JP2019183350A - Method for producing pulp molded body - Google Patents

Abstract

To provide a method for producing a pulp molded body capable of changing the surface expression of a manufactured product.SOLUTION: A method for producing a pulp molded body in this invention comprises a pulp mold intermediate forming step for forming a pulp mold intermediate in a recycled paper recycled pulp slurry by a pulp mold method, a dehydrating step of dehydrating the formed pulp mold intermediate to make the moisture content 50 to 80%, a mold preparation step of preparing a mold having a temperature adjusting means and a pressurizing amount adjusting means, and a finishing molding step, in which with the prepared mold, the pulp mold intermediate is press-molded at a predetermined temperature and a predetermined pressure amount to obtain the pulp molded body. This method is characterized in that a pulp molded body having a different surface expression is produced by changing the predetermined temperature and/or the predetermined pressure amount.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for producing a pulp molded article.

The present applicants proposed a manufacturing method and a manufacturing apparatus of a laminated pulp mold in a previous patent application (Japanese Patent Application No. 2017-104087).
In the proposed method for producing a laminated pulp mold, a pulp mold first layer is formed by a pulp mold method in a recycled paper recycled pulp slurry containing 0 to 5% by mass of cellulose nanofibers, and then a pulp mold intermediate is dehydrated, Subsequently, a pulp mold second layer is formed on the surface of the pulp mold first layer by a pulp mold method in a cellulose nanofiber slurry containing recycled paper recycled pulp of 1 to 30% by mass. Finally, dehydration and drying are performed. To produce a laminated pulp mold.

Japanese Patent Application No. 2017-104087

The inventor of the present application has been intensively researching pulp molds using recycled paper recycled pulp slurries in relation to the above manufacturing method. Even if the same recycled paper recycled pulp slurries are used, the mold at the final stage is used. In the molding process, when the molding conditions (pressurization amount, temperature) were changed variously, it was found that the surface appearance of the manufactured product changed.
The present invention is based on this finding, and an object of the present invention is to provide a method for producing a pulp mold product capable of changing the surface expression of a manufactured product.

The said subject is achieved by the manufacturing method of the pulp mold molded object of the structure of following (1)-(5) by this invention.
(1)
A pulp mold intermediate forming step of forming a pulp mold intermediate in a recycled paper recycled pulp slurry by a pulp mold method;
A dehydration step of dehydrating the formed pulp mold intermediate to a moisture content of 50 to 80%;
A pulp preparing step of preparing a mold having a temperature adjusting means and a pressurizing amount adjusting means, and the pulp mold intermediate is press-molded at a predetermined temperature and a predetermined pressurizing amount by the prepared mold, It has a finish molding process to make a molded body,
A pulp mold molded body having a different surface expression is manufactured by changing the predetermined temperature and / or the predetermined amount of pressurization. A method for manufacturing a pulp mold molded body.
(2)
The method for producing a pulp molded article according to (1), wherein the predetermined pressurization amount is a product of a pressure value and a time.
(3)
(1) The method for producing a pulp mold product according to (1) or (2), wherein the predetermined pressurization amount is set within a predetermined pressurization amount range.
(4)
The method for producing a pulp mold product according to any one of (1) to (3), wherein the predetermined time is set within a predetermined time range.
(5)
The method for producing a pulp mold product according to any one of the above (1) to (4), wherein the amount (in a dry state) of the used paper pulp in the used paper recycled pulp slurry is 50% or more.

  In the method for producing a pulp mold molded body of the present invention, as described above, a pulp mold molded body having a different surface expression is produced by changing the predetermined temperature and / or the predetermined pressurizing amount in the finish molding step. For example, it can be applied as a mount having a different surface design.

It is the schematic of the shaping | molding apparatus used for the manufacturing method of the pulp mold molded object by embodiment of this invention. It is a figure which shows the example of the pulp mold molded object manufactured by the manufacturing method of the pulp mold molded object by embodiment of this invention. It is a figure which shows the example of the pulp mold molded object manufactured by the manufacturing method of the pulp mold molded object by embodiment of this invention. It is a figure which shows the example of the pulp mold molded object manufactured by the manufacturing method of the pulp mold molded object by embodiment of this invention. It is a figure which shows the example of the pulp mold molded object manufactured by the manufacturing method of the pulp mold molded object by embodiment of this invention.

Hereinafter, the manufacturing method of the pulp mold molded object by embodiment of this invention is demonstrated.
FIG. 1 is a schematic view of a molding apparatus 10 used in a method for producing a pulp mold product according to an embodiment of the present invention.
The molding apparatus 10 includes a mold 20, and the mold 20 includes a lower mold 22 that serves as a base and an upper mold 24 that can be raised and lowered relative to the lower mold 22. The molding surfaces 22a and 24a of the upper mold 22 and the lower mold 24 may have any shape. For example, a cavity may be formed by the molding surfaces 22a and 24a.

  The upper mold 24 is moved up and down by a hydraulic cylinder 32 driven by a hydraulic cylinder driving means 30. The hydraulic cylinder driving means 30 is configured such that its hydraulic oil introduction amount is adjusted by a hydraulic cylinder control circuit 34 connected to the hydraulic cylinder driving means 30 so that driving is controlled. The hydraulic cylinder driving means 30 controlled by the hydraulic cylinder control circuit 34 controls the pressing force of the hydraulic cylinder 32 against the pulp mold intermediate W disposed on the lower mold 22.

  The hydraulic cylinder control circuit 34 includes a timer 36, and controls the driving time of the hydraulic cylinder driving means 30 based on the time measured by the timer 36. Thereby, the pressing time of the pulp mold intermediate W is controlled.

  Heaters 26 and 28 are disposed inside the lower mold 22 and the upper mold 24, and the amount of heat generated, the time of heat generation, and the like are controlled by a heater control circuit 38. The heater control circuit 38 and the hydraulic cylinder control The circuit 34 may be constituted by a single control means.

Next, the manufacturing method of the pulp mold molded object by embodiment of this invention using the said shaping | molding apparatus 10 is demonstrated. First, thickness 3-8mm is used with a well-known pulp mold manufacturing apparatus using a used paper recycled pulp slurry. A non-dehydrated plate-like pulp mold intermediate W is produced. After the non-dehydrated pulp mold intermediate is formed, dehydration by suction is performed. This dehydration is performed for about 5 to 15 seconds, and the moisture content of the pulp mold intermediate is set to 50 to 80%, preferably about 65 to 70%. The thickness of the pulp mold intermediate W after the dehydration is about 1 to 5 mm.

After this dehydration, the pulp mold intermediate W dehydrated as described above is placed on the lower mold 22 as shown in FIG.
After placement, the hydraulic cylinder driving circuit 30 is driven by the control of the hydraulic cylinder control circuit 34 to lower the upper mold 24 and press the pulp mold intermediate W for a predetermined time with a predetermined pressing force. To do.
During this time, the heater control circuit 36 controls the heat generation temperature (heat generation amount) of the heaters 26, 28, and the pulp mold intermediate W is pressed at a predetermined temperature under a predetermined pressing force for a predetermined time to obtain a plate shape. A pulp mold product is obtained.
In the above, by changing the pressing force value, pressing time, and pressing temperature to predetermined values, pulp molded products having different surface expressions are obtained.

  First, an undehydrated plate-like pulp mold intermediate W having a thickness of about 7 mm was manufactured using a recycled pulp slurry of used paper by a known pulp mold manufacturing apparatus, and dewatering was performed by suction. This dehydration was performed for about 15 seconds, and the moisture content of the pulp mold intermediate was about 65 to 70%. The pulp mold intermediate W after dehydration had a length of 730 mm, a width of 510 mm, and a thickness of about 4 to 5 mm. Four pieces of the above pulp mold intermediate were prepared and used as samples of Examples 1 to 4, respectively.

  Waste paper recycled pulp slurry is prepared by first dissolving waste paper (confidential documents, newspapers, cardboard, etc.) with a pulper, and then removing foreign substances such as unsuitable dust from the raw material with a foreign matter removing device. Got.

  The sample is placed on the lower mold 22 as shown in FIG. 1, and the pulp mold intermediate of the sample is pressed under the conditions shown in Table 1 to obtain pulp mold molded bodies of Examples 1 to 4 Got. The surface photographs of these pulp mold products are shown in FIGS.

  As can be seen from FIGS. 2 to 5, pulp moldings having different surface expressions can be obtained by variously changing the pressing conditions during molding as described above.

DESCRIPTION OF SYMBOLS 10 Pulp mold manufacturing apparatus 20 Mold 22 Lower mold 24 Upper mold 26 Heater 28 Heater 30 Hydraulic cylinder drive means 32 Hydraulic cylinder 34 Hydraulic cylinder control circuit 36 Timer 38 Heater control circuit W Pulp mold intermediate body

Claims (5)

A pulp mold intermediate forming step of forming a pulp mold intermediate in a recycled paper recycled pulp slurry by a pulp mold method;
A dehydration step of dehydrating the formed pulp mold intermediate to a moisture content of 50 to 80%;
A pulp preparing step of preparing a mold having a temperature adjusting means and a pressurizing amount adjusting means, and the pulp mold intermediate is press-molded at a predetermined temperature and a predetermined pressurizing amount by the prepared mold, It has a finish molding process to make a molded body,
A pulp mold molded product having a different surface expression is produced by changing the predetermined temperature and / or the predetermined amount of pressurization. A method for producing a pulp mold molded product.   The method for producing a pulp molded article according to claim 1, wherein the predetermined pressurization amount is a product of a pressure value and a time.   3. The method for producing a pulp molded article according to claim 1, wherein the predetermined pressurization amount is set within a predetermined pressurization amount range.   4. The method for producing a pulp molded article according to claim 1, wherein the predetermined time is set within a predetermined time range.   The method for producing a pulp mold product according to any one of claims 1 to 4, wherein an amount (in a dry state) of used paper pulp in the used paper recycled pulp slurry is 50% or more.