JP2579875B2 - Apparatus and method for manufacturing sheet-formed article - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for producing a paper-formed article.

[0002]

2. Description of the Related Art In recent years, for the packaging of household electric appliances, precision instruments, foods, etc., papermaking components are formed from a foaming synthetic resin material or a papermaking molding material liquid in which papermaking materials such as pulp are dispersed. What is scraped and formed into a predetermined shape is used. Of these, those made from pulp are mainly used as packaging containers for foods such as small electric appliances and eggs.

Conventionally, as a manufacturing apparatus for manufacturing a papermaking molded article used for the above-mentioned packaging container or the like, a papermaking component in a pulp raw material liquid is taken out, and then water in the papermaking component is dehydrated. A papermaking molding mechanism for forming a hydrated paper-molded article of a predetermined shape, and a dry-molding space is formed when the mold is clamped, and moisture remaining in the hydrated paper-molded article from the dry-molding space and water vapor from which the moisture has evaporated are discharged. With the hot water-pressed molded article obtained by the above-mentioned papermaking molding mechanism by a pair of male and female press dies provided on the press surface with a discharge hole,
An apparatus comprising a dry forming mechanism for suctioning the inside of the dry forming space from the discharge hole under reduced pressure and drying and forming the hydrated paper-formed product is used.

[0004]

However, the discharge hole provided in such an apparatus has a small diameter because it is merely formed by dispersing a plurality of through-holes substantially uniformly and punching it in a press die. If it is too much, there is a problem that the removal of moisture and water vapor is poor. If moisture or water vapor is not well drained, drying efficiency will be reduced.In addition, the water contained in the hydrated paper-made molded product will evaporate due to heating, and the water vapor generated will increase the pressure inside the molded product. There is a risk that the molded article will burst near the micropores due to the pressure difference (the pressure near the surface of the molded article drops sharply because the vicinity of the micropores is suctioned under reduced pressure).

[0005] For this reason, various measures have been devised to satisfactorily discharge water or water vapor by simply increasing the diameter of the discharge hole or increasing the number of discharge holes. In the case where the size is increased, the raw paper-dried papermaking component that is not completely fixed on the surface of the paper-formed article at the time of hot pressing enters the discharge hole, and the papermaking component enters the discharge hole (that is, inside the press mold). When dried, the dried papermaking component sticks to the peripheral wall of the discharge hole, and the discharge hole gradually becomes clogged, so that there is a problem that the press mold must be frequently cleaned. On the other hand, if the number of discharge holes is simply increased, the effective area of the heated surface for drying the hydrated paper molded article by heating decreases, and it becomes impossible to perform drying efficiently, or a mold is formed. There is a problem that the cost is too high.

[0006] The present invention has been made in view of the above points,
An object of the present invention is to provide an apparatus for manufacturing a paper-formed article capable of satisfactorily discharging water and steam during drying, and to provide a method for manufacturing a paper-formed article that can effectively discharge water and steam during drying. The purpose is to:

[0007]

Means for Solving the Problems The apparatus for producing a papermaking molded article according to the present invention is a papermaking machine for obtaining a papermaking molding product by removing a papermaking component from a papermaking molding raw material liquid and dehydrating the water in the papermaking component. Molding mechanism, and an apparatus for producing a sheet-formed article having a dry-forming mechanism for pressing and drying a water-containing sheet-formed article, wherein a through-hole is provided in a press surface of a press die constituting the dry-forming mechanism, A discharge passage is formed by fitting a member having a plurality of discharge holes into the through hole.

[0008] Further, the method for producing a paper-formed article of the present invention comprises:
A papermaking component is extracted from the papermaking molding raw material liquid, a papermaking molding process is performed to obtain a hydrated papermaking molded product by dehydrating water in the papermaking component, and then a drying molding process of pressing and drying the hydrated papermaking molded product is performed. A method for producing a paper-molded article by performing, in the drying and forming step, using a press die having a discharge path formed by fitting a member having a plurality of discharge holes formed on a press surface, and into the press die. The hydrated paper-made molded product is sandwiched, and the molded product is pressed and dried while depressurizing the inside of the mold from a discharge path.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. The manufacturing apparatus of the present invention has a paper making mechanism and a dry forming mechanism. FIG. 1 shows an example of a paper making mechanism constituting the present invention apparatus, and FIG. 2 shows a dry forming mechanism constituting the present invention apparatus. An example is shown. In the drawings, reference numeral 1 denotes a paper making mechanism, and reference numeral 6 denotes a dry forming mechanism.

The papermaking and forming mechanism 1 includes, for example, an upper mold 3 having an inner surface shape or an outer surface shape of a container to be made as shown in FIG. 1 (in the example shown in the figure, a shape substantially matching the outer surface shape of the container). Formed) and a papermaking lower mold 2 having the outer surface shape or inner surface shape of the container to be made (in the example shown in the figure, the lower shape 2 is formed in a shape substantially matching the inner surface shape of the container). And a support frame 4 for supporting the papermaking lower mold 2. When the papermaking lower mold 2 and the upper mold 3 are combined, a papermaking molding space is formed between them. In addition, 5 in FIG. 1 is a hole for drainage.

The upper die 3 of the paper making mechanism 1 is provided with a large number of fine holes through which air and water vapor can pass, and the material is preferably a metal or an elastic material. Examples of the metal include aluminum and nickel, and examples of the elastic material include rubber, elastic synthetic resin, and synthetic resin foam.

Although not shown, a plurality of small through holes are provided in the wall surface, upper surface, and the like of the papermaking lower mold 2.
The small through-holes are used for transmitting moisture in the raw material liquid for paper-making molding described below, and are usually of a diameter in order to allow moisture to efficiently pass therethrough and to prevent the papermaking component from passing therethrough. Is preferably a hole of 0.5 mm to 2.0 mm. If the pores are too large, the amount of papermaking components passing through the holes will increase, which will hinder papermaking at the location, or the papermaking components will penetrate into the pores, resulting in traces of pores in the resulting molded article. There is a possibility that the film will remain clearly and deteriorate the appearance. On the other hand, if the holes are too fine, clogging of the small through-holes is likely to occur, which may hinder the permeation of moisture.

Further, the papermaking molding lower mold 2 is provided with a vacuum pump or the like as required below the lower mold 2, and is evacuated to reduce the pressure on the lower surface of the lower mold 2 so that the papermaking molding material liquid can be reduced. It is good also as composition which sucks and dehydrates water.

The apparatus of the present invention has a drying and forming mechanism 6 in addition to the above-described paper making and forming mechanism 1. The dry forming mechanism 6 includes:
For example, as shown in FIG. 2, the upper press die 7a having the inner surface shape or the outer surface shape of the formed paper product (in the example shown in the figure, the upper die 7a is formed to have a shape substantially matching the outer surface shape of the formed product).
And a lower press die 7b having an outer surface shape or an inner surface shape of the molded article (in the example shown in the figure, formed into a shape substantially matching the inner surface shape of the molded product). When the mold 7a and the press lower mold 7b are combined, a dry molding space is formed between them. The press mold 7 is constituted by a pair of male and female press dies 7, and the press dies 7 are hydrated sheet-formed articles described below. 10 has means for drying. Further, the dry forming mechanism 6 may be configured so that the pressure on the lower surface of the lower mold 7b and / or the upper surface of the upper mold 7a can be reduced as necessary.

As the drying means provided in the press mold 7, an electric heating device is provided in the press mold 7 for heating and drying, or a high frequency oscillator is connected to the press mold 7 and high frequency (including microwave) is applied by the high frequency oscillator. And drying. In addition, drying by heating and drying by applying a high frequency wave can be used in combination.

As shown in FIG. 2, a plurality of through holes are formed in the press die 7a. A core vent 9 is fitted into the through hole, and a discharge passage 8 is formed. The core vent 9 is formed, for example, in a cap shape such as a cylindrical shape or a rectangular tube shape as shown in FIG. A discharge hole 9b formed of a slit is provided.

The core vent 9 can usually be formed from a material such as aluminum, and has a size of 0.5 c in diameter.
It is preferably about m to 2 cm. Further, when the discharge holes 9b provided in the core vent 9 are fine holes, it is preferable to provide fine holes having a diameter of about 0.1 mm to 1.5 mm at a rate of 3 to ²⁰⁰ per 1 cm ^2. 9b
Is a slit, it is preferable to provide slits having a width of about 0.1 mm to 1.5 mm at intervals of 0.5 mm to 2 mm. Further, it is preferable to provide the core vent 9 in the press die 7 so that the ratio of the area of the discharge hole 9b to the surface area of the press surface of the press die 7 is 0.3 or less.

In the present invention, it is important that such a core vent 9 is provided in the press die 7 constituting the dry forming mechanism 6. By providing the core vent 9 having the discharge holes 9b on the entire surface 9a in the press die 7 as described above, the papermaking components are blocked by the core vent 9 when the hydrated papermaking molded article 10 is dried under reduced pressure. Can be prevented from invading. Moreover, even if the discharge hole 9b provided in the core vent 9 is small enough to prevent the intrusion of papermaking components, the inside of the dry molding space formed when the upper press die 7a and the lower press die 7b are mated. Moisture and water vapor can be efficiently removed from the hydrated papermaking molded article 10 that has been pressed. As described above, the core vent 9 is preferably provided in the press die 7, that is, both the press upper die 7a and the lower die 7b, but may be provided in only one of the press upper die 7a and the lower die 7b. Further, the core vent 9 whose discharge hole 9b is a fine hole and the core vent 9 which is a slit may be provided in the press die 7 in a unified manner, or may be provided as a mixture.

Next, the method of the present invention for producing a paper-molded article using the above-described production apparatus will be described. According to the method of the present invention, a papermaking molding intermediate 10 is first formed by extracting papermaking components from a papermaking molding raw material liquid (papermaking molding step), and then the papermaking molding intermediate 10 is dried and formed (drying). Molding step) A papermaking molded article is manufactured.

As the papermaking molding raw material liquid, a conventionally known pulp raw material liquid in which pulp is dispersed, and various additives such as a water-soluble polymer and a thermoplastic resin or a fiber which is melted by heat at the time of pressing are added thereto. Things etc. are used. In the papermaking molding raw material liquid, there is no problem even if the recycled pulp raw material using the recovered paper occupies all the components or occupies only a part thereof.

The papermaking molding step of making papermaking components from the papermaking raw material liquid is performed in the papermaking molding mechanism 1 described above. In the papermaking molding step, for example, the papermaking molding raw material liquid is poured onto the papermaking molding lower mold 2 to form the papermaking components on the lower mold, or the entire lower mold 2 is immersed in the papermaking molding liquid tank. If necessary, vacuum suction is performed from below the lower mold 2, and then the lower mold 2 is raised to remove the papermaking components in the papermaking raw material liquid from the lower mold 2.
The papermaking component in the papermaking raw material liquid is taken out on the papermaking lower mold 2 by, for example, papering. Next, the upper mold 3 and the lower mold 2 are combined to form a papermaking molding space, and the papermaking components are pressed. Further, if necessary, vacuum suction or / and / or
Then, air pressure is applied from the upper surface side of the upper mold 3. As a result, most of the water remaining in the papermaking components collected on the lower mold 2 flows out of the support frame 4 through the small holes of the lower mold 2, and the moisture is discharged onto the lower mold 2. The contained papermaking components are removed and left to form the hydrated papermaking molded article 10 having the shape of the lower mold 2.

As described above, when the papermaking component is made into the papermaking lower mold 2, the amount of the papermaking component that is made on the lower mold 2 is:
It can be adjusted by the concentration of the papermaking components dispersed in the pulp raw material and the vacuum suction time performed as needed when making the lower mold 2.

As described above, the papermaking components in the papermaking raw material liquid are taken out on the papermaking lower mold 2, pressed from the upper side by the upper mold 3, and the lower side of the lower mold 2 is depressurized if necessary. Then, when the water is dehydrated, the water-containing molded article 10 having a predetermined shape obtained as described above has a water content of about 30% by weight to 70% by weight. The pressing by the upper mold 3 is 10 when the apparent thickness of the papermaking component on the lower mold 2 is 100.
Preferably, the pressure is reduced to about 40 to about 40 mm. When the pressure on the lower surface side of the lower mold 2 is reduced as necessary, the pressure reduction condition is preferably about 700 mmHg to 10 mmHg.

Next, the hydrated papermaking molded article 10 obtained as described above is transferred to a dry molding step to perform dry molding.
The drying and molding step is performed by the drying and molding mechanism 6 including the press mold 7 provided with the core vent 9 described above, and the hydrated papermaking molded article 10 is placed between the press mold 7 including the upper press mold 8 and the lower press mold 9. Is pressed in the dry molding space formed in the above, and is dried under reduced pressure while pressing the water-containing molded article 10 by applying heat and / or high frequency to obtain a molded article. According to the method of the present invention in which the drying step is performed by the press die 7 provided with the core vent 9, the press die 7
The moisture remaining in the hydrated molded article 10 and the water vapor generated by evaporation from the hydrated molded article 10 are efficiently removed from the dry molding space without the papermaking component entering the discharge path 8 by the core vent 9 provided in the outside. The drying efficiency can be improved.

In the above-mentioned dry molding step, the pressure in the dry molding space is reduced to 700 mmHg to 10 mmHg, and the pressure is reduced to 1 kg / cm ² · G-
It is preferable to press the hydrated paper-molded article with a pressing force of 10 kg / cm ² · G and a press time of about 3 seconds to 100 seconds. When the apparent thickness of the state is set to 100, it is preferable to dry-mold the powder so that the thickness is about 5 to 30. Further, in the case of heating and drying, the heating temperature is 50 ° C. to 400 ° C., and in the case of drying the papermaking intermediate product 10 by applying a high frequency, 10 ³ Hz to 10 ¹³ Hz, preferably 10 ³ Hz. ⁶
Hz to 10 ¹² Hz, more preferably 10 ⁷ Hz to 10 ⁸
A high frequency having an oscillation frequency of 1 Hz and an output of about 1 kW to 100 kW is applied. The drying by heating and the drying by application of high frequency may be performed independently, or both may be used in combination for more efficient drying.

[0026]

As described above, according to the apparatus for manufacturing a paper-molded article of the present invention and the manufacturing method of the present invention using the apparatus, the discharge path of the press die constituting the dry forming mechanism is provided with a plurality of discharge holes. Since the member formed with is formed by being fitted into the through hole provided in the press die, water and water vapor can be satisfactorily discharged in the drying and molding step, and the time required for drying the molded article can be reduced. Furthermore, since the papermaking component is prevented from entering the inside of the press mold by the member provided with the discharge hole having a small area, the labor for cleaning the inside of the press mold without the papermaking component sticking inside the press mold is reduced. Break. Further, even if the discharge holes of the discharge path forming member are clogged and the discharge efficiency is reduced, the same discharge effect can be obtained simply by replacing the member.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of a papermaking and forming mechanism constituting a device of the present invention.

FIG. 2 is a cross-sectional view showing an example of a dry forming mechanism constituting the apparatus of the present invention.

FIG. 3 is a perspective view showing an example of a member having a plurality of discharge holes to be fitted into a press die of a dry forming machine constituting the apparatus of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 papermaking molding mechanism 6 drying molding mechanism 7 press die 8 discharge path 9 core vent 9b discharge hole 10 hydrated papermaking molded article

Claims (2)

(57) [Claims] 1. A papermaking molding mechanism for extracting a papermaking component from a raw material liquid for papermaking, dehydrating water in the papermaking component to obtain a hydrated papermaking molded product, and pressing and drying the hydrated papermaking molded product. An apparatus for manufacturing a sheet-formed molded article having a dry forming mechanism, wherein a through hole is provided in a press surface of a press die constituting the dry forming mechanism, and a member having a plurality of discharge holes formed in the through hole is fitted into a discharge path. An apparatus for manufacturing a paper-molded article, comprising: 2. A papermaking molding step of extracting a papermaking component from a raw material solution for papermaking, dehydrating water in the papermaking component to obtain a hydrated papermaking molded product, and then pressing and drying the hydrated papermaking molded product. A method for producing a sheet-shaped molded article by performing a dry forming step to perform a dry forming step, wherein in the dry forming step, using a press die in which a member having a plurality of discharge holes formed on a press surface and a discharge path is formed, A method for producing a paper-molded article, comprising sandwiching a water-containing paper-molded article in the press mold, and pressing and drying the molded article while depressurizing the inside of the mold from a discharge path.