JPS6243774B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a mold roll, and more particularly to a method for manufacturing a mold roll, and more specifically, a method for manufacturing a mold roll, and more specifically, a method for manufacturing a mold roll, and more specifically, a method for manufacturing a mold roll to obtain a desired uneven surface shape of a natural or artificially processed object such as a natural product, paper cloth, or textile. The present invention relates to a method of manufacturing a mold roll that can reproduce the process extremely faithfully. Conventionally, in order to manufacture the metal rolls used for embossing thermoplastic resins, an inverted shape of the target uneven surface pattern (hereinafter referred to as the original) is copied onto a medium as faithfully as possible, and based on this, A small-diameter roll with a concave-convex pattern, which is the inverse of the concave-convex pattern of the original, called a mill type, is made on its surface, and the mill type is pressed against the iron core while applying a corrosive liquid to create an engraved roll. I was there. However, regarding mold rolls created in this way, (1) the transfer of the uneven surface pattern that becomes the manuscript to the mill requires the skill of a skilled roll engraver, but it is satisfactory when the pattern is complex. (2) Pursuing faithful reproduction of the manuscript would require a huge amount of time and production costs would be extremely high; and (3) It is generally made using a small mill. As a result, patterns with limited dimensions are repeated on the mold roll in both the circumferential and axial directions, resulting in unexpected pattern irregularities. Alternatively, the original is photographed to create a reversed photographic image of the original on a film, and a photosensitive corrosion-resistant coating is applied to the iron core and dried, then the film is wrapped around it, exposed to light, and developed. A method has also been proposed in which the coating material in the unexposed area is removed and the exposed core material is etched with a special etchant to create a mold roll. If etching is planned, accidents such as side etching of the core material will progress and the edges of the design will be distorted, and accidents such as the edge of the design will be likely to occur. Expression is impossible. We purposely used multiple photographic film inversion images and applied the anti-corrosion coating each time.
Even if we try to reproduce the manuscript as faithfully as possible by repeating exposure, development, and etching, the process is complicated and time-consuming, and the slope from the convex part to the concave part mentioned above gives a step-like expression. The drawback is that it is only a complete image, so it is difficult to faithfully reproduce the manuscript.

SUMMARY OF THE INVENTION An object of the present invention is to overcome the above-mentioned drawbacks and to provide a method for manufacturing a mold roll that can reproduce the uneven pattern of a document extremely faithfully in a short period of time.

The present invention will be explained in detail below according to the manufacturing process with reference to the drawings.

First, as shown in FIG. 1, a document 1 is fixed on a flat plate 3 such as a surface plate by appropriate means, and a mold-making fluid resin 2 is spread on the document and left. and harden. This mold-making resin is, for example, a silicone resin mixed with a hardening agent, and has appropriate fluidity when spread on the uneven surface of the original, and can completely penetrate into the minute recesses of the original, and is left for a predetermined period of time. Then, it will harden naturally, allowing you to faithfully model the delicate uneven patterns on the original. After the resin has hardened, the original is peeled off to obtain a resin plate (hereinafter referred to as a matrix) having a concavo-convex pattern that is the inverse of the concave-convex pattern of the original. As shown in Fig. 2, a hollow cylindrical manuscript 1' (such manuscripts are made of, for example, a columnar body with engravings on the circumferential surface, a cylinder covered with a seamless cylindrical fabric, or a cylinder with paper wrapped around its surface). When using a cylindrical inner mantle 4 having an outer diameter that approximately matches the inner diameter of the original, the cylindrical inner mantle 4 is inserted into the hollow part of the original and circumscribes this outer protrusion to support the original 1'. do. This inner mantle can be omitted if the hollow cylindrical document 1' is structurally strong enough (for example, made by pasting bark on the surface of an iron or resin pipe with an adhesive). Then, an appropriate gap 7' is formed from the surface of this original document 1', and a mantle 5' is disposed.
A mold-making resin can be flow-spread into this gap and cured to obtain a mother mold.

The thus obtained resin plate or resin cylindrical matrix is fixed tightly to the inner surface of the mantle 5 with the molded surface facing inside, that is, the surface without uneven patterns, as shown in FIG. A core material 6 having an outer diameter that forms a desired gap 8 in the center with the molding surface of the mother mold.
, align the center lines of the mantle and core material, and fix. This matrix can also be used as a mold for casting, and if necessary, a suitable resin is poured onto this matrix and hardened to reproduce the same uneven pattern as the manuscript, which is then used as a casting mold. It is also possible.

Next, a low melting point metal that will form the mold surface is injected in a molten state into the gap 8 formed between the core material 6 and the matrix 7. Such low melting point metals have a temperature range whose upper limit is the heat resistance temperature of the matrix resin material and whose lower limit is the melting and softening temperature of the thermoplastic resin processed with the mold roll,
Preferably, it is an elemental metal or an alloy thereof having a melting point within a temperature range of 100 to 500°C. Such metals or alloys include single metals such as lead, tin, and zinc, as well as Pb-Sn alloys known as solders and Pb-Sn-Sb alloys known as type alloys, such as those used for casting. Zinc alloy (e.g., product name: ZAS
etc.) and alloys such as bismuth-based alloys (eg, SK alloy, etc.).

After pouring these molten metals or alloys, the molten metal can be cooled naturally or left in a furnace where the cooling time can be controlled by cooling with a cooling device to cool and solidify the molten metal, and then the mother mold is removed. A metal roll is obtained in which a mold is integrated with a core material, and the mold has an inverted uneven pattern on its surface that can reproduce the uneven pattern of an original with great fidelity.

When injecting molten metal, preheating the matrix and core material to an appropriate temperature, for example, from the melting point of the molten metal to a temperature 100°C lower than the melting point, will prevent the molten metal from flowing. Since the properties of the molten metal are maintained, the molten metal can satisfactorily reach even the minute uneven pattern portions of the matrix, further improving the reproducibility of the original. Furthermore, if the mold roll is required to have surface hardness, the roll surface may be plated with hard chrome to obtain a mold roll having the desired surface hardness.

According to the above method, a metal roll in which the mold and the core material are integrated can be obtained, but when the mold part formed by molten metal is formed into a sleeve shape and used as a mold roll. It can also be fixed to the core material with a key or the like. If sleeve-shaped molds with various uneven pattern surfaces are prepared, they will not only be easier to handle than those with a core material, but will also be cheaper to manufacture, and will also make it easier to use only the molds during embossing work. Since they can be replaced, work efficiency can be improved.

The present invention will be explained in more detail with reference to the following examples.

Example A molding resin having the following composition is used.

(Weight) KE-1400RTV (trade name, silicone resin manufactured by Shin-Etsu Chemical; viscosity 1200poise) 100 parts Catalyst 1400 (trade name; manufactured by Shin-Etsu Chemical) 10 parts A manuscript made by combining the above resin composition with cedar bark (30× 30 cm) to a thickness of approximately 4 m/m, and after curing, the manuscript was peeled off from the cured resin plate to obtain a matrix in which the concave-convex pattern of the cedar bark of the manuscript was inverted. After treating the patterned surface of the mother resin plate thus obtained with a release agent, a resin composition having the following composition was spread on the patterned surface of the mother resin plate to a thickness of approximately 5 m/m, and was cured. Thereafter, the mother mold was peeled off to obtain a mold resin plate for metal roll molding.

(Weight) KE-12RTV (trade name, silicone resin manufactured by Shin-Etsu Chemical; viscosity 120poise) 100 parts Catalyst RM (trade name, manufactured by Shin-Etsu Chemical) 1 part
Adhere closely to the inside of a steel pipe (mantle) with a wall thickness of 5 m/m with the pattern side facing outward. and outer diameter 75m/
In this case, an iron pipe with a wall thickness of 5 m/m was used as a core material and was arranged and fixed so that the center line of the mantle and the center line of the core material matched. Next, this was placed in a furnace at a temperature of 200℃, and after controlling the temperature, 350℃ of Pb-Sn-Sb alloy (type alloy) was heated.
The melt kept at ℃ is injected into the gap (width approx. 7.5m/m) formed between the core material and the resin plate for the mold, and after solidifying by natural cooling, the resin plate for the mold is When peeled off, a mold roll was obtained in which a pattern was formed on the roll surface that was a faithful inversion of the original uneven pattern having the same depth and shape as the master mold.

The mold roll obtained in this way is pressed and pressed against a heated and melted PVC sheet (thickness 200μ) lined with paper, and when peeled off, the uneven pattern of the cedar bark of the manuscript is reproduced on the PVC sheet with great fidelity. A reproduced cedar bark pattern was obtained.

[Brief explanation of the drawing]

FIGS. 1 to 3 are diagrams for explaining the manufacturing process of a mold roll according to the present invention. Codes in the figure: 1... Original, 2... Resin for mold making, 3...
Flat board, 4... Inner mantle, 5... Outer mantle, 6... Core material, 7...
Mother mold, 8... air gap for mold.

Claims (1)

[Claims] 1. A fluid curable resin is poured onto the surface of an object having a desired uneven pattern, the uneven pattern is molded into a matrix, and the surface of the thus obtained matrix without the uneven pattern is shaped into a cylindrical shape. A cylindrical core material having an outer diameter smaller than the inner diameter of the mantle is fixed tightly to the inner surface of the mantle, and then fixed in alignment with the center line of the mantle, and is inserted into the gap between the patterned surface of the matrix and the outer surface of the core material. A method of manufacturing a mold roll, which is characterized by melting and injecting a low melting point metal or alloy and cooling and solidifying it.