JPH0666308A - Self-locking member and its manufacture - Google Patents

Abstract

PURPOSE:To provide a self-locking member suppressing the outflow of a composi tion layer and excluding stickiness by forming an anaerobic hardening composi tion layer on the screw face of a screwing member, and covering this layer with a water-insoluble layer, i.e., a water-nonsuluble sol film layer. CONSTITUTION:A bolt 1 is dipped in a container 5 filled with a liquid material 6 containing metal ions, and the liquid material 6 is brought into contact with a sol film layer forming liquid material to form a water-nonsoluble sol film layer 7. The liquid material 6 is a mixed water solution of calcium chloride and formaldehyde, and the formed sol film layer 7 is a calcium alginic acid film. A composition layer 3 formed on the screw face 2 of the bolt 1 is covered with the sol film layer (water-insoluble layer) 7, and a self-locking member 8 is obtained after drying at the ordinary temperature.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to, for example, screws, bolts,
TECHNICAL FIELD The present invention relates to a self-locking member that can apply a bonding agent in advance to a screwing surface (tightening portion) of a screwing member such as a nut so as to prevent loosening and sealing at the time of tightening, and a manufacturing method thereof.

[0002]

2. Description of the Related Art Self-locking members of this type are usually
By applying a composition comprising a microcapsule containing an adhesive in advance on a screwing surface of a screw member such as a screw, a bolt or a nut, a reaction initiator and a binder for fixing them to a tightening portion (screwing surface). Composed.

As an adhesive composition used here, for example, an adhesive composition comprising a microcapsule containing an acrylic acid ester monomer, an epoxy resin and the like and a curing agent thereof is known.

[0004]

Known adhesives encapsulated by microcapsules can be roughly classified into epoxy and acrylic adhesives as described above.

In an acrylic adhesive, the reaction is isolated by encapsulating one or two of an acrylic monomer, a polymerization initiator and a polymerization accelerator.

[0006] In the epoxy adhesive, the reaction is isolated by encapsulating only the epoxy resin among the epoxy resin, the polymerization initiator, and the polymerization accelerator or by encapsulating the other two.

All of these adhesive compositions need to be prevented from flowing out when they are pre-coated on the screwing surface and fixed on the screwing surface, and therefore they must be solid in appearance.

Therefore, it has been necessary to enclose the liquid component in a microcapsule in advance, or to mix a large amount of a filler and a binder without encapsulating the liquid component in order to prevent runoff and stickiness.

Further, the known microcapsule type adhesive composition of this type has the following problems. 1) When applying to the screwing surface, a troublesome process of diluting the adhesive composition with an organic solvent and applying and drying is necessary, and the use of the solvent causes contamination of the working environment.

2) At the time of microencapsulation, the viscosity and properties of the adhesive are limited. That is, the adhesive must have a low viscosity and be water insoluble. Also,
Avoid polymerization inside the capsule.

In addition to the above, as a method of fixing the adhesive itself on the screwing surface, it is conceivable to select an adhesive that does not flow in a normal state. That is, the fixing of the adhesive to the screw can be achieved even by using the hot melt adhesive.

However, the adhesive used here also has the limitation that it is heat-welding. In addition, the effect of preventing loosening cannot be expected in a system in which hardening does not occur after tightening like a hot melt adhesive.

Further, in order to generate the locking force by the hot melt resin, heat is applied to the screwing surface of the screw or the nut, but this will deteriorate the corrosion resistance of the plating film coated on the screw at a high temperature. Also, the time required for heating becomes inconvenient for work even if the heat is not high.

Therefore, an object of the present invention is to form an anaerobic curable composition layer on the screwing surface of a screwing member and cover the composition layer with a water-insoluble layer to eliminate the use of a binder. SUMMARY OF THE INVENTION It is an object of the present invention to provide a self-locking member and a method for manufacturing the self-locking member, in which the drawbacks existing in the known art are improved.

[0015]

To achieve the above object, according to the self-locking member of the present invention, a polymerizable (meth) acrylic acid ester monomer and a polymerizable monomer are formed on the screwing surface of the screwing member. An anaerobic curable composition layer comprising an oxide polymerization initiator is formed, and the composition layer is covered with a water-insoluble layer.

Further, in order to achieve the above object, according to the manufacturing method of the present invention, the following (a), (b) and (c)
It is characterized by comprising the steps of. (A) a step of forming an anaerobic curable composition layer comprising a polymerizable (meth) acrylic acid ester monomer and a peroxide polymerization initiator on the screwing surface of the screw member, (b) the (a) On the surface of the composition layer formed by the step, a step of applying a sol film layer forming liquid substance capable of gelling with metal ions,
(C) A step of forming a water-insoluble sol coating layer by contacting a liquid substance containing metal ions with the sol coating layer forming liquid material applied in the step (b).

[0017]

DETAILED DESCRIPTION OF THE INVENTION The present invention is described in detail below. The present invention firstly describes an anaerobic curable composition comprising a polymerizable (meth) acrylic acid ester monomer and a peroxide polymerization initiator in a tightening portion (screwed surface) of a screw member such as a screw, a bolt or a nut. The layer is formed by means such as coating.

Examples of the above-mentioned polymerizable (meth) acrylic acid ester monomer include mono- to polyfunctional (meth) acrylic acid esters, and typical examples thereof include:
For example, trimethylolpropane (meth) acrylate, neopentyl glycol di (meth) acrylate,
Examples thereof include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl acrylate, polyethylene glycol di (meth) acrylate, cyclohexyl methacrylate, and bisphenol A type di (meth) acrylate.

Specific examples of the peroxide polymerization initiator include organic hydroperoxides, and typical examples thereof include benzoylcumene-hydroperoxide peroxide and t-butyl-hydroperoxide. , Methyl ethyl ketone hydroperoxide, etc. The amount used is 0.1 to 5% by weight based on the weight of the polymerizable (meth) acrylic acid ester monomer.

Further, the above-mentioned anaerobic curable composition layer according to the present invention may optionally contain a polymerization accelerator. This polymerization accelerator is for promoting the polymerization of the anaerobic curable composition to obtain a desired curing rate, and representative examples thereof include amines such as primary, secondary or tertiary amines. Particularly preferred are tertiary amines. As the tertiary amine, tributylamine, triethylamine,
There are N · N-dialkylallylamine and the like, and secondary and primary amine bets include pyrrolidine piperazine and the like, and in addition, organic sulfimides are also used.

Further, in the present invention, a slight amount of a polymerization inhibitor, a chelating agent, a thixotropic agent,
You may use it in the range which does not produce a reverse effect with respect to an anaerobic composition, such as a plasticizer and a coloring agent (dye).

A dipping method, a brush coating method, or a spray coating method is used as a method for applying the anaerobic curable composition to the screwing surface. When the composition has a high viscosity, it is discharged from a nozzle. The method of making is suitable. The viscosity of the anaerobic curable composition is usually several tens to several tens of thousands cps, and an appropriate coating method may be selected in view of the viscosity and the thixotropic property. For example, when the viscosity is 1000 cps or less and the thixo ratio is relatively small, a spray coating method or a dipping method may be used.

In the present invention, the composition layer formed on the screwing surface of the screwing member as described above is then covered with the water-insoluble layer.

The water-insoluble layer is coated by applying a sol film layer-forming liquid substance capable of gelling with metal ions to the surface of the composition layer, and contacting this substance with a liquid substance containing metal ions. This is done by forming a sol film layer.

To apply the above-mentioned liquid substance for forming a sol film layer onto the surface of the composition layer, for example, the liquid substance is filled in a container having an arbitrary shape, and the screw member on which the composition layer is formed is dipped therein. By doing.

Further, the contact of the applied liquid substance with the liquid substance containing the metal ions is also performed by filling the liquid substance in a container of an arbitrary shape and applying the liquid substance to the container, as described above. The water-insoluble sol film layer is formed by immersing the screw-engaged member and gelling it.

The sol coating layer forming liquid substance mentioned above is capable of forming a water-insoluble sol coating layer by contacting with metal ions such as calcium to form a water-insoluble sol coating layer. Specifically, it is an alkali metal alginate or ammonium salt. , Alkali metal or ammonium pectate, alkali metal or ammonium polyacrylate, carboxymethyl (or ethyl) cellulose alkali metal or ammonium salt, silicic acid alkali metal salt, and the like, and further, alginic acid alkali metal or ammonium salt and gelatin. , A composite layer of alkali metal or ammonium salt of pectic acid with gelatin, a composite layer of alkali metal or ammonium salt of polyacrylic acid with gelatin, carboxymethyl (or ethyl) cellulose alkali metal or ammonium salt and gelatin Composite layer with Chin, a composite layer such as with alkali metal silicate and gelatin.

Hereinafter, the present invention will be described more specifically with reference to the accompanying drawings. FIG. 1 is a partial side view of a bolt used in the present invention, in which a threaded surface (tightening portion) 2 of the bolt 1 is shown.
Then, the composition layer 3 is formed by means such as coating. Although any means may be used for this coating method, it is possible to form a water-insoluble layer on this coating layer so that the composition can be uniformly and evenly attached, and as described later. Thus, it is important to adjust the viscosity and thixo ratio.

FIG. 2 is a cross-sectional view showing a coated state of the sol coating layer forming liquid substance. The bolt 1 of FIG. 1 is dipped in a container 5 filled with the sol coating layer forming liquid substance 4 to thereby The liquid substance 4 is applied to the surface of the composition layer 3.

The sol film layer forming liquid substance 4 shown in FIG.
For example, it is a mixed aqueous solution containing 5% sodium alginate and 3% gelatin. Incidentally, in order to apply the sol film layer forming liquid substance to the surface of the composition layer, spray coating or the like may be used in addition to the dipping method.

FIG. 3 is a sectional view showing the state of formation of the water-insoluble sol coating layer. The bolt 1 of FIG. 2 is dipped in a container 5 filled with a liquid substance 6 containing metal ions to form a liquid substance. 6 is contacted with a sol film layer forming liquid substance to form a water-insoluble sol film layer 7 as shown in FIG. In this case, the liquid substance 6 is a mixed aqueous solution of calcium chloride and formaldehyde, and the formed sol film layer 7 is a calcium alginate film.

As a result, the composition layer 3 formed on the threaded surface 2 of the bolt 1 is coated with the sol film layer (water-insoluble layer) 7, dried at room temperature, and then the self-invention shown in FIG. The locking member 8 is obtained.

As the metal ions for forming a water-insoluble sol film, in addition to calcium, magnesium,
Aluminum, iron, and copper can be used, but when used as an aqueous solution, specific examples include calcium lactate, calcium chloride, magnesium chloride, potassium carbonate, potassium phosphate, aluminum chloride, iron chloride, copper chloride and the like.

To improve the film strength of the sol coating layer 8 (calcium alginate film), the liquid substance 4 shown in FIG. 2 is added with gelatin or gum arabic together with sodium alginate, and the liquid substance containing metal ions shown in FIG. 3 is added. By adding an aldehyde such as formalin together with 6 to the aqueous solution of calcium chloride, it is possible to control the strength (flexibility) of the calcium alginate film by utilizing the reaction between gelatin and the aldehyde.

The viscosity of the aqueous solution in which the film components shown in FIG. 2 are dissolved is preferably 10000 cP or less, more preferably 2000 cP or less in order to obtain an optimum film. Therefore, it is preferable that the amount of sodium alginate is 0.1 part to 20 parts by weight, preferably 0.5 part to 5 parts by weight to prepare an aqueous solution.

In addition to the above-mentioned gelatin or gum arabic, a water-soluble polymer or an emulsified resin can be used as an auxiliary component of the film. The purpose of these film formation auxiliary components is to obtain the flexibility and strength of the film after the film formation, and it may be a plasticizer (so long as it is water-soluble). Examples include alcohol, vinyl acetate emulsion, glycerin, and hydroxyethyl (meth) acrylate.

These film-forming auxiliary components are used by appropriately adding them to an aqueous solution of sodium alginate. However, considering that these auxiliary components may contaminate the calcium chloride aqueous solution when immersed in the calcium chloride aqueous solution to form a film, the film forming auxiliary components previously added to the sodium alginate aqueous solution were added to the calcium chloride aqueous solution. It is preferable to add the same amount.

In the present invention, a surfactant may be added to the liquid substance in order to improve the wettability of the liquid substance (sodium alginate aqueous solution) to the adhesive layer or the sealant layer.

In the precoat bolt (self-locking member) according to the present invention, the composition layer basically maintains a liquid state inside the water-insoluble sol film layer (calcium alginate film).

Usually, when the liquid state adhesive composition is applied as it is, the adhesive composition may flow out over time, or the bolts may be contaminated during transportation due to the contact of the bolts with each other. Specifically, if the liquid material is applied as it is, the tackiness may be hindered due to stickiness, and the present invention can be said to be a cello flocking member in which such drawbacks are improved.

[0041]

The self-locking member (pre-coated bolt) according to the present invention is formed by wrapping the anaerobic curable composition layer inside the water-insoluble sol film layer (calcium alginate film). Therefore, at the time of tightening, the film is broken and the encapsulated anaerobic curable composition flows out, is cut off from the air to be in an anaerobic state, and polymerization is started to enable the tightening of the tightening member. Furthermore, in the manufacturing process, the composition does not need to be diluted with a solvent and can be simply manufactured.

Further, it is considered that the anaerobic curable composition used in the present invention usually undergoes curing when in contact with a metal bolt. However, in order to cause anaerobic curing of the anaerobic curable composition, it is essentially necessary to completely block the air. Conversely, if air is distributed, anaerobic curing is prevented even if the metal is touched. The sol coating layer such as calcium alginate used in the present invention is also excellent in this respect. That is, the anaerobic curable composition is applied to the bolt, and the member of the present invention in which the sol coating layer is formed on the bolt (pre-coated bolt) does not cause curing of the anaerobic curable composition even while touching a metal,
Stability is secured.

[0043]

Examples of the invention

Example 1 An anaerobic curable adhesive applied to a bolt has the following composition. ◎ Compound composition 90 parts of bisphenol A type methacrylate (trade name BP
E-4: Shin Nakamura Chemical Co., Ltd. Benzoyl peroxide 5 parts Thiosalicylic acid 5 parts Silica-based filler 5 parts After dipping the above composition on M10 chromate bolts, sodium alginate and gelatin mixed solution (5% sodium alginate, 2% gelatin) Dip in an aqueous solution). After that, when rapidly immersed in a mixed solution of calcium chloride and formaldehyde (5% calcium chloride, 5% formaldehyde solution), a film of calcium alginate is formed on the surface of the compound, and the anaerobic composition remains in a liquid state inside the bolt. fixed. (At this time, gelatin was also insolubilized with formaldehyde.) Even after the film was dried, the internal formulation remained in a liquid state.

After that, when tightened with a tightening torque of 300 Kgf-cm, the coating film was broken and the enclosed anaerobic curable composition flowed out, was cut off from the air to become an anaerobic state, and polymerization was started. It stuck. The breaking torque after 24 hours at room temperature was measured, and the results are shown in Table 1.

[0045]

[Table 1]

As shown in Table 1, the present composition (composition) showed no change in physical properties after tightening even after 3 months.

[0047]

Example 2 Example Using Peroxide Capsules The composition of the composition applied to the bolt was as follows. Cumene hydroperoxide 5 parts Tributylamine 5 parts Bisphenol A type metactarate (BPE-2.6: Shin-Nakamura Chemical) 80 parts Hydroxybutyl acrylate (trade name HOB: Kyoeisha Oil and Fat Chemistry) 10 parts

After dipping the above composition on an M10 chromate bolt, it is dipped in a mixed solution of sodium alginate, gelatin and gum arabic (5% sodium alginate, 2% gelatin, 1% gum arabic solution). After that, when rapidly immersed in a mixed solution of calcium salt and formaldehyde (5% calcium chloride, 5% formaldehyde solution), a film of calcium alginate was formed on the surface of the compound, and the anaerobic composition was kept in a liquid state inside. . (At this time, gelatin was also insolubilized with formaldehyde.) Even after the film was dried, the internal formulation remained in a liquid state.

After that, when it was tightened with a tightening torque of 300 Kgf-cm, the coating film was broken and the encapsulated anaerobic curable composition flowed out, and was cut off from the air to be cured in an anaerobic state, and the bolt was fixed. The breaking torque after 12 hours at room temperature was measured, and the results are shown in Table 2.

[0050]

[Table 2]

As is clear from Table 2, the present composition showed almost no change in the physical properties of tightening after 3 months.

[0052]

As described above, according to the present invention, the anaerobic curable composition layer is formed on the screwing surface of the screwing member, and this layer is coated with a water-insoluble layer, that is, a water-insoluble sol film layer. Thus, the composition layer can be prevented from flowing out, stickiness can be eliminated, and the water-insoluble sol film layer can be formed by only bringing the liquid substance into contact with a metal ion, which is extremely simple.

[Brief description of drawings]

FIG. 1 is a partial side view of a bolt used in the present invention.

FIG. 2 is a cross-sectional view showing a coated state of a liquid substance capable of forming a sol film layer.

FIG. 3 is a cross-sectional view showing a formation state of a water-insoluble sol film layer.

FIG. 4 is a partial side view of the self-locking member according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 bolt 2 screwing surface 3 composition layer 4 liquid substance 6 liquid substance containing metal ions 7 sol film layer 8 self-locking member

Claims (9)

[Claims] 1. A polymerizable compound (meta) on a screwing surface of a screwing member.
A self-locking member formed by forming an anaerobic curable composition layer comprising an allyl acid ester monomer and a peroxide polymerization initiator, and coating the composition layer with a water-insoluble layer. 2. The self-locking member according to claim 1, wherein the composition layer further comprises a polymerization accelerator. 3. The self-locking member according to claim 1, wherein the water-insoluble layer is formed by contacting a liquid substance containing a metal ion with a sol coating layer forming liquid substance capable of gelling with a metal ion. 4. The sol coating layer forming liquid substance according to claim 3,
Alkali metal alginate or ammonium salt, pectic acid alkali metal or ammonium salt, polyacrylic acid alkali metal or ammonium metal salt, carboxymethyl (or ethyl) cellulose alkali metal or ammonium salt, and silicic acid alkali metal salt. The self-locking member according to. 5. The sol coating layer-forming liquid substance according to claim 3, wherein the alkali metal alginate or ammonium salt is a composite layer of gelatin, a pectic acid alkali metal or ammonium salt is a composite layer of gelatin, and a polyacrylic acid alkali metal or ammonium is used. The self-locking member according to claim 3, which is selected from a composite layer of salt and gelatin, a composite layer of carboxymethyl (or ethyl) cellulose alkali metal or ammonium salt and gelatin, and a composite layer of alkali metal silicate and gelatin. . 6. A method of manufacturing a self-locking member comprising the following steps (a), (b) and (c). (A) a step of forming an anaerobic curable composition layer comprising a polymerizable (meth) acrylic acid ester monomer and a peroxide polymerization initiator on the screwing surface of the screw member, (b) the (a) A step of applying a sol coating layer forming liquid substance capable of gelling with metal ions on the surface of the composition layer formed by the step,
(C) A step of forming a water-insoluble sol coating layer by contacting a liquid material containing metal ions with the sol coating layer forming liquid material applied in the step (b). 7. The method for producing a self-locking member according to claim 6, wherein the composition layer further contains a polymerization accelerator. 8. The sol coating layer forming liquid substance is alkali metal alginate or ammonium salt, alkali metal pectinate or ammonium salt, polyacrylic acid alkali metal or ammonium salt, carboxymethyl (or ethyl) cellulose alkali metal or ammonium salt. 7. The method for producing a self-locking member according to claim 6, wherein the self-locking member is selected from alkali metal silicates. 9. The sol coating layer forming liquid substance is a composite layer of alkali metal alginate or ammonium salt and gelatin, a composite layer of alkali metal pectate or ammonium salt and gelatin, and a polyacrylic acid alkali metal or ammonium salt and gelatin. 7. The method for producing a self-locking member according to claim 6, which is selected from a composite layer of carboxymethyl (or ethyl) cellulose alkali metal or ammonium salt and gelatin and a composite layer of alkali metal silicate and gelatin. .