JPH0433920B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for easily and continuously imparting an uneven pattern to the surface of a soft board made of vegetable or mineral material without reducing the strength of the fiber itself.

Generally, the purpose of imparting an uneven pattern to the surface of a soft fiberboard is to improve the cosmetic properties or sound absorption properties of the fiberboard.There are various methods for this, and a wide variety of questions have been asked. ing.

In the original invention, without applying any special treatment to the surface of the wet mat, by pressing it with a sheet-like material to form an embossed pattern and dewatering it at the same time, a clear embossed pattern can be formed while suppressing the strength loss of the fiberboard. However, once the wet pine is dehydrated and made into paper, the entire pine constitutes a porous elastic body due to the intertwining of the fibers, so it is possible to improve productivity by creating an uneven pattern with a short press. Then, the following problem occurred.

(1) There is a large springback immediately after molding, and the pattern does not appear sharp and the fine uneven pattern disappears.

(2) It is necessary to press for a long time to stabilize the uneven pattern, and the embossing process takes a long time, resulting in a lack of productivity.

(3) Since the wet mat has appropriate elasticity due to the entanglement of fibers, when it is pressed and embossed on the cylinder of a circular mesh paper machine, a load is applied to the paper mesh in the cylinder, and the load is concentrated by linear pressure as in roll embossing. Embossing methods that apply pressure may damage the paper mesh.

There is also a method, as shown in Japanese Patent Application Laid-open No. 48-97923, in which only the surface portion of a fiberboard that has been dried into a plate is moistened with moisture, and then an uneven pattern is formed using a roll or the like. However, in this case, since the pressure is only applied in a wet state, even if an uneven pattern is applied, the spring bugs are large and the pattern easily collapses, and it is difficult to create a deep uneven pattern, and it is difficult to use paper-made nets. It will hurt you.

In addition, in this method, in order to form an uneven pattern on the fibrous material that is once dried and made into a plate, it is necessary to dry the sheet after drying it, and then dry it after adding water to form the uneven pattern. Since this requires a drying process, the amount of energy required for the drying process increases, which is uneconomical, and there is also the problem that efficient production cannot be achieved with a short production line.
The present invention was made to solve the various problems mentioned above, and involves spraying water or an aqueous solution such as resin on the surface of the mat in a wet state immediately after papermaking to weaken the entanglement of fibers on the surface layer of the mat. The present invention provides a method for manufacturing a soft fiberboard, which is characterized in that the fibers are preferably placed in a suspended state to form an uneven pattern and, at the same time, water is sucked and dehydrated from the back surface of the mat.

Next, an embodiment of the present invention will be described based on drawings using a circular mesh paper making machine.

The circular mesh papermaking machine is composed of a cylinder 1, a butt 2 disposed along the lower part of the cylinder 1, and one or more press rollers 3 disposed along the upper circumferential surface of the cylinder 1. There is. 4
is a slurry containing 0.5 to 3.0% of vegetable fiber or mineral fiber that is supplied to the vat of this papermaking machine, and is connected to and communicated with the cylinder 1 by a pressure reducing device (not shown).
Due to this action, the fibers adhere to the surface of the cylinder 1, and are lifted up from the vat 2 by the rotation of the cylinder 1, forming a wet mat 5. 6
is a sheet-like material such as a rubber or fibrous sheet, a mesh or other perforated sheet stretched endlessly between the press rollers 3 on the cylinder 1, and has an uneven pattern on its surface. It is pressed by the press roll 3 and dehydrated at the same time as patterning. However, the moisture content of wet matte 5 extracted by cylinder 1 is 150% on a dry basis.
Since the water from the front and back is dehydrated by the reduced pressure in the cylinder, at this level of moisture content, the fibers of the wet mat 5 are relatively entangled, and even if pressed in this state, there will be a large spring back. In order to create a large and clear uneven pattern, it is difficult to press the spring back with great force and for a long time, otherwise the pattern will disappear.

Therefore, in the present invention, water or an aqueous solution of diluted synthetic resin is supplied from a spray nozzle 7 disposed close to the paper-made wet mat 5 to improve the moisture content of the surface of the wet mat 5, and After forming a surface layer in which the fibers are disentangled and are highly plastically deformable, the sheet is sent to a sheet-like material 6 to form an uneven pattern on the surface layer. In this case, when water or the like is pressurized by spraying or the like, the fibers are easily untangled and the pattern is more easily formed. Reference numeral 8 denotes a brush roll disposed close to the wet mat 5 in front of the spray nozzle 7, which scrapes off excess slurry 4 scooped up from the vat 2 to form a wet mat of uniform thickness. It is. The wet pine 5 is sent to the sheet-like material 6 in a floating state in which the fibers on the surface layer are disentangled by the water jetted from the spray nozzle 7 and the fibers are suspended in a large amount of moisture. , 3, the mat is pressed by a sheet material 6 having an uneven pattern, and the surface layer of the mat is easily plastically deformed, and a clear uneven pattern is formed in a short time. Since the suction force is applied to remove water, the excess water applied to the wet mat is removed by dehydration, and the pattern applied to the mat 5 does not disappear after the pressure from the press roll 3 is released.

In addition, the surface layer of the wet pine is sprayed with a spray nozzle 7.
The water jet disentangles the fibers and puts them in a floating state, so even when pressed with the press roll 3 and sheet material on the cylinder 1, almost no pressure is applied to the paper mesh in the cylinder 1, and the surface layer of the pine is removed. The cylinder 1 can be plastically deformed, patterns can be applied on the cylinder 1 without the risk of damaging the papermaking net, and the process can be carried out on a short production line.

In this state, the moisture content of the wet mat 5 is high, so the moisture content is reduced by about 10% using a suitable device such as a roll press, and then dried.

In the above embodiments, the sheet material 6 having an uneven pattern was passed over the press rolls 3 to form the uneven pattern, but the sheet material 6 was not used and the press roll 3 was replaced with an embossing roll. Even if an embossing roll is used, the fibers in the surface layer of the wet mat are disentangled by the water jetted from the spray nozzle 7, and the cylinder 1 is plastically deformed with almost no elasticity. There is almost no load applied to the paper-made net by pressing, and there is no risk of damaging the paper-made net.

Note that water or hot water can be used as the solution sprayed onto the wet mat, but synthetic resin or coloring agents may be mixed into this to strengthen or color the fiberboard surface after molding. Properties can also be given.

As described above, the present invention further supplies water or an aqueous solution such as a resin to the wet surface of pine obtained by paper-making a slurry containing vegetable or mineral fibers, thereby removing the fibers in the surface layer of the pine. After weakening the entanglements, press a belt, net-like material, or roll having an uneven pattern on the pine surface to give the pine surface an uneven pattern, and at the same time, suck and dehydrate the moisture seeping from the back surface of the wet pine, and then dry it. This method relates to a method for manufacturing a soft fiberboard having an uneven pattern characterized by the following: By further supplying water or an aqueous solution such as a resin to the wet mat, the fibers on the surface layer of the mat are not only kept in a wet state. , the fibers are placed in a floating state in which they are disentangled and then pressed to give an uneven pattern, so the plastic deformation of the fibers is easily carried out and a clear pattern can be obtained even with short pressing. Excess water is quickly sucked and dehydrated from the back side of the wet mat, which eliminates the collapse of the uneven pattern shape and creates a sharp pattern. Further, even if the wet mat is pressed with a press roll or a sheet-like material, almost no pressure is applied to the paper mesh of the cylinder, so the paper mesh is not damaged. Furthermore, even after the pressing force during deformation is released, there is almost no spring baggage in the patterned part, and the surface of the fiberboard is less prone to cracking, making it possible to efficiently produce soft fiberboard with high commercial value on a short production line. It is effective.

4 Additional relationship Original patent No. 1207165 (Special Publication No. 58-37152)
The invention of No. 1) is configured to press a sheet or a net-like material having an uneven pattern on the wet surface of the mat immediately after papermaking to impart an uneven pattern to the surface of the mat, and at the same time to suck and dehydrate the moisture exuding from the mat. Although this is the main part, this invention also has a structure in which a belt, a net-like material, or a roll having an uneven pattern is applied to the surface of the mat in a wet state to impart an uneven pattern to the surface of the mat, and at the same time, suction and dehydration are carried out from the back surface of the mat. It also achieves the same purpose as the original patented invention in that it suppresses the decrease in strength of the fiberboard and provides a good embossed pattern, and is stipulated in Article 31, Item 1 of the Patent Law. Applicable.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is an explanatory view of the manufacturing method, and FIG. 2 is a perspective view of a fiberboard obtained using a reticulated sheet. 4... Slurry, 5... Wet mat, 6... Sheet-like material, 7... Spray nozzle.

Claims (1)

[Claims] 1. On the surface of wet pine obtained by paper-making a slurry containing vegetable or mineral fibers,
Furthermore, after water or an aqueous solution such as a resin is supplied to weaken the entanglement of the fibers on the surface layer of the pine, a belt, a net-like material, or a roll having an uneven pattern on the surface of the pine is pressed to impart an uneven pattern on the surface of the pine. A method for producing a soft fiberboard having an uneven pattern, which comprises sucking and dehydrating water seeping from the back surface of a wet mat, and then drying the material. 2. The method for manufacturing a soft fiberboard having an uneven pattern according to claim 1, wherein the water or aqueous solution supplied to the mat surface is pressurized.