201241169 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種具有低揮發性且低溫流動性佳之特 長’並且在低溫至高溫之寬廣區域中可長時間顯現出潤滑 性之潤滑油基油以及使用該潤滑油基油之潤滑油組成物。 【先前技術】 對於潤滑油基油，係要求可長期間安定地發揮性能， 亦即低揮發性、較佳的熱及氧化安定性或低溫始動性（低 溫流動性）、高黏度指數（寬廣範圍）。尤其是具有低黏 度且爲低揮發性之特長者，說其爲終極目標一點也不爲過 0 伴隨著AV及OA機器的高性能化，對於此等的旋轉 部所使用之小型主軸馬達，係強烈要求高速化、省電化， 因此’旋轉支撐部所使用之軸承，係存在有低扭矩化之要 求。此外’近來尤其考量到對可攜式機器之應用，係要求 可應用於各種環境（溫度）之性能。影響軸承的扭矩之因 素，有軸承間隙、軸徑等，尤其在低溫環境下，潤滑油的 黏度乃成爲一大因素。 潤滑油，一般有黏度愈低愈容易蒸發之傾向。當潤滑 油因蒸發等而減少時，無法得到適當的油膜壓力，使旋轉 精度顯著降低而被視爲對壽命有所影響，因此，潤滑油的 蒸發特性爲影響軸承的耐久性之重要特性。因此，在流體 動壓軸承、多孔質含油軸承、動壓型多孔質含油軸承等之 -5- 201241169 滑動軸承的潤滑中，必須選擇低黏度且即使在低溫區亦不 會有極端的黏度上升，蒸發特性相對較佳之潤滑油。較多 情況下，係使用酯系的潤滑油》 酯油中，與其他潤滑油相同，隨著黏度愈低，蒸發特 性亦有劣化之傾向》因此，若爲了降低軸承的扭矩而僅選 擇較目前更低黏度的酯油者，則會損及蒸發特性，使軸承 的耐久性降低。此外，即使常溫下爲低黏度，若在低溫區 黏度急遽上升而失去流動性，則會導致急遽的扭矩上升或 機器的停止運轉》 尤其是近年來隨著硬碟裝載於家電中，在低溫下使用 之情況亦逐漸增多，在此假定下，爲了確保安定驅動，係 強烈要求低溫區中的低黏性。至目前爲止已提出許多滿足 此等性質之潤滑油基油，但雖然在某些領域已達滿足，但 目前在作爲終極目標之低黏度且爲低揮發性之領域中仍未 達滿足》 同時得到低黏度與低揮發性者，其相反面向較強，例 如同一結構下達到低黏度化時，其分子量會降低，當然使 揮發性增大。用以解決此般缺點之手段，係使用低黏度且 蒸發特性相對較佳之酯系的基油。 專利文獻1中，係揭示一種將由碳數6〜12的直鏈狀 二價醇與碳數6〜12的分枝鏈狀飽和一價脂肪酸所得之二 酯用作爲基油之潤滑油組成物。 然而，上述以往技術中，雖可藉由適當地選擇醇與脂 肪酸得到具有低黏度特性之潤滑油，但在40 t時的黏度 201241169 爲1 0mm2/s以下之二酯中，伴隨著低分子量化使蒸發量增 多，且由於分子量均一，使蒸發幾乎同時產生，所以有時 耐久性以一定條件下爲交界而急遽降低。該原因是由於多 數的酯具有左右對稱的化學結構之故。亦即，正因其爲單 一組成物，該臨限點爲明確，故有時仍會產生因蒸發所導 致之馬達的急速停止。 專利文獻2中，係揭示一種以由碳數8的一價醇與碳 數6的二價羧酸所合成之酯作爲主成分，並含有l~5wt% 之與該主成分不同的二酯，其係在4〇°C時的動黏度爲 1 0mm2/s以上且分子的總碳數爲23〜28之二酯之潤滑油組 成物，以及使用該潤滑油組成物之流體軸承單元。 專利文獻3中，係揭示一種含有由碳數9以下的2價 或3價羧酸與碳數3~25的伸烷二醇單烷醚等之1價二醇 醚所合成之二酯體或三酯體作爲主成分之潤滑油基油。 然而，此等文獻所記載之潤滑油或潤滑油基油’可說 是仍無法充分滿足低黏度且爲低揮發性之期望。 [先前技術文獻] [專利文獻1]日本特開2008-69234號公報 [專利文獻2]日本特開2007-39496號公報 [專利文獻3]日本WO 2007/116725號公報 【發明內容】 本發明係鑒於上述課題而創作出之發明’目的在於提 201241169 供一種具有低揮發性且低溫流動性佳之特長，並且在低溫 至高溫之寬廣區域中可長時間顯現出潤滑性之潤滑油基油 以及使用該潤滑油基油之潤滑油組成物。 本發明係關於一種潤滑油基油，其特徵係以由下列式 (1)表示之二酯爲主成分， 【化1】201241169 VI. Description of the Invention: [Technical Field] The present invention relates to a lubricating base oil which has a low volatility and excellent low-temperature fluidity and which exhibits lubricity for a long period of time in a wide region from low temperature to high temperature. And a lubricating oil composition using the lubricating base oil. [Prior Art] For lubricating base oils, it is required to perform stably for a long period of time, that is, low volatility, better heat and oxidation stability or low temperature startability (low temperature fluidity), high viscosity index (wide range) ). In particular, those who have low viscosity and low volatility are not the least in the ultimate goal. With the high performance of AV and OA equipment, the small spindle motors used in these rotating parts are There is a strong demand for high speed and power saving. Therefore, the bearings used in the rotary support have a low torque requirement. In addition, the application of portable machines has recently been considered, and the requirements are applicable to various environments (temperatures). The factors affecting the torque of the bearing are bearing clearance, shaft diameter, etc. Especially in low temperature environments, the viscosity of the lubricating oil is a major factor. Lubricating oils generally have a tendency to evaporate as the viscosity is lower. When the lubricating oil is reduced by evaporation or the like, an appropriate oil film pressure cannot be obtained, and the rotation accuracy is remarkably lowered to be considered as an effect on the life. Therefore, the evaporation characteristics of the lubricating oil are important characteristics that affect the durability of the bearing. Therefore, in the lubrication of the -5-201241169 plain bearing of fluid dynamic pressure bearing, porous oil-impregnated bearing, dynamic-pressure type porous oil-impregnated bearing, etc., it is necessary to select a low viscosity and there is no extreme viscosity increase even in a low temperature zone. A lubricating oil having relatively good evaporation characteristics. In many cases, the use of ester-based lubricants is the same as other lubricants. As the viscosity decreases, the evaporation characteristics tend to deteriorate. Therefore, if you want to reduce the torque of the bearing, only choose the current one. Lower viscosity ester oils will degrade the evaporation characteristics and reduce the durability of the bearing. In addition, even if the viscosity is low at normal temperature, if the viscosity rises rapidly in the low temperature zone and the fluidity is lost, the rapid torque rises or the machine stops. Especially in recent years, as the hard disk is loaded in the home appliance, at low temperatures. The use is also gradually increasing. Under this assumption, in order to ensure a stable drive, the low viscosity in the low temperature region is strongly required. Many lubricating base oils satisfying these properties have been proposed so far, but although they have been met in some fields, they are still not satisfied in the field of low viscosity and low volatility as the ultimate goal. For those with low viscosity and low volatility, the opposite direction is strong. For example, when the viscosity is low under the same structure, the molecular weight will decrease, and of course the volatility will increase. A means for solving such a disadvantage is to use an ester-based base oil having a low viscosity and relatively good evaporation characteristics. Patent Document 1 discloses a lubricating oil composition comprising a linear divalent alcohol having 6 to 12 carbon atoms and a diester fatty acid having a branched chain-like saturated monovalent fatty acid having 6 to 12 carbon atoms as a base oil. However, in the above prior art, a lubricating oil having a low viscosity characteristic can be obtained by appropriately selecting an alcohol and a fatty acid, but the viscosity at 40 t is 201241169, and the diester having a viscosity of 10 mm 2 /s or less is accompanied by a low molecular weight. The amount of evaporation is increased, and since the molecular weight is uniform, evaporation occurs almost simultaneously, and therefore durability may be rapidly lowered under a certain condition as a boundary. The reason for this is because most of the esters have a bilaterally symmetrical chemical structure. That is, just because it is a single composition, the threshold is clear, so there is still a sudden stop of the motor caused by evaporation. Patent Document 2 discloses that an ester synthesized from a monovalent alcohol having 8 carbon atoms and a divalent carboxylic acid having 6 carbon atoms as a main component, and containing 1 to 5 wt% of a diester different from the main component, It is a lubricating oil composition having a dynamic viscosity of 10 mm 2 /s or more and a total carbon number of the molecule of 23 to 28 at 4 ° C, and a fluid bearing unit using the lubricating oil composition. Patent Document 3 discloses a diester body synthesized from a monovalent glycol ether such as a divalent or trivalent carboxylic acid having 9 or less carbon atoms and an alkylene glycol monoalkyl ether having 3 to 25 carbon atoms or A lubricating oil base oil containing a triester body as a main component. However, the lubricating oil or lubricating base oil described in these documents can be said to be insufficiently satisfactory for low viscosity and low volatility. [PRIOR ART DOCUMENT] [Patent Document 1] Japanese Laid-Open Patent Publication No. Hei. No. 2007-39496 [Patent Document 3] Japanese Patent Publication No. 2007-39725 (Patent Document 3) Invented in view of the above-mentioned problems, the invention aims to provide a lubricating base oil which has a low volatility and good low-temperature fluidity, and which exhibits lubricity for a long period of time in a wide region from low temperature to high temperature, and uses the same. Lubricating oil base oil composition. The present invention relates to a lubricating base oil characterized by a diester represented by the following formula (1) as a main component, [Chemical Formula 1]
式中，獨立地爲1-乙基戊基、正庚基或正己 基。此外，莫耳比（A : B : C )係位於25~65 : 30〜50 : 3〜2 5之範圍內。在此，A是1及R2均爲正庚基或正己基 者，B是Ri及尺2的一者爲1-乙基戊基者，C是1^及R2 均爲1-乙基戊基者。 上述莫耳比（A : B : C )尤佳係位於35~50 : 40〜50 :5〜1 5之範圍內。 本發明之潤滑油基油，係以由式（1 )表示之二酯爲 基油的50wt%以上者爲佳。此外，本發明之潤滑油基油 ，係以含有5〜30wt%之低黏度油者爲佳，該低黏度油在 40°C時的動黏度未達9mm2/s、且係黏度指數爲100以上 並具有新戊二醇骨架之多元醇酯，該低黏度油較佳是從辛 酸或癸酸、與新戊二醇所得之多元醇酯° 此外，本發明係關於一種潤滑油組成物，其特徵係使 用上述潤滑油基油所得β -8- 201241169 【實施方式】 以下係說明本發明之實施形態。 本發明之潤滑油基油’係以由上述式（1)表示之二 酯爲主成分。較佳係含有50wt%以上之由式（1)表示之 二酯。 式（1)中，Ri、112獨立地爲1_乙基戊基、正庚基或 正己基。Ri及R2可爲相同或不同。在此，1-乙基戊基爲 分枝烷基，正庚基及正己基爲直鏈烷基。上述二酯中，R, 及R2爲來自羧酸之成分，具體而言爲來自2-乙基己酸、 辛酸或庚酸。此外，上述二酯中，來自醇之成分爲2-甲 基-1，8-辛二醇。該二酯由於不過度具有分枝鏈，所以黏度 指數高，尤其在低溫區域中爲低黏性。此外，低蒸發性亦 佳。 由式（1)表示之二酯，並非單獨的化合物，而是構 成爲1及R2在上述範圍內變化之二酯的混合物，藉此可 提升低溫時的黏性、蒸發性及低溫流動性。 構成爲二酯的混合物時，本發明之潤滑油基油中，式 (1 )之 A : B : C的莫耳比係位於25〜65 : 3 0~50 : 3〜25 之範圍內，較佳位於35〜50: 40~50: 5~15之範圍內。在 此，A、B、C具有上述涵義，爲A僅是直鏈院基，B含 有直鏈烷基及分枝烷基兩者，且C僅是分枝烷基之情況， 藉由控制此等的比率，可提升特性。 本發明之潤滑油基油中，上述二酯的含量爲基油的 -9- 201241169 50wt%以上，較佳爲65wt%以上，更佳爲70wt%以上， 如此可充分地提升潤滑油在低溫時的低黏性、低蒸發性。 與其他基油成分混合之方法，在合成的方法中，可列 舉出將2-甲基-1，8-辛二醇以外的二醇混合並進行酯化之 方法，或是將2 -乙基己酸、辛酸或庚酸以外的酸混合並 進行酯化之方法。在混合的方法中，可列舉出與酯、聚α 烯烴等之既有的基油混合之方法。 其他基油成分中，含有在40 °C時的動黏度未達 9mm2/s、且係黏度指數爲1〇〇以上並具有新戊二醇骨架之 多元醇酯之低黏度油者，可一邊維持潤滑油在低溫時的低 黏性、低蒸發性，且更可賦予低溫流動性，故較佳。含有 此低黏度油時，較佳位於5〜30wt%之範圍內。此外，該 低黏度油較佳爲新戊二醇與辛酸或癸酸之酯化物。 作爲本發明之潤滑油基油的主成分之二酯，可藉由使 由2-甲基-1，8-辛二醇所構成之醇成分，與由2-乙基己酸 、辛酸及/或庚酸所構成之酸成分進行反應而得。此時， 酸成分必須含有具有分枝鏈之2-乙基己酸作爲必要成分 ，而辛酸及庚酸可含有其中一者或含有兩者。藉由控制酸 成分的使用比率，可得滿足上述莫耳比之二酯。然而，可 分別調配從2-甲基-1，8-辛二醇與2-乙基己酸所得之單獨 的二酯而得。 上述二酯，可依循一般方法，較佳係在氮氣等之非活 性氣體環境下、酯化觸媒的存在下或無觸媒的存在下，將 上述酸成分與醇成分加熱攪拌等以進行二酯化而調製出。In the formula, it is independently 1-ethylpentyl, n-heptyl or n-hexyl. Further, the molar ratio (A : B : C ) is in the range of 25 to 65 : 30 to 50 : 3 to 2 5 . Here, A is 1 and R2 are both n-heptyl or n-hexyl, B is one of Ri and the ruler 2 is 1-ethylpentyl, and C is 1 and R2 are 1-ethylpentyl. By. The above molar ratio (A: B: C) is particularly preferably in the range of 35 to 50: 40 to 50: 5 to 15. The lubricating base oil of the present invention is preferably 50% by weight or more based on the diester represented by the formula (1). In addition, the lubricating base oil of the present invention is preferably a low viscosity oil containing 5 to 30% by weight, and the low viscosity oil has a dynamic viscosity of less than 9 mm 2 /s at 40 ° C and a viscosity index of 100 or more. And a polyol ester having a neopentyl glycol skeleton, which is preferably a polyol ester obtained from octanoic acid or citric acid, and neopentyl glycol. Further, the present invention relates to a lubricating oil composition, which is characterized by The above-mentioned lubricating base oil is used to obtain β -8 - 201241169. [Embodiment] Hereinafter, embodiments of the present invention will be described. The lubricating base oil of the present invention is mainly composed of a diester represented by the above formula (1). It is preferred to contain 50% by weight or more of the diester represented by the formula (1). In the formula (1), Ri and 112 are independently 1-ethylpentyl, n-heptyl or n-hexyl. Ri and R2 may be the same or different. Here, the 1-ethylpentyl group is a branched alkyl group, and the n-heptyl group and the n-hexyl group are linear alkyl groups. In the above diester, R and R2 are components derived from a carboxylic acid, specifically, 2-ethylhexanoic acid, octanoic acid or heptanoic acid. Further, among the above diesters, the component derived from an alcohol is 2-methyl-1,8-octanediol. Since the diester does not excessively have a branched chain, the viscosity index is high, especially in a low temperature region. In addition, low evaporation is also good. The diester represented by the formula (1) is not a single compound but a mixture of diesters in which 1 and R2 are changed within the above range, whereby viscosity, evaporability and low-temperature fluidity at low temperatures can be improved. When the mixture is composed of a diester, in the lubricating base oil of the present invention, the molar ratio of A:B:C of the formula (1) is in the range of 25 to 65:30 to 50:3 to 25, Good is located in the range of 35~50: 40~50: 5~15. Here, A, B, and C have the above meanings, and A is a linear chain base, B contains both a linear alkyl group and a branched alkyl group, and C is only a branched alkyl group, by controlling this. The ratio of equals can improve the characteristics. In the lubricating base oil of the present invention, the content of the above diester is from -9 to 201241169 50% by weight of the base oil, preferably 65 wt% or more, more preferably 70 wt% or more, so that the lubricating oil can be sufficiently raised at a low temperature. Low viscosity, low evaporation. In the method of mixing with other base oil components, a method of mixing and esterifying a diol other than 2-methyl-1,8-octanediol, or 2-ethyl group, may be mentioned. A method in which an acid other than caproic acid, caprylic acid or heptanoic acid is mixed and esterified. The method of mixing may be a method of mixing with a base oil such as an ester or a polyalphaolefin. Other base oil components, which contain a low viscosity oil having a dynamic viscosity of less than 9 mm 2 /s at 40 ° C and a viscosity index of 1 〇〇 or more and a neopentyl glycol skeleton, can be maintained while maintaining Lubricating oil is preferred because it has low viscosity at low temperatures, low evaporability, and imparts low-temperature fluidity. When the low viscosity oil is contained, it is preferably in the range of 5 to 30% by weight. Further, the low viscosity oil is preferably an ester of neopentyl glycol with caprylic acid or citric acid. The diester which is a main component of the lubricating base oil of the present invention can be obtained by reacting an alcohol component composed of 2-methyl-1,8-octanediol with 2-ethylhexanoic acid, octanoic acid and/or Or the acid component of heptanoic acid is reacted. At this time, the acid component must contain 2-ethylhexanoic acid having a branched chain as an essential component, and caprylic acid and heptanoic acid may contain one or both. By controlling the use ratio of the acid component, a diester satisfying the above molar ratio can be obtained. However, it is possible to separately provide a separate diester obtained from 2-methyl-1,8-octanediol and 2-ethylhexanoic acid. The diester may be subjected to a general method, and preferably, the acid component and the alcohol component are heated and stirred in the presence of an esterification catalyst or a non-catalyst in an inert gas atmosphere such as nitrogen or the like. It is prepared by esterification.
-10- 201241169 具體方法，可列舉出在高溫下進行縮合反應，並一邊去除 所生成的水一邊進行酯化之合成方法。該反應中，可爲無 觸媒，或是使用硫酸、對甲苯磺酸、四烷氧鈦酸酯等之觸 媒，此外，亦可併用甲苯、乙基苯、二甲苯等之.脫水溶劑 。進行酯化反應時，酸成分，例如相對於醇成分1莫耳爲 2.0莫耳以上，較佳係使用2.01〜4.5莫耳。 本發明之潤滑油基油，係成爲液狀潤滑油及滑脂等之 潤滑油組成物的基油。本發明之潤滑油組成物，係使用該 基油，並將用以提升潤滑油組成物的性能之成分調配於基 油者，該成分有一般所知的抗氧化劑、油性劑、抗磨耗劑 、極壓劑、金屬非活性劑、防銹劑、黏度指數提升劑、流 動點降低劑、消泡性等之添加劑或增稠劑。該添加劑可適 當地調配1種以上。此等添加劑，相對於潤滑油基油，較 佳爲 0.01~10wt%，更佳爲 〇.〇3~5wt%。 當本發明之潤滑油基油爲滑脂時，使用於此之增稠劑 並無特別限定，可適當地使用通常被使用在滑脂者。例如 可列舉出金屬皂、複合皂、脲、有機皂土、二氧化矽等。 滑脂中的增稠劑含量，通常較適當者爲3 ~30wt% »此外 ’滑脂中’可適當地調配1種或2種以上之一般所調配的 抗氧化劑 '極壓劑、防銹劑、抗金屬腐蝕劑、油性劑、黏 度指數提升劑、流動點降低劑、附著性提升劑等之添加劑 。此等添加劑，一般相對於滑脂基油，較佳爲〇.〇1 ~l〇wt %，更佳爲0.03〜5wt%。 使用本發明之潤滑油基油之潤滑油組成物，以動作油 •11 - 201241169 、齒輪油、主軸油、軸承油等之工業用潤滑劑爲首，可應 用在動壓軸承油、燒結含油軸承油、鉸鏈油、縫紉油、滑 動面油等之各種用途。滑脂可應用在軸承部（滾珠、滾子 、滾針）、滑動部、齒輪部等之各種潤滑部。尤其能夠有 利地應用在流體軸承單元、流體動壓軸承單元、多孔質含 油軸承單元，以及具備此等單元之主軸馬達》 以下係顯示出適合使用本發明之潤滑油組成物的例子 〇 1)流體軸承單元：係設置有藉由中介存在於軸外周 面與軸套內周面的間隙之潤滑油的油膜壓力來支撐旋轉軸 之軸承部，並使用本發明之潤滑油組成物作爲潤滑劑之軸 承單元。2)流體動壓軸承單元··在軸外周面與軸套內周 面的中的任一方設置動壓產生槽，並使用本發明之潤滑油 組成物作爲潤滑劑之軸承單元。3 )多孔質含油軸承單元 :具備含浸有本發明之潤滑油組成物之多孔質含油軸承。 4)多孔質含油軸承：含浸有本發明之潤滑油組成物之軸 承。該多孔質含油軸承較佳可列舉出動壓型多孔質含油軸 承。5)主軸馬達：具備上述軸承單元之主軸馬達。 [實施例] 以下係列舉出實施例來詳細說明本發明，但本發明並 不限定於下列實施例》%在無特別言明時，爲wt%。 實施例1 -12- 201241169 將作爲脂肪族二價醇的2 -甲基-1，8 -辛二醇24.05g、 作爲飽和脂肪族單羧酸（以下稱爲羧酸）之辛酸32.01 g、 2-乙基己酸54.51g放入於由300cc的四頸燒瓶、加熱裝 置、攪拌裝置、溫度計、氮氣通氣管及氮氣管線、迪安-斯塔克裝置、冷卻管及冷卻管線所構成之反應裝置中，以 四（IV) ( 2-乙基-1-己氧基）鈦酸酯〇.lg作爲觸媒，於 氮氣環境中，在170°C、攪拌48小時以反應至完全酯化 爲止。在lOTorr、170t下將反應油中所殘留之羧酸的大 部分餾除，然後使觸媒失去活性，將殘留於酯中的酸中和 ，並藉由吸附處理來去除酯中的未反應物或雜質，而得二 酯（D1 )。 二酯組成的決定，係從氣相層析法中之面積比來算出 莫耳比。二酯（D1)，當以式（1)中之Rr r2兩者非分 枝烷基者爲A，任一者爲分枝烷基者爲B，兩者爲分枝烷 基者爲 C 時，A: B: C = 47.9: 42.7: 9.4(莫耳比），A 、B、C的合計爲全組成的96.0%。 實施例2 以與實施例1相同的方法，將以2 -甲基-1，8 -辛二醇 24.05g、作爲羧酸之辛酸31.〇4g、2-乙基己酸5 8.65 g作爲 原料者進行酯化’而得二酯（D2)。二酯（D2)的組成 爲 A: B: C = 45.0: 44.1: 10.9，A、B、C 的合計爲全組 成的96.0%。 -13- 201241169 實施例3 以與實施例1相同的方法，將以2-甲基-1，8-辛二醇 24.05g、作爲羧酸之辛酸30.10g、2-乙基己酸59.53 g作爲 原料者進行酯化，而得二酯（D3 )。二酯（D3 )的組成 爲 A: B: C = 42.9: 45.8: 11.3，A、B、C 的合計爲全組 成的95.5%。 實施例4 以與實施例1相同的方法，於原料中使用由2-甲基-1，8-辛二醇83%、及1，9_壬二醇15%所構成之二醇 24.05g ’並將以該二醇與作爲羧酸之辛酸29.04g、2-乙基 己酸59.53 g作爲原料者進行酯化，而得二酯（D4)。二 酯（D4)的組成爲 A: B: C = 39.4: 46.6: 14.0，A、B、 C的合計爲全組成的82.8%。 實施例5 將95wt%之實施例2中所合成之二酯（〇2)與5wt %之新戊二醇的二醋（Hatco公司製）混合而得二酯（D5 )° 實施例6 將70wt%之實施例2中所合成之二酯（〇2)與3 0wt %的^962混合而得二酯（D6)。-10- 201241169 The specific method includes a synthesis method in which a condensation reaction is carried out at a high temperature and esterification is carried out while removing the generated water. In the reaction, a catalyst such as sulfuric acid, p-toluenesulfonic acid or tetraalkoxy titanate may be used without a catalyst, and a dehydrating solvent such as toluene, ethylbenzene or xylene may be used in combination. When the esterification reaction is carried out, the acid component is, for example, 2.0 mol or more per mol of the alcohol component, and preferably 2.01 to 4.5 mol. The lubricating base oil of the present invention is a base oil of a lubricating oil composition such as a liquid lubricating oil or a grease. The lubricating oil composition of the present invention uses the base oil and blends a component for improving the performance of the lubricating oil composition to a base oil, which is generally known as an antioxidant, an oily agent, an anti-wear agent, Additives or thickeners such as extreme pressure agents, metal inactive agents, rust inhibitors, viscosity index enhancers, pour point depressants, defoaming agents, and the like. The additive can be appropriately formulated in one or more types. These additives are preferably 0.01 to 10% by weight, more preferably 〇. 〇 3 to 5 % by weight, based on the lubricating base oil. When the lubricating base oil of the present invention is a grease, the thickener used therefor is not particularly limited, and those which are usually used in the grease can be suitably used. For example, metal soap, complex soap, urea, organic bentonite, cerium oxide, or the like can be given. The content of the thickener in the grease is usually 3 to 30% by weight in addition to the appropriate one. In addition, one or more kinds of generally formulated antioxidants, extreme pressure agents and rust inhibitors, can be appropriately formulated in the 'grease grease'. Additives such as metal corrosion inhibitors, oily agents, viscosity index improvers, pour point depressants, adhesion promoters, etc. These additives are generally preferably from 〇1 to 10% by weight, more preferably from 0.03 to 5% by weight, based on the grease base oil. The lubricating oil composition of the lubricating base oil of the present invention is mainly used as an industrial lubricant such as a working oil, 11 - 201241169, gear oil, spindle oil, bearing oil, etc., and can be applied to dynamic pressure bearing oil and sintered oil bearing. Various uses such as oil, hinge oil, sewing oil, and sliding oil. Grease can be applied to various lubrication parts such as bearings (balls, rollers, needles), sliding parts, and gear parts. In particular, it can be advantageously applied to a fluid bearing unit, a fluid dynamic bearing unit, a porous oil-impregnated bearing unit, and a spindle motor having such a unit. Hereinafter, an example of a lubricant composition suitable for use of the present invention is shown. Bearing unit: a bearing portion that supports the rotating shaft by an oil film pressure of a lubricating oil that intervenes in a gap between the outer peripheral surface of the shaft and the inner peripheral surface of the sleeve, and uses the lubricating oil composition of the present invention as a lubricant bearing unit. 2) Fluid dynamic pressure bearing unit: A dynamic pressure generating groove is provided in one of the outer circumferential surface of the shaft and the inner circumferential surface of the sleeve, and the lubricating oil composition of the present invention is used as a bearing unit of the lubricant. 3) Porous oil-impregnated bearing unit: A porous oil-impregnated bearing impregnated with the lubricating oil composition of the present invention. 4) Porous oil-impregnated bearing: a bearing impregnated with the lubricating oil composition of the present invention. The porous oil-impregnated bearing is preferably a dynamic pressure type porous oil bearing. 5) Spindle motor: A spindle motor having the above bearing unit. [Examples] The present invention will be described in detail in the following examples, but the present invention is not limited to the following examples, and % is % by weight unless otherwise specified. Example 1 -12-201241169 24.05 g of 2-methyl-1,8-octanediol as an aliphatic divalent alcohol, 32.01 g, 2 of octanoic acid as a saturated aliphatic monocarboxylic acid (hereinafter referred to as a carboxylic acid) -54.51g of ethylhexanoic acid was placed in a reaction apparatus consisting of a 300cc four-necked flask, a heating device, a stirring device, a thermometer, a nitrogen vent pipe, a nitrogen gas line, a Dean-Stark device, a cooling pipe, and a cooling line. Among them, tetrakis(IV)(2-ethyl-1-hexyloxy) titanate lg.lg was used as a catalyst, and the mixture was stirred at 170 ° C for 48 hours in a nitrogen atmosphere to be completely esterified. The majority of the carboxylic acid remaining in the reaction oil is distilled off at 10 Torr, 170 t, and then the catalyst is deactivated, the acid remaining in the ester is neutralized, and the unreacted substance in the ester is removed by adsorption treatment. Or an impurity to obtain a diester (D1). The determination of the diester composition is based on the area ratio in the gas chromatography to calculate the molar ratio. Diester (D1), when Rr r2 in formula (1) is not branched alkyl, A is either B, and either is branched alkyl, C is the case , A: B: C = 47.9: 42.7: 9.4 (Morby), the total of A, B, and C is 96.0% of the total composition. Example 2 In the same manner as in Example 1, 24.05 g of 2-methyl-1,8-octanediol, 31. g of octanoic acid as a carboxylic acid, and 5.85 g of 2-ethylhexanoic acid were used as raw materials. The esterification was carried out to obtain a diester (D2). The composition of the diester (D2) was A: B: C = 45.0: 44.1: 10.9, and the total of A, B, and C was 96.0% of the total composition. -13- 201241169 Example 3 In the same manner as in Example 1, 24.05 g of 2-methyl-1,8-octanediol, 30.10 g of octanoic acid as a carboxylic acid, and 59.53 g of 2-ethylhexanoic acid were used. The raw material is subjected to esterification to obtain a diester (D3). The composition of the diester (D3) is A: B: C = 42.9: 45.8: 11.3, and the total of A, B, and C is 95.5% of the total composition. Example 4 In the same manner as in Example 1, a diol of 24.05 g composed of 2-methyl-1,8-octanediol 83% and hexamethylene glycol 15% was used as a raw material. Further, the diol was esterified with 29.04 g of octanoic acid as a carboxylic acid and 59.53 g of 2-ethylhexanoic acid as a raw material to obtain a diester (D4). The composition of the diester (D4) was A: B: C = 39.4: 46.6: 14.0, and the total of A, B, and C was 82.8% of the total composition. Example 5 95 wt% of the diester (〇2) synthesized in Example 2 and 5 wt% of neopentyl glycol diacetate (manufactured by Hatco Co., Ltd.) were mixed to obtain a diester (D5). Example 6 70 wt The diester (〇2) synthesized in Example 2 was mixed with 30% by weight of ^962 to obtain a diester (D6).
14- 201241169 實施例7 以與實施例1相同的方法，將以2-甲基-1，8-辛二醇 3 2.05g、作爲羧酸之庚酸46.87g、2-乙基己酸68.5 0g作爲 原料者進行酯化，而得二酯（D 1 1 )。二酯（D 1 1 )的組 成爲 A: B: C = 57.2: 37.3: 5.5，A、B、C 的合計爲全組 成的99.2%。 實施例8 以與實施例1相同的方法，將以2-甲基-1,8-辛二醇 32.05g、作爲羧酸之庚酸47.〇ig、2-乙基己酸5 8.7 3 g作爲 原料者進行酯化，而得二酯（D12)。二酯（D12)的組 成爲 A: B: C = 62.4: 33.2: 4.4，A、B、C 的合計爲全組 成的99.2%。 比較例1 以與實施例1相同的方法，將以2_甲基-丨，8_辛二醇 、作爲羧酸之辛酸、2 -乙基己酸作爲原料者進行酯化，而 得一酯（D7) ° —酯（D7)的組成爲 a: B: C = 74.5: 23_5: 2.0，A、B、C的合計爲全組成的98〇% ^ 比較例2 以與實施例4相同的方法，於原料中使用由2_甲基_ 1’8辛—冑83/6、及1ί9-壬二_ 15%所構成之二醇 24.05g，並將以該：醇與作爲殘酸之辛酸、2_乙基己酸作 -15- 201241169 爲原料者進行酯化，而得二酯（D8 )。二酯（D8 )的組 成爲 A: B: C = 22.9: 49.9: 14.0，A、B、C 的合計爲全 組成的8 3.7 %。 比較例3 以與實施例1相同的方法，以1,8-辛二醇與2-乙基己 酸作爲原料進行酯化，而得二酯（D9 )。 比較例4 以與實施例1相同的方法，以2,4-二乙基-1，5-戊二醇 與辛酸作爲原料進行酯化，而得二酯（D10)。 第1表係顯示實施例及比較例中所得之二酯（D 1 ) ~ (D12)之A、B、C的合計及各種物性。 -16- 201241169 [第1表] A+B+C的合計 % 動黏度 ramVs 流動點 X： 酸値 mgKOH/g 蒸發減少量 % 實施例1 96.0 89.0 -37.5 0. 03 1. 79 實施例2 96.0 91.8 -40.0 0. 03 1.85 實施例3 95.5 92.8 -40.0 0. 03 2.00 實施例4 82.8 93.8 -35.0 0.03 2.02 實施例5 91.5 86· 7 -40. 0 0. 03 2. 10 實施例6 67.4 78.7 < -45. 0 0. 03 2. 78 實施例7 99. 2 66.3 -45.0 0.03 2.41 實施例8 99.2 62.4 -40.0 0. 03 2. 65 比較例1 98.0 85.0 25.0 0. 03 1. 51 比較例2 83. 7 95.9 -40.0 0. 03 2. 35 比較例3 - 95.3 < -45. 0 0.03 2.89 比較例4 - 93.8 < -45. 0 0.03 4.20 第1表中，動黏度爲-10 °c時之値。蒸發減少量爲在 氮氣環境中、120°C下以熱天平將二酯保持8h後之重量減 少量（％ )。 將下列添加劑調配於上述所得之二酯中而構成潤滑油 組成物。 添加劑及略稱 L57 :烷基二苯基胺（BASF公司製的1rganox L57、 抗氧化劑） IR39:苯並三唑衍生物（BASF公司製的1rgamet 39 、金屬非活性劑）14-201241169 Example 7 In the same manner as in Example 1, 2.05 g of 2-methyl-1,8-octanediol, 46.87 g of heptanoic acid as a carboxylic acid, and 68.5 0 g of 2-ethylhexanoic acid were used. Esterification is carried out as a raw material to obtain a diester (D 1 1 ). The group of diesters (D 1 1 ) became A: B: C = 57.2: 37.3: 5.5, and the total of A, B, and C was 99.2% of the total composition. Example 8 In the same manner as in Example 1, 32.05 g of 2-methyl-1,8-octanediol, heptanoic acid as a carboxylic acid 47. 〇ig, and 2-ethylhexanoic acid 5 8.7 3 g were used. Esterification is carried out as a raw material to obtain a diester (D12). The group of the diester (D12) becomes A: B: C = 62.4: 33.2: 4.4, and the total of A, B, and C is 99.2% of the total composition. Comparative Example 1 In the same manner as in Example 1, esterification was carried out by using 2-methyl-oxime, 8-octanediol, octanoic acid as a carboxylic acid, and 2-ethylhexanoic acid as a raw material to obtain an ester. (D7) ° - The composition of the ester (D7) is a: B: C = 74.5: 23_5: 2.0, and the total of A, B, and C is 98% of the total composition ^ Comparative Example 2 In the same manner as in Example 4 24.05 g of a diol consisting of 2_methyl-1'8-octyl- 83/6, and 1 ί- 9- 15% is used as a raw material, and the alcohol and the octanoic acid as a residual acid are used. 2_ethylhexanoic acid as -15- 201241169 The esterified product was obtained as a raw material to obtain a diester (D8). The group of the diester (D8) becomes A: B: C = 22.9: 49.9: 14.0, and the total of A, B, and C is 83.7 % of the total composition. Comparative Example 3 In the same manner as in Example 1, esterification was carried out using 1,8-octanediol and 2-ethylhexanoic acid as a raw material to obtain a diester (D9). Comparative Example 4 In the same manner as in Example 1, esterification was carried out using 2,4-diethyl-1,5-pentanediol and octanoic acid as a raw material to obtain a diester (D10). The first table shows the total of A, B, and C of the diesters (D 1 ) to (D12) obtained in the examples and the comparative examples, and various physical properties. -16- 201241169 [Table 1] Total of A+B+C % Dynamic viscosity ramVs Flow point X: Acid 値mgKOH/g Evaporation reduction % Example 1 96.0 89.0 -37.5 0. 03 1. 79 Example 2 96.0 91.8 -40.0 0. 03 1.85 Example 3 95.5 92.8 -40.0 0. 03 2.00 Example 4 82.8 93.8 -35.0 0.03 2.02 Example 5 91.5 86· 7 -40. 0 0. 03 2. 10 Example 6 67.4 78.7 <; -45. 0 0. 03 2. 78 Example 7 99. 2 66.3 -45.0 0.03 2.41 Example 8 99.2 62.4 -40.0 0. 03 2. 65 Comparative Example 1 98.0 85.0 25.0 0. 03 1. 51 Comparative Example 2 83. 7 95.9 -40.0 0. 03 2. 35 Comparative Example 3 - 95.3 < -45. 0 0.03 2.89 Comparative Example 4 - 93.8 < -45. 0 0.03 4.20 In Table 1, the dynamic viscosity is -10 °c The time is right. The amount of evaporation reduction was a small amount (%) of the weight after maintaining the diester for 8 hours with a thermobalance in a nitrogen atmosphere at 120 °C. The following additives were formulated in the diester obtained above to constitute a lubricating oil composition. Additives and abbreviations L57 : alkyl diphenylamine (1rganox L57, antioxidant manufactured by BASF) IR39: benzotriazole derivative (1rgamet 39, metal inactive agent manufactured by BASF)
Chemical 公司 OAS 1200 :琥珀酸醯亞胺（Chevron -17- 201241169 製的OAS 1 200、無灰系分散劑） 實施例9〜1 1 以實施例2、5或6中所得之二酯（D2) 、（D5)或 (D6)作爲基油，調配 〇.5wt% 的 L57、〇.〇3wt% 的 IR39 、及1.5wt%的OAS 1 200而構成潤滑油組成物。 比較例5 以比較例3中所得之二酯（D 9 )作爲基油，調配 〇.5wt% 的 L57、0.03wt% 的 IR39、及 1.5wt% 的 OAS1200 而構成潤滑油組成物。 對上述潤滑油組成物進行蒸發試驗，以及以模擬使用 於含油軸承時的軸承扭矩者爲目的而進行-10 °c時之旋轉 黏度的評估。 蒸發試驗係在100°C、6000小時的條件下進行。蒸發 試驗，係將試樣2g放入於LABORANR螺紋管瓶#3 (容積 9 ml)來進行。n數設爲2，並求取該平均値作爲蒸發減少 量。對於調配有添加劑之潤滑油組成物，係以在1 oo°c、 6000小時的條件下蒸發減少量爲0.5%以下者爲合格。顯 示出0.5%以上的蒸發減少量之潤滑油，爲人所知者爲在 進行6000小時以上時，蒸發減少量有呈指數函數地增加 之傾向。 使用於含油軸承時形成問題之旋轉特性，爲低溫扭矩 。尤其在-10 °c時的旋轉扭矩較大時，對電池的負擔亦增 -18- 201241169 加。因此，係測定-10 °c時的旋轉扭矩並模擬在實際機械 中的軸承扭矩。因馬達製造商的不同，會有要求-10 °c時 的旋轉黏度爲100 mPa · S以下之規格。因此以該黏度以 下者爲合格。 測定機器係使用Anton-Paar製的SVM-3000。 [第2表] 基油 動黏度 mPa* s 流動點 X： 酸値 mgKOH/g 蒸發減少量 % 實施例9 D2 96. 2 -37.5 0. 03 0. 39 實施例10 D5 95. 1 -32. 5 0. 03 0. 41 實施例11 D6 87. 7 -42.5 0· 03 0. 45 比較例5 D9 102. 9 < -45. 0 0.03 0.80 第2表係顯示對上述潤滑油組成物實施接近於實態之 評估試驗之結果。動黏度爲-1 0 °C時之値。任一實施例中 ，均顯示出比較例之一半蒸發減少量的0.5%以下之値。 此外，同時確認到旋轉特性亦爲基準値以下，而能夠得到 至目前爲止具有取捨關係而難以同時達成之低溫-低扭矩 與高溫-低蒸發之潤滑油組成物。 具體而言，實施例9之潤滑油組成物的蒸發減少量最 少，旋轉黏度亦爲基準値以下。此外，使用多元醇酯作爲 基油的一部分之實施例1 0及1 1，係確認到可在不會對蒸 發減少量造成較大阻礙下使黏度降低。比較例5之潤滑油 組成物，在既有基油中爲均衡性最佳而被採用於許多小型 -19- 201241169 馬達中’但開發具有凌駕此性能之潤滑油者，可說是有益 於小型馬達的高性能化（長壽命、省能源）。 產業上之可利用性： 本發明之潤滑油基油，可提供一種具有低揮發性且低 溫流動性佳之特長，並且在低溫至高溫之寬廣區域中可長 時間顯現出潤滑性之潤滑油組成物。尤其在資訊機器相關 中，可在不損及小型主軸馬達用軸承的耐久性下，實現低 扭矩化（尤其是低溫驅動性）。 -20-Chemical Company OAS 1200: succinimide succinimide (OAS 1 200, ashless dispersant manufactured by Chevron -17-201241169) Examples 9 to 1 1 The diester (D2) obtained in Example 2, 5 or 6 (D5) or (D6) as a base oil, a lubricating oil composition is prepared by blending 5% by weight of L57, 〇. 〇 3 wt% of IR39, and 1.5 wt% of OAS 1 200. Comparative Example 5 Using the diester (D9) obtained in Comparative Example 3 as a base oil, 5% by weight of L57, 0.03% by weight of IR39, and 1.5% by weight of OAS1200 were blended to constitute a lubricating oil composition. The above lubricating oil composition was subjected to an evaporation test and an evaluation of the rotational viscosity at -10 °c for the purpose of simulating the bearing torque used in the oil-impregnated bearing. The evaporation test was carried out at 100 ° C for 6000 hours. In the evaporation test, 2 g of the sample was placed in LABORANR screw bottle #3 (volume 9 ml). The n number is set to 2, and the average enthalpy is obtained as the evaporation reduction amount. For the lubricating oil composition to which the additive is formulated, the evaporation reduction amount of 0.5% or less under the conditions of 1 oo ° C and 6000 hours is acceptable. It is known that a lubricating oil having an evaporation reduction of 0.5% or more tends to increase exponentially as a function of 6,000 hours or more. The rotational characteristics that are problematic when used in oil-impregnated bearings are low temperature torque. Especially when the rotational torque is large at -10 °c, the burden on the battery is also increased -18- 201241169 plus. Therefore, the rotational torque at -10 °c is measured and the bearing torque in the actual machine is simulated. Depending on the motor manufacturer, there is a requirement for a rotational viscosity of -100 mPa · S at -10 °c. Therefore, the following ones are qualified. The measuring machine used SVM-3000 manufactured by Anton-Paar. [Table 2] Base oil dynamic viscosity mPa* s Flow point X: Acid 値mgKOH/g Evaporation reduction % Example 9 D2 96. 2 -37.5 0. 03 0. 39 Example 10 D5 95. 1 -32. 5 0. 03 0. 41 Example 11 D6 87. 7 -42.5 0· 03 0. 45 Comparative Example 5 D9 102. 9 < -45. 0 0.03 0.80 The second watch shows that the above lubricating oil composition is implemented close to The results of the evaluation test in the actual state. The dynamic viscosity is -1 at -10 °C. In any of the examples, the enthalpy of 0.5% or less of the half evaporation reduction amount of the comparative example was shown. In addition, it has been confirmed that the rotational characteristics are also below the reference value, and it is possible to obtain a lubricating oil composition having a low-low torque and a high-temperature-low evaporation which are difficult to achieve at the same time. Specifically, the lubricating oil composition of Example 9 had the least amount of evaporation reduction, and the rotational viscosity was also below the reference enthalpy. Further, in Examples 10 and 1 using a polyol ester as a part of the base oil, it was confirmed that the viscosity can be lowered without causing a large hindrance to the amount of reduction in evaporation. The lubricating oil composition of Comparative Example 5 is optimally used in the existing base oil and is used in many small -19-201241169 motors. However, it is beneficial to develop a lubricating oil having this performance. High performance of the motor (long life, energy saving). Industrial Applicability: The lubricating base oil of the present invention can provide a lubricating oil composition which has a low volatility and good low-temperature fluidity, and exhibits lubricity for a long period of time in a wide region from a low temperature to a high temperature. . In particular, in the information machine related, it is possible to achieve low torque (especially low-temperature driveability) without impairing the durability of the small-spindle motor bearing. -20-