TWI452130B - Metal rolling oil composition - Google Patents

Description

Metal roll oil composition

This invention relates to a metal roll oil composition for use in cold rolling of metals.

As a cold-rolling oil which is conventionally used, a monomer such as mineral oil, animal and vegetable fats and oils, a synthetic ester or a mixture thereof is used as a base oil, and an oil-based lifting agent such as a fatty acid, an extreme pressure additive such as a phosphate ester, and an rust preventive agent are blended therein. Additives, antioxidants, emulsifiers, etc. Usually, the cold-rolled oil is emulsified and dispersed in water to prepare an emulsified dispersion having a concentration of about 1 to 10% by volume.

The emulsified dispersion is generally referred to as a coolant, and is generally used in a circulating manner in which a pump is supplied from a nozzle to a work roll and a steel sheet through a pump and returned to the tank. The cold-rolled oil used in this cycle is lubricated by the action of being spread on the surface of the work rolls and the steel sheet (referred to as plate-out property).

In recent years, with the advancement of the roll technology, the speed and mass production of the rolls have been sought, and the desired lubricity of the metal roll oil or the emulsion stability at the time of recycling has been further improved. Examples of the metal roll oil composition excellent in emulsion stability and spreadability include the metal roll oil compositions of Patent Documents 1 to 3.

Patent Document 1: Japanese Patent Laid-Open No. Hei 8-325588

Patent Document 2: Japanese Patent Laid-Open No. Hei 10-298580

Patent Document 3: Japanese Patent Laid-Open Publication No. 2008-7544

However, the metal roll oil compositions of Patent Documents 1 to 3 have been confirmed to have improved emulsion stability, but it is difficult to say that the spreadability is sufficiently excellent as compared with the conventional roll oil composition.

In order to carry out the emulsification dispersion, a cold-rolling oil such as a nonionic surfactant or an anionic surfactant is blended, and the spreadability is changed by the adjustment of the type or the amount of the surfactant. For example, when the blending amount of the HLB or the surfactant of the nonionic surfactant is adjusted to improve the emulsion stability of the coolant, the spreadability is lowered and the lubricity is insufficient. Further, if the amount of the HLB or the surfactant to be added to the nonionic surfactant is adjusted, the particle size of the coolant is increased, and the spreadability is improved, the emulsified state of the coolant becomes unstable, causing various kinds of cycles. malfunction.

That is, in the method of preparing a suitable surfactant, there is a trade-off between the emulsion stability of the coolant and the spreadability, and therefore a coolant which coexists is required. An object of the present invention is to provide a metal roll oil composition which is excellent in both emulsion stability and spreadability.

According to a first aspect of the invention, there is provided a metal roll oil composition comprising at least one base oil selected from the group consisting of mineral oil, animal and vegetable oils, and synthetic esters, a surfactant, and an elastomer.

In the first aspect of the invention, it is preferable to contain 0.1 part by mass or more and 10 parts by mass or less of the surfactant, and 0.05 part by mass or more and 20 parts by mass or less of the elastomer with respect to 100 parts by mass of the base oil.

In the first aspect of the invention, it is preferred to further contain an oily agent.

In the first aspect of the invention, it is preferred to further contain an antioxidant.

The second invention is a coolant obtained by dispersing the metal roll oil composition of the first invention in water.

According to the metal roll oil composition of the present invention and the coolant containing the metal roll oil composition, both of emulsion stability and spreadability can be obtained.

The metal roll oil composition of the present invention comprises a base oil, a surfactant, and an elastomer.

(base oil)

As the base oil used in the present invention, it is conventionally possible to use it in a user of such a metal roll oil composition. Specific examples include mineral oils such as spindle oil, engine oil, turbine oil, and cylinder oil; animal and vegetable oils such as whale oil, butter, lard, rapeseed oil, castor oil, rice bran oil, palm oil, and coconut oil; Fatty acid obtained from oil, castor oil, coconut oil, etc., and monoester of synthetic fatty acid and aliphatic monohydric alcohol having 1 to 22 carbon atoms, the above fatty acid and synthetic fatty acid and ethylene glycol, neopentyl glycol, trimethylolpropane And synthetic esters such as di-, tri- or tetra-esters of polyhydric alcohols such as pentaerythritol. The base oil may also be used in combination of two or more of these mineral oils, animal and vegetable oils, and synthetic esters.

(surfactant)

As the surfactant, an anionic surfactant, a cationic surfactant, or a nonionic surfactant can be used. Examples of the anionic surfactant include a sodium alkanesulfonate, a sodium naphthenate soap, and an alkylbenzenesulfonate sodium salt. The cationic surfactant may, for example, be an alkyltrimethylammonium salt, a dialkyldimethylammonium chloride or an alkylpyridinium chloride.

As the nonionic surfactant, for example, at least one of a copolymer of propylene glycol and ethylene glycol, a higher fatty acid, a polybasic fatty acid, and a polycondensed hydroxy fatty acid, and a polyhydric alcohol such as polyethylene glycol, glycerin or sorbitol can be used. At least one of a monoester or a polyester. The bonding form of the copolymer of propylene glycol and ethylene glycol is not particularly limited, and for example, it may be a block polymerization or a random polymerization. Further, the modified polyolefin may be copolymerized, and as the modified polyolefin, maleic acid polybutene may be mentioned. The higher fatty acid may, for example, be a saturated or unsaturated monobasic fatty acid having 12 to 18 carbon atoms, such as lauric acid, myristic acid, palmitic acid, stearic acid or oleic acid. Examples of the polybasic fatty acid include a dimer acid of oleic acid or linoleic acid having a carbon number of 36, a oleic acid having a carbon number of 54 or a trimeric acid of linoleic acid. The polycondensed hydroxy fatty acid preferably has a carbon number of from 36 to 180, and examples thereof include a hydroxy stearic acid of 2 to 10 molecules. As the polyethylene glycol, a molecular weight of about 1,500 to 2,500 is preferred. As the polyester, a diester can be used, and when possible, a tris, a tetraester or the like can also be used.

The molecular weight of the surfactant must be from 2,000 to 15,000. If it is less than 2,000, the oil particles are inferior in coagulation resistance, and if the molecular weight exceeds 15,000 within the range that the inventors can obtain, the oil solubility is deteriorated. In addition, the HLB of the surfactants must be 5-9. If it is less than 5, the oil solubility becomes strong, and if it exceeds 9, the water solubility becomes strong, and in either case, it cannot be stably present at the interface between the oil particles and water.

The amount of the surfactant to be added is preferably 0.1 part by mass or more, more preferably 1 part by mass or more, further preferably 2 parts by mass or more, and particularly preferably 4 parts by mass or more, based on 100 parts by mass of the base oil. Further, in the present invention, even when 5 parts by mass or more of the surfactant is added, the spreadability can be improved. It is known that when such a surfactant is added, the emulsion stability is good, and on the other hand, the spreadability is poor, and the present invention can coexist. If the amount of the surfactant added is too small, the stability of the emulsification dispersion is poor. In addition, the upper limit is not particularly limited, and is preferably 10 parts by mass or less, more preferably 7 parts by mass or less, and still more preferably 6 parts by mass or less in terms of saturation of the effect of adding a surfactant.

(elastomer)

The metal roll oil composition of the present invention contains an elastomer. Thereby, the metal roll oil composition of the present invention can improve emulsion stability and can improve the spreadability. Thus, it is conventionally known that the emulsification stability and the spreadability of the trade-off relationship can be achieved by the inclusion of the elastomer in the present invention.

The roll oil is used by emulsifying and dispersing in water to form a coolant. The coolant supplied from the nozzle collides with the steel sheet to be coated, and at this time, the emulsified state of the coolant is broken, and only the oil is spread on the metal surface. It is considered that the coolant is continuously supplied and the adhesion and re-washing of the oil are repeated, thereby forming a capping oil film. Here, since the elastomer is insoluble in water, it is present in the oil phase, and the effect of suppressing the fluidity due to the molecular weight thereof and/or the intramolecular bond structure formed by crosslinking hinders the oil film. Wash it again when it is formed. Therefore, it is considered that the spreadability is improved by the inclusion of the elastomer.

The elastomer to be used in the present invention is not particularly limited as long as it is a rubber-like resilient elastomer, and a thermosetting elastomer or a thermoplastic elastomer can be used. Examples of the thermosetting elastomer include natural rubber, urethane rubber, polyoxyethylene rubber, and fluororubber. Further, the thermoplastic elastomer system has a microphase-separated structure including a soft phase and a hard phase, and examples thereof include a styrene-butadiene block copolymer, an isoprene-isobutylene copolymer, an ethylene-propylene copolymer, and polyisobutylene. Wait.

The lower limit of the molecular weight of the elastomer is preferably 30,000 or more by weight, more preferably 50,000 or more by weight, and the upper limit is preferably 6,000,000 or less by weight, more preferably 2.5 million or less by weight. If the molecular weight is too small, there is a problem that the effect of hindering the re-washing of the oil film on the cover is poor. Further, if the molecular weight is too large, the solubility in the base oil is poor.

The content of the elastomer is preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more, further preferably 0.2 parts by mass or more, and the upper limit is preferably 20 parts by mass or less, more preferably 100 parts by mass or less, based on 100 parts by mass of the base oil. 10 parts by mass or less, more preferably 5 parts by mass or less, still more preferably 3 parts by mass or less, and still more preferably 2 parts by mass or less. If the content of the elastomer is too small, the effect of improving the spreadability is reduced, and if the content of the elastomer is too large, the effect is saturated.

(additive)

In the metal roll oil composition of the present invention, in addition to the above components, various known additives such as an oily agent, an extreme pressure agent, an antioxidant, and the like may be added as needed. Examples of the oily agent include stearic acid, oleic acid, linoleic acid, linoleic acid, arachidic acid, behenic acid, sinapic acid, trimellitic acid, palm oil fatty acid, tallow fatty acid, and lard fatty acid. Fatty acids such as soybean oil fatty acid, rapeseed oil fatty acid, and pine oil fatty acid; esterified products of such fatty acids; dibasic acids such as dimer acid. Examples of the extreme pressure agent include phosphate esters such as trialkyl phosphate, dialkyl phosphate, and triaryl phosphate; trialkyl phosphite, dialkyl phosphite, triallyl phosphite, and the like. Phosphite and the like. Examples of the antioxidant include a phenol compound such as di-t-butyl-p-cresol; an aromatic amine such as phenyl _- α-naphthylamine.

<coolant>

The metal roll oil composition of the present invention is obtained by mixing with water and dispersing the mixed solution by a mixer or the like to form a coolant in which a metal roll oil composition is emulsified and dispersed in water. The ratio of the metal roll oil composition in the coolant is usually set to 1 to 10% by volume. The lower limit of the average particle diameter of the oil component in the coolant is preferably 3 μm or more, more preferably 4 μm or more, further preferably 5 μm or more, and the upper limit is preferably 11 μm or less, more preferably 10 μm or less. It is preferably 9 μm or less, and particularly preferably 8 μm or less. If the average particle diameter is too small, the spreadability is poor, and if the average particle diameter is too large, the emulsion stability is poor. The average particle size of the oil component in the coolant is measured by a Coulter counter.

The coolant is used in the same manner as in the prior art, and is sprayed and supplied to a roll or a rolled material while being circulated.

<Example>

<Examples 1 to 9 and Comparative Examples 1 to 7>

The metal roll oil compositions of Examples 1 to 9 were prepared by blending the components shown in Table 1 in specific amounts. Further, the metal roll oil compositions of Comparative Examples 1 to 7 were prepared by blending the respective components shown in Table 2 in specific amounts.

<Preparation of coolant>

Each metal roll oil composition was added to water so as to be 2% by volume, and pump cycle and stirring were performed for 30 minutes using a gear pump (flow rate of 30 L/min) and a homomixer (rotation speed of 3000 rpm) to prepare emulsified dispersion. Liquid (liquid amount: 10 L, liquid temperature: 55 ° C). The average particle size of the metal roll oil composition in the dispersion was measured by a Coulter Counter (Multisizer-II). Next, 200 mL of the dispersion was weighed, and after standing for 30 minutes, the concentration of the sample oil of the lower layer of 100 mL was measured, and the emulsion stability (ESI-30) of the coolant was evaluated. The calculation method of ESI-30 is as follows:

(calculation method of ESI-30)

ESI-30 (%) = [(100 mL sample oil concentration after 30 minutes of standing) / (initial concentration)] × 100

(evaluation of the cover)

The emulsified dispersion obtained above was circulated by a pump for 1 hour, and the emulsified dispersion was sprayed on a vertically suspended test piece for 2 seconds, and the amount of adhered oil (g/m ² ) at this time was measured.

Test piece: SPCC-SD, 1.2 × 60 × 80 mm

Test piece temperature: 120 ° C

Injection flow rate: 2.1 L/min

Sample oil concentration: 2% by volume

Liquid volume: 10 L

Liquid temperature: 55 ° C

Synthetic ester: trade name "Unistar-H-381R", Nippon Oil Co., Ltd.

Surfactant A: trade name "Ionet S-80", Sanyo Chemical Industry Co., Ltd., sorbitan fatty acid ester surfactant

Surfactant B: trade name "Ionet DO-1000", Sanyo Chemical Industry Co., Ltd., polyoxyethylene fatty acid diester

Surfactant C: trade name "Hypermer A60", Croda Japan Co., Ltd., copolymer of butadiene polybutene, polyalkylene glycol and glycerol

Oily agent A: trade name "TOENOL #1050", Dangrong Chemical Co., Ltd., tallow fatty acid; oily agent B: trade name "NAA-35", Nippon Oil Co., Ltd., oleic acid

Antioxidant: trade name "Sumilizer-BHT", Sumitomo Chemical Co., Ltd.

Elastomer-A: Natural rubber (the main body of cis-1,4-polyisoprene, weight average molecular weight is 100,000 to 2.5 million)

Elastomer B: isobutylene rubber (poly(1,1-dimethylethylene), weight average molecular weight of 60,000 to 5 million)

High molecular weight polymer: trade name "Aqualube 702", Sanyo Chemical Industry Co., Ltd., mineral oil solution of alkyl methacrylate-based copolymer. It can be seen from the results of Tables 1 and 2 above that the metal roll of the present invention is used. Among the coolants of the oil composition, the particle size of the coolant is small, the emulsion stability is good, and the spreadability is also good. Although the addition of the high molecular polymer coexists with the emulsion stability and the spreadability, the effect of improving the spreadability is small compared with the case of adding the elastomer, and it is difficult to say that the spreadability is sufficiently excellent (Comparative Examples 6 and 7).

Regardless of the elastomer or the polymer, if the amount of addition is increased, the viscosity of the coolant increases. If the viscosity becomes high, dirt is likely to remain around the roll machine, and the dirt is accumulated.

If the deposit falls on the roll steel sheet, the quality of the roll steel sheet is lowered, so that it is necessary to remove the deposit and increase the load of the subsequent step. In addition, deposits also cause a deterioration in the working environment and the risk of fire. The elastomer exhibits an excellent effect of improving the spreadability in a small amount as compared with the polymer, and thus does not cause the above-mentioned deposit.

The present invention has been described above with reference to the embodiments which are considered to be the most practical and optimal, but the present invention is not limited to the embodiments disclosed in the specification of the present application, and may not contradict the scope of the patent application and the overall specification. The metal roll oil composition and the coolant accompanying such changes must be appropriately changed within the scope of the gist of the invention as understood, and it is necessary to understand that it is included in the technical scope of the invention.

(industrial availability)

The metal roll oil composition of the present invention is used in cold rolling of metal.

Claims (5)

A metal roll oil composition comprising at least one base oil selected from the group consisting of mineral oil, animal and vegetable oils and fats and synthetic esters, a surfactant, and an elastomer. The metal roll oil composition of the first aspect of the invention, wherein the surfactant is contained in an amount of 0.1 part by mass or more and 10 parts by mass or less, and the amount of the above-mentioned surfactant is 0.05 parts by mass or more and 20 parts by mass or less or less per 100 parts by mass of the base oil. The above elastomer. The metal roll oil composition of claim 1 or 2, further comprising an oily agent. A metal roll oil composition according to claim 1 or 2, which further contains an antioxidant. A coolant obtained by dispersing a metal roll oil composition according to any one of claims 1 to 4 in water.