JP2003155493A - Highly basified additive composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a highly basified additive composition which can exhibit a high lubricating property imparting effect realized by inorganic microparticles with large diameters as well as transparency and fluidity desirable for a lubricating oil additive. SOLUTION: The additive composition contains 20-80 wt.% base oil, 10-55 wt.% alkaline earth metal carbonate microparticles of a mean particle diameter of at least 100 nm and 10-50 wt.% alkaline earth metal salt of a 10-25C unsaturated fatty acid as a dispersant for the microparticles and is a transparent liquid or a transparent gel at ordinary temperature.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The overbased additive composition is used for metal working oil, engine oil, gear oil, bearing oil, compressor oil, refrigerating machine oil, sliding surface oil, rust preventive oil, grease and the like. It is an additive used in various industrial lubricating oils, and has a function of neutralizing acidic compounds produced by deterioration of lubricating base oils or additives. The present invention is not particularly limited to the use as an additive for industrial lubricating oil, but can be mainly used as an additive for industrial lubricating oil.

[0002]

2. Description of the Related Art For example, when a highly basic additive is used in a lubricating oil such as an engine oil, generally the highly basic additive does not have a sufficient effect of improving the lubricating property, and a lubricating agent such as ZnDTP improves the lubricating property. It is expected that the improved and overbased additives have functions other than lubricity, such as acid neutralization and cleaning / dispersion.

The highly basic additive has basic inorganic fine particles such as calcium carbonate dispersed in the system. Such a highly basic additive is a known production method, for example, as a supply source of inorganic components in a base oil in which a surfactant (sulfonate, fatty acid salt, etc.) as a dispersant is uniformly dissolved, for example, It can be produced by blowing carbon dioxide gas into a system in which calcium hydroxide, calcium oxide, magnesium oxide, barium oxide, etc. are present. In this method, the dispersant envelops the inorganic fine particles at the same time as the generation of the inorganic fine particles giving the base number, whereby the particles can be uniformly dispersed in the system without causing precipitation or separation.

It is known that the inorganic fine particles may exhibit a solid lubricating action at the sliding interface where lubricity is required. However, when the particle size of the inorganic fine particles is sufficiently smaller than the roughness of the sliding surface, the inorganic fine particles enter the concave portions of the surface, and the solid lubricating action cannot be exhibited. On the other hand, it is essential that the lubricating oil has excellent lubricity, and there is always a demand for lubricity superior to the lubricity that can be imparted by the current lubricants.

From these backgrounds, it has been studied to impart a lubricity imparting function to a highly basic additive which has not been expected much in imparting lubricity. For example, "Molecular additive 800" manufactured by Matsumura Oil Research Institute Co., Ltd., which is a highly basic additive, uses zinc sulfonate as a surfactant component to disperse inorganic fine particles, and zinc reacts with tribochemical reaction at sliding sites. Contributes to the development of a lubricating effect.

[0006] However, regarding the solid lubrication action by the inorganic fine particles, which is the most characteristic of the highly basic additive, it is difficult to grow (increase) the inorganic fine particles to a particle size capable of expressing the solid lubrication action. ,Also,
The grown inorganic fine particles were turbid in appearance and were restricted in use as additives for lubricating oil.

[0007]

SUMMARY OF THE INVENTION The object of the present invention is to provide a highly basic additive having a large particle size of inorganic fine particles and a high lubricity imparting effect while having the transparency and fluidity desired as an additive for lubricating oil. To provide the agent.

[0008]

The present invention has been made to solve the above problems, and the present inventors have found that, among the components constituting the highly basic additive, particularly inorganic fine particles are added to the system. As a result of earnest research on a dispersant component having a function of dispersing, by using a specific unsaturated fatty acid salt as a dispersant component, it is possible to obtain an additive composition in which fine particles having a large average particle size are transparently dispersed. In addition to the finding, they have found that when applied to a lubricant, they can effectively impart lubricity, and have completed the present invention.

That is, the present invention provides the following (a) and (b):
(C) It is an additive composition satisfying all the conditions of (d). (A) Contains 20 to 80% by weight of a base oil mainly composed of a mineral oil or a hydrocarbon compound compatible with the mineral oil. (B) 10 to 55% by weight of fine particles of an alkaline earth metal carbonate having an average particle diameter of 100 nm or more. As a dispersant for the fine particles of (c) and (b), the number of carbon atoms is 10 to 2
10 to 50% by weight of the alkaline earth metal salt of unsaturated fatty acid of No. 5 is contained. (D) Additives corresponding to the above (a), (b), and (c), which are transparent liquid or transparent gel at room temperature.

In one embodiment, the alkaline earth metal is calcium.

[0011] In another embodiment, the unsaturated fatty acid is an unsaturated fatty acid having 18 carbon atoms.

In another embodiment, the unsaturated fatty acid has 1 unsaturated bond.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The additive composition of the present invention can be manufactured according to the above-mentioned known manufacturing method. That is, in the base oil in which the alkaline earth metal salt of unsaturated fatty acid which is the dispersant is uniformly dissolved, for example, calcium hydroxide, calcium oxide, magnesium oxide, barium oxide, etc. are present as a source of inorganic content. It can be manufactured by blowing carbon dioxide gas into the system. In this method, the dispersant envelops the inorganic fine particles at the same time as the generation of the inorganic fine particles giving the base number, whereby the particles can be uniformly dispersed in the system without causing precipitation or separation.

In the present invention, by appropriately adjusting the amount of base oil, the amount of unsaturated fatty acid alkaline earth metal salt, the amount of inorganic source such as calcium hydroxide, and the amount of carbon dioxide gas to be blown, the above ( The amounts of components a), (b) and (c) can be set within the scope of the present invention. In the above-mentioned production method, a lower alcohol such as methanol may be added to the reaction system as an accelerator for forming inorganic fine particles.

As the base oil used in the present invention, a base oil mainly containing a mineral oil or a hydrocarbon compound compatible with the mineral oil is used. Any mineral oil can be used as long as it is generally used as a lubricating oil, and is not particularly limited. The hydrocarbon compound compatible with the mineral oil may be either an aromatic hydrocarbon compound or an aliphatic hydrocarbon compound. Examples of such aromatic hydrocarbon compounds include alkylbenzene, alkylnaphthalene, alkyldiphenyl ether, and the like, and examples of aliphatic hydrocarbon compounds include polyalphaolefin, liquid paraffin, and the like. The component amount of the above base oil is 20 to 80% by weight, and particularly preferably 25 to 50% by weight, based on the total amount of the additive. 20%
In the following, the additive composition becomes solid and the solubility when added to the lubricating oil becomes poor. When it is 80% or more, the solubility in lubricating oil is good, but the total base number (hereinafter abbreviated as TBN) becomes small, which impairs the performance as an additive composition. As a commercially available overbased additive in which calcium carbonate is dispersed, a product having a TBN of 300 to 500 is often used. The base oil of the highly basic additive having TBN in this range is 25 to 50% by weight, and the range of the present invention is particularly preferable.

As the alkaline earth metal carbonate of the present invention, carbonates of magnesium, barium and calcium can be used, but calcium carbonate is most preferable mainly from the economical aspect. The average particle size of these fine particles needs to be 100 nm or more, preferably 300 nm or more, and most preferably 2000 nm, as a particle size that can be added to lubricating oil to impart sufficient lubricity. Generally, the larger the particle size, the greater the effect of imparting lubricity, and the present invention has made it possible to obtain an additive composition containing fine particles of calcium carbonate having a particle size of 2500 nm. The average particle size as referred to in the present invention means the average particle size measured by a dynamic light scattering type particle size distribution meter and calculated by the Marquardt method. The amount of the fine particles in the additive composition is 10 to 55% by weight, preferably 15 to 45%.
% By weight.

The additive composition of the present invention contains 15 to 45% by weight of an alkaline earth metal salt of an unsaturated fatty acid having 10 to 25 carbon atoms as a dispersant for the fine particles. As the unsaturated fatty acid, an unsaturated fatty acid having 10 to 25 carbon atoms can be used, and an unsaturated fatty acid having 18 carbon atoms is preferable. If the number of carbon atoms is more or less than this range, the dispersibility of the fine particles becomes poor. As a result, above
The particle size of the alkaline earth metal carbonate does not become sufficiently large. The number of unsaturated bonds of the unsaturated fatty acid is not particularly limited, but is preferably 1. Such unsaturated fatty acids include oleic acid (C18 ', unsaturated bond number 1), erucic acid (C22', unsaturated bond number 1), linoleic acid (C18 '', unsaturated bond number 2), linolenic acid. Acid (C
18 ″ ′, the number of unsaturated bonds 3) and the like can be mentioned, but oleic acid is most preferably used. These unsaturated fatty acids may be used alone or as a mixture. When the unsaturated fatty acid having 10 to 25 carbon atoms is not used, the additive composition of the present invention cannot be obtained. For example,
When a saturated fatty acid is used alone, the entire additive solidifies and a transparent solution or gel-like substance cannot be obtained. However, the combined use of saturated fatty acids and the above unsaturated fatty acids is not excluded, and mixed fatty acids of unsaturated fatty acids and saturated fatty acids do not hinder the practice of the present invention. Further, sulfonic acid and unsaturated fatty acid may be used in combination. When sulfonic acid is used alone, a transparent additive can be obtained, but its particle size does not become sufficiently large. However, sulfonic acid and carbon number 10-25
The additive composition of the present invention can be obtained by using the unsaturated fatty acid in combination.

Examples of the alkaline earth metal salts of these unsaturated fatty acids include metal salts of magnesium, barium, calcium and the like. Generally, a salt of the same metal as the carbonate of the fine particles is usually used. And a calcium salt is most preferably used. The content of these alkaline earth metal salts of unsaturated fatty acids needs to be 10 to 50% by weight, preferably 15 to 45% by weight, based on the total amount of the additive composition. When the unsaturated fatty acid alone is less than 10%, or when it is used together with the saturated fatty acid and the unsaturated fatty acid is less than 10%, a sufficient dispersing effect cannot be obtained, and the solubility in the base oil is deteriorated. When unsaturated fatty acid is less than 10% in combination with sulfonic acid,
The solubility in base oil is good, but the particle size of fine particles is 10
Those having a thickness exceeding 0 nm cannot be obtained. If it exceeds 50%, the TBN tends to be small and the performance as an additive composition is impaired.

Thus, an additive composition containing the above-mentioned base oil, fine particles of alkaline earth metal carbonate, and an alkaline earth metal salt of unsaturated fatty acid as a dispersant for the fine particles is obtained. When the TBN of the additive composition of the present invention is measured, the values due to the alkaline earth metal carbonate and the fatty acid alkaline earth metal salt are measured in the form of addition. When the TBN attributable to each of them is calculated from the content, the TBN attributed to the alkaline earth metal carbonate is 110 to 620, and the TBN attributed to the fatty acid alkaline earth metal salt is 20 to 100.
Becomes Therefore, the TBN of the additive composition is 130
It becomes the range of -720, and 190-580 are more preferable.

The additive composition of the present invention needs to have a transparent solution or gel appearance at room temperature. When it is opaque even if it is solid, solution or gel, when it is used as a lubricating oil additive, it does not dissolve well in a lubricating base oil such as mineral oil, or an alkaline earth metal carbonate. Is not practically usable as an additive composition.

The amount of the additive composition used in the present invention varies depending on the use of the lubricating oil, but is generally 0.1 to 0.1% in the lubricating oil.
It is added at a concentration of 80% by weight, preferably 1-50% by weight. The compositions of the present invention can be used alone in lubricating oils, but are generally used with various other additives. Typical of such an additive is an oiliness agent for enhancing the lubricating effect if it is a metal working oil, a sulfur-based additive, a phosphorus-based additive, a chlorine-based additive, an organometallic additive,
There are surfactants and the like for use in an aqueous system. In the case of engine oil, there are viscosity index improvers, detergent dispersants and the like. In the case of grease, there are thickeners and the like.

Examples of the oiliness agent include vegetable oils such as palm oil and rapeseed oil, animal oils such as beef tallow and lard, fatty acids obtained from these oils and fats, and esters obtained by reacting these fatty acids with various alcohols. To be Examples of the sulfur-based additive include sulfurized fats and oils, sulfurized fatty acids, polysulfides, and the like. Examples of the phosphorus-based additive include phosphoric acid ester and acidic phosphoric acid ester. Examples of the chlorine-based additive include chlorinated paraffin and chlorinated fatty acid. Examples of the organometallic additive include dialkyldithiophosphoric acid,
Examples thereof include metal salts with zinc, molybdenum, lead and the like such as dialkyldithiocarbamic acid and naphthenic acid.

Examples of the surfactant include nonionic surfactants such as polyoxyethylene-based and polyhydric alcohol-based surfactants, fatty acid derivatives and sulfates, and anionic-based surfactants such as sulfonic acid-based surfactants. Examples of the viscosity index improver include polymethacrylate, polyisobutylene, olefin-based copolymer, polyalkylstyrene and the like. Examples of the detergent dispersant include metal salt type detergent dispersants such as neutral and basic sulfonates, neutral and basic phenates, succinimide type, benzylamine type, and methacrylate copolymers containing N-vinylpyrrolidinone. Ashless detergent dispersants such as These additives can be used in the amounts generally used unless they impair the performance of the present invention. Among the detergent dispersants used for engine oils, there are metal-based detergent dispersants having an excellent acid neutralizing action, and the composition of the present invention can also be used for that purpose. Examples of the thickener include metal soaps such as lithium, sodium, aluminum and calcium or composite metal soaps, non-soap based such as silica gel, bentone, urea compounds and urethane compounds.

[0024]

EXAMPLES The present invention will be described in more detail with reference to the following examples and comparative examples, but the invention is not limited thereto.

(1) Preparation of Additive Composition Example 1 248.0 g of commercial industrial oleic acid (unsaturated fatty acid content 92%, oleic acid content 74%), refined mineral oil 265.0
g, toluene 590.0 g, methanol 82.0 g,
The mixture was placed in a 3 liter four-necked flask equipped with a reflux condenser, a thermometer, a carbon dioxide gas inlet tube, and a stirrer, and mixed and dissolved. To this, 37.0 g of calcium hydroxide and 6.5 g of water were added to neutralize fatty acids to form calcium soap, and then water was removed by heating. Then add 1 more of calcium hydroxide
87.0g was added and it installed in the 40 degreeC-50 degreeC water bath. After mixing with a stirring blade, carbon dioxide gas was bubbled through the carbon dioxide gas introduction tube at a flow rate of 470 ml / min for 100 minutes. Next, the reaction mixture was heated to 120 ° C., water in the system was removed, and then cooled to room temperature. A filter aid was added to the obtained reaction mixture and mixed, and the mixture was filtered under pressure to separate a filtrate and a filter layer. Volatile substances were removed from the filtrate by a thin film evaporator to obtain 398.0 g of a clear gel-like composition containing fine particles of calcium carbonate. The fatty acid calcium salt content of the obtained composition was 36.6% by weight, and the calcium carbonate content was 26.8% by weight.

Example 2 The same treatment as in Example 1 was carried out except that the amount of calcium hydroxide added was changed to 79.0 g and the flow rate of carbon dioxide gas was changed to 220 ml / min, and bubbling was carried out for 90 minutes, and fine particles of calcium carbonate were contained. 563.0 g of a clear oily composition was obtained. The fatty acid calcium salt content of the obtained composition was 42.0% by weight, and the calcium carbonate content was 15.9% by weight.

Example 3 215.0 g of commercially available industrial fatty acid containing oleic acid (unsaturated fatty acid content 93%, oleic acid content 43%), refined mineral oil 230.0 g, toluene 1200.0 g, methanol 71.0 g Was placed in a 3 liter four-necked flask equipped with a reflux condenser, a thermometer, a carbon dioxide gas inlet tube, and a stirrer to mix and dissolve. 31.0 g of calcium hydroxide,
After adding 5.5 g of water to neutralize the fatty acids to form calcium soap, the water was removed by heating. Next, 358.0 g of calcium hydroxide was added, and the mixture was placed in a water bath at 40 ° C to 50 ° C. After mixing with a stirring blade, carbon dioxide gas was bubbled through the carbon dioxide gas introduction tube at a flow rate of 81 ml / min for 110 minutes. Then, the same treatment as in Example 1 was carried out to obtain 698.0 g of a clear gel composition containing fine particles of calcium carbonate. The fatty acid calcium salt content of the obtained composition was 29.6% by weight, and the calcium carbonate content was 40.8% by weight.

Example 4 Commercially available industrial oleic acid 169.0 used in Example 1
g was mixed with 114.0 g of commercial industrial isostearic acid to prepare a fatty acid having an unsaturated fatty acid content of 55% and an oleic acid content of 45%. This mixture was treated in the same manner as in Example 1 except that the commercial industrial oleic acid used in Example 1 was used to obtain 784.0 g of a clear oily composition containing fine particles of calcium carbonate. The fatty acid calcium salt content of the obtained composition was 35.8% by weight, and the calcium carbonate content was 28.3% by weight.

Example 5 Commercially available industrial oleic acid used in Example 1 was used as 125.
0 g, refined mineral oil 104.0 g, toluene 770.0 g,
42.0 g of methanol was placed in a 2 liter four-necked flask equipped with a reflux condenser, a thermometer, a carbon dioxide gas introduction tube, and a stirrer, and mixed and dissolved. Calcium hydroxide 18.
After adding 0 g and 3.3 g of water to neutralize the fatty acids to form calcium soap, the water was removed by heating. Next, 144.0 g of calcium hydroxide was further added, and the temperature was 40 ° C to 5 ° C.
It was placed in a water bath at 0 ° C. After mixing with a stirring blade, carbon dioxide gas was bubbled through the carbon dioxide gas introduction tube at a flow rate of 314 ml / min for 114 minutes. Here, after adding 298.0 g of calcium sulfonate Ca-45N manufactured by Matsumura Oil Research Institute, the reaction mixture was heated to 120 ° C., water in the system was removed, and then cooled to room temperature. Thereafter, the same treatment as in Example 1 was carried out to obtain 602.0 g of a clear oily composition containing fine particles of calcium carbonate. The composition obtained had a fatty acid calcium salt content of 19.1% by weight, a calcium sulfonate content of 19.1% by weight, and a calcium carbonate content of 23.4% by weight.

Comparative Example 1 The same procedure as in Example 1 was carried out except that all the commercially available industrial oleic acid used in Example 1 was replaced with the commercially available industrial isostearic acid described in Example 4. After the bubbling of carbon dioxide gas, calcium carbonate was deposited and precipitated, and the intended product could not be obtained.

Comparative Example 2 In a 5 liter four-necked flask equipped with a reflux condenser, a thermometer, and a carbon dioxide gas introduction tube, 700.0 g of calcium sulfonate Ca-45N manufactured by Matsumura Oil Research Institute, and toluene 140 were added.
0.0 g, mineral oil 88.0 g, methanol 175.0 g,
Put calcium hydroxide 285.0g, 40 ℃ ~ 50 ℃
It was installed in the water bath. Carbon dioxide gas was bubbled through the carbon dioxide gas introduction tube at a flow rate of 855 ml / min for 80 minutes while stirring. Then, the same operation as in Example 1 was performed to obtain 910.0 g of a clear composition. The composition obtained had an oil-soluble calcium sulfonate content of 28.5% by weight and a calcium carbonate content of 24.0% by weight.

Comparative Example 3 Commercially available overbased calcium sulfonate (manufactured by Lubrizol: 5347) was used as a commercial product A.

(2) Particle size measurement of inorganic fine particles in the additive composition To measure the particle size of the fine particles dispersed in the additive composition, toluene filtered through a 0.1 μm (100 nm) membrane filter was used. Each additive was dissolved to a concentration of 10% by weight, the particle size distribution of the inorganic particles was measured using a dynamic light scattering particle size distribution measuring device DLS-6000 manufactured by Otsuka Electronics, and the average particle size was calculated. .

(3) Lubricity test Each additive was dissolved in refined mineral oil in an amount of 5% by weight, and AS was used using a Falex Pin / Vee tester manufactured by Shinko Seiki Co., Ltd.
The seizure load was measured according to the method described in TM D-3233.

(4) TBN (total base number) measurement The total base number of the additive composition was measured according to JIS K-2501 (perchloric acid method). When measured by this method, the fatty acid metal salt is also measured as TBN in the additive composition containing the fatty acid metal salt. Therefore, the TBN of the additive composition containing the fatty acid metal salt is the total value of calcium carbonate and the fatty acid metal salt.

(5) Solubility in base oil For each additive composition, the same sample as in the lubricity test was prepared, and the solubility / insolubility was visually confirmed.

Table 1 shows the results obtained by measuring the items (2) to (5) of the additive compositions of Examples and Comparative Examples.

[0038]

[Table 1]

The additive compositions obtained in Examples 1 to 5 using unsaturated fatty acids all had an average particle size of 300 nm or more, although the appearance was transparent. for,
In Comparative Example 1 in which only saturated fatty acids were used, calcium carbonate could not be incorporated into the oil, and the target product could not be obtained. In addition, Comparative Example 2 using only sulfonate,
An additive composition having a transparent appearance was obtained, but the average particle size was 10 nm. Further, Comparative Example 3 which is a commercial product is also a sulfonate having a transparent appearance, but its particle size was as small as 37 nm. From the results of the lubricity test, it can be seen that Examples 1 to 5 exhibited a higher seizure load as compared with Comparative Example 2, and thus have excellent lubricity.

[0040]

INDUSTRIAL APPLICABILITY The additive composition of the present invention has a transparent appearance and is stable even when added to mineral oil or the like without causing precipitation of fine particles of carbonate of an alkaline earth metal (eg calcium carbonate). In addition, the fine particles have a large particle size, and when added to a lubricating base oil, excellent lubricity can be imparted.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C10M 125/10 C10M 125/10 129/40 129/40 // C10N 10:04 C10N 10:04 20:00 20:00 Z 20:06 20:06 Z 30:04 30:04 40:00 40:00 Z 40:02 40:02 40:04 40:04 40:20 40:20 40:25 40:25 40: 30 40:30 50:10 50:10 (72) Inventor Akihiko Konan 5-5-3 Minamijima Minami-cho, Chuo-ku, Kobe-shi, Hyogo Matsumura Petroleum Research Institute Co., Ltd. (72) Inventor Minsei Akada Chuo-ku, Kobe-shi, Hyogo Minatomachi 5-5-3 Matsumura Oil Research Institute Co., Ltd. F-term (reference) 4H104 AA13C BA03A BA07A BB08A BB17C CA01A DA02A EA01Z EA21C EA22Z FA02 LA02 PA01 PA02 PA20 PA21 PA41 PA50 QA18

Claims (4)

[Claims] 1. An additive composition satisfying all the following conditions (a), (b), (c) and (d): (A) Contains 20 to 80% by weight of a base oil mainly composed of a mineral oil or a hydrocarbon compound compatible with the mineral oil. (B) 10 to 55% by weight of fine particles of an alkaline earth metal carbonate having an average particle diameter of 100 nm or more. As a dispersant for the fine particles of (c) and (b), the number of carbon atoms is 10 to 2
10 to 50% by weight of the alkaline earth metal salt of unsaturated fatty acid of No. 5 is contained. (D) Additives corresponding to the above (a), (b), and (c), which are transparent liquid or transparent gel at room temperature. 2. The additive composition according to claim 1, wherein the alkaline earth metal is calcium. 3. The additive composition according to claim 1, wherein the unsaturated fatty acid has 18 carbon atoms. 4. The additive composition according to claim 1, wherein the unsaturated fatty acid has one unsaturated bond.