GB2224368A - A container for cosmetics - Google Patents

Abstract

A container for cosmetics comprises a substrate 2 and layer 3 having a cavity of a predetermined pattern for packing a cosmetic, prepared by adhering a photosensitive resin 3 to the substrate, exposing the resin to light through a mask, and washing the resin to remove an unexposed area to form the cavity. The container can have a greater depth if a separate developed photosensitive layer having a through-hole cavity having the same pattern is adhered to the layer 3 (Fig 3 not shown). Alternatively, a moulded substrate with protrusions can be formed, a photo-sensitive resin adhered thereto, which is then image exposed and developed to produce a pattern on the protrusions and thus produce a deeper container (Fig 6. not shown). <IMAGE>

Description

"A Container for Cosmetics' In general, cosmetics are sold in a state packed in, for example, a dish-shaped container having a cavity for packing a cosmetic such as rouge, or in recent years a card-shaped container produced by forming a shallow recess on a thin sheet to pack a cosmetic therein.

Since they are produced and sold in large quantities regardless of whether the shape of the container itself or the cavity for packing a cosmetic is simple or complicated and are not products of individual production, an important factor in the production technology is how to mass-produce them efficiently.

Examples of the conventional process for producing the above-described containers for cosmetics include the following: (1) A trimming die conforming to the shape of a packed cosmetic is prepared, and a thick material is punched to this shape. When a base is necessary, a base sheet is adhered thereto by means of an adhesive, thermal fusing, etc.

(2) When plastics material is employed, a mould for press embossing is prepared and a sheet material is press-moulded therewith.

(3) A mould is prepared, and cast moulding is conducted.

(4) When plastics material is employed, a mould for injection moulding or vacuum moulding is prepared, and the material is moulded therein.

In order to meet recent consumer demands, there is a need to invidividualize and differentiate the goods. It is desirable also in the field of cosmetics to provide a variety of goods which are different from each other in pattern and coloration even when their applications and functions are the same. In order to meet this demand, it is necessary to develop a process which enables the goods to be efficiently produced in a plurality of kinds in small lots.

For example, a process wherein a thin sheet is skived is considered as a technique for producing individual containers. However, even in the case of a small-lot production, when they must be produced in amounts requiring mass-production on a commercial scale, a technology suitable for the products of individual production is not unfavourable in the production of the containers for cosmetics from the viewpoint of cost.

Under these circumstances, the present inventors have made extensive and intensive studies with a view to developing, for example, a container provided with cavities for packing various kinds of cosmetics therein and suitable for small-lot production and a process for producing the same, which have led to the present invention.

When cosmetic goods are provided by packing a dishshaped container made of metal, such as stainless steel or aluminium, or a plastics material with, for example, a make-up cosmetics among general cosmetics through pressing or casting, the container is usually a circular, rectangular, or triangular dish. As described above, it is very desirable also with respect to cosmetics which have come to be one of the fashionable goods in recent years to provide these containers efficiently at low cost as a container provided with cavities having arbitrary figures and patterns.

Accordingly, the present inventors have made a study on a material for a container which enables intended figures and patterns to be arbitrarily and easily formed in a recess for packing a cosmetic, and a process for producing the container, and further contemplated the utilization of a technique for producing a printed circuit board or a technique for preparing a flexographic printing plate which items are utterly different from those for the present invention in the application and field.Although these techniques are not those for producing a container for packing a liquid or a solid, a process comprising exposing a photoresist to light through a mask having a desired positive or negative image of a fine pattern, developing the image, washing and removing an uncured area and, if necessary, conducting etching to form unevennesses on the sheet is common in a broad sense to the production of the container and the preparation of the above-described printed circuit board and flexographic printing plate, and is suitable for preparation of a fine pattern.

The present inventors have further conducted studies with a view to applying the above-described technique to the production of a container, which have led to the completion of the present invention.

It is an object of the present invention to enable a plurality of kinds of containers to be produced in small lots and, at the same time, to provide a container for cosmetics which requires less cost for the preparation of a mould.

Accordingly this invention provides a container for cosmetics composed of a sheet-shaped substrate and an engraved layer having a cavity of a predetermined pattern for packing a cosmetic, prepared by adhering a material comprising a photosensitive resin to said substrate exposing said resin to light through a mask, and washing said resin to remove an unexposed area to form the cavity.

From a further aspect the invention provides a method of forming a cosmetics container wherein a photo sensitive resin layer is laid down in a sheet-like substrate, a mask defining a predefined pattern is laid over the resin layer which is then exposed to light to etch the desired pattern into the resin layer, the resin is washed to remove unexposed areas of the resin layer to form cavities in said predetermined pattern, and the cavities are filled with cosmetic materials.

The present invention enables a container to be formed, which can be rapidly produced in a form having a complicated figure with high accuracy, is chemically and physically stable as a container for cosmetics and meets the requirements regarding sufficient chemical resistance, heat resistance, surface hardness, etc., and enables the protection and decoration of the surface thereof.

The present invention further provides for the production of a container for cosmetics which enables not only an area for packing a cosmetic but also a depth of the recess to be arbitrarily selected.

The invention may be performed in various ways and preferred embodiments thereof will now be described with reference to the accompanying drawings, in which: Figure 1 is a schematic perspective view of an example of a structure of a container for cosmetics according to the present invention; Figure 2 is an explanatory view of the state of the preparation of an engraved layer; Figure 3 is a schematic side view of the preparation of an example of a container comprising laminated engraved layers; Figure 4 is a schematic view of vacuum moulding of a pre-moulded container comprising a flat substrate and, formed thereon, an engraved layer to form cavities on the substrate; and Figure 5 and 6 are each an explanatory view of a method of forming a container comprising previously forming unevennesses on a substrate and forming an engraved layer on said uneven substrate, Figure 5 illustrating the press moulding of the substrate and Figure 6 illustrating the formation of an engraved layer on the uneven substrate after the press moulding.

The container for cosmetics according to the present invention which meets the objectives of the inventors incorporates a substrate generally in the form of a flat sheet, and has formed thereon an engraved layer composed of a photosensitive resin and provided with cavities having a predetermined pattern for packing a cosmetic therein and formed by exposing the resin to light through a mask and washing and removing unexposed areas and preferably covering the top surface of the engraved layer with a surface layer.

In the above- described structure, there is no particular limitation to the substrate serving as the base of the container as far as it satisfies the requirements of mechanical strength for serving as a base of the container and the water resistance in the step of washing in the preparation of an engraved layer.

Examples of the substrate include various metallic sheets, such as aluminium and iron sheets, plastics sheets, and plastics-laminated paper sheets.

It is necessary that the engraved layer for providing cavities for packing a cosmetic therein cures sufficiently through exposure to light, is chemically stable against the cosmetic packed in the cavities, and has a bonding strength with the substrate sufficient for maintaining the mechanical stability under conditions for packing the cosmetic. Examples of the photosensitive resin material for forming the engraved layer satisfying the above-described requirements include cyclic polyisoprene, modified polyamide resin, photopolymerizable acrylic monomer, and polyvinyl alcohol derivatives as described in, for example Japanese Patent Publication Nos. 13018/1980, 34931/1980, 1618/1982 and 49344/1981. These photosensitive resins may be used in liquid form.However, it is preferred to use photosensitive resins which have been dried and sheeted so as to have a predetermined thickness and then moulded, from the viewpoints of workability with respect to the regulation of the dimension, speed of engraving, bubbles, and inclusion of foreign matter.

In the above-described structure, the covering of the surface of the engraved layer with the surface layer is conducted for the following purposes.

One of the purposes is to prevent the inclusion of foreign matter in the cosmetic packed in the cavities.

The wall constituting the cavities comprises a layer made of a photosensitive resin, a layer made of an adhesive, and a substrate, and these materials are substantially nontoxic. Therefore, this kind of container is sufficiently safe. However, in view of the fact that the cosmetic is used by applying it to the skin, it is preferred that the internal surface of the cavities be coated for the purpose of completely preventing the inclusion of foreign matter. For this purpose, it is preferred that acrylic coating, lacquer painting, epoxy coating, varnish or UV ink which has been used for a container of cosmetics or wax which is a raw material of a cosmetic is applied through spraying, immersion, or flood coating and then dried.

Another purpose of the surface coating is to decorate the surface of the relief (top surface).

Since the photosensitive resin layer brings about a curing reaction when exposed to W rays, the layer used is generally transparent. It is a common practice to apply an anti-halation coating so that the exposure light does not scatter towards areas other than those to be exposed. Therefore, the obtained container in the form, for example, of a sheet (a card) exhibits a colour of the halation preventive coating (usually yellow). In this case, the ground colour of the coating may be used as it is. However, colouring treatment for the purpose of emphasizing the colour of the cosmetic through the colouring of the top surface of the relief for distinguishing the areas for packing a cosmetic brings about an advantage that the value added to the goods is enhanced.

A further purpose of surface coating is to impart oil repellency to the top surface of the relief. For example, when a cavity wherein the relief is relatively shallow and has a complicated figure is packed with a cosmetic, the flow levelling property of the contents and the handleability of the packed material up to the solidification and fixation have a great effect on the production efficiency of these kinds of goods. For instance, in order to pack the container with oleaginous matter, it is necessary to take into consideration the surface tension or wettability of the container.Since the surface tension of a wax for a lipstick base and that of a solvent-fluidized eyeshadow composition are 50 to 60 dyne/cm and 30 to 50 dyne/cm, respectively, it is preferred, from the viewpoint of the above-described productivity, to apply an oil-repellent material to the top surface of the container for the purpose of imparting a surface tension lower than that of the abovedescribed cosmetics to the top surface of the vessel.

For example, a silicone resin and a fluororesin are suitably used for this purpose. These resins may be applied through screen printing, transfer coating, roller coating, etc.

The container of the present invention, such as is shown in Figure 1, can typically be produced by the following processes (1) to (4).

(1) As indicated in Figure 2, a negative film is previously prepared so that a single figure or a plurality of figures can be formed. This negative film 1 is put on a photosensitive resin layer 3 laminated onto a substrate 2 (through application or bonding of a sheet) so as to attain a predetermined depth of, say, 0.5 to 0.7 mm and exposed to light.

Subsequently, the photosensitive resin in an unexposed uncured area 32 is thoroughly washed away, and the remaining areas are sufficiently post-cured to completely cure the cured area 31, thereby preparing a container having the desired pattern, such as that shown in Figure 1.

Further, if necessary, the surface of the relief (an area formed by curing the photosensitive resin) is coated through screen printing or the like to prevent the surface tack and attain a colouring effect.

Furthermore, if necessary, for a finishing treatment, the whole surface of the container may be treated with wax, silicone resin, fluororesin, or the like to ensure safety and prevent surface staining.

(2) When the depth of the relief of the container produced in the above-described process (1) is insufficient (the depth of the engraving per exposure is usually about 7 mm), as shown in Figure 3, a plurality of exposed and cured relief pieces 5 (corresponding to an engraved layer free from a substrate), which have been engraved by making use of a negative film having the same pattern as that described above, are laminated on and bonded to each other on the engraved layer 4 having cavities formed by the above process (1), thereby producing a cosmetic container provided with deep cavities.

(3) As shown in Figure 4, a container comprising an engraved layer 6 and a substrate having an even base is preformed according to the above described process (1) by using as the substrate a thermoplastic resin sheet, such as hard polyvinyl chloride, polyethylene, or polypropylene.

Subsequently, the preformed flat thermoplastic resin sheet substrate is recessed at the portions consitituting the base of the cavities by making use of a mould 7, having the same cavities as those described above, by vacuum moulding.

Thus, there is produced a container having a doubled cavity volume.

In this case, the mould 7 used in the vacuum moulding may be one prepared according to the abovedescribed process (1) by making use of the same negative film as that described above and a metallic sheet as the substrate.

(4) Referring now to Figure 5, a first base plate 10 having an engraved layer is initially formed by the above-described process (1) so as to have a negative image opposite to that of the cavity on a metallic plate and a second base plate 9 having an engraved layer similarly formed so as to have a normal negative image prepared. They are used as embossing moulds to mould a base substrate 11 for a container having unevennesses through press moulding.

Then, a photosensitive resin sheet 12 (Figure 6) is fixed on the base substrate 11 having unevenness which has been prepared by press moulding. A normal negative film 1 is accurately put thereon so as not to deviate from the predetermined position, and the exposure and engraving are conducted according to the procedures of the above-described process (1). Thus, there is produced a container having a doubled depth in the same relief depth.

Examples of the present invention, formed by using the processes illustrated by the accompanying drawings, will now be described.

Example 1 A design of a butterfly was drawn within a 97 mmsquare surface (said design being divided into 23 parts defined by veins and contours). A negative film having a negative density of at least 3.0 was prepared by using as a block copy an A2 size art paper having the abovedescribed design on 24 portions thereof.

Then an adhesive and a commercially available photosensitive resin sheet having an antihalation layer applied thereon (Rigilon MX II-145 - a product of Tokyo Ohka Kogyo Co. Ltd.) was applied on a substrate made of steel, and an engraved layer provided with cavities having a relief height of 1.1 mm was formed according to the following procedures.

Exposure conditions: Exposure was conducted for 3 min with a 40-W chemical lamp having a wavelength of 250 to 430 nm.

Washing-out conditions: Uncured water-soluble photosensitive resin was washed out with a brush type washing-out machine (solution temperature of 300C; 5 min).

Draining and drying: Water was drained with compressed air, and drying was conducted at 90 to 1000C for 10 min with a warm air circulation drier.

Post-exposure: Exposure and curing were conducted for 10 min with the above-described chemical lamp.

In this example, the following post-treatment was further conducted to prepare a cosmetic container.

Surface coating: The upper surface of the relief was subjected to silk printing with a black ink, and drying was conducted at room temperature.

Surface protection: A commercially available spray type protective coating "Scotch Guard" (a silicone resin) was sprayed on the whole surface of the product.

Cutting: The product was covered with a masking film and cut into 97 mm-square pieces to prepare 24 card-shaped containers.

The containers for cosmetics thus produced were put on a hot plate, and a lipstick of casting type was heatmelted at 800C and poured into predetermined recesses (cavities) of the containers. The containers were cooled at room temperature to prepare a lipstick cosmetic having a mosaic colourful figure of a butterfly.

Example 2 Eight kinds of designed flower pattern were laid out at equal intervals on an A4 size art paper to prepare a block copy (outside dimension: 53 mm x 86 mm).

Two kinds of negatives, namely an ordinary negative having a density of at least 3.0 and a negative in which the positive and negative are reversed, were prepared from this block copy.

There was prepared an A4 size plate comprising a base substrate made of aluminium (thickness: 0.6 mm) and a photosensitive resin sheet (Rigilon MX II-270 - a product of Tokyo Ohka Kogyo Co. Ltd.) having a relief thickness of 2.1 mm (total thickness: 2.7 mm).

Then, a pair of original plates which are opposite to each other in the recesses were prepared in the same manner as that of Example 1.

Exposure conditions: Exposure was conducted for 4 min with a 40-W chemical lamp having a wavelength of 250 to 430 nm.

Washing-out conditions: Uncured water-soluble photosensitive resin was washed out with a brush type washing-out machine (solution temperature of 300C; 7 min).

Draining and drying: Water was drained with compressed air, and drying was conducted at 1000C for 30 min with a warm air circulation drier.

Post-exposure: Exposure and curing were conducted for 20 min with the above-described chemical lamp.

Thereafter, there was provided a polypropylene-coat paper comprising a paper having a thickness of 0.6 with a 0.1 mm-thick polypropylene layer applied on both surfaces thereof. Emboss moulding was conducted with a press machine equipped with the above-described pair of engraved original plates to prepare a sheet having an embossed area of about 2.0 mm. The pressing was conducted at 800C for 3 min under a pressure of 200 kg/sq. cm.

An adhesive (Nylon Screen Seal Coat; a product of Tokyo Ohka Kogyo Co. Ltd.) was applied to the protrusions of the embossed sheet with a roller, and a photosensitive resin sheet "Elaslon H-200" was put thereon. Further, the above-prepared negative-type negative on which eight patterns had been laid out respectively on eight portions thereof was registered and put thereon. The laminate thus prepared was treated in the same manner as that of Example 1 to produce a container provided with recesses each having a depth of 4 mm in total, namely a relief thickness of 2.0 mm and an embossed area depth of 2.0 mm. This container was subjected to stamping to produce eight card-shaped containers having a predetermined size which were different from each other in the pattern.

The containers thus produced were packed with a liquid-packing type eyeshadow manufactured by Chanson Cosmetic Inc. while changing the colouration. The containers were dried to give a variety of cosmetics which were different from each other in shape and colouration.

Using the processes of the present invention,it is possible to produce easily and quickly a container for cosmetics provided with a cavity having a complicated shape even in small lots, which renders the present invention very useful as a technique capable of producing at low cost various kinds of containers in small quantities.

Claims (9)

1. A container for cosmetics composed of a sheetshaped substrate and an engraved layer having a cavity of a predetermined pattern for packing a cosmetic, prepared by adhering a material comprising a photosensitive resin to said substrate exposing said resin to light through a mask, and washing said resin to remove an unexposed area to form the cavity.

2. A container for cosmetics according to claim 1, wherein said engraved layer has a top surface covered with a surface layer.

3. A container for cosmetics according to claim 1 or claim 2, wherein said surface layer is a coloured layer.

4. A container for cosmetics according to any one of claims 1 to 3, wherein said substrate is made of a metallic sheet, a plastics sheet, or a film-laminated paper.

5. A container for cosmetics according to any one of claims 1 to 4, which further comprises a separate engraved layer having a through-hole cavity having the same pattern and laminated and adhered on said engraved layer.

6. A container for cosmetics according to any one of claims 1 to 4, wherein said substrate is provided with a cavity having a predetermined pattern formed by press moulding or vacuum moulding so as to recess the bottom portion thereof and said engraved layer is formed on said substrate so as to have a through-hole cavity with the same pattern as that of the cavity of said substrate.

7. A container for cosmetics substantially as herein described with reference to the accompanying drawings.

8. A method of forming a cosmetics container wherein a photosensitive resin layer is laid down in a sheet-like substrate, a mask defining a predefined pattern is laid over the resin layer which is then exposed to light to etch the desired pattern into the resin layer, the resin is washed to remove unexposed areas of the resin layer to form cavities in said predetermined pattern, and the cavities are filled with cosmetic materials.

9. A method of forming a cosmetics container substantially as herein described.