Method for producing an oil gel capsule

Abstract

To develop an overlay material that is sensitive to a temperature environment and free of an aggregation phenomenon after oil discharge.SOLUTION: There are provided a production method of an oil gel capsule and a production method of a contact part for a vehicle containing an oil gel capsule. The oil gel in the oil gel capsule is sensitive to a temperature environment of the contact part for a vehicle and free of an aggregation phenomenon between gelatinizing agents (gelator) or an aggregation phenomenon between surfactant after oil discharge. The low friction characteristics and the seizure resistance characteristics of the contact part for a vehicle are improved by adding the oil gel capsule to an overlay layer without side effects caused by the aggregation phenomenon.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a material for an overlay layer formed on the surface of a vehicle contact part such as a bearing alloy.

Background Art

[0002] A bearing is one of the mechanical elements that restricts relative movement with respect to a desired movement and reduces friction between moving parts. Since a bearing is liable to suffer fatigue failure under a load by a hard roller or ball, a bearing made of an alloy substrate that is excellent in wear resistance, corrosion resistance, and thermal conductivity and has a vibration absorption function (hereinafter referred to as a bearing alloy) is mainly used.

[0003] However, bearing alloys are also inevitably subject to wear due to continuous friction, and thus the seizure resistance can rapidly deteriorate. Therefore, various coating materials, that is, overlay materials, for protecting bearing alloys from wear have been developed, and polyamideimide and lubricants are mainly used as the overlay materials.

[0004] When developing an overlay material, it is necessary to consider that the wear resistance of a bearing significantly deteriorates in the initial stage of vehicle operation. It is necessary to prevent additional wear in the initial stage of vehicle operation, that is, the initial wear stage of the bearing, and extend the life of the composite material (bearing alloy and overlay material). Therefore, it is necessary to develop an overlay material that can maintain the seizure resistance even after wear occurs in the composite material.

[0005] Patent Document 1 discloses microcapsules as one of the overlay materials. The microcapsules contain a liquid-phase lubricant inside a hard plastic skin, and when the plastic skin is physically damaged, the liquid-phase lubricant is released to the outside. It can be said that the release of the liquid-phase lubricant has no relation to the temperature environment of the composite material. Further, since the damaged plastic skin can aggregate, it not only induces engine defects but also reduces engine efficiency.

[0006] Patent Document 2 discloses a lubricant composition that is sensitive to temperature changes. Patent Document 2 relates to a method of infiltrating a lubricant composition composed of a lubricant and a gelator into the pores inside a bearing that is a sintered material. However, due to the high viscosity of the lubricant composition and the size limitation of the pores inside the bearing, its application has limitations. Furthermore, since the lubricant composition is not disclosed as an overlay material for bearings, there are limitations in referring to it as a solution for extending the life of composite materials.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0008] One object of the present invention is to develop an overlay material that is sensitive to the temperature environment. Another object of the present invention is to develop an overlay material in which no aggregation phenomenon occurs even after oil release.

Means for Solving the Problems

[0009] The present invention provides a method for manufacturing oil gel capsules. The present invention includes (a) a step of mixing an oil and a gelator to produce an oil gel, and (b) a step of mixing the oil gel and an aqueous solution of a surfactant to generate at least one or more oil gel capsules.

[0010] Preferably, the oil gel capsules are formed by the surfactant surrounding the oil gel.

[0011] Preferably, the oil gel in the step (b) is in a liquid state.

[0012] Preferably, the oil gel capsule has a size of 0.1 or more and less than 10 μm.

[0013] Preferably, the oil gel capsule has a size of 0.1 or more and 1 μm or less.

[0014] Preferably, the oil and the gelator are mixed using an ultrasonic crusher.

[0015] Preferably, the aqueous solution of the oil gel and the surfactant is mixed using an ultrasonic crusher.

[0016] Preferably, the present invention further includes a step (c) of drying the aqueous solution. Preferably, the aqueous solution in (c) is freeze-dried.

[0017] Preferably, after the step (c) is carried out, the oil gel capsules are recovered as oil powder in which at least two or more oil gel capsules are aggregated.

[0018] In addition, the present invention provides a method for manufacturing a vehicle contact part including the oil gel capsule. The present invention includes the above-mentioned steps (a) to (c), and further includes a step (d) of redispersing the oil powder in an organic solvent to produce a first organic solution containing 2 to 10 wt% of the oil gel capsule, a step (e) of mixing the first organic solution and a second organic solution containing 30 to 50 wt% of polyamideimide and an additive in a weight ratio of 1:0.5 to 1:2 to produce an overlay mixed solution, and a step (f) of coating the overlay mixed solution on the surface of the vehicle contact part and then drying the vehicle contact part.

[0019] Preferably, the overlay layer formed through the step (f) has a thickness of 10 to 30 μm. [Advantages of the Invention]

[0020] According to the present invention, it is possible to provide an overlay material that is sensitive to the temperature environment and improves friction resistance and seizure resistance characteristics. According to the present invention, neither the aggregation phenomenon of the gelator nor the aggregation phenomenon of the surfactant occurs even after oil is released. [Brief Description of the Drawings]

[0021]

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Mode for Carrying Out the Invention

[0022] The present invention will be described in detail below. However, the present invention is not limited or restricted by exemplary embodiments. The objects and effects of the present invention will be naturally understood or further clarified by the following description, and the objects and effects of the present invention are not limited only by the following description. Also, in describing the present invention, when it is determined that a specific description of known technology related to the present invention may muddy the gist of the present invention, the detailed description thereof will be omitted.

[0023] FIG. 1 shows a bearing including the oil gel capsules of the present invention. FIGS. 2(a) to (c) are confocal fluorescence images of the oil gel capsules contained in the bearing. Referring to FIGS. 1 and 2, the bearing 10 can include a back steel 100, a bearing alloy 200, and an overlay layer 300, and the overlay layer 300 can include at least one or more oil gel capsules 310.

[0024] The oil gel capsule 310 means a particle including an oil gel 311 and a surfactant 312 surrounding the oil gel 311, and more specifically, a particle including an oil gel 311 and at least one or more surfactants 312 bonded to the oil gel 311. The oil gel 311 refers to an oil containing a gelator 311B, and can include an oil 311A and a gelator 311B.

[0025] FIG. 3 shows a method for manufacturing an oil gel capsule. Referring to FIG. 3, the method for manufacturing an oil gel capsule can include: (a) mixing an oil and a gelator to form an oil gel; and (b) mixing the oil gel and an aqueous surfactant solution to generate at least one or more oil gel capsules. Hereinafter, with further reference to FIGS. 4 to 11, steps (a) and (b) will be described in detail.

[0026] (a) Step: Mix the oil and the gelator to form an oil gel. Add the gelator to the oil. However, since it is not necessary to specify the addition target and the addition direction, the oil may be added to the gelator. The oil and the gelator can be mixed using an ultrasonic crusher for more uniform mixing. The formed oil gel is in a gel state.

[0027] The weight ratio of the gelator (the weight of the gelator relative to the total weight of the oil) during the mixing of the oil and the gelator is preferably a weight ratio effective for gelling the entire oil to be mixed. Also, since the phase transition temperature of the oil gel changes according to the weight ratio of the gelator, the weight ratio of the gelator is preferably a weight ratio effective for the oil gel to maintain a gel state at room temperature, and is preferably a weight ratio effective for maintaining a gel state in all temperature environments (up to about 60 °C) that the bearing containing the oil gel passes through before being attached to the vehicle.

[0028] The phase transition temperature of the oil gel refers to the temperature at which the gelled oil gel liquefies into a liquid state, or the liquid oil gel gels into a gelled oil gel. The oil gel maintains a gel state at a temperature below the phase transition temperature and maintains a liquid state at a temperature above the phase transition temperature.

[0029] According to an embodiment of the present invention, the oil may be engine oil, and the gelator may be 12-Hydroxyoctadecanoic acid (hereinafter, 12-HSA). The weight ratio of 12-HSA is preferably 1 to 10 wt% based on the total weight of the engine oil, and the oil gel can have a phase transition temperature of about 60 °C or more and about 70 °C or less. When less than 1 wt% of 12-HSA is mixed with the engine oil, the network fiber structure of 12-HSA is not formed in the engine oil, and thus no oil gel is formed. When more than 10 wt% of 12-HSA is mixed with the engine oil, it reaches a saturated state where the increase in the phase transition temperature of the oil gel decreases according to the increase in the 12-HSA weight ratio, and the weight of the engine oil relative to the weight of the gelator becomes relatively small, so the lubricating properties of the oil gel or the oil gel capsule decrease. Therefore, 12-HSA is preferably added in an amount of 1 to 10 wt% based on the total weight of the engine oil. However, the type of the gelator and the weight ratio of the gelator are not limited thereto.

[0030] Figures 4(a) and 4(b) show the results of measuring the phase transition temperature of the oil gel according to the weight ratio of 12-HSA by DSC. Referring to Figures 4(a) and 4(b), it can be confirmed that an oil gel having a phase transition temperature exceeding about 61 °C can be formed when 1.5 wt% or more of 12-HSA is added.

[0031] Figure 5 is a photograph taken at 25°C after mixing engine oil and 2 wt% of 12-HSA to form an oil gel having a phase transition temperature of about 62°C. Figure 5(a) is an oil gel without added dye, and Figure 5(b) is an oil gel with added dye. The dye was added to more clearly show the state of the oil gel. Referring to Figure 5(a) and Figure 5(b), it can be seen that the oil gel exists in a non-fluid gel state in a temperature environment lower than the phase transition temperature of about 62°C. The lack of fluidity can be seen from the fact that the surface of the oil gel is not parallel to the ground plane. More specifically, the gel state of the oil gel refers to a state in which the oil is confined and held in the network fiber structure of the gelator.

[0032] Figures 6(a) and 6(b) are photographs taken after heating the oil gels of Figures 5(a) and 5(b) at 90°C. Referring to Figures 6(a) and 6(b), it can be seen that the oil gels exist in a liquid state with restored fluidity in a temperature environment higher than the phase transition temperature of about 62°C. The presence of fluidity can be seen from the fact that the surface of the oil gel is approximately parallel to the ground plane. More specifically, the liquid state of the oil gel refers to a state in which the network fiber structure of the gelator is disassembled and the gelator is dispersed in the oil.

[0033] Comparing Figures 6(a) and 6(b) with Figures 5(a) and 5(b), it can be seen that the oil gel in the liquid state is more transparent than the oil gel in the gel state. When the oil gels of Figures 6(a) and 6(b) are cooled to 25°C, they can return to the state of the oil gels of Figures 5(a) and 5(b).

[0034] (b) Step: Mix the oil gel and the aqueous surfactant solution to produce at least one or more oil gel capsules. The oil gel capsules are formed by surrounding the oil gel with a plurality of surfactant molecules in the aqueous surfactant solution. On the one hand, it can be regarded that the oil gel is encapsulated by the surfactant. More specifically, since the oil gel is lipophilic (hydrophobic) and the aqueous surfactant solution is hydrophilic, an interface is formed between the surface of the oil gel and the aqueous solution, and the lipophilic part of the surfactant faces the oil gel while the hydrophilic part of the surfactant faces the aqueous solution, and the oil gel capsules are formed.

[0035] Preferably, an oil gel in a liquid state can be mixed with the aqueous surfactant solution to produce oil gel capsules. The gel-state oil gel can be liquefied in advance and mixed with the aqueous surfactant solution. After adding the gel-state oil gel to the aqueous surfactant solution or after adding the aqueous surfactant solution to the gel-state oil gel, while mixing with an ultrasonic crusher, the gel-state oil gel can be liquefied using the thermal energy coming out of the ultrasonic crusher. In any case, it is preferable to use an ultrasonic crusher for more uniform mixing.

[0036] The surfactant can refine the oil gel, so that refined oil gel capsules can be produced. By refining the oil gel, the oil gel capsules can be uniformly dispersed by the overlay layer. The oil gel capsules are formed to be smaller than 10 μm, which is the average thickness of the overlay layer, and their size is 0.1 or more and less than 10 μm. Preferably, the size of the oil gel capsules is 1 to 5 μm, and more preferably, 1 μm or less.

[0037] The surfactant can prevent the aggregation between the refined oil gels when the aggregated oil gel capsules, which are defined as oil powder below, are redispersed in the organic solvent.

[0038] According to an embodiment of the present invention, the surfactant may be PVA (Polyvinyl alcohol), and an aqueous PVA solution of 1 to 10 wt% can be mixed with the oil gel. Here, 1 to 10 wt% refers to the ratio of the weight of PVA to the weight of the aqueous PVA solution. When an aqueous PVA solution of less than 1 wt% is mixed with the oil gel, when the aggregated oil gel capsules, which are defined as oil powder below, are redispersed in the organic solvent, the aggregation phenomenon between the oil gel capsules occurs strongly and the aggregated oil gel capsules are not redispersed. When an aqueous PVA solution of more than 10 wt% is mixed with the oil gel, the content of the oil in the oil gel capsule relatively decreases, and the lubricating properties of the oil gel or the oil gel capsule decrease. Since the role of the surfactant is in the refinement of the oil gel, the uniform dispersion in the overlay layer of the oil gel capsule, and the prevention of aggregation between the oil gels, the type of the surfactant and the content of the surfactant are not limited to this, and can be selected from anionic surfactants, cationic surfactants, amphoteric surfactants or nonionic surfactants. On the other hand, the weight ratio at the time of mixing the oil gel and the aqueous surfactant solution is 1:2 to 1:10.

[0039] Figures 7(a) and 7(b) are photographs taken after adding and mixing a 2 wt% aqueous PVA solution to the oil gel of Figures 6(a) and 6(b). Referring to Figures 7(a) and 7(b), it can be confirmed that the oil gel, which was transparent in the liquid state before mixing, has changed to white like milk. This means that an emulsion of fine particles in the aqueous solution has been generated, and the fine particles refer to oil gel capsules.

[0040] Figures 8 to 10 are confocal fluorescence images of the oil gel capsules in the aqueous solution of Fig. 7(b). Fig. 11 shows a size distribution graph of the oil gel capsules in the aqueous solution of Fig. 7(a) measured by Dynamic Light Scattering. Referring to Figs. 8 to 11, it can be confirmed that the oil gel capsules may not have a spherical shape and their size is 1 μm or less. A more specific size of the oil gel capsules is 0.1 μm (= 100 nm) to 1 μm (= 1000 nm).

[0041] The method for manufacturing the oil gel capsules may further include the step of drying an aqueous solution containing (c) at least one or more oil gel capsules. By drying the aqueous solution containing the oil gel capsules, the distance between the oil gel capsules is reduced, and the oil gel capsules may aggregate. The aggregation of the oil gel capsules does not mean that at least two or more oil gel capsules are combined into one oil gel capsule, but means a state where the surfactants of each oil gel capsule are physically in contact with each other. The aggregated oil gel capsules are viscous like clay, have a powder form, and have a soft touch like powder. Hereinafter, an aggregate of at least two or more oil gel capsules is referred to as an oil powder. The oil powder can be added to an organic solvent, and the aggregated oil gel capsules can be redispersed. The drying in step (c) is preferably carried out using a freeze dryer.

[0042] Figs. 12(a) and 12(b) are photographs taken after freeze-drying the aqueous solutions of Figs. 7(a) and 7(b). Referring to Figs. 12(a) and 12(b), the oil powder can be confirmed, and it can be said that the oil gel capsules are recovered in a powder form. One powder on Figs. 12(a) and 12(b) has a size distinguishable by the naked eye, but since the oil gel capsules generated through step (b) have a size in the micro unit or sub-micro unit, it can be said that one powder is formed by the aggregation of a plurality of oil gel capsules.

[0043] Hereinafter, the process of adding the oil gel capsules manufactured through steps (a) to (c) to the overlay layer of the bearing will be described in detail. Each step described below is referred to as step (d), step (e), and step (f). (d) Step: Add the oil powder to the organic solvent to redisperse the aggregated oil gel capsules. The aggregated oil gel capsules can be dispersed as shown in FIGS. 8 to 10. However, unlike FIGS. 8 to 10, since the oil gel and the organic solvent, for example, NMP (N-Methyl-2-pyrrolidone), are also lipophilic, no interface is formed on the surface of the oil gel, and a part of the surfactant bound to the oil gel can be dispersed in the organic solvent. An organic solution containing 2 to 10 wt% of the oil powder is referred to as the first organic solution, and the first organic solution can be said to be an organic solution containing 2 to 10 wt% of the oil gel capsules. Here, wt% means the ratio of the weight of the oil gel capsules to the total weight of the first organic solution.

[0044] FIGS. 13(a) and 13(b) are photographs taken after redispersing the oil powder in FIGS. 12(a) and 12(b) in the organic solvent NMP to produce a first organic solution containing 10 wt% of the oil gel capsules. Referring to FIGS. 13(a) and 13(b), it can be seen from the translucent color of the first organic solution that the aggregation between the oil gel capsules has been eliminated.

[0045] (e) Step: The first organic solution and the second organic solution containing 30 to 50 wt% of polyamideimide and an additive can be mixed at a weight ratio of 1:0.5 to 1:2 to produce an overlay mixed solution. Here, wt% means the weight ratio of the solid content to the total weight of the second organic solution. The solvent of the second organic solution may be NMP. FIGS. 14(a) and 14(b) are photographs taken after mixing the first organic solution in FIGS. 13(a) and 13(b) and the second organic solution containing 50 wt% of polyamideimide and an additive at a weight ratio of 1:1.

[0046] (f) Step: After coating the overlay mixed solution on the surface of the bearing alloy, the bearing can be dried. FIGS. 15(a) and 15(b) are photographs taken after coating the overlay mixed solution of FIGS. 14(a) and 14(b) on the surface of the bearing alloy. The drying of the bearing may be carried out in one step, or may be carried out in two steps for the preservation of the oil gel capsules. The dried bearing can have an overlay layer with a thickness of 10 to 30 μm.

[0047] Hereinafter, examples and comparative examples of the present invention will be described. Manufacturing process of oil gel capsules After adding 0.3030 g (about 2 wt%) of the gelator 12-HSA to 15 g of engine oil and mixing using an ultrasonic crusher, an oil gel having a phase transition temperature of about 62 °C was produced. 5 g of the oil gel was liquefied, 75 ml of a 2 wt% PVA aqueous solution was added, and then mixed using an ultrasonic crusher to produce oil gel capsules. The aqueous solution containing the oil gel capsules was freeze-dried using a freeze dryer to remove water, and the oil powder was recovered.

[0048] Manufacturing process of the overlay layer Example 1 10 g of oil powder was added to 90 g of NMP solvent to produce an NMP solution (the first organic solution) containing 10 wt% of oil gel capsules. During the production of the first organic solution, the oil gel capsules were uniformly redispersed in the NMP solvent using a stirrer. After preparing an NMP solution (the second organic solution) containing 50 wt% of polyamide-imide and additives (including lubricants), 50 g of the first organic solution and 50 g of the second organic solution were mixed to produce an overlay mixed solution. The overlay mixed solution was coated on the surface of the bearing alloy, dried at 150 to 200 °C for 30 minutes, and then dried at 210 to 240 °C for 15 minutes to produce an overlay layer with a thickness of about 10 μm (Example 1 is represented by Sample 1 in FIGS. 16 and 17).

[0049] Example 2 The overlay mixed solution of Example 1 was coated twice to produce a coating layer with a thickness of about 20 μm (Example 2 is represented as Sample 2 in FIGS. 16 and 17).

[0050] Example 3 The overlay mixed solution of Example 1 was coated three times to produce a coating layer with a thickness of about 30 μm (Example 3 is represented as Sample 3 in FIGS. 16 and 17).

[0051] Comparative Example 1 A trial product DLA02 without oil gel capsules was used to produce an overlay layer of about 10 μm (Comparative Example 1 is represented as DLA02 in FIGS. 16 and 17).

[0052] FIGS. 16 and 17 show the results of the reciprocating friction test of the steel disk specimens of Examples 1 to 3 and Comparative Example 1. The test conditions were Dry condition, 10 minutes, a load of 50 N, a reciprocating speed of 5 Hz, and a reciprocating distance of 10 mm stroke. Referring to FIGS. 16 and 17, in the case of Comparative Example 1 without oil gel capsules, a continuous increase in the friction coefficient and a decrease in the contact voltage were observed through repeated friction tests. However, in the case of Examples 1 to 3, it can be seen that the initial friction coefficient and contact voltage were maintained even after 10 minutes. That is, it can be confirmed that the oil gel capsules improved the low friction characteristics and seizure resistance characteristics of the bearing.

[0053] Figures 18(a) to 18(c) show the operation process of the oil gel capsule. At the initial stage of vehicle operation, the friction towards the bearing causes wear or cracks along with a local temperature rise in the overlay layer and the bearing alloy. The local temperature rise can transfer the oil gel in the gel state to the oil gel in the liquid state, and the oil gel in the liquid state can form a lubricating film at the worn or cracked site. Thereby, additional friction and wear on the bearing can be suppressed at the wear stage in the initial stage of vehicle operation, and the life of the bearing can be extended. Also, since the gelator is diluted by the excessive engine oil and the gelator does not form a network fiber structure at a low concentration, no aggregation phenomenon of the gelator occurs after the oil is released. Also, the surfactant is diluted by the engine oil and no aggregation phenomenon occurs.

[0054] The oil gel capsule is added to the lubricant, and the lubricating characteristics of the lubricant can be further improved. Furthermore, with the emerging need for developing next-generation environmentally friendly vehicles, such as highly efficient engines, it can also be applied to engines for hybrid vehicles where the engine friction and wear environment become even more severe, electric vehicles operating in a lubricant-free environment, and hydrogen fuel cell vehicles.

[0055] Although the present invention has been described in detail through typical embodiments above, those with ordinary knowledge in the technical field to which the present invention pertains will be able to understand that various modifications can be made to the above-described embodiments without departing from the scope of the present invention. Therefore, the scope of the rights of the present invention should not be defined by being limited to the described embodiments, but should be defined not only by the scope of the following claims but also by all changes or modified forms derived from the scope of the claims and the equivalent concept.

Explanation of Reference Numerals

[0056] 10 ··· Bearing 100 ··· Back Steel 200 ··· Bearing Alloy 300 ··· Overlay layer 310 ··· Oil gel capsule 311 ··· Oil gel 311A ··· Oil 311B ··· Gelator 312 ··· Surfactant

Claims

1. (a) mixing an oil and a gelling agent to produce an oil gel; and (b) mixing the oil gel and an aqueous solution of a surfactant to produce at least one oil gel capsule, wherein the oil is engine oil, the gelling agent is 12-hydroxyoctadecanoic acid, and in step (a), the weight ratio of the 12-hydroxyoctadecanoic acid mixed with the engine oil is 1 to 10 wt% based on the total weight of the engine oil; the oil gel has a phase transition temperature of 60°C or higher and 70°C or lower; the oil gel retains a gel state at a temperature below the phase transition temperature and a liquid state at a temperature above the phase transition temperature; the weight ratio of the gelling agent is an effective weight ratio for the oil gel to retain a gel state in all temperature environments until the bearing containing the oil gel is mounted on a vehicle, a method for manufacturing an oil gel capsule, characterized by this.

2. The method for manufacturing an oil gel capsule according to claim 1, wherein the oil gel capsule is produced by the surfactant surrounding the oil gel.

3. The method for manufacturing an oil gel capsule according to claim 1, wherein the oil gel in step (b) is in a liquid state.

4. The method for manufacturing an oil gel capsule according to claim 1, wherein the oil gel capsule has a size of 0.1 or more and less than 10 μm.

5. The method for manufacturing an oil gel capsule according to claim 1, wherein the oil gel capsule has a size of 0.1 or more and 1 μm or less.

6. In step (a), the oil and the gelling agent are mixed using an ultrasonic crusher, a method for manufacturing an oil gel capsule according to claim 1, characterized by this.

7. In step (b), the oil gel and the aqueous solution of the surfactant are mixed using an ultrasonic crusher, a method for manufacturing an oil gel capsule according to claim 1, characterized by this.

8. The method for manufacturing an oil gel capsule according to claim 1, wherein the surfactant is PVA (Polyvinyl alcohol).

9. In the step (b), the oil gel is mixed with an aqueous solution of 1 to 10 wt% of the surfactant, and the method for producing an oil gel capsule according to claim 8, characterized in that.

10. (c) The method for producing an oil gel capsule according to claim 1, further comprising the step of drying the aqueous solution.

11. In the step (c), the aqueous solution is freeze-dried, and the method for producing an oil gel capsule according to claim 10, characterized in that.

12. After the implementation of the step (c), the oil gel capsule is recovered as an oil powder in which at least two or more oil gel capsules are aggregated, and the method for producing an oil gel capsule according to claim 10, characterized in that.

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