JPH05239789A - Production of crepe paper - Google Patents

Abstract

PURPOSE:To readily and stably obtain the subject paper having high wet elongation by placing a doctor on a press roll in a wet part and creping wet paper having a specific water content so as to make the paper have specific free run distance and wet elongation. CONSTITUTION:In subjecting pulp to papermaking, a doctor is placed on a press roll in a wet part and creping wet sheet, the wet sheet stuck fast to the press roll is released by the doctor and crepe is formed at 60-75wt.% water content of sheet. The free run distance of the sheet to reach the next paper roll is made to be 5-60cm, wet elongation is controlled in 10-35% and the sheet is wound on a reel to give the objective crepe paper having high and stable wet elongation. The free run of the wet sheet after creping is traveled by an inclined wire and preferably dried by a through-dryer.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing a crepe.

[0002]

2. Description of the Related Art Conventionally, as one of the easiest and most effective methods for imparting flexibility to paper, there is a method of creping the paper into so-called crepe paper.

Generally, creping of paper is performed in a papermaking process, and is creped at a doctor installed on a press roll in the wet part or on a cylinder type dryer in the dryer part. More specifically, the sheet adhered to the roll or cylinder type dryer is peeled off at the doctor.

This sheet is wound on a reel, and the rate of crepe is higher as the speed of the roll or cylinder type dryer / reel speed is increased by providing a speed difference between the roll or cylinder type dryer and the reel. It becomes larger, and the flexibility and elongation of the paper are increased.

As described above, there are cases where the wet part is creped and cases where the dry part is creped. The former is distinguished from the wet crepe and the latter is distinguished from the dry crepe.

The key points for producing crepe paper are to improve the adhesion of the sheet to a roll or cylinder type dryer, to minimize the sheet tension after creping, and the speed of the roll or cylinder type dryer. / For example, the value of the reel speed may be increased.

Compared to wet crepes, dry crepes are more common, but this is because a stable crepe with less paper moisture during creping can be obtained.
The tension of the paper can be smaller than that of the wet crepe, so that the creping rate can be increased.

[0008] In the case of wet crepe, since the water content during creping is large, the sheet may not be creped properly depending on the water content. In addition, since there is a drying process in the latter stage, the distance to the reel is long and the tension becomes large.

Further, as for the drying dryer in the latter stage, since the crepe is crushed by the usual multi-cylinder type Yankee dryer, the model of the dryer is restricted.

On the other hand, as an advantage of the wet crepe,
It maintains the shape of the crepe even when it is wet, has a large paper elongation and is flexible, and is very effective when applied to paper towels, paper towels and the like that use paper in a wet state. However, because of the aforementioned difficulties, it is currently difficult to obtain suitable conditions.

[0011]

As a result of various studies on the production conditions of wet crepes, the present inventor has found that the wet elongation is high by specifying the sheet moisture during creping and the distance of free run after creping. It has been found that crepe paper can be obtained easily and stably.

[0012]

DISCLOSURE OF THE INVENTION In the process of creping a wet sheet by applying a doctor on a press roll of a wet part, the present invention provides a free run after forming a crepe with a sheet water content of 60 to 75% by weight. Distance of 5 ~
This is a method for producing crepe paper having a wet elongation of 10 to 35% at 60 cm.

[0013]

The sheet moisture in the present invention is 60 to 75% by weight, preferably 65 to 70% by weight. If the water content of the sheet is less than 60% by weight, the adhesion to the press roll is insufficient and the crepe flies off and cannot be cleaned properly. On the other hand, when the water content exceeds 75% by weight, sheet formation is not sufficient and it becomes difficult to crepe.

The free run in the present invention is the traveling distance of the sheet until the next paper roll after the crepe is formed, and the shorter the free run, the better. In other words, if the free run is longer than 60 cm, the seat will sag, and the tension of the seat must be increased in order to eliminate this sagging, and the crepe rate will decrease. On the other hand, a free run
It is difficult to reduce the height to 5 cm or less in terms of operability and equipment.

The wet elongation in the present invention is measured by JIS after immersing in water at 20 ° C. for 10 minutes and then removing the water adhering to the surface of the paper piece with absorbent paper.
The wet elongation is 10-35, measured according to 8132.
Must be in the range of%. If the wet elongation is less than 10%, the flexibility of the crepe paper when wet is insufficient. On the other hand, if the wet elongation exceeds 35%, it is too soft and the crepe paper loses its elasticity.

As described above, wet crepe paper is characterized in that it has a large elongation when wet, which is an advantage that cannot be obtained with a dry crepe in which the crepe disappears when wet.

[0017]

Examples 1 and 2 The present invention will be specifically described below with reference to Examples, but the present invention is of course not limited thereto.

A crepe paper having a basis weight of 60 g / m ² was made by a combination of the mixing ratio of the raw materials shown in Table 1, the chemical addition ratio, the sheet moisture at the time of creping, the free run inclined wire and the through dryer.

[0019]

[Comparative Examples 1 and 2] Under the conditions shown in Table 1 and free running
One having a size of 150 cm was used as Comparative Example 1, one having a sheet moisture of 55% by weight when creped was used as Comparative Example 2, and Example 1 was used.
Table 2 shows the results of measuring the tensile strength, elongation (air dry, wet), stiffness, etc. of these crepe papers in the same manner as in No. 2 to No. 2.

[0020]

[Table 1]

[0021]

[Table 2]

As can be seen from Table 2, a stable crepe with high wet elongation can be obtained by defining the sheet moisture and free run during creping.

[0023]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, in producing wet crepe paper, by forming the crepe with the sheet moisture of 60 to 75% by weight, the free run distance is set to 5 to 60%.
By setting it to be cm, it is possible to produce a crepe paper having a high and stable wet elongation.

Claims (1)

[Claims] 1. In the step of creping a wet sheet by applying a doctor on the press roll of the wet part, the free run distance after forming the crepe with the sheet moisture of 60 to 75% by weight is 5 to 60 cm. Wet elongation at 10 to
A method for producing crepe paper, characterized in that the content is 35%.