JPH0534594Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention is a cosmetic pencil used for eyebrows, eye shadows, lipsticks, etc., especially a cosmetic pencil in which a cosmetic core material is covered with a resin case. This is related to the improvement of.

《Prior art and its problems》 Cosmetic pencils that have been commercially available have generally had a core material covered with a wooden case, but the manufacturing process was complicated and time-consuming. However, due to the recent rise in the price of wood, it has become difficult to obtain high-quality wood at a low price, which has led to the development of pencils that use a synthetic resin case as a covering or reinforcing material.

Of course, the case for this type of cosmetic pencil requires a certain degree of strength to prevent the core material from breaking, but at the same time, it also needs to have excellent cutting properties when cutting out the core material. required. Therefore, although it has been proposed to make the coating material porous by adding a foaming agent to the synthetic resin, it is necessary to make the coating material porous throughout the wall thickness in order to obtain sufficient machinability. Problems have been pointed out, such as not only deteriorating the appearance but also the fact that the dimensional accuracy cannot be improved much because the molding method is limited to extrusion molding.

Here, as disclosed in Japanese Utility Model Publication No. 60-25944, the base resin is a material made of a mixture of soft polyethylene and polyethylene wax, and the core material is a mixture made by blending an inorganic filler with this base resin. A coated cosmetic pencil has been proposed. In this proposal, polyethylene wax, which has a chemical affinity with polyethylene and mixes well with it, is added to polyethylene, which is inexpensive but has poor machinability when used alone, in order to improve its machinability. ing. Furthermore, an inorganic filler such as calcium carbonate is added to this mixture in order to improve the hardness, dimensional stability, and moldability of the case. However, the inorganic filler adopted in this proposal is
The efficiency of the hardness improvement effect with respect to the amount added is not necessarily good, and it is necessary to add a considerable amount of inorganic filler to ensure sufficient hardness of the case, which causes problems such as increasing the weight of the pencil. It was hot.

On the other hand, as disclosed in Japanese Utility Model Publication No. 60-5858, a cosmetic pencil whose core material is coated with a mixture of polyethylene and fine crystalline cellulose powder has been developed. This product is sufficient in terms of strength and appearance, and the crystalline cellulose fine powder contributes to improving hardness to a greater degree than inorganic fillers such as calcium carbonate, so the amount of compounding is relatively small, so it is easy to use during molding. Although the properties are not bad, unless the amount of crystalline cellulose fine powder blended is at least about 25% by weight based on the polyethylene, there tends to be some difficulty in machinability. Furthermore, since crystalline cellulose is quite expensive as a filler, there is a problem in that it increases the cost of pencils that are used in large quantities. Furthermore, since crystalline cellulose fine powder has the property of being difficult to disperse in polyethylene, it is difficult to disperse it at the desired mixing ratio throughout the pencil, making it difficult to obtain uniform cutting properties throughout the pencil. However, simply increasing the amount of fine powder blended would cause the hardness of the entire pencil to increase too much, resulting in poor machinability.

Here, the present inventor has discovered that when mixing crystalline cellulose fine powder with polyethylene, the above-mentioned polyethylene wax not only exhibits the function of improving machinability, but also that the crystalline cellulose fine powder is completely mixed into polyethylene. By adding this polyethylene wax, it was possible to improve the dispersibility of microcrystalline cellulose powder in polyethylene and obtain uniform cutting performance throughout the pencil. It has been found that it is possible to reduce the blending ratio of the crystalline cellulose fine powder, thereby achieving both appropriate hardness and cost reduction.

<<Purpose of the invention>> The present invention relates to the improvement of the conventional cosmetic pencil mentioned above, and its purpose is to create a cosmetic pencil that can be manufactured at low cost and has uniform and comfortable cutting properties over the entire pencil. It is about providing.

《Means for solving the problems》 In order to achieve the above-mentioned purpose, the cosmetic pencil according to the present invention uses polyethylene 30~30 as the base material.
90% by weight, 5 to 30% by weight of crystalline cellulose fine powder mixed into the base material to increase hardness, and polyethylene wax as a dispersant to increase the dispersibility of the crystalline cellulose fine powder in the base material. The present invention is characterized in that a mixture mainly containing 5 to 40% by weight of Tux is formed into an elongated hollow body, and a cosmetic core material is press-fitted and solidified into the hollow body.

<<Effect>> By adding polyethylene wax as a dispersant that functions to disperse the crystalline cellulose fine powder in polyethylene, the dispersibility of the crystalline cellulose fine powder in polyethylene is significantly improved, resulting in uniform distribution over the entire pencil. Not only can machinability be obtained, but the blending amount of the crystalline cellulose fine powder is appropriate, and a cost reduction can be achieved while ensuring good hardness.

《Example》 The figure shows a cosmetic pencil according to an example of the present invention. After being formed by molding, a core material in a molten or softened state is press-fitted and filled into the core material, and the core material is then solidified. The hollow body 3 is mainly made of polyethylene, crystalline cellulose fine powder, and polyethylene wax, and is formed of a material in which a small amount of pigment or the like is mixed as necessary.
Low-density polyethylene is preferred, and crystalline cellulose fine powder is added to it to improve hardness and machinability, but as mentioned above, when these two components are used alone, the ratio of crystalline cellulose fine powder is compared. Not only does this increase the material cost due to the need for a high target density, but it is also difficult to disperse the crystalline cellulose fine powder uniformly in polyethylene, so in this invention we decided to further mix polyethylene wax as a dispersant. be. Since this polyethylene wax is an ethylene-based resin that has chemical affinity with the base material polyethylene, the two mix extremely well, resulting in improved machinability compared to polyethylene alone, resulting in a ratio of crystalline cellulose fine powder. Even if the material is small, if it is hard and difficult to cut, or if the cutting debris becomes crumbly, it will not last forever. Also, according to experiments conducted by the present inventor,
When mixed with polyethylene wax, the dispersibility of microcrystalline cellulose powder in polyethylene was significantly improved, and even when the blending amount was increased to 30% by weight, it was confirmed that it was evenly dispersed and uniform cutting performance was obtained throughout the pencil. It was done.

In the hollow body 3 consisting of the above three components, it is necessary to mix 30 to 90% by weight of polyethylene, 5 to 30% by weight of fine crystalline cellulose powder, and 5 to 40% by weight of polyethylene wax as a dispersant. It is. If the amount of polyethylene is less than the above range, its function as a base material will be reduced and it will become hard and difficult to cut, while if it is too much, it will be difficult to obtain the desired hardness. In addition, when the crystalline cellulose fine powder is within the above range, machinability, hardness, dimensional stability, and moldability are good, but when it is less than the above range, the comfort during cutting, especially the crispy feel, tends to be lost. On the other hand, if the amount is increased, the weight of the pencil will increase unnecessarily and the cost will increase, while no noticeable improvement in properties will be observed.
Furthermore, when polyethylene wax is within the above range, when sharpened with a manual pencil sharpener, the cutting scum will not fall apart and will remain continuous, but if it exceeds the above range, the cutting scum will become small pieces and become tattered. If the amount is less than the above range, the dispersibility of the crystalline cellulose fine powder will be poor, and the resistance during cutting will increase, so the purpose of mixing polyethylene wax will be lost. .

Next, a preferred embodiment of the cosmetic pencil according to the present invention will be shown.

51% by weight of low density polyethylene with a molecular weight of approximately 20,000 and 34% by weight of polyethylene wax with a molecular weight of approximately 2,000.
Weight% and crystalline cellulose fine powder (Asahi Kasei:
A hollow body 3 was formed by injection molding using a material obtained by mixing 15% by weight of Avicel PH101), and a core material 2 was filled in the hollow body 3 to obtain a cosmetic pencil 1. This product had a good appearance and sufficient strength to protect the core material 2, and also provided a comfortable cutting feeling and continuous shavings.

<<Effects of the invention>> As mentioned above, the cosmetic pencil according to the present invention not only exhibits the function of improving machinability when mixing the crystalline cellulose fine powder with polyethylene, but also exhibits the function of improving the machinability when mixing the crystalline cellulose fine powder with the polyethylene. By adding polyethylene wax as a dispersant that functions to uniformly disperse the entire pencil, it is possible to improve the dispersibility of the crystalline cellulose fine powder in polyethylene, resulting in uniform cutting properties throughout the pencil. At the same time, it is possible to reduce the blending ratio of the crystalline cellulose fine powder, thereby ensuring both appropriate hardness and cost reduction.

[Brief explanation of the drawing]

The figure is a partially cutaway perspective view showing a cosmetic pencil according to an embodiment of the present invention. 2...Cosmetic core material, 3...Hollow body.

Claims (1)

[Scope of utility model registration request] 30 to 90% by weight of polyethylene as a base material, 5 to 30% by weight of crystalline cellulose fine powder mixed into the base material to increase hardness, and to increase the dispersibility of the crystalline cellulose fine powder in the base material. 5 to 40% by weight of polyethylene wax as a dispersant is formed into an elongated hollow body, and a cosmetic core material is press-fitted and solidified into the hollow body. pencil.