In one embodiment, a spacer fluid may comprise a base fluid and a surfactant package. The surfactant package may comprise one or more surfactants, where the surfactant package comprises a first surfactant having the chemical structure R(OC.sub.2H.sub.4).sub.xOH. R may be a hydrocarbyl group having from 9 to 20 carbon atom, and x may be an integer from 5 and 15. The first surfactant may have a hydrophilic-lipophilic balance (HLB) of from 12 to 13.5.

In one embodiment, a retarded acid system comprises an aqueous acid and a retarding surfactant. The aqueous acid may comprise from 5 wt. % to 25 wt. % of a strong acid, that is, an acid having a K.sub.a greater than or equal to 0.01. The aqueous acid may further comprise from 75 wt. % to 95 wt. % water. The retarding surfactant may have the general chemical formula R(OC.sub.2H.sub.4).sub.xOH where R is a hydrocarbon having from 11 to 15 carbon atoms and x is an integer from 6 to 10. The retarding surfactant may have a hydrophilic-lipophilic balance from 8 to 16.

The present invention relates to the well drilling field in petroleum industry, in particular to a nano-hybrid lubricant and method thereof, and oil-based drilling fluid. The lubricant comprises: graphite oxide and a biquaternary ammonium salt compound of which the cation part is represented by formula (1). The present invention also provides a method for preparation of the lubricant and an oil-based drilling fluid containing the lubricant. The lubricant provided in the present invention can be comprehended as a nano-hybrid material. Thus, oil-based drilling fluids that contain the lubricant provided in the present invention have lower lubrication coefficient and excellent lubricating property without or with little negative impact on rheological property of the oil fluid, and the lubricant provided in the present invention has excellent thermostability thus suitable for use in operation at a high temperature. ##STR00001##

The present invention relates to the well drilling field in petroleum industry, in particular to a nano-hybrid lubricant and method thereof, and oil-based drilling fluid. The lubricant comprises: graphite oxide and a biquaternary ammonium salt compound of which the cation part is represented by formula (1). The present invention also provides a method for preparation of the lubricant and an oil-based drilling fluid containing the lubricant. The lubricant provided in the present invention can be comprehended as a nano-hybrid material. Thus, oil-based drilling fluids that contain the lubricant provided in the present invention have lower lubrication coefficient and excellent lubricating property without or with little negative impact on rheological property of the oil fluid, and the lubricant provided in the present invention has excellent thermostability thus suitable for use in operation at a high temperature. ##STR00001##

The present invention describes the use of amine molecules (N) and phosphonic compounds (P) for coating surfaces intended to be used in the field of horology. Since these two types of compounds are alkaline and acid in nature, they form pairs of ions that interact with all types of surfaces, whether these are composed of mineral materials such as glass, metal, non-oxidized materials (inter alia gold, rhodium and their alloys), or also polymeric materials. Taking advantage of the surprising complementary nature of these two types of compounds, the present inventors propose a composition and a coating process that enable functionalization layers to be formed on any type of material, in particular those used in clock mechanisms.

The present invention describes the use of amine molecules (N) and phosphonic compounds (P) for coating surfaces intended to be used in the field of horology. Since these two types of compounds are alkaline and acid in nature, they form pairs of ions that interact with all types of surfaces, whether these are composed of mineral materials such as glass, metal, non-oxidized materials (inter alia gold, rhodium and their alloys), or also polymeric materials. Taking advantage of the surprising complementary nature of these two types of compounds, the present inventors propose a composition and a coating process that enable functionalization layers to be formed on any type of material, in particular those used in clock mechanisms.

A low transition temperature mixture (LTTM) or deep eutectic solvent (DES) useful as a lubricating oil base stock and lubricating oil including a eutectic mixture of at least a first component and at least a second component. The at least first component comprises a hydrogen bond acceptor and the at least second component comprises a hydrogen bond donor. The eutectic mixture includes an equilibrium phase between the at least first component and the at least second component. The equilibrium phase does not exhibit physical characteristics of the at least first component in an unmixed state and the at least second component in an unmixed state. The at least first component and the at least second component form an intermolecular interaction between each other sufficient to prevent crystallization of the at least first component and the at least second component in the eutectic mixture. The eutectic mixture is a liquid at 20 C.

A low transition temperature mixture (LTTM) or deep eutectic solvent (DES) useful as a lubricating oil base stock and lubricating oil including a eutectic mixture of at least a first component and at least a second component. The at least first component comprises a hydrogen bond acceptor and the at least second component comprises a hydrogen bond donor. The eutectic mixture includes an equilibrium phase between the at least first component and the at least second component. The equilibrium phase does not exhibit physical characteristics of the at least first component in an unmixed state and the at least second component in an unmixed state. The at least first component and the at least second component form an intermolecular interaction between each other sufficient to prevent crystallization of the at least first component and the at least second component in the eutectic mixture. The eutectic mixture is a liquid at 20 C.

The invention provides a water-soluble metal-working oil agent, including a component A, a component B, a component C, and a component D, wherein the component A is an ester compound which has a characteristic temperature, as measured in accordance with JIS K2242, of 570 C. or higher and which is contained in the water-soluble metal-working oil agent in an amount of 10 mass % or more with respect to the entire amount of the agent; the component B is at least one condensed fatty acid which is selected from a condensed fatty acid (1), produced through dehydration condensation of a hydroxycarboxylic acid, and a condensed fatty acid (2), produced through dehydration condensation of an alcoholic hydroxyl group of the condensed fatty acid (1) with a monovalent carboxylic acid, which has a characteristic temperature, as measured in accordance with JIS K2242, of 650 C. or higher, and which is contained in the water-soluble metal-working oil agent in an amount of 7.5 mass % or more with respect to the entire amount of the agent; the component C is a carboxylic acid which is contained in the water-soluble metal-working oil agent in an amount of 2 mass % or more with respect to the entire amount of the agent; and the component D is a basic compound contained in such a neutralization equivalent that at least the component B and component C are neutralized to cancel out the sum of the acid values thereof. The agent can provide excellent workability with a hard-to-work material and can prolong tool life.

The invention provides a water-soluble metal-working oil agent, including a component A, a component B, a component C, and a component D, wherein the component A is an ester compound which has a characteristic temperature, as measured in accordance with JIS K2242, of 570 C. or higher and which is contained in the water-soluble metal-working oil agent in an amount of 10 mass % or more with respect to the entire amount of the agent; the component B is at least one condensed fatty acid which is selected from a condensed fatty acid (1), produced through dehydration condensation of a hydroxycarboxylic acid, and a condensed fatty acid (2), produced through dehydration condensation of an alcoholic hydroxyl group of the condensed fatty acid (1) with a monovalent carboxylic acid, which has a characteristic temperature, as measured in accordance with JIS K2242, of 650 C. or higher, and which is contained in the water-soluble metal-working oil agent in an amount of 7.5 mass % or more with respect to the entire amount of the agent; the component C is a carboxylic acid which is contained in the water-soluble metal-working oil agent in an amount of 2 mass % or more with respect to the entire amount of the agent; and the component D is a basic compound contained in such a neutralization equivalent that at least the component B and component C are neutralized to cancel out the sum of the acid values thereof. The agent can provide excellent workability with a hard-to-work material and can prolong tool life.