JPH11152489A - Industrial dispersion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an industrial dispersion having good disperse stability as well as good re-dispersibility in the case in which a dispersoid precipitates by using eggshell powder as a solid dispersoid. SOLUTION: This dispersion is obtained by using eggshell powder as all or a part of a solid dispersoid and using a dispersion medium as a liquid phase. An emulsion, an aqueous solution or an liquid phase is preferable as the form of the liquid phase. The objective dispersion is preferably used in order to form a functional coating film. It is preferable to use eggshell powder in which eggshell membrane is not removed or eggshell powder in which eggshell membrane remains, because the eggshell powder is excellent in disperse stability. The particle diameter of the eggshell is preferably 1-200 μm. The content of the eggshell powder in the dispersion is preferably 10-50 wt.%. A solid lubricating agent such as talc is preferable as the solid dispersoid combinedly used with the eggshell powder. The eggshell powder and the solid lubricating agent are preferably used at (40/60) to (90/10) ratio of the eggshell powder to the solid lubricating agent. Furthermore, the objective dispersion is suitable for mold-releasing agent, etc., for die casts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an industrial dispersion containing eggshell powder as a solid dispersoid. In particular, the present invention is suitable as a lubricant or a release agent applied to a portion requiring a high level of lubrication and release properties, such as between sliding surfaces between metals.
Further, the invention is an invention that can effectively utilize eggshell generated in large quantities in the food industry and contribute to environmental conservation.

Here, an industrial lubricant used for providing a lubricating function or the like between metal sliding surfaces will be mainly described as an example, but as described later, the industrial dispersion of the present invention comprises: It can be used for other various industrial applications.

[0003]

BACKGROUND ART When a lubricating coating (lubricating coating) is formed between sliding surfaces of metals, the lubricating behavior includes a fluid lubricating region where metal contact does not occur, a mixed lubrication region where metal contact starts to occur, and There are three areas of boundary lubrication areas in which friction and wear increase significantly due to metal contact (Chemical Handbook, Applied Chemistry, Fifth Edition, edited by The Chemical Society of Japan, Heisei 7-3-15) Maruzen, p. II- 131).

In the mixed / boundary lubrication region, a solid lubricant is required. As the solid lubricant, the following publication is exemplified in the publication.

[0005] Layered structural materials: molybdenum disulfide, tungsten disulfide, graphite, boron nitride, talc,
And mica.

[0006] Soft metals: gold, silver, lead, zinc, tin, indium and the like.

Polymer substances: polytetrafluoroethylene (PTFE), polyethylene, polyamide, polyimide, polycarbonate and the like.

Others: oxides (such as lead oxide and antimony oxide) and organic substances (such as melamine cyanurate and organic molybdenum).

The above-mentioned various solid lubricants are used by dispersing them in a liquid phase such as mineral oil, synthetic oil, alcohol, water and the like. The dispersion medium evaporates and evaporates after the application, and serves as a mere application carrier. Further, in addition to the role, the dispersion medium itself plays a role as a lubricating ability supplement of the solid lubricant.

When acting as a supplement for lubrication,
In addition to the above, various liquid lubricants in the form of an oil-in-water (o / w) emulsion / solution and a water-in-oil (w / o) emulsion / solution can be used.

[0011]

However, the suspension type lubricant (dispersion liquid) in which the above-mentioned solid lubricant is dispersed has not been excellent in dispersion stability. As the solid lubricant, an inorganic type lubricant is often used from the viewpoint of heat resistance, and has a higher specific gravity than the dispersion medium, and is likely to aggregate and settle.

When the inorganic solid lubricant is aggregated and settled, it is necessary to stir and re-disperse the solid lubricant before use. However, the redispersibility was not good, and as a result, the number of coating steps was increased, and it was difficult to obtain uniformity of the (lubricated) coating.

In view of the above, an object of the present invention is to provide an industrial dispersion in which a powder is a solid dispersoid, which has good dispersion stability and good redispersibility when the dispersoid sediments. The purpose of the present invention is to provide a dispersion for use.

[0014]

The industrial dispersion according to the present invention solves the above problems by the following constitution.

An industrial dispersion comprising eggshell powder as a whole or a part of a solid dispersoid, and a dispersion medium in a liquid phase.

The form of the liquid phase in the industrial dispersion of the present invention is preferably an emulsion, an aqueous solution, or an oil phase.

The industrial dispersion is desirably used for forming a functional coating.

Further, it is suitable for use as a mold release agent for die casting, a lubricant for hot forging, a lubricant for cold forging, and the like.

[0019]

[Detailed Description of Means] Next, regarding the structure of the above means,
A detailed description will be given mainly of a case where a liquid dispersion is used to form a lubricating coating between sliding surfaces between metals, that is, a case where it is used as a lubricating coating forming agent. In the following description, a composition unit is a weight unit unless otherwise specified.

(1) The industrial dispersion of the present invention is characterized in that eggshell powder is used as the whole or a part of the solid dispersoid, and the dispersion medium is in a liquid phase.

Here, eggs such as duck, quail, goose and the like can be used as raw materials of the eggshell in addition to chicken eggs.

The eggshell powder is usually prepared by drying the eggshell using a dry mill such as a vibration mill or a ball mill. However, the present invention is not limited to dry pulverization, but may be wet pulverization. In the case of wet pulverization, it can be used as it is by adding it to an aqueous solution or emulsion.

At this time, the eggshell may be substantially the eggshell membrane as used in the food industry (JP-A-57-132860, JP-A-59-4987).
No. 8, JP-A-59-71667). However, in general, it is desirable to use one in which the eggshell membrane has not been removed or in which the eggshell membrane is substantially left. This is because the remaining eggshell membrane has better dispersion stability.

Incidentally, the proportion of the eggshell (including eggshell membranes) to the total weight of the eggs is 10 to 12% by weight for chicken eggs, and the thickness of the eggshell is 0.2 to 0.4 mm. Editorial Committee, "Chemical Dictionary 9" (Showa 37-7-31)
Kyoritsu Shuppan, p. 563).

The ratio between the eggshell body and the eggshell membrane excluding the eggshell membrane is about the former / the latter = 1/20. The proteins contained in the eggshell body and eggshell membrane are 3.3% and 70.0%, respectively. Furthermore, the composition of eggshell minerals in chicken eggs is 98.48% calcium carbonate,
Magnesium carbonate is 0.84% and tribasic calcium phosphate is 0.73%. (See Taiyo Kagaku, “Eggs and Their Chemistry and Processing Techniques” (Showa 62-4-30), Korinsha, p. 58) Also, FIG.

The particle size of the eggshell powder is 0.1 to 1000 μm.
m, preferably 0.5 to 400 μm, more preferably
1 to 200 μm. If the particle size is too small, the porosity of the eggshell will decrease, and the ability to maintain dispersibility and the ability to absorb liquid lubricating components and other powdery solid lubricating components (solid dispersoids) will be included. Is undesirably reduced. On the other hand, if the particle size is too large, it is difficult to form a uniform coating film.

It is presumed that the reason why the eggshell powder exhibits good dispersibility and lubricity when used as a lubricating coating film-forming agent as described below is as follows.

Reasons for obtaining good dispersibility and redispersibility: cuticle, eggshell, and proteins contained in eggshell membranes
It is presumed to have a surfactant-like effect. That is, as described above, the eggshell of a chicken egg (including the eggshell membranes) usually contains about 95%.
It contains about 5% protein, along with% minerals. This surfactant is a polymer, surrounding other powdery dispersoids,
Disperse in a liquid phase dispersion medium.

As shown in FIG. 1, the eggshell has many pores, and the eggshell membrane also has many pores. Therefore, the eggshell has a very large surface area and adsorbs and holds other solid dispersoids. Is further improved.

Reason for obtaining the lubricating ability: The liquid lubricant component is adsorbed and held on the eggshell, which is a porous inorganic powder, and even if the temperature is high, the evaporation and thermal decomposition are not promoted, and the liquid gradually bleeds. It exhibits lubrication even in the mixed / boundary lubrication region where metal-metal contact occurs. Since the eggshell is made of an inorganic substance consisting of calcium carbonate having a hardness high enough to be used as an abrasive, it is estimated that there is little interfacial wear due to metal contact.

Incidentally, Mohs (Mohs) Katasa, which is exemplified as the above-mentioned solid lubricant, has a mica of 2.8, a talc of 1, a graphite (graphite) of 1 to 2, and a marble (Ca).
CO ₃ ) 3-4 (see Chemical Chemistry Handbook, Part II, edited by The Chemical Society of Japan, Mar., p. 475).

(2) The content of eggshell powder in the dispersion is usually
0.01-80%, preferably 0.1-75%, more preferably 10-50%.

When the content of the eggshell powder is too low, when a liquid lubricant is used in combination, the liquid lubricant cannot be sufficiently adsorbed and held, and it is difficult to impart a good lubricating ability. On the other hand, if there is too much,
The viscosity is relatively increased, adversely affecting the coating workability, and the liquid lubricant or solid lubricant is relatively reduced, so that it may be difficult to obtain a predetermined lubricating ability.

(3) As a liquid phase serving as a dispersion medium for eggshell powder,
The foregoing, namely mineral oil, synthetic oil, alcohol, water,
Furthermore, oil-in-water type (o / w type) emulsions / solutions,
Water-in-oil (w / o) emulsions / solutions can be mentioned. Furthermore, it may be composed of a grease-paste semi-fluid phase.

As the solid dispersoid used in combination with the eggshell powder, the above-mentioned solid lubricant having lubricating ability can be suitably used.

In this case, the ratio between the eggshell powder and the solid lubricant is the former / the latter = 10/90 to 90/10, preferably 40/60 to 90/10. If the amount of the eggshell powder is too small, it is difficult to ensure the dispersibility and redispersibility.

(4) The industrial dispersion of the present invention is usually applied to a metal surface to form a lubricating functional coating (lubricating coating).
The coating method can be appropriately selected according to the viscosity of the dispersion liquid, such as spray coating, dip coating, brush coating, roller coating, and flow coating.

In addition, the eggshell itself is porous, has excellent heat insulation properties, and is also excellent in heat resistance (reference: CaCO ₃
1339 ° C).

Therefore, the industrial dispersion containing the eggshell powder of the present invention can be expected to be used for forming various functional coatings as described below. Of course, depending on the application, a plurality of functions may be required.

Lubricating function coating film: lubricant for cold / hot forging, oil for drawing, release agent for green sand, drawing oil, etc.

Thermal insulation coating film: Die-cast release agent, gravity coating agent, lubricant for hot forging.

Coating film: Various paints, rust preventives.

Heat-resistant functional coating film: lubricant for cold / hot forging, anti-sintering agent.

It is needless to say that the present invention can be applied to uses other than those described above, by utilizing the above-mentioned functions and using them together with other components.

When the above-mentioned dispersion is applied to a solid surface, that is, when a functional coating film-formed body is obtained, the functional coating film to be formed is usually dried and consequently consists of eggshell powder or eggshell powder. Will be included. The functional coating film can be formed by directly applying to a solid surface in the form of an eggshell powder or a powder coating containing the eggshell powder without using a dispersion liquid. Here, the solid includes not only metal but also ceramics, wood, paper, plastics, rubber, and the like in terms of material, and the product form is arbitrary such as various molded articles and fibers.

[0046]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail based on industrial release agents and lubricants to which the present invention is applied.

A. Example of Application of Release Agent for Aluminum Die Casting (1) Preparation of Release Agent Based on the formulation shown in Table 1, an O / W type emulsion is prepared to be a liquid phase, and further, becomes a solid dispersoid in the liquid phase. Each liquid release agent was prepared by charging and dispersing the powder component.

Here, Comparative Example A-1-2 is the same as Example A-
1, a mixed powder (hereinafter referred to as "egg-shell mixed powder") prepared by approximating the inorganic composition of calcium carbonate or eggshell powder instead of eggshell powder. In Comparative Example A-3, talc belonging to the layer structure material of the solid lubricant was used in place of the eggshell powder in Example A-2 (the above-mentioned “Chemical Handbook Applied Chemistry, Fifth Edition”). Pp. II-132).

(2) Evaluation Test For each release agent, settling property / redispersibility and release property were measured according to the following methods.

Sedimentation / redispersibility test: A mayonnaise bottle (225 mL) was filled with 100 g of each release agent and left at room temperature to observe sedimentation. After settling, the mixture was shaken to visually determine redispersibility.

Releasability test: Inner diameter 50 mm, depth 30 mm after spraying each mold release agent (about 200 g / m ² )
A molten metal (aluminum alloy: ADC-12, molten metal temperature: 760 ° C.) is poured into a metal mold 12, and a 3 kg weight 14 is immediately dropped from a distance of 30 cm in height, and a load is applied. Is extruded, and the force (release force) when the aluminum casting 18 is separated from the mold 12 is measured (see FIG. 2). At this time, the mold temperature at the time of release agent application: 3
The mold temperature during pouring was 400 ° C. (3) Test results and judgment Table 2 shows the test results.

Regarding the sedimentation / redispersibility and the releasability, all of the examples are different from the corresponding comparative examples in that:
It can be seen that it has been significantly improved.

B. Application example of hot forging lubricant (1) Preparation of lubricant Based on the formulation shown in Table 3, an aqueous solution was prepared to be a liquid phase, and was used as it was (Comparative Example B-1). Example B-1 A powder component as a dispersoid was charged and dispersed.
Alternatively, a liquid lubricant of Comparative Example B-2 was prepared.

Here, Comparative Example B-1-2 is the same as Example B-
1, wherein each of the eggshell powders was replaced with the same weight of water or eggshell composition prepared powder instead of the eggshell powder.

(2) Evaluation test method: Sedimentation / redispersibility test Same as above (only for Example B-1 and Comparative Example B-2).

Lubricity Test The coefficient of friction was determined by the following ring compression test.
The mold was visually inspected for scratches after the experiment.

A mold (SKD61) of φ100 × 50 mm is heated to about 200 ° C. at the top and bottom, and each mold lubricant 1 diluted 10-fold is prepared.
5 mL was spray-coated (air pressure 4 kg / cm ² ) on the contact surface between the upper and lower mold dies.

A ring of φ30 × φ15 × 10 mm (S4
5C material) is heated to 1100 ° C. in an electric furnace.

Using a 100 t press, the rate of decrease in the height of the ring and the rate of change in the inner diameter of the ring were plotted on a theoretical curve obtained by the "Energy Method by Kudo" (usual method) to determine the friction coefficient.

(3) Test results and judgment Table 4 shows the test results.

The sedimentation and redispersibility of Example B-1 is better than that of Comparative Example B-2.

In the lubricity test, there was almost no difference in the coefficient of friction between the example and each comparative example. However, in Example B-1 of the present invention, the mold after the experiment did not show any scratches. It can be seen that the effect on the mold is small, that is, the lubricant of the example is superior in lubricating performance as compared with the comparative example.

C. Example of cold forging lubricant application (1) Preparation of lubricant An oily lubricant component having the formulation shown in Table 5 was prepared and used as a liquid phase, as it was (Comparative Example C-1), and further, a solid was added to the liquid phase. A liquid lubricant of Example C-1 or Comparative Example C-2 was prepared by charging and dispersing a powder component as a dispersoid.

Here, Comparative Example C-2 is obtained by replacing the eggshell powder with the eggshell composition prepared powder in Example C-1.

(2) Evaluation test method Settling / redispersibility test Same as above (only for Example C-1 and Comparative Example C-2).

Lubricity Test After spraying each lubricant on the inner surface of a cylindrical test piece (material: S10C, inner diameter: 15 mm) (about 200 g / m ² ), it was set in a mold, and a ball having a diameter larger than the inner diameter was set. Push a bearing ball (material: SUJ2, ball diameter: 16.67 mm) into it. As a result, the test piece undergoes a deformation in which the inner diameter increases and extends in the axial direction. By changing the combination of the inner diameter of the test piece and the diameter of the ball, the cross-sectional reduction rate is changed.

The pressing load at this time was measured using an Amsler testing machine. The difference between the initial dynamic load and the final dynamic load at the time of penetration was also measured.

(3) Test results and judgment Table 5 shows the test results.

The sedimentation and redispersibility of Example C-1 is better than that of Comparative Example C-2.

In the lubricity test, there was almost no difference in the initial load between the example and each comparative example. However, in the initial-final load difference, the example B-1 was different from the comparative examples. In addition, the ball after the test was not damaged, and it was found that the lubricant of Example was excellent in lubricity.

[0071]

Effects and Effects of the Invention The industrial dispersion of the present invention has the following effects when the eggshell powder is used as the whole or a part of the solid dispersoid and the dispersion medium is in the liquid phase.

In an industrial dispersion containing an inorganic powder as a solid dispersoid, the dispersion stability is good and the redispersibility when the dispersoid sediments is good, as supported by the above-mentioned examples. is there.

The reason is that, as described above, the protein contained in the eggshell (including the eggshell membrane) acts as a surfactant, and the eggshell itself is a porous material having a large number of pores, and the dispersion medium is a porous medium. It is presumed that, because of the penetration, the dispersion stability increases synergistically.

[0074]

[Table 1]

[0075]

[Table 2]

[0076]

[Table 3]

[0077]

[Table 4]

[0078]

[Table 5]

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a hen's egg shell

FIG. 2 is a schematic cross-sectional view showing a method for testing release properties.

[Explanation of symbols]

 12 Mold 14 Weight 16 Knockout pin 18 Aluminum casting

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI (C10M 173/02 125: 10 129: 34 145: 16 159: 02) C10N 30:04 30:08 40:24 40:36 ( 72) Inventor Takae Nagata 1-16-1, Hosoki-cho, Kasugai-shi, Aichi Pref.

Claims (9)

[Claims] 1. An industrial dispersion comprising eggshell powder as a whole or a part of a solid dispersoid, and a dispersion medium in a liquid phase. 2. The industrial dispersion according to claim 1, wherein the liquid phase is an emulsion. 3. The industrial dispersion according to claim 1, wherein the liquid phase is an aqueous solution. 4. The industrial dispersion according to claim 1, wherein the liquid phase is an oil phase. 5. The industrial dispersion according to claim 1, which is used for forming a functional coating on a solid surface. 6. The industrial dispersion according to claim 1, which is used as a release agent for die casting. 7. The industrial dispersion according to claim 1, which is used as a lubricant for hot forging. 8. The industrial dispersion according to claim 1, which is used as a lubricant for cold forging. 9. A functional coated film-formed body, characterized in that the functional coating formed on the solid surface is made of or contains eggshell powder.