Provided is a lubricant composition including a bicyclic liquid crystal of formula (1), and a tricyclic liquid crystal compound of formula (2), and having a mixing mass ratio of the bicyclic liquid crystal compound and tricyclic liquid crystal compound of 95:5 to 15:85. The composition is suitable for use in a clean environment, under a high vacuum, under high temperature and a bearing.

##STR00001##

R.sup.1 and R.sup.2 are the same or different from each other, and each is —OCH.sub.2CH.sub.2CH(R′)CH.sub.2CH.sub.2OR

##STR00002##

R.sup.11 and R.sup.21 are the same or different from each other, and each is —OR. R.sup.12, R.sup.13, R.sup.22 and R.sup.23 are the same or different from each other, and each is hydrogen or —OR. R is a linear or branched C.sub.nH.sub.2n+1, 1≤n≤20 and R′ is methyl or ethyl.

Provided is a lubricant composition including a bicyclic liquid crystal of formula (1), and a tricyclic liquid crystal compound of formula (2), and having a mixing mass ratio of the bicyclic liquid crystal compound and tricyclic liquid crystal compound of 95:5 to 15:85. The composition is suitable for use in a clean environment, under a high vacuum, under high temperature and a bearing. ##STR00001##
R.sup.1 and R.sup.2 are the same or different from each other, and each is —OCH.sub.2CH.sub.2CH(R′)CH.sub.2CH.sub.2OR ##STR00002##
R.sup.11 and R.sup.21 are the same or different from each other, and each is —OR. R.sup.12, R.sup.13, R.sup.22 and R.sup.23 are the same or different from each other, and each is hydrogen or —OR. R is a linear or branched C.sub.nH.sub.2n+1, 1≤n≤20 and R′ is methyl or ethyl.

This is to provide an electrically-conductive lubricant having characteristics in combination that it shows liquid crystallinity in a wide temperature range, retains low dynamic friction coefficient, has electrical-conductivity, has almost no loss due to evaporation, decomposition and the like, has a clean appearance, and emits fluorescence, and can find deterioration or leakage immediately.

This electrically-conductive lubricant comprises at least one kind of the compound (1) represented by the formula (1):

##STR00001##

[wherein, R.sup.11 and R.sup.21 are the same or different from each other, and each is hydrogen or a group —OCH.sub.2CH.sub.2CH(R′)CH.sub.2CH.sub.2OR (R is a linear or branched C.sub.nH.sub.2n+1, 4≤n≤12, and R′ is methyl or ethyl), and R.sup.12, R.sup.13, R.sup.22 and R.sup.23 are the same or different from each other, and each is a group —OCH.sub.2CH.sub.2CH(R′)CH.sub.2CH.sub.2OR (R is a linear or branched C.sub.nH.sub.2n+1, 4≤n≤12, and R′ is methyl or ethyl)].

Provided is a lubricant composition including a bicyclic liquid crystal of formula (1), tricyclic liquid crystal compounds of formula (2), and formula (3). The composition is suitable for use in a clean environment, under a high vacuum, under high temperature and a bearing.

##STR00001##

R.sup.1 and R.sup.2 are the same or different from each other, and each is —OCH.sub.2CH.sub.2CH(R′)CH.sub.2CH.sub.2OR.

##STR00002##

R.sup.11 and R.sup.21 are the same or different from each other, and each is —OR. R.sup.12, R.sup.13, R.sup.22 and R.sup.23 are the same or different from each other, and each is hydrogen or a group —OR.

##STR00003##

R.sup.31 and R.sup.41 are the same or different from each other, and each is —OCH.sub.2CH.sub.2CH(R′)CH.sub.2CH.sub.2OR. R.sup.32, R.sup.33, R.sup.42, and R.sup.43 are the same or different from each other, and each is hydrogen or —OCH.sub.2CH.sub.2CH(R′)CH.sub.2CH.sub.2OR. R is a linear or branched C.sub.nH.sub.2n+1, 1≤n≤20, and R′ is methyl or ethyl.

This is to provide an electrically-conductive lubricant having characteristics in combination that it shows liquid crystallinity in a wide temperature range, retains low dynamic friction coefficient, has electrical-conductivity, has almost no loss due to evaporation, decomposition and the like, has a clean appearance, and emits fluorescence, and can find deterioration or leakage immediately. This electrically-conductive lubricant comprises at least one kind of the compound (1) represented by the formula (1): ##STR00001##
12:8 wherein, R.sup.11 and R.sup.21 are the same or different from each other, and each is hydrogen or a group —OCH.sub.2CH.sub.2CH(R′)CH.sub.2CH.sub.2OR (R is a linear or branched C.sub.nH.sub.2n+1, 4≤n≤12, and R′ is methyl or ethyl), and R.sup.12, R.sup.13, R.sup.22 and R.sup.23 are the same or different from each other, and each is a group —OCH.sub.2CH.sub.2CH(R′)CH.sub.2CH.sub.2OR (R is a linear or branched C.sub.nH.sub.2n+1, 4≤n≤12, and R′ is methyl or ethyl)].