WO2007000822A1

WO2007000822A1 - Friction reducer

Info

Publication number: WO2007000822A1
Application number: PCT/JP2005/011964
Authority: WO
Inventors: Hisao Ishii; Kazuma Sunagawa; Akihiro Oda
Original assignee: Topura Co., Ltd.
Priority date: 2005-06-29
Filing date: 2005-06-29
Publication date: 2007-01-04

Abstract

A friction reducer that is applied to a fastening member to thereby attain reduction of the friction of the fastening member and suppression of any fluctuation of the friction coefficient thereof. In particular, there is provided a friction reducer produced by dispersing and dissolving in water a resin as a film-forming component and a fatty acid metal salt/fatty acid ester as a lubricant component. Specifically, there is provided friction reducer (1) comprising an aqueous resin and a fatty acid metal salt composed of a C8-C30 fatty acid and a metal selected from among an alkali metal, an alkaline earth metal and zinc and, wherein the weight of resin contained is in the range of 0.5 to 3 times that of fatty acid metal salt, and provided friction reducer (2) comprising an aqueous resin, a C9-C38 fatty acid ester and a fatty acid metal salt composed of a C8-C30 fatty acid and a metal selected from among an alkali metal, an alkaline earth metal and zinc, wherein the weight of resin contained is in the range of 0.5 to 3 times that of the sum of fatty acid metal salt and fatty acid ester.

Description

Specification

Friction reducing agent

Technical field

[0001] The present invention reduces friction of a fastening material by being applied to a friction reducing agent, particularly a fastening material, and suppresses variation in a friction coefficient when fastening the fastening material, thereby stabilizing torque management. It is related with the friction reducing agent which implement | achieves.

Background art

[0002] When fastening is performed using a combination of fastening materials such as bolts, washers, and nuts, it is necessary to stably provide the axial force necessary for fastening. For this purpose, the axial force is usually generated while controlling the tightening torque. However, since the axial force generated by the torque changes depending on the mating member and the surface condition of the bolt and nut, it is difficult to manage the torque to stably generate the required axial force. There is a problem. Further, the larger the size of the fastening material or the higher the strength of the fastening material, the higher the required tightening torque. Therefore, there is a tendency that the variation in the axial force generated thereby increases.

[0003] In order to solve such problems, the conventional force is applied by applying organic matter to the fastening material, thereby reducing the required tightening torque (that is, reducing the friction coefficient of the fastening material) and generating the torque. It has been attempted to reduce the variation in axial force. As the organic substance, lubricating oil (for example, mineral oil) is widely used. Further, as the organic substance, a friction coefficient reducing agent for a fastening material containing a synthetic resin or a cocoon is also known. For example, it is miscible with an ether-bonded polymer such as polyethylene oxide or ethylene oxide propylene oxide. Some include synthetic resins (see, for example, Patent Document 1).

[0004] However, since the lubricating oil has weak adhesion strength with the surface of the fastening material to which it is applied (for example, a metal surface), the lubricating oil exhibits its lubricating performance sufficiently when fastening with the fastening material. It is difficult to achieve a predetermined reduction in friction. Furthermore, the friction reducing agent including the ether-bonded polymer described above often has a coating coefficient that is difficult to be uniform due to application spots or the like, and the friction coefficient is not stable when applied to a fastening material. ,. [0005] Further, the above-described lubricating oil or a friction reducing agent containing an ether-bonded polymer body may be applied to a fastening material that has been subjected to a surface treatment that is often surface-treated. Depending on the type of surface treatment applied, the friction coefficient when fastening fasteners often varies greatly.

Patent Document 1: Japanese Patent No. 2984099

Disclosure of the invention

[0006] Based on the above situation, the present inventor

1) Similar to conventional lubricants or friction reducers containing synthetic resins and waxes, it can reduce the friction of fastening materials,

2) It can be applied evenly to the fastening material, and the change in the friction coefficient of the fastening material due to the application method can be suppressed.

3) The friction coefficient of the fastening material can be made constant by the difference in the surface treatment applied to the fastening material.

In order to obtain a friction reducing agent for fasteners with these three characteristics, we have intensively studied. That is, the inventor of the present application examined providing a friction reducing agent having the above three characteristics 1) to 3) by combining a film-forming component and an essential lubricating component.

[0007] Further, the present inventors have studied to provide a fastening material to which such a friction reducing agent is applied, which has reduced friction and can perform appropriate torque management when fastening.

That is, the present invention is as follows.

(1) One or more fatty acid metal salts having a metal power selected from fatty acids having 8 to 30 carbon atoms and alkali metals, alkaline earth metals and zinc, and

A friction-reducing agent for a fastening material obtained by dispersing and dissolving one or more types of rosin selected from a water-soluble synthetic resin and an aqueous synthetic resin in water, wherein the weight content of the rosin is A friction reducer that is 0.5 to 3 times the contained weight.

(2) one or more fatty acid metal salts having a metallic strength selected from fatty acids having 8 to 30 carbon atoms and alkali metals, alkaline earth metals and zinc;

One or more fatty acid esters having 9 to 38 carbon atoms, and

One or more types of rosin selected from water-soluble synthetic resins and aqueous synthetic resins A friction reducing agent for a fastening material, in which water is dispersed and dissolved in water, and the content of the fat is 0.5 to 3 times the total content of the fatty acid metal salt and the fatty acid ester Agent.

(3) A fastening material obtained by applying and drying the friction reducing agent according to (1) or (2).

BEST MODE FOR CARRYING OUT THE INVENTION

[0009] The friction reducing agent for a fastening material according to the present invention is a combination of a fat that can be a film-forming component, a fatty acid metal salt or a fatty acid ester that can be a lubricating component, and the like. Both components can be fixed uniformly and firmly.

That is, one aspect of the friction reducing agent for a fastening material of the present invention includes 1) a fatty acid metal salt and 2) a resin selected from water-soluble synthetic resins and aqueous synthetic resins in an aqueous solvent. Another aspect of the friction reducing agent for a fastening material of the present invention is a resin selected from 1) a fatty acid metal salt, 2) a fatty acid ester, and 3) a water-soluble synthetic resin and an aqueous resin in an aqueous solvent. Including. Furthermore, it may be preferred that the friction reducing agent of the present invention comprises a surfactant. Moreover, the other arbitrary components may be included.

The components 1) to 3) are preferably dispersed and Z or dissolved in an aqueous solvent.

[0010] The fatty acid metal salt contained in the friction reducing agent of the present invention is a salt composed of a fatty acid and a metal. The fatty acid is more preferably a fatty acid having 12 or more carbon atoms, preferably a fatty acid having 8 or more carbon atoms in the molecule from the viewpoint of lubricity and film-forming performance (film-forming property). Also, fatty acids with more than 30 carbon atoms are difficult to obtain and may not be practical.

[0011] The carbon chain of the fatty acid is a straight chain or a branched chain, and may have an unsaturated bond in the carbon chain. Further, an arbitrary substituent (for example, a hydroxyl group) may be present on the carbon chain.

[0012] Examples of preferred fatty acids include octanoic acid, lauric acid, myristic acid, normitic acid, stearic acid, arachic acid, behenic acid, lignoceric acid, serotic acid, montanic acid, melicic acid, oleic acid, linoleic acid, Linolenic acid, isostearic acid, ricinoleic acid, 1,2-hydroxy stearic acid, naphthenic acid, rosin acid, etc. are included. Further preferred examples include saturated fatty acids such as lauric acid, palmitic acid, stearic acid, montanic acid, melicic acid, and Unsaturated fatty acids such as oleic acid are included. Since these metal salts (for example, alkali metal salts) are solid, and solidify the surface of the fastening material stably and uniformly, they can be positively applied to the present invention.

[0013] It should be noted that the fatty acid metal salt in the present invention may be a sarcophagus produced by a fat-and-oil power containing a large amount of the fatty acid, and these can also be suitably used.

[0014] Examples of the metal of the fatty acid metal salt include alkali metals such as lithium, sodium and potassium, alkaline earth metals such as magnesium, calcium and norium, and transition metals such as zinc, lead, tin, copper and bismuth. Is included. Preferably, ecological metals such as alkali metals, alkaline earth metals, and zinc are used from the environmental and cost viewpoints.

[0015] The fatty acid metal salt of the present invention may be a fatty acid metal salt in which the above-described fatty acid and metal are arbitrarily combined. An example is calcium stearate. One of these fatty acid metal salts can be used alone, or a combination of several can be used.

[0016] The fatty acid ester contained in the friction reducing agent of the present invention is preferably one that is frequently used as a main component of a plastic working lubricating oil, that is, one having a lubricating performance due to metal adsorption. Fatty acid esters having a small number of carbon atoms are not practical because they tend to have poor solvent properties and poor film-forming properties due to their strong solvent properties. Therefore, the number of carbon atoms in the molecule of the fatty acid ester is preferably 9 to 38 (more preferably 13 to 36). On the other hand, fatty acid esters having 39 or more carbon atoms in the molecule may be difficult to obtain and may not be practical.

[0017] Examples of the fatty acid ester include dehydration condensation of a linear fatty acid having 8 or more carbon atoms, a linear alcohol such as methanol and octanol, and a branched alcohol such as 2-ethylhexanol. The resulting ester is included. Of these, saturated fatty acid esters (for example, myristyl myristate) are more preferred because they have a film-forming property. In addition, unsaturated fatty acid esters (for example, methyl oleate) are preferable from the viewpoint of imparting appropriate fluid lubricity to the formed film and reducing friction.

[0018] Further, the fatty acid ester is preferably a fatty acid ester that forms a high melting point film. Specifically, beef tallow oil, carnavic acid ester, montanic acid ester, etc. Is exemplified.

[0019] Further, as the fatty acid ester, hindered esters of alcohols having a neo-type molecular structure such as neopentyl alcohol, trimethylolpropane, pentaerythritol and the like can be used.

[0020] The fatty acid ester contained in the friction reducing agent of the present invention may be a single type of fatty acid ester or a combination of a plurality of types of fatty acid esters.

[0021] The water-soluble synthetic resin or aqueous synthetic resin contained in the friction reducing agent of the present invention is preferably used as a film-forming component for fixing the fatty acid metal salt and the fatty acid ester to the surface of the fastening material. As the water-soluble synthetic resin or water-based synthetic resin, many commercially available ones can be applied, and the form and type are not restricted.

[0022] The water-soluble synthetic resin or the water-based synthetic resin may be obtained by using a solvent (organic solvent or water) or without using a solvent for solution polymerization, suspension polymerization, emulsion polymerization, bulk polymerization, or the like. These are synthetic resins produced by complex polymerization.

[0023] The water-soluble synthetic resin means a resin containing an aqueous polymer such as PVA (polybulal alcohol), CMC (carboxymethyl cellulose), PEO (polyethylene oxide) and the like.

[0024] Examples of the water-based synthetic resin include those obtained by subjecting the synthetic resins exemplified in the following 1 to 6 to water-based treatment or dispersing them in water with a surfactant. That is, examples of the water-based synthetic resin include water-dispersible hydrosols, water-dispersible emulsions, emulsions and dispersions dispersed in an aqueous solvent with a surfactant.

[0025] 1. Orthophthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, adipic acid, sebacic acid, trimellitic acid, or an anhydride thereof and a polyhydric alcohol (glycerin, pentaerythritole, trimethylolethane, Long oil and short oil alkyd coconut oil obtained by condensation reaction of trimethylolpropane, neopentyl glycol, 1,4 cyclohexane dimethanol, sorbitol, etc.) and modified with natural oil or fatty acid. Alternatively, a modified alkyd resin combining the alkyd resin and a urea resin or melamine resin.

2. Polymerize acrylic monomers (eg acrylic acid, methyl methacrylate, tert-butyl methacrylate, i-butyl methacrylate, methyl acrylate, butyl acrylate, acrylic acid-2-ethylhexyl, etc.) Acrylic greaves with Djibouti as needed Acrylic resin containing ruphthalate, dioctyl phthalate, diisonol phthalate, diisodecyl phthalate, didecyl phthalate, mixed alkyl phthalate as plasticizer.

3. An acrylic styrene resin obtained by copolymerizing the above acrylic monomer and styrene monomer.

4. Acrylic modified alkyd resin or styrene modified acrylic alkyd resin obtained by adding acrylic polymer or acrylic styrene polymer to alkyd skeleton (alkyd polymer).

5. Urethane alkyd resin obtained by reacting the free hydroxyl group of a mixture of mono- and diglycerides of dry oil (eg flaxseed oil) with diisocyanate.

6. Epoxy resin obtained by condensation polymerization of epichlorohydrin and diphenol-rollpropane.

[0026] In the above-described aqueous treatment of acrylic resin alkyd resin, for example, when these resins are produced, free acidic or basic functional groups are introduced into the polymer main chain. It can be carried out by neutralizing the functional group with an acid or alkali (for example, jetylamine, triethylamine, diethanolamine, triethanolamine, ammonia, etc.) and the like and introducing a hydrophilic group into the molecule. By this aqueous treatment, it is easy to disperse in water.

[0027] The above-described aqueous treatment of epoxy rosin includes 1) reacting with maleic fatty acid to open an epoxy ring to generate a hydroxyl group, or 2) liberating by reacting with fatty acid. This can be done by forming a carboxylic acid group and then neutralizing with a suitable base. The water-based treatment can facilitate the dispersion in water.

[0028] As the "water-soluble synthetic resin or water-based synthetic resin" included in the present invention, one kind of the above-mentioned resin may be used alone, or a plurality of kinds may be used in combination.

[0029] As described above, the friction reducing agent of the present invention may contain a surfactant. By including the surfactant, the surface activity of water in the friction reducing agent can be reduced, and the wettability to the metal surface and the uniform coating property can be improved. Further, when the fatty acid metal salt contained in the friction reducing agent is a strong alkaline earth metal fatty acid salt, a surfactant is preferably included. This is because the alkaline earth metal fatty acid salt is difficult to disperse in water, and therefore it is preferable to improve the dispersibility with a surfactant.

[0030] As the surfactant, the dispersibility of the fatty acid metal salt is improved, and the uniform coating property is improved. As long as it contributes to improvement, any of surfactants of non-one type, er-on type, cationic type, and amphoteric can be used. Examples thereof include fatty acid polyhydric alcohol esters, polyoxyethylene alkyl ethers, higher fatty acid metal salts, alkylbenzene sulfonates, aliphatic amine salts, carboxybetaine types, and the like. Also, you can use one of these surfactants alone or in combination of two or more. However, since nonionic surfactants have strong properties to promote wrinkling and have foaming properties, the amount of addition may be limited to some extent, so care must be taken.

[0031] The friction reducing agent of the present invention may further contain an optional component. Examples of optional components include pigments, antifungal agents, ultraviolet absorbers, anti-aging agents and the like. In particular, by adding a pigment, the film formed on the fastening material can be colored, thereby confirming whether a film is formed on the fastening material and measuring the thickness of the film. It becomes easy.

[0032] The friction reducing agent of the present invention uses an aqueous solvent as a solvent. Since water can function as a dispersant, it is preferable that the water has low hardness from the viewpoint that it is preferable not to inhibit the stability and dispersibility of the solute in water. However, it can be suitably used if it has a hardness comparable to that of normal tap water.

[0033] As described above, in the friction reducing agent of the present invention, the water-soluble synthetic resin or the water-based synthetic resin (hereinafter collectively referred to as “water-based resin”) is a film-forming component. As a result, the fatty acid metal salt and the fatty acid ester can be fixed on the surface (preferably the metal surface) of the fastening material. On the other hand, since the surface of the fastening material on which the film is formed by the aqueous resin is higher in friction than the surface of the fastening material coated only with the fatty acid metal salt and the fatty acid ester, It can act as a friction-increasing component that reduces the “effect of reducing friction”. Accordingly, it is preferable to contain the aqueous resin in a range that does not offset the friction reducing performance (high lubricating performance) of the fatty acid metal salt and the fatty acid ester.

[0034] From the above viewpoint, the ratio of the total weight of the fatty acid metal salt and fatty acid ester contained in the friction reducing agent of the present invention to the weight of the water-based resin is (fatty acid metal salt + fatty acid ester): (water-based resin) = 1: 0.5 to about 1: 3, more preferably about 1: 1.8 to 1: 2.2 Favored ,. If the aqueous resin is 3 times or less of the total of the fatty acid metal salt and the fatty acid ester, the friction reducing performance of the fatty acid metal salt is hardly offset by the aqueous resin. On the other hand, if the water-based resin is 0.5 times or more of the total of the fatty acid metal salt and the fatty acid ester, the fatty acid metal salt and the fatty acid ester are fixed (fixed) on the surface of the fastening material, and the friction reducing agent is immediately uniformed. It can be applied to the surface, and the fluctuation of the friction coefficient due to the application method and the fluctuation of the friction coefficient due to the difference in the surface treatment applied to the fastening agent can be suppressed. These effects are also described in the following examples.

[0035] The total content of the water-based rosin, the fatty acid metal salt, and the fatty acid ester contained in the friction reducing agent of the present invention is preferably 5% by weight or more based on the entire friction reducing agent. If the content thereof is small, the thickness of the film formed by applying the friction reducing agent may not be sufficient, and the predetermined reduction in the friction coefficient may not be achieved. On the other hand, it is preferable that the total content of water-based resin, fatty acid metal salt, and fatty acid ester is 20% by weight or less based on the entire friction reducing agent. When the content is large, the film thickness of the coating formed on the surface of the fastening material becomes excessive. A film with an excessive film thickness generates resistance when fastening the fastening material, making it difficult to secure a stable coefficient of friction, and fastening that can be applied per fixed amount of friction reducing agent. The number of materials is reduced, which is not preferable in terms of cost.

[0036] The weight ratio of the fatty acid metal salt and the fatty acid ester contained in the friction reducing agent of the present invention may be any ratio.

[0037] When the friction reducing agent of the present invention contains a surfactant, the content of the surfactant is, as described above, from the viewpoint of improving the dispersibility of the fatty acid metal salt and improving the uniform coating property. The content is preferably 0.1 to 5% by weight based on the entire friction reducing agent.

[0038] The friction-reducing agent of the present invention is a fatty acid metal salt, an aqueous resin, a fatty acid ester, and optionally a surfactant in a solvent containing water at room temperature in any order. It can be manufactured by blending and stirring other ingredients. In addition, the fatty acid metal salt to be blended is preferably dispersed in water or dissolved in water by stirring separately with a surfactant as necessary.

[0039] The friction reducing agent of the present invention is used by being applied to a fastening material. Friction of the present invention The fastening material coated with the reducing agent reduces friction and the friction reducing agent is applied uniformly, so that the friction coefficient does not fluctuate extremely depending on the application method. Variations in the coefficient of friction due to different surface treatments are also suppressed. As a result, when fastening is performed using the fastening material, it can be fastened with a low torque, and the axial force generated by the torque is constant. These effects are also explained in the following test examples and examples.

[0040] The fastening material to which the friction reducing agent of the present invention is applied is a member used for fastening members such as bolts, nuts, and washers. The material of the fastening material is a metal, preferably a metal such as steel, stainless steel, aluminum, brass, or a force, preferably a metal.

[0041] The surface of the fastening material of the present invention may be subjected to any surface treatment, for example, a chromate treatment after electrozinc plating or a surface treatment such as dumbbell chromium oxidation treatment. The friction reducing agent of the present invention can make the friction coefficient of the fastening material constant regardless of the difference in the surface treatment applied to the fastening material.

[0042] As a method of applying the friction reducing agent of the present invention to the fastening material, any method can be adopted, and it may be appropriately selected according to the kind of the fastening material. For example, 1) dip coating, 2) spray coating, 3) brush coating and the like are preferably exemplified. Also, any means can be used for drying after coating, and preferable examples include, for example, room temperature standing drying, heating tank standing drying, and warm air blowing. Further, a centrifugal operation may be used in combination to remove the excessively applied agent. If bolts and nuts are used as the fastening material, a friction reducing agent may be applied to both, but apply to either one (for example, bolts).

[0043] Hereinafter, the present invention will be further described with reference to test examples and examples. However, these are examples of the present invention and do not limit the scope of the present invention.

[0044] <Test Example 1>

According to the composition of Table 1 below, Samples 1 to 14 containing acrylic alkyd rosin, which is a water-based rosin, sodium stearate, which is a fatty acid metal salt, and carnavic acid ester, which is a fatty acid ester, were prepared. In addition, all units are% by weight, and the remainder is all water. [0045] Each sample was prepared by adding, in order, water-based rosin, fatty acid metal salt, and fatty acid ester in water.

[0046] Further, acrylic monoalkyd resin used in Test Example 1 is “triethanolamine neutral product of copolymer of attalic acid, methacrylic acid, styrene and alkyd polymer”. It is. More specifically, 1 mol of styrene is added to 1 mol of acrylic acid, the carboxyl group of atalic acid is neutralized with 1 mol of triethanolamine, and the terminal of acrylic acid is combined with a methacrylic acid monomer. This resin has a structure that is polymerized and grafted onto alkyd resin with 1 mole of oleic acid.

In addition, sodium stearate used in Test Example 1 was dissolved in water by stirring with a surfactant (polyoxyethylene stearyl ether (EO: 10 mol addition)).

[0047] [Table 1]

[0048] In this test example, a fastening measurement using a fastening material and a to-be-clamped plate was performed. The effects of the samples 1 to 14 prepared according to the compositions shown in Table 1 as a friction reducing agent were verified.

[0049] In this test example, as a fastening material,

Strength category of thread size M10, thread pitch 1.25 8. 8 flanged hexagon bolts, bolts colored with chromate after electrozinc plating, or bolts with zinc powder chrome oxidation treatment (both of these treatments prevent This is a process aimed at dredging), and Use nuts of the same size as the bolts above, and colored chromate treated after electrozinc plating o

The plate to be clamped was a plate clamped made of cold-pressed steel plate (SPCC).

[0050] Samples 1 to 14 prepared in accordance with Table 1 were dip-coated on the bolts that had been subjected to electrochromic plating and colored chromate treatment or zinc powder chrome oxidation treatment, respectively, and were excessively removed using a centrifuge. After removing the coating liquid, it was dried with warm air. Tightening measurement was performed using the bolt thus obtained, the nut, and the plate to be tightened, and the coefficient of friction was determined according to the following equation.

[0051] [Equation 1]

2T / F-ρ / π

β set (I)

T: Tightening torque (N · m) F: Axial force (k N)

Screw pitch (mm) π: Circumference ratio: Effective screw diameter (mm) Half of the thread angle (rad)

d w: Constant obtained from the seat surface outer diameter and seat surface inner diameter of the bolt equivalent head (mm)

[0052] The above dw can be obtained according to the calculation formula described in JIS B1084, specifically, the following calculation formula (II).

[0053] [Equation 2]

Formula (II)

d ₁ : Bolt bearing surface diameter d H: Bolt hole diameter

[0054] Five tests were repeated for each test. Table 2 shows the results obtained. In Table 2, the minimum and maximum values mean the minimum and maximum friction coefficients obtained in five repeated experiments, and the average value means the friction coefficient obtained in five repeated tests. of Average value.

[0055] [Table 2] Colored chromate after electrozinc plating Zinc powder chromium oxidation treatment

Processed Porto Porto Average Value Minimum Value Maximum Value Average Value Minimum Value Maximum Value Average Difference Sample 1 0. 238 0. 256 0. 248 0. 272 0. 294 0. 288 0 040 Sample 2 0. 230 0. 249 0. 238 0. 263 0. 281 0. 268 0 030 Sample 3 0. 165 0. 188 0. 183 0. 1 Huff 0. 189 0. 186 0 003 Sample 4 0. 156 0. 180 0. 174 0. 162 0. 179 0. 175 0 001 Sample 5 0. 130 0. 138 0. 134 0. 125 0. 141 0. 133 0 001 Sample 6 0. 167 0. 179 0. 170 0. 145 0. 152 0. 148 0 022 Sample 0. 242 0. 258 0. 248 0. 185 0. 196 0. 190 0 058 Sample 8 0. 252 0. 270 0. 261 0. 230 0. 250 0. 244 0 017 Sample 9 0. 121 0. 143 0. 128 0. 134 0. 140 0. 132 0 004 Sample 10 0. 164 0. 175 0. 171 0. 162 0. 178 0. 173 0 002 Sample 11 0. 175 0 194 0. 182 0. 204 0. 221 0. 215 0 033 Sample 12 0. 191 0. 222 0. 210 0. 227 0. 252 0. 238 0 028 Sample 13 0. 163 0. 186 0. 177 0 175 0. 194 0. 188 0 011 Sample 14 0. 148 0. 169 0. 154 0 168 0 .74 0. 171 0 017

[0056] As is clear from Table 1 and Table 2, it is understood that the average value of the friction coefficient when using the bolts coated with Samples 4 to 6, 9 to 10, and 14 is 0.180 or less. . All of these samples have an aqueous resin content in the range of about 0.5 to 3.0 times the total content of fatty acid metal salt and fatty acid ester.

[0057] Samples 4 to 5 and 9 to 10 have very small fluctuations in the friction coefficient due to the difference in the surface treatment applied to the bolt (colored chromate treatment or zinc powder chrome oxidation treatment)!ヽ It is powerful (the average difference is 0.001-0.004). For Samples 6 and 14, the variation is relatively small (average of about 0.02). From these results, it is found that the friction reducing agent in which the content weight of the aqueous resin is 0.5 to 3.0 times the total content weight of the fatty acid metal salt and the fatty acid ester reduces the friction coefficient of the fastening material. It can be seen that the friction coefficient can be kept constant regardless of the surface treatment applied to the fastening material.

In Test Example 2, a friction reducing agent was prepared according to the composition shown in Examples 1 to 4 below. . In addition, Comparative Examples 1 to 3 were prepared.

[0059] Example 1

Calcium stearate 3.7 wt ^_0/0

Surfactant 0.1% by weight

Aqueous acrylic alkyd resin 7.2% by weight

89.0% by weight of water

Example 2

Sodium stearate 2.8 weight ^_0/0

Aqueous acrylic styrene resin 5.2% by weight

Water 92.0% by weight

Example 3

Sodium Orein acid 4.0 weight ^_0/0

Water-based acrylic alkyd rosin 8.0% by weight

Water 88.0% by weight

Example 4

Calcium stearate 1.0 wt ^_0/0

Carnauba acid Echiruesuteru 3.0 weight ^_0/0

Surfactant 0.1% by weight

Water-based acrylic alkyd rosin 8.0% by weight

Water 87.9% by weight

In the above examples, the surfactant used is polyoxyethylene stearyl ether (EO: 10 mol addition) which is a nonionic surfactant.

Further, the acrylic alkyd resin used in Examples 1, 3 and 4 is the same as the acrylic alkyd resin used in Test Example 1.

The acrylic monostyrene resin, which is an aqueous resin used in Example 2 above, is one in which styrene is introduced into the allyl chain.

In addition, the fatty acid metal salt (calcium stearate) used in Examples 1 and 4 is a surfactant (polyoxyethylene stearyl ether (EO: 10 mol addition)). Used, a stirring process is incorporated and water is dissolved.

[0061] Comparative Example 1

No treatment (Do not treat the friction reducer on the bolt! ヽ)

Comparative Example 2

Machine 10 (Oil JIS K2238 ISO VG 10)

Comparative Example 3

Commercial water-based wax-containing coating (high melting point polyethylene wax)

[0062] In Test Example 2, the same fastening materials (bolts and nuts) and clamped plates as in Test Example 1 were used, and the bolts were colored chromate or zinc powder after electrogalvanizing treatment as in Test Example 1. Chromium oxidation treatment was performed.

[0063] The agents of Examples 1 to 4 and Comparative Examples 2 to 3 were dip coated on the colored chromate-treated or zinc powder chrome oxidation-treated bolt, and the excess coating solution was removed using a centrifuge. And dried with warm air. Further, in Comparative Example 1, a bolt not having such application was used. The bolts and the nuts thus obtained were tightened on the plate to be tightened and measured for tightening, and the friction coefficient was determined according to the above formula (I).

[0064] Five tests were repeated for each test. The results obtained are shown in Table 3. Note that the maximum and minimum values mean the maximum and minimum friction coefficients obtained in five repeated experiments, and the average value is the average value of the friction coefficients obtained in five repeated experiments. Is

[0065] [Table 3]

As is apparent from Table 3, the average friction coefficient obtained by tightening measurement using a bolt without treatment with the agent as in Comparative Example 1 is 0.3 or more. Also minimum The difference between the value and the maximum value is 0.063 and 0.048, and the difference between the average values of the friction coefficients due to the difference in surface treatment is 0.037.

[0067] On the other hand, the coefficient of friction obtained by tightening measurement using the bolt processed by machine 10 which is the machine oil of Comparative Example 2 is 0.22 or less on average regardless of the difference in surface treatment. Compared with Comparative Example 1 (untreated product), it can be seen that the friction is reduced to some extent. Also, the difference between the minimum and maximum values is 0.016 and 0.027, and the difference between the average values of the friction coefficients due to the difference in surface treatment is 0.028. In both cases, blurring is suppressed to some extent!

In addition, the friction coefficient obtained by tightening measurement using the bolts treated with the commercial water-based wax of Comparative Example 3 is an average value of 0.17 or less regardless of the difference in surface treatment. It can be seen that the friction is further reduced. However, the difference between the minimum and maximum values is 0.035 and 0.036, which is larger than Comparative Example 2, and the difference in friction coefficient due to the difference in surface treatment is 0.026. It turns out that it has not improved much.

[0068] On the other hand, the tightening measurement force using the bolts coated with the agents of Examples 1 to 4 were all less than 0.170, and compared with any of Comparative Examples 1 to 3. It can be seen that the friction is reduced. It can also be seen that the difference between the minimum and maximum friction coefficients in each measurement is as small as 0.013 at the maximum, and the friction coefficient fluctuation due to coating is small. Furthermore, the difference in the average value of the friction coefficient due to the difference in the surface treatment is also suppressed to 0.001-0.003 (difference in the average value), indicating that the friction coefficient is extremely stable.

[0069] From these results, the friction reducing agent of the present invention is uniformly applied to the fastening material,

1) Achieved low friction of the fastening material,

2) Friction coefficient fluctuation due to the application method can be reduced,

3) The fact that the friction coefficient can be made constant regardless of the difference in the surface treatment applied to the fastening material is impressive.

Industrial applicability

[0070] The fastening material coated with the friction reducing agent of the present invention has reduced friction and generates a stable friction coefficient when fastened, regardless of the difference in surface treatment. So book By using the fastening material to which the friction reducing agent of the invention is applied, it is possible to perform fastening while performing appropriate torque management.

Claims

The scope of the claims

[1] One or more fatty acid metal salts comprising a fatty acid having 8 to 30 carbon atoms, an alkali metal, an alkaline earth metal, and a zinc selected metal, and

[2] One or more fatty acid metal salts composed of a fatty acid having 8 to 30 carbon atoms, an alkali metal, an alkaline earth metal, and a metal whose zinc power is also selected,

One or two or more fatty acid esters having 9 to 38 carbon atoms, and one or two or more types of fatty acids selected from water-soluble synthetic resins and aqueous synthetic resins are dispersed and dissolved in water. A friction reducing agent, wherein the weight content of the resin is 0.5 to 3 times the total weight of the fatty acid metal salt and the fatty acid ester.

[3] A fastening material obtained by applying and drying the friction reducing agent according to claim 1 or 2.