JPS5927438B2 - Method for manufacturing filter paper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing two pieces of paper in which a low-density part and a high-density part are arranged in parallel and integrally formed.

BACKGROUND ART Conventionally, in order to extend the life of a filter such as an oil filter for an internal combustion engine, it has been known to impart a dense structure to two papers constituting the filter.

Two papers of this kind are proposed, such as those described in Utility Model Publication No. 50-43801, in which transparent parts (coarse density) are partially formed integrally with a sawn material of constant density (dense density). Been ℃・ru.

The method of manufacturing this P paper is to change the mesh degree of the paper-making wire mesh of a general paper machine in order to give the paper-making raw material a difference in water drainage, or to use a metal plate or plastic material for the paper-making wire mesh of a general paper machine. By pasting a film, a large amount of fiber layer is collected in the part of the wire mesh for paper making that drains well to form a dense part, and a small amount of fiber layer is collected in the part that does not drain well to form a part of coarse density. There are known ways to configure the .

However, the conventional method described above requires extensive modification of the well-known paper machine so that the paper wire mesh can be replaced as necessary, and the metal plate and plastic film attached to the paper wire mesh peel off during use. However, if the mesh degree of the wire mesh for paper making is changed, the fine mesh areas may become clogged in a short period of time, making it difficult to stably produce two papers of the same quality. There is.

In order to solve the above-mentioned drawbacks, the present invention replaces the conventional method of imparting a difference in water drainage of papermaking raw materials in a wire mesh for papermaking.
A new method is adopted in which a water-impermeable sheet has a number of triangularly pointed protrusions arranged in parallel with a predetermined gap between them, and the protrusions of the sheet change the flow of papermaking raw materials. By doing this, it is possible to integrally form a dense part and a coarse density part in a parallel state without applying various tricks to the wire mesh for paper making as in the past, and therefore, various tricks can be applied to the wire mesh for paper making. The purpose of this invention is to eliminate the above-mentioned drawbacks caused by applying this method, and also to be able to manufacture it at a low cost.

The present invention will be explained below with reference to the drawings.

First, a paper machine for carrying out the present invention is shown in Figs. 1 and 2.
This will be explained with reference to the diagram.

1 is a head box for accommodating suspended papermaking raw materials in which natural fibers and/or synthetic fibers are dispersed in water.

2 is a rotating drum, and 3 is a roller.

Reference numeral 4 denotes a wire mesh for paper making that is rotated and moved by the rotating drum 2, and is generally called a fourdrinier.

A sheet 5 has a thickness of, for example, about 1.0 mm and is made of a water-impermeable material such as plastic, rubber, or wood.

This sheet 5 is constructed by integrating a plurality of protrusions 5b having a rectangular shape and having triangular pointed tips 5a arranged in parallel with a gap (5c), and has a comb-like shape. .

Note that the protrusions 5b can also be integrated by coupling them to each other.

This sheet 5 is submerged in the papermaking raw material and placed parallel to the papermaking wire mesh 4, and is fixed regardless of the movement of the papermaking wire mesh 4 (in the direction of arrow C).

Next, the manufacturing method of the present invention using the above-mentioned paper machine will be explained in detail with reference to FIGS. 1 and 3.

Note that the tip angle R of the protrusions 5b of the sheet 5 was 90°, the width was 10 mrn, and the length was 200 m, and the width of the notch 5c between the protrusions 5b was 10 mm.

In addition, as a papermaking raw material, Kotton Linter Pulp 50
~70% by weight, 3-7 denier papermaking lacon 5
A papermaking raw material in the form of a suspension in which 0 to 30% of heavy weight was mixed in water was used.

The papermaking raw material flows in the direction of arrow A because water is drained by gravity falling through the mesh of papermaking wire mesh 4 (arrow B).

When the papermaking raw material flows in this way and reaches the moving papermaking wire mesh 4, since the sheet 5 is disposed above the papermaking wire mesh 4, the sheet 5 protrudes from the sheet 5. The papermaking raw material on the portion 5b is not drained, but the papermaking raw material is drained only at the notch 5C of the sheet 5 (in the direction of arrow B), so that the papermaking raw material on the protruding portion 5b of the sheet 5 is partially drained. It is attracted to the notch 5c.

Therefore, a band-like fiber layer is formed in the paper-making wire mesh 4 at the notch portion 5c of the sheet 5, and this band-like fiber layer advances in the direction of arrow C as the paper-making wire mesh 4 advances.

Then, at a position beyond the tip 5a of the protruding part 5b of the sheet 5, the water-draining action that was blocked by the protruding part 5b is now subjected to the water-draining action, so another band-like fiber layer is formed between the above-mentioned band-like fiber layers. will be done.

This band-shaped fiber layer is formed of the papermaking raw material whose water-draining action is blocked by the protrusion 5b of the sheet 5, but as described above, the papermaking raw material on the protrusion 5b of the sheet 5 is attracted to the notch 5c and the fibers are Since the concentration is low, the amount of fibers in the band-like fiber layer formed on the paper-making wire mesh 4 is relatively small, and the band-like fiber layer is coarse in terms of density.

On the other hand, in the notch 5c between the protrusions 5b of the sheet 5, the water draining action is performed one stage earlier, and this notch 5c
The amount of fibers in the band-like fiber layer formed on the papermaking wire mesh 4 at the part is larger than that of the previous band-like fiber layer, and the band-like fiber layer is dense in terms of density.

In the above-mentioned papermaking stage, when the papermaking raw material reaches the sheet 5 portion and is drained at the notch 5° portion of the sheet 1-5, the tip 5a of the protruding portion 5b of the sheet 5
turbulence may occur in the flow of papermaking raw materials.

When turbulence occurs in this way, the papermaking raw material that undergoes the draining action at a position beyond the tip 5a of the protruding portion 5b of the sheet 5 is affected, and as a result, the tip 5 of the protruding portion 5b of the sheet 5
The density of the band-like fiber layer formed by the draining action becomes uneven at a position exceeding a, and it becomes impossible to form a coarse band-like fiber layer with uniform density.

However, in the present invention, since the tip 5a of the protruding portion 5b of the sheet 5 is sharpened in a triangular shape, the papermaking raw material flows along the sharpened tip 5a, so that turbulence occurs in the flow of the papermaking raw material at the tip 5a. It rarely occurs.

Note that the angle R (Fig. 2) of this tip 5a is 60° to 12°.
0° is preferred.

Further, the tip 5a preferably has an isosceles triangular shape.

Thus, according to the present invention, by employing the sheet 5, in the sheet 5 portion, a large amount of papermaking raw material flows into the notch portion 5c between the protruding portions 5b of the sheet 5, and a large amount of fiber is deposited.
Further, at a position beyond the protrusion 5b of the sheet 5, a notch 5 is formed.
Compared to case c, the flow of papermaking raw material is smaller and a small amount of fiber (compared to other years) is deposited, so that the dense band-like fiber layer and the coarse-density band-like fiber layer are regularly aligned and integrated. You will get an array of paper sheets.

This piece of paper is pressed between rolls maintained at a predetermined temperature.

A paper according to the invention is shown in FIG.

In this FIG. 4, 6a is a high-density portion, and 6b is a low-density portion.

In the baffle body using R paper with this structure, the flow velocity is high in the low-density part 6b, and the flow velocity is low in the dense part 6a, resulting in a high f-slowing efficiency, resulting in a high flow efficiency as a whole. is obtained.

In addition, as the period of use of the single-layer body becomes longer, the denser part 6a first becomes clogged, the pressure loss gradually increases, and the flow rate to the less dense part 6b increases, causing the overflow. The life of the baffle body is extended because the pressure loss increases slowly without loss of efficiency.

Incidentally, even in the coarse-density portion 6b, large particles that would damage important parts of the internal combustion engine can be sufficiently removed.

FIG. 5 shows another embodiment of the present invention, and this embodiment will be explained.

In this embodiment, the tip 5a of the sheet 5 similar to that shown in FIG.
Only the protruding portion 5b of the sheet 5 is immersed into the papermaking raw material so as to be immersed.

When papermaking raw materials are supplied to the head box 1 and paper is made, the flow of the papermaking raw materials is not obstructed at the notch 5c of the sheet 5, and the portion of the papermaking wire mesh 4 corresponding to the notch 5c In this process, a large amount of papermaking raw material is drained.

On the other hand, the flow of the papermaking raw material is blocked at the protrusion 5b of the sheet 5, and a small amount of papermaking raw material is drained at a portion of the papermaking wire mesh 4 corresponding to the protrusion 5b.

As a result, a dense band-like fiber layer is formed in the portion of the sheet 5 corresponding to the notch 5c, and the protruding portion 5 of the sheet 5
A band-like fiber layer with a coarse density is formed in the portion corresponding to b.

In this way, a laminated paper is obtained in which strip-shaped fiber layers of different densities are integrally arranged in regular juxtaposition.

In addition, since the tip 5a of the notch 5c of the sheet 5 is sharp, the papermaking raw material flowing through the notch 5c of the sheet 5 generates turbulence at the tip 5a, causing a turbulent flow at the protrusion 5b of the sheet 5.
A notch 5c is formed in a small amount of papermaking raw material flowing through a portion corresponding to
This prevents a large amount of the papermaking raw material flowing through the pipe and pulsating flow of the papermaking raw material.

Therefore, the band-shaped fiber layers having different densities are arranged regularly and alternately, and the density distribution of each fiber layer is uniform.

In this embodiment as well, the flow of the papermaking raw material is changed by the protruding portion 5b of the sheet 5, as in the above-described embodiment.

In addition, in the R paper shown in FIG. 4, the dense part 6a and the coarse density part 6b have the same thickness, but in order to make them the same thickness, the protrusion of the sheet 5 is necessary. The length dimension of the portion 5b, the width dimension of the cutout portion 5c of the sheet 5 (the protruding portion 5b
(dimensions between the two) etc.

Further, the intervals between the protrusions 5b of the sheet 5 do not have to be equal intervals, and the intervals may be changed arbitrarily.

Further, in one paper manufactured according to both of the above embodiments, a density gradient may also be provided in the thickness direction of the dense portion 6a and the coarse density portion 6b.

In addition, the present invention is not limited to a paper making method using a fourdrinier paper machine as in the above embodiments, but can also be applied to a paper making method using a circular wire paper machine having a roll-shaped wire mesh for paper making. Applicable.

As described in detail above, according to the present invention, a water-impermeable sheet in which a large number of protrusions having a rectangular shape and triangularly pointed tips are arranged in parallel with a gap is formed into a movable paper sheet. The sheet is placed on a wire mesh with the tip of the protrusion facing in the direction of movement, and while the paper wire mesh is moved in a predetermined direction, the papermaking raw material is poured onto the wire mesh, and the sheet is spread onto the paper wire mesh. By changing the flow of the flowing papermaking raw material, a large amount of papermaking raw material flows between the protruding parts of this sheet to form a dense band-like fiber layer between the protruding parts of this sheet in the papermaking wire mesh, and A smaller amount of papermaking raw material is poured into the areas corresponding to the protrusions of the sheet than between the protrusions of the sheet, and a band-like fiber layer with a coarse density is formed in the parts of the papermaking wire mesh that correspond to the protrusions of the sheet. However, since the paper is made so that strip-shaped fiber layers with different densities are arranged in parallel and integrated, it is possible to simply place the seal on the paper-making wire mesh without making various modifications to the paper-making wire mesh as in the past. Because dense parts and coarse parts can be integrated in parallel with each other by simply installing wire mesh for paper making, it is necessary to make extensive modifications to the paper machine by making various modifications to the wire mesh for paper making. It is possible to eliminate the temperature and corrosion defects that occur when the same quality of paper cannot be obtained due to peeling of the metal plate attached to the paper.

Furthermore, compared to the conventional method in which wire mesh for paper making is decorated, it is clear that paper can be produced at a lower cost.

Furthermore, in the present invention, since the tip of the protrusion of the sheet is pointed in a triangular shape, there is almost no turbulence in the papermaking raw material flowing near this tip, and density unevenness occurs in the band-shaped fiber layer of the pile paper. In most cases, uniform density is obtained in each band-shaped fiber layer of P paper, and the quality of one paper is stable.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a paper machine for explaining an embodiment of the manufacturing method of the present invention, FIG. 2 is a plan view showing a sheet used in the manufacturing method of the present invention, and FIG. 3 is a diagram of the manufacturing method of the present invention. , a schematic perspective view for explaining the draining action of the papermaking raw material on the wire mesh for papermaking, FIG. 4 is a sectional view showing the laminated paper produced by the production method of the present invention, and FIG. FIG. 3 is a schematic configuration diagram of a paper machine for explaining another embodiment of the method. 4... Wire mesh for paper making, 5... Sheet, 5
a...Tip, 5b...Protrusion, 5c...
...Notch portion, 6a... Dense part, 6b... Coarse density part.

Claims (1)

[Claims] 1 Above a movable wire mesh for papermaking, a water-impermeable sheet with a large number of strip-shaped protrusions with triangularly pointed tips arranged in parallel with gaps is placed. The wire mesh for paper making is arranged so as to face the moving direction of the wire mesh for paper making, and while the wire mesh for paper making is moved in a predetermined direction, a papermaking raw material made of a mixture of fibers and water is poured onto the wire mesh to cause the sheet to protrude. The flow of the papermaking raw material is varied depending on the part, so that more papermaking raw materials are allowed to flow into the portions of the papermaking wire mesh between the protrusions of the sheet, and the portions of the papermaking wire mesh corresponding to the protrusions of the sheet. A smaller amount of papermaking raw material flows between the protrusions than between the protrusions, and due to the change in the flow of papermaking raw materials, a dense band-like fiber layer of papermaking raw materials is formed in the portions of the papermaking wire mesh through which a large amount of papermaking raw materials flow. A band-like fiber layer with a coarse density is formed by the paper-making raw material in the portion of the paper-making wire mesh through which a small amount of paper-making raw material flows, and thus the band-like fiber layers of different densities are arranged in parallel in an integrated manner. 2. A method for producing paper, which is characterized by paper-making.