JP2886336B2 - Manufacturing method of glassine paper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is intended to prevent wear marks from remaining on the roll surface in contact with the side edges of glassine paper as surface steps even after continuous operation for a long period of time. The present invention relates to a method for producing high-quality glassine paper free from defects.

"Conventional technology" Conventionally, glassine paper is generally produced by making a paper stock made from highly beaten chemical pulp, then applying a suitable amount of water, supercalendering under high temperature and high pressure conditions. It is.

By the way, the super calender device uses a multi-stage type, and the pressure linear pressure is generally 100 to 250 kg / cm.However, since the elastic roll is soft and easily deformed, it actually comes into surface contact and a high linear pressure is obtained. I can't.

Since the elastic roll rotates while deforming under pressure, it generates self-heating, which requires a cooling device. Clear wear marks remain as surface steps on the roll surface in contact with the part, and the operation of the super calender device must be interrupted frequently for replacement and re-polishing of the roll, which increases the operating cost .

In addition, for example, it is necessary to transport a roll of paper manufactured by a paper machine to a separately provided super-calender device and perform a high smoothing process. Accordingly, a paper winding transport facility and a super calender device operating personnel are required.

Furthermore, a place for storing untreated windings is required, which is another reason why operating costs cannot be reduced.

[Problems to be Solved by the Invention] The present invention provides a high-quality, high-quality film in which wear marks do not remain as surface steps on the roll surface in contact with the side edge of glassine paper even when continuous operation is performed for a long period of time. It is intended to provide a production method for obtaining a natural glassine paper.

"Means for Solving the Problems" The present invention consists of two or more metal rolls, and at least one metal roll has a surface temperature of 80 to 200 ° C. This is a method for producing glassine paper, characterized in that a sheet is drawn under a pressurized condition and a high smoothing treatment is performed.

[Operation] The method for producing glassine paper of the present invention will be described in detail below.

The method for producing glassine paper of the present invention comprises a pressurizing condition of 100 kg / cm or more in a nip portion composed of two or more metal rolls and at least one metal roll heated to a surface temperature of 80 to 200 ° C. In this configuration, the sheet is pulled down below to perform a high smoothing process.

If the sheet is drawn through the nip where the metal roll is heated to a temperature range of 80 ° C or less at the surface temperature,
The effect of the present invention of making the sheet glassy cannot be sufficiently obtained.

On the other hand, if the sheet is drawn through the nip portion where the metal roll is heated to a temperature range of 200 ° C. or higher at the surface temperature, the sheet becomes excessively glycinized, and as a result, the mechanical strength of the sheet is reduced. It will be extremely short.

Further, when the sheet is drawn through the nip portion under a pressure condition of 100 kg / cm or less, both the Beck smoothness value and the Gurley air permeability value on both sides of the obtained sheet are insufficient.

As a specific example of forming the pair of metal rolls, at least one metal roll has a surface temperature of 80 to 200.
Apply linear pressure to the nip, which is heated to a temperature range of ℃.
Any device that can satisfy the pressurizing condition of 100 kg / cm or more can be appropriately adopted.

For example, a Magmatic power calender manufactured by Bellmatic Co., Ltd., a two-stage calender, a multi-stage calender, etc. may be mentioned.

Note that the configuration in which the nip portion made of a metal roll is provided between the drying step and the winding step of the paper machine eliminates the need to transport the winding of the paper manufactured by the paper machine to a separately provided device.

Accordingly, there is no need for a transporting apparatus for paper winding and an operation staff for the apparatus, and a place for storing and storing unprocessed winding is unnecessary, so that the operating cost can be reduced. This is one of preferred embodiments of the present invention.

"Examples" Hereinafter, the present invention will be described more specifically with reference to Examples, but it is needless to say that the present invention is not limited to these Examples. In addition, all% in an Example has shown the weight%.

(Example 1) Commercially available softwood bleached kraft pulp (hereinafter abbreviated as "NBKP") was beaten to 200 ml of CSF at a pulp concentration of 4% with a single disc refiner to obtain a beaten paper for preparation.

0.25% of rosin (weight ratio to pulp, the same applies hereinafter) and 3% of sulfuric acid band were sequentially added to this stock, and the sheet was passed through a papermaking machine at a speed of 200 m / min. Is dried to a moisture content of 15%. Immediately, the nip is heated to a surface temperature of 85 ° C or higher using a Velmatic Magna power calender made of two-stage metal rolls. A pressure line pressure of 105 kg / cm was passed through the portion to obtain glassine paper.

(Example 2) A glassine paper was obtained in the same manner as in Example 1 except that the surface temperature of the metal roll was changed to 105 ° C.

(Example 3) A glassine paper was obtained in the same manner as in Example 1 except that the surface temperature of the metal roll was changed to 180 ° C.

(Example 4) A glassine paper was obtained in the same manner as in Example 1 except that the pressure linear pressure was changed to 150 kg / cm.

(Example 5) A glassine paper was obtained in the same manner as in Example 1 except that the pressure linear pressure was changed to 200 kg / cm.

(Comparative Example 1) A glassine paper was obtained in the same manner as in Example 1 except that the surface temperature of the metal roll was changed to 28 ° C.

(Comparative Example 2) A glassine paper was obtained in the same manner as in Example 1, except that the pressure linear pressure was changed to 50 kg / cm.

(Comparative Example 3) A glassine paper was obtained in the same manner as in Example 1, except that the surface temperature of the metal roll was changed to 220 ° C.

The eight kinds of glassine papers thus obtained were subjected to a comparison test of Beck smoothness, Gurley air permeability, tightness and Hunter opacity on the front and back surfaces of the sheet.

 The results, including the comprehensive judgment, are shown in the attached table.

 The evaluation criteria for the comprehensive judgment are as follows.

1: Extremely good 2: Excellent 3: Normal 4: Slightly inferior 5: Poor ・ Gurley air permeability 気 Measured based on ASTM D-726.

・ Hunter opacity ‥‥ Value measured with a Hunter reflectometer based on JIS P8138. Note that the higher the numerical value, the higher the opacity, and conversely, the lower the numerical value, the better the transparency.

[Effect] Even if the metal roll used in the production method of the present invention is used continuously for a long period of time, the amount of wear of the roll surface is minimized as in the related art, and as a result, the side edge of the glassine paper is reduced. The amount of wear marks remaining as surface steps on the roll surface in contact with the part is extremely small.

Therefore, the frequency of interrupting the operation of the apparatus for changing or re-polishing the roll is minimized.

As is clear from the results in the table, high-quality glassine paper can be stably obtained over a long period of time.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-55-51899 (JP, A) Patent 2569356 (JP, B2) JP-B-52-48642 (JP, B2) (58) Fields investigated (Int. Cl. ⁶ , DB name) D21H 27/06

Claims (2)

(57) [Claims] A sheet is passed under a pressure of 100 kg / cm or more through a nip portion comprising at least one metal roll, wherein at least one metal roll is heated to a surface temperature of 80 to 200 ° C. A method for producing glassine paper, comprising drawing and performing a high smoothing treatment. 2. The method for producing glassine paper according to claim 1, wherein a nip portion made of a metal roll is provided between a drying step and a winding step of the paper machine.