JP2005133232A - Method for producing molded pulp product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a molded pulp product having minute and clear uneven parts such as a character, on the surface without increasing the number of processes and a cost. <P>SOLUTION: This method for producing the molded pulp product comprises using a forming mold made by attaching a metal plate having punched holes to a papermaking net and making a pulp mold into paper. In the method for producing the molded pulp product, the metal plate has 0.1mm-0.5 mm thickness. In the method for producing the molded pulp product, the area of each punched hole of the metal plate is 1 mm<SP>2</SP>-50 mm<SP>2</SP>. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for producing a pulp mold molded body having fine and clear uneven portions such as letters on the surface.

Conventionally, pulp molded products have been widely used mainly in various fields, such as a cushioning material for fixing an article to be packaged inside a cardboard box or the like.
The pulp mold molded body is formed using a paper mold formed by forming suction holes on a molding surface of a predetermined shape and covering the molding surface with a paper mesh, and the paper mold is immersed in a pulp slurry, The shape of the papermaking obtained by sucking the slurry through the suction holes and attaching the pulp to the surface of the papermaking mesh, removing the papermaking from the pulp slurry, further dehydrating the pulp, and further drying was transferred. It is a three-dimensional pulp molding.

By the way, in recent years, it has been required to display characters, figures, and the like on the surface of pulp molds due to expansion of applications. For example, according to the Law for Promotion of Effective Utilization of Resources (Recycling Law), pulp molds are classified as “other paper containers”, and if the identification mark indicating the classification is printed or stamped on the product, it is used. Later separation and disposal become easy.
However, since a pulp mold becomes a three-dimensional molded body directly from a pulp slurry as a raw material, it is difficult to perform printing on the surface. If printing is to be performed, it is necessary to use a special printing machine corresponding to a molded product such as an ink jet method, so that it is not practical and hardly performed. Further, for the same reason, display of character figures and the like on the surface by a method of performing engraving with an embossing machine after drying, which is performed on ordinary paper, is rarely performed.

In addition, the pulp mold has an outer shape to which the surface shape of the papermaking is transferred, and it is possible to provide irregularities on the surface of the pulp mold obtained by the shape of the papermaking (see Patent Document 1). Since the surface of the paper mold is usually made of paper mesh, it is impossible to express fine irregularities such as letters.
Moreover, the pulp mold which has a more precise shape can be obtained by heat-pressing in the state pinched | interposed in the mold at the time of drying of a pulp mold manufacturing process. In this way, it was possible to engrave the mold surface by drying in the mold, but in that case, in addition to papermaking, a separate mold for drying was required, and the number of processes and There was a problem that the cost increased. Moreover, it is uneconomical to change the character every time the character is changed.
Patent Registration No. 3126707

  The present invention relates to a production method that does not increase the number of steps and cost of a pulp mold molded body having fine and clear uneven portions such as letters on the surface.

In order to solve the above problems, the present invention has the following configuration.
That is, the first aspect of the present invention is a method for producing a pulp mold molded body, in which a pulp mold is made by using a papermaking mold in which a metal plate having a punched hole is attached to a papermaking mesh during the production of the pulp mold.

  2nd of this invention is a manufacturing method of the pulp mold molded object of this invention 1 whose thickness of a metal plate is 0.1 mm-0.5 mm.

A third invention is a manufacturing method of the 1-2 pulp molded article according to any one of the present invention the area of the perforations in the metal plate is 1mm ² ~50mm ² for one.

  4th of this invention is the pulp mold molded object manufactured by the method as described in any one of 1-3 of this invention.

  According to the present invention, it is possible to obtain a pulp mold molded body having fine and clear uneven portions such as letters on the surface.

Hereinafter, the present invention will be described based on examples.
In the present invention, first, a metal plate M is prepared by punching letters and figures applied to the pulp mold surface (see FIG. 1).
The metal plate is made of any metal such as stainless steel, aluminum, brass, etc., but it is desirable to use a material that is strong and particularly difficult to bend.
Further, it is desirable that the surface of the metal plate has affinity with the pulp fiber and an appropriate amount of pulp is laminated on a portion other than the punched hole portion of the metal plate.
Considering the above two conditions, it is most desirable to use a stainless steel material.

The thickness and size of the metal plate can be arbitrarily selected, but the thickness is preferably about 0.1 mm to 0.5 mm. Especially about 0.3 mm is most preferable. When the thickness is less than 0.1 mm, the thickness of the metal plate is insufficient, and a difference in suction force from the net-making portion hardly occurs, so that there is a problem that a pulp mold having clear irregularities cannot be obtained. There is also a mechanical problem that the strength of the metal plate is weakened. On the other hand, if it exceeds 0.5 mm, according to the experimental results, there is a possibility that a problem that the pulp fiber is difficult to adhere on the metal plate may occur.
Further, it is desirable that the area of the punched holes h of the metal plate is ^{1mm 2 ~50mm} 2 for one. If it is less than 1 mm ^2, the suction force when forming the pulp mold is insufficient, and a problem arises that a pulp mold having clear irregularities cannot be obtained. On the other hand, if it exceeds 50 mm ² , there is a possibility that the problem that the strength of the metal plate becomes weak may occur.
Moreover, when the size of the metal plate is approximately square, one having a side of about 10 mm to 50 mm square is preferably used. If the side is less than 10 mm, the area occupied by the hole for fixing the metal plate to the paper net and the punched hole for representing characters, symbols, figures, etc. is relative to the size of the metal plate There is a problem that the strength is inferior because it becomes large. On the other hand, if it exceeds 50 mm, the metal plate part is too large and does not deposit on the pulp fiber well on the surface of the net, or the uneven part of the manufactured pulp mold surface becomes too large and the mold strength deteriorates. Problems can occur.
In addition, when the present invention is used for displaying an identification mark on a packaging container based on the Law for Promotion of Effective Utilization of Resources, if the regulation value of the size of the identification mark display in the law is stamped / embossed, it is vertically long Since it is 8 mm or more, a metal plate of about 10 mm to 20 mm square is preferably used.

  Next, the metal plate M obtained as described above is fixed to the papermaking mesh (2) on the surface of the papermaking mold (1) (see FIG. 2). As a means for fixing, a method of fixing to a papermaking net with a pin, a method of binding to a papermaking net with a wire or the like, a means such as fixing with a fine bolt / nut having a diameter of about 1 mm are used. Among them, fixing with fine bolts and nuts is most desirable because it is easy to remove.

Usually, the above-mentioned net is a coating on the surface of a convex molded body (3) having a vent having a shape similar to the target pulp mold shape, as described above. Called a type. The papermaking mold is immersed in the pulp slurry, the slurry is sucked from the suction holes to adhere the pulp (p) to the surface of the papermaking mesh (see FIG. 3), and the papermaking mold is taken out from the pulp slurry and further sucked to dehydrate the pulp. .
Usually, as a next step, the pulp laminated with a concave mold called a mold (4) matched to the outer shape of the molded body is sandwiched, and the pulp mold is pressed with air from the vent inside the convex mold. It transfers to a mold (refer FIG. 4), and a pulp mold molded object (P) is completed through a predetermined drying process after that (refer FIG. 5, FIG. 6).

In the present invention, since a metal plate having a punched hole is attached to the surface of the papermaking net, a difference in suction force occurs between the punched hole portion and the metal plate surface, and agglomerates on the papermaking net. A significant difference in pulp thickness is obtained. That is, the punching hole portion of the metal plate produces a suction force equivalent to that of the papermaking net portion where the metal plate does not exist, and the pulp material having the same thickness as the papermaking mesh portion is laminated, but the metal plate not punched Since almost no suction force is generated in the portion, the pulp raw material is laminated only very thinly.
As a result, a clear unevenness is generated on the surface of the pulp mold, and by using this, it is possible to display clear characters, symbols, and the like.
In addition, when this display is an identification mark in accordance with the Law for Promotion of Effective Utilization of Resources, it is an aid when the waste is disposed of by the consumer.

  The present invention is a method for producing a pulp mold molded body having fine and sharp irregularities on the surface, and particularly when it is necessary to display characters, symbols, etc. on the surface of the pulp mold molded body, the container recycling method It is preferably used when an identification mark based on the above is applied.

It is a figure which shows the metal plate which has the punching hole of this invention. It is a figure which shows the papermaking machine which attached the metal plate which has the punching hole of this invention. It is the figure by which the pulp raw material was laminated | stacked on the papermaking type | mold of this invention. It is the figure by which the pulp was pinched | interposed between the papermaking type | mold of this invention, and a shaping die. It is sectional drawing of the pulp mold molded object which has an uneven | corrugated | grooved part on the surface obtained by this invention. It is a top view of the pulp mold molding which has an uneven | corrugated | grooved part on the surface obtained by this invention.

Explanation of symbols

M: Metal plate, h: Punched hole, p: Pulp, P: Pulp molded body, 1: Papermaking, 2: Papermaking, 3: Convex shaped body, 4: Molding

Claims (4)

  A method for producing a pulp mold molded article, wherein, during the production of a pulp mold, the pulp mold is made by using a papermaking mold in which a metal plate having punched holes is attached to a papermaking net.   The method for producing a pulp mold product according to claim 1, wherein the metal plate has a thickness of 0.1 mm to 0.5 mm. Method for producing a pulp molded article according to any one of claims 1-2 in which the area of the perforations in the metal plate, characterized in that the one is a 1mm ² ~50mm ^2. The pulp mold molded object manufactured by the method as described in any one of Claims 1-3.

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