JPS61226137A - Production of casting mold, casting mold and article - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION BACKGROUND AND SUMMARY OF THE INVENTION The present invention relates to a method of deforming a mold surface texture to impart a desired pattern to a cast article and, inter alia, a method for modifying a mold surface texture to impart a desired pattern to a cast article and The present invention relates to cast articles made with treated mold surfaces in which the surface of the casting is textured to give the masonry a distinctive surface.

Traditionally, cast plastic articles have been provided with various surface textures by processing the molds in which the articles are formed. Furthermore, in the production of cast articles, the surface texture of the resulting product has often been modified by treating the surface of the article by chemical etching, mechanical deformation, etc. after casting. Although the aforementioned methods have been useful for many types of cast articles when the cast articles are used in architectural structures as wall surfaces, conventional surface texture modification methods
They are particularly difficult to use when pigments are included in the casting composition and when the casting composition contains substantial amounts of polymerizable resins, such as polyester or epoxy resins.

In mass production of individual articles, each article having a cast surface, it is impractical to process the articles individually after casting. This is because this method has a significant impact on manufacturing costs.

Furthermore, the individual processing of articles after casting invariably very easily introduces non-uniformities in the product as a result of the processing steps required after curing of the article in the mold.

Accordingly, it is an object of the present invention to provide a method of manufacturing a mold surface such that during the casting of an article, the article is formed and cured in the mold while the mold forms a pattern on the surface of the cast article. It is a purpose.

In summary, the present invention utilizes mild steel mold elements and first masks and coats selective surfaces such that the mold surfaces imprint the desired pattern on the cast article.

The texture of the mold surface with the mask material applied thereto is then deformed by sandblasting onto the uncoated mold surface. The mask is then removed and the mold is pre-cleaned in order to plate the entire mold surface with metal, for example nickel. Then, using the plated mold surface,
The cast article is molded from a plastic resin material, such as an epoxy resin composition or a polyester resin composition, which may optionally contain pigments and fillers, such as sand.

In a preferred embodiment, the plastic composition is cured in an oven by placing the plastic material in a flowable state in a mold and placing supporting members, such as masonry units, brackets, gilt copper, etc., on top of the plastic composition. During this process, the composition is cured and bonded to the surface of the support member. The portion of the composition facing the mold surface will then have the surface texture defined by the masking material so that its outer surface will have the desired pattern in the finished product.

It has been found that when using the method of the invention, the resulting product gives a unique appearance to the casting surface. In particular, the pattern is observed to change as the viewer moves across the surface and as the angle of illumination to which the surface is exposed changes.

These and other advantages will become apparent upon consideration of the following description in conjunction with the accompanying drawings.

[Detailed description of the invention]

The present invention is applicable to, for example, U.S. Pat. No. 2,751,775, U.S. Pat.
4,031,289 and 4,329.82
It is particularly useful in the field of coating masonry construction units with unsaturated polyester resins, as disclosed in No. 2. As described in the first four of the above-mentioned U.S. patents, relatively low-grade masonry units can be coated to avoid the need for any finishing after the walls are built with blocks. Can form decorative and durable surfaces. U.S. Pat. No. 4,329,822 describes a type of support member that can also provide a finished surface.

To enhance the decorative appearance of the coating of such blocks or other members, the present invention provides a masking material 12 on selective portions of the surface of the mold 10, as shown in FIG. Deform the mold surface of the IO. Other parts, for example part 14 of the mold surface, remain uncoated. The mold 10 has a conventional side flange 16 surrounding the (main) surface of the mold. Next, with the masking material 12 applied to the desired portions of the mold surface of the mold 10, the uncovered areas of the mold are removed. 14, the surface texture of the area is changed by forcibly blowing a medium, for example sand, using means such as a nozzle 18. Although a sand plaster is the preferred machine for altering the texture of the non-masked surface of mold 10, it will be apparent to those skilled in the art that other surface texture modification techniques may also be used.

Referring now to FIG. 2, according to the present invention, mask material 12
from the mold surface and then thoroughly clean the mold. The mold 10 is then subjected to a plating process to deposit a suitable metal onto the mold surface, including the sandblasted portions. Conventional electrolytic plating methods may be used, but in order to minimize the risk of contamination of the metal that adheres to the mold with impurities that will later affect the resin film to be cast in the mold, electroless plating is used. It has been found that it is preferable to use plating.

The preferred metal to be deposited on the mold surface is nickel deposited using a hypophosphite solution.

Many plating baths have been proposed, and "Explanation and Specifications of Plating Finishing (Metal Finishing Gr.
idbook and Director) J (Metals and Plastics Publications, Inc.)
Hackensack, New Chassis (annually). For details on the method and characteristics of electroless plating, please refer to [
Kirk-Othme Encyclopedia of Chemical Technology
r Encyclopedia of Chemistry
al Technology) J (3rd edition, Vo
l, 8, John Wiley & Son Co., 738
~750 pages, 1979).

After plating mold 10 with a metal such as nickel, mold 10 is ready to form a cast article.

Referring to FIG. 3, a casting composition, which may include resins, pigments, fillers, and plasticizers as described in the aforementioned patent, is ground to a fluid state such as a slurry and then mold 10. and spread over a suitable internal surface of mold 10. In one preferred embodiment, upon insertion of the masonry block 30 into the mold 10, the weight of the block 30 will distribute the composition 28 substantially uniformly over the target surface of the mold 10. In many applications, it is desirable to configure the casting composition to be substantially liquid to promote uniform distribution over the mold surface. Using the surface of block 30 inserted into mold 10 as shown in FIG. 3, mold 10 and block 30 are heated together with the coating composition therebetween to cure casting composition 28. In this regard, the mold 10 is made of mild steel.
That is, it is preferably made of steel with a maximum carbon content of no more than 0.25%. This is because mild steel has better thermal conductivity than stainless steel. Thus, with a mild steel mold and nickel plated as described above, an excellent finish is achieved on the cured resin 28 with a faithful reproduction of the pattern based on the lower surface texture of the mold 10.

Referring now to FIG. 4, the effect of patterning the surface of mold 10 with a stream of abrasive or surface modification medium and plating with solution in tank 20 to form a metal coating 24 on patterned surface 24. It is an enlarged sectional view showing typically. Viewing the cast surface of composition 28 causes an observer to approach the cast article;
When passing by, the pattern on the surface looked different depending on the viewing angle. This is thought to be due to the fact that the surface structure of the metal remains as rough as shown schematically in Figure 4, but the later metal plating process flattens it into a Mi texture. . Thus, when looking straight at the pattern on the casting surface, the portions of the mold 10 that correspond to the roughened areas 14 tend to blend in with other areas, but as the observer moves, the casting composition 28
It turns out that if you look at it from an angle, you can see the pattern more clearly. This effect was observed to create interesting patterns and unusual colors that change when the surface is at ground level and a person moves 360 degrees around the surface. This novel effect has a very pleasing decorative appearance and is particularly noticeable when the casting composition contains colored pigments.

Having thus described the invention, it will be apparent to those skilled in the art that various modifications may be made thereto without departing from the spirit and scope of the invention as set forth in the claims.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram explaining the present invention in detail, FIG. 2 is a partially cutaway elevational view explaining another process of the present invention, FIG. 3 is a partial sectional view showing the casting process of the present invention, and FIG. , 4 is a partially enlarged sectional view of the casting surface after plating. 10...Casting member, 12...Mask material, 1
4...uncovered area, 16...side flange,
18... Nozzle, 20... Tank, 24
...Metal film, 26...Patterned surface, 28.
...Casting composition, 30...block.

Claims (1)

[Claims] 1. A method for producing a mold surface for patterning a molded article, comprising: applying a masking material to the mold surface to cover selected surface areas of the mold; directing a deformation medium to deform the surface texture of the uncoated areas of the mold surface, removing the masking material from the mold surface, and then coating the mold surface, including the unmasked areas and the previously masked areas, with metal. Including mold surface manufacturing method. 2. The method of claim 1, wherein the step of directing the surface modification medium against the mold surface comprises mold surface sandblasting. 3. The method according to claim 1, wherein the coating step includes a mold surface plating step. 4. The method according to claim 1, wherein the mold surface coating step includes the step of electrolessly plating metal on the mold surface after cleaning the mold surface. 5. Including the process of using nickel as the plating metal,
The method according to claim 4. 6. The method according to claim 1, comprising the step of using a metal mold. 7. The method of claim 1, comprising the step of using a mold made substantially of mild steel. 8. The method of claim 1, comprising the step of using a mold made substantially of hot rolled steel. 9. The method of claim 1, comprising the step of using a mold made substantially of cold rolled steel. 10. The method of claim 1, comprising the step of using a mold made substantially of aluminum. 11. A method of manufacturing a mild steel mold surface for forming a pattern on an article to be formed in the mold, comprising: applying a masking material to the mold surface to cover selected surfaces of the mold; and sandblasting the mold surface. After removing the masking material from the selected surfaces and cleaning the mold surface, nickel is applied to the mold surface including the pre-masked areas as well as the unmasked areas. A method for manufacturing mild steel mold surfaces that includes the process of attaching. 12. A mold for an article having on one surface at least two areas of different surface areas, the surface of which is a first surface area with a smooth texture and a second surface area with a rough texture. and wherein both of these surface areas are coated with a metal layer. 13. The mold of claim 12, wherein the metal layer is substantially nickel. 14. The mold according to claim 12, wherein the mold is made of steel. 15. The mold according to claim 13, wherein the steel has a carbon content of not more than 0.25%. 16. a first surface region having a smooth texture;
a second surface region with a rough texture, and both of these surface regions are coated with a metal layer; Goods. 17. The article according to claim 16, wherein the article is a resin composition containing polyester. 18. The article according to claim 16, wherein the article is a resin composition containing epoxy. 19. The article according to claim 16, wherein the resin is adhered to the surface of the support member. 20. The article according to claim 17, wherein the resin is adhered to the surface of the support member. 21. The article according to claim 19 or 20, wherein the support member is a masonry unit. 22. The article according to claim 19 or 20, wherein the support member is a wire mesh. 23. The article according to claim 19 or 20, wherein the support member is a bracket. 24. The article of claim 16, wherein the article is a sand-filled polyester resin composition. 25. The article of claim 24, wherein the weight of the sand is 50% by weight of the composition. 26. The article of claim 17, wherein the composition comprises a pigment. 27. The article of claim 18, wherein the composition comprises a pigment.