymers used in the examples are as follows.

Note that all average molecular weights are calculated in terms of hydroxyl value. (P-
1) Polymer a Polyoxypropylene ether of bisphenol A (average molecular weight 684, hydroxyl value 164) (P-2) Polymer b Polyoxypropylene ether of bisphenol A (average molecular weight 984, hydroxyl value 114) (P- 3) Polymer c Polyoxypropylene ether of bisphenol A (average molecular weight 1272, hydroxyl value 88) (P-4) Polymer d Polyoxypropylene ether of bisphenol A (average molecular weight 1968, hydroxyl value 57) (P-5) Polymer e Poly(oxyethylene, oxypropylene) ether of bisphenol A (average molecular weight 720, water absorption value 156)
) Note-1) Poly(oxyethylene/oxypropylene) ether of bisphenol A is bisphenol A.
A block adduct of ethylene oxide and propylene oxide.

The same description will be used below. Note-2) Ethylene oxide nipropylene oxide 20:80 weight ratio (P-6)
Polymer f Polyoxypropylene ether of bisphenol B (average molecular weight 650, hydroxyl value 177) (P-7) Polymer g Poly(oxyethylene/oxypropylene) ether of bisphenol B (average molecular weight 1520, hydroxyl value 74)
) Ethylene oxide nipropylene oxide 50:5 weight ratio (P-8) Polymer h (reference product) Polyoxyalkylene ether of trimethylolpropane (average molecular weight 310, hydroxyl value 543) (P-9) Polymer 1 ( Reference product) Polyoxypropylene ether of 3 glycerin (average molecular weight 30
00, hydroxyl value 56) (P-10) Polymer j (reference product) Polyoxypropylene ether of n-butanol
4 (Average molecular weight 1870, hydroxyl value 30) (P-11) Polymer k (reference product) Polyoxyethylene ether of sorbitol (Average molecular weight 850, hydroxyl value 397) (P-12) Polymer 1 (
Reference product) Poly(oxyethylene, oxypropylene) ether of ClO linear higher alcohol (average molecular weight 930, hydroxyl value 62) Ethylene oxide nipropylene oxide 45:
55 weight ratio (P-13) polymer m (reference product) polyoxyethylene ether of linear higher alcohol with Cl6 to 18) (average molecular weight 1100, hydroxyl value 5
1) (P-14) Polymer n (reference product) Polyoxyethylene ether of nonylphenol (average molecular weight 350
, hydroxyl value 160) (P-15) Polymer 0 (reference product) Polybutene (average molecular weight: approx. 980) (P-16) Polymer p (invention product) Poly(oxybutylene oxypropylene) ether of bisphenol A ( Average molecular weight 700, hydroxyl value 160
) 1.2 Butylene oxide Nipropylene oxide = 1
5:85 weight ratio (P-17) Polymer q (invention product) Poly(oxystyrene oxypropylene) ether of bisphenol B (average molecular weight 684, hydroxyl value 164)
) Styrene oxide nipropylene oxide 50:5
Nominal ratio (P-18) Polymer r (invention product) Polyoxypropylene ether of bisphenol S (
Average molecular weight 714, hydroxyl value 157) (P-19) Polymer s (product of the present invention) Polyoxypropylene ether of bisphenol F
(Average molecular weight 664, hydroxyl value 169) Test Example 1 (Example for evaluating heat resistance stability of polyoxyalkylene ether) Regarding polymer a-g, which is the base oil of the present invention, and conventional polymer h-0 A heat resistance test was conducted.

The results are shown in Table 1. These evaluation tests were carried out using a circulating air dryer, with each dryer having an inner diameter of 10 mm and approximately 25 y.
The average remaining percentage (weight %) and appearance of the sample were measured after precisely weighing the sample and leaving it in an open state at 250°C for 2C@.*As is clear from Table 1, this is a product of the present invention. Polymers 2 a-g have superior heat resistance compared to polymers h-o, which are reference products.

Test Example 2 (Example for evaluating the sliding performance of polyoxyalkylene ether) Polymers C, e, g, p explained above
A carbon sludge generation test was conducted for 1000 hours using a Hitachi compressor (TYPESP-5SF) on lubricating oils containing Polymer C and Q as a single component and composition lubricating oils containing Polymer C as the main component, and the results were as follows. the second
Shown in the table.

The state of sludge generation was determined by observing the oil sample with the naked eye after the end of the test. If almost no sludge was observed, it was indicated as ○, and when a considerable amount of sludge was observed, it was indicated as Δ. The amount of sludge generated was diluted to 1 liter with toluene. After filtration with a 5P filter, the weight of the residual sludge was expressed as a percentage of the sample.

Claims (1)

[Scope of Claims] 1. A non-aqueous base oil for metal lubrication with good heat resistance, characterized by containing an oxyalkylene ether having a molecular weight of 400 to 2000 and having an alkylene oxide added to the hydroxyl group of bisphenols. . 2. The base oil according to claim 1, wherein the oxyalkylene ether is oxypropylene ether, oxyethylene ether or (oxyethylene-oxypropylene) ether. 3. The base oil according to claim 2, wherein the (oxyethylene-oxypropylene) ether is a block ether of oxyethylene and oxypropylene. 4. The base oil according to any one of claims 1 to 3, wherein the bisphenol is bisphenol A or bisphenol B. 5. A metal lubrication product with good heat resistance characterized by containing 20% or more by weight of the composition as a base oil of oxyalkylene ether having a molecular weight of 400 to 2000 and in the form of adding alkylene oxide to the hydroxyl group of bisphenols. A non-aqueous lubricating oil composition.