JP3282168B2 - Manufacturing method of high transparency paper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to paper of high transparency which is easy or renewable, and relates to paper used for medicine, food packaging, envelopes with windows and other wide applications.

[0002]

2. Description of the Related Art Sheets and films made of synthetic high molecular substances such as polyester, polystyrene, and polypropylene have been used as transparent papers conventionally used in medicine, food packaging, window envelopes, and many other applications. Or a composite paper obtained by laminating a highly transparent sheet and film on a low transparent paper.

However, these synthetic papers and laminated papers cannot be mechanically defibrated in the defibration step in the defibration process, and the recycled pulp is produced from waste paper. In doing so, it becomes a significant obstacle.

Therefore, when producing highly transparent paper,
Various methods have been adopted without using the synthetic polymer substance. That is, a: a method in which pulp obtained by highly beaten vegetable fibers is made into paper, and dried and compressed by a high nip super calender. B: In the above method a, a polymer substance having a lower melting point than a dryer of a paper machine is used. A method of impregnating air to remove air to measure transparency; c: a method of impregnating or applying low-density paper with paraffin wax or a polymer substance having a relatively similar refractive index to cellulose to impart transparency. .

[0005] Originally, β-glucose, which is a component of pulp, is a nearly colorless and transparent substance having a 1,4-β-glucoside bond, and is composed of bound microfibrils, and cellulose composed of aggregated fibrils. Fibers are highly transparent, as seen in cellophane, as long as there are no contaminants or voids, and the presence of those voids alters the light refractive index and causes reflection, increasing the opacity, and conversely, the transparency Falling.

[0006] As a selection of the type of pulp for making transparent paper, there is also a trial of fine mechanical pulp, which is easily discolored by light or heat. It is often used as a raw material. Since transparent paper is required to be thin and high in strength, softwood is preferable to hardwood as a raw material for pulp. In some cases, hemp pulp is used.

[0007] Among chemical pulps, sulfite pulp is used rather than kraft pulp, although the yield is low. However, in addition to lowering the strength of paper on one side, the pulp is refined and becomes expensive, resulting in a significant increase in cost. Becomes

[0008] Generally speaking, transparent paper includes glassine paper, oil paper, wax paper and the like. In order to obtain glassine paper in which the fiber gap of a paper sheet is filled with fine fibers, plant fiber pulp must be highly refined. The paper is made by viscous beating, but in this case, the power consumption for the beating is remarkable, the beating blade is often damaged, and it has a disadvantage that it is very uneconomical including that it takes a long time.

In the case of impregnating a high molecular substance having a melting point lower than that of a paper machine dryer, the high molecular substance adheres to the dryer during drying of the dryer, and a special removing device is required to remove the high molecular substance. Or
Because it involves work to stop the paper machine and remove the deposits,
Not only is it uneconomical, but also has the disadvantage of significantly reducing productivity.

As a prior art of the present invention, Japanese Patent Laid-Open No.
682, the present invention introduces a transparent paper in which pulp fiber gaps are filled with starch or ungelatinized starch is bonded to the fiber surface, but when starch is internally added, it adheres to the paper machine dryer. And has the drawback of causing soiling like high-molecular substances.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to improve various drawbacks in the above-mentioned conventional method, and there is a problem of adhesion of a polymer substance and ungelatinized starch, polyester, polystyrene, and the like. As a method of solving all the non-renewable problems of synthetic paper and laminated paper made of polyolefin sheets or films, and the problem of power consumption for advanced beating, the addition of cellulolytic enzyme in the beating process of pulp A method for preparing pulp excellent in producing recycled paper by beating pulp.

[0012]

The configuration of the present invention is as follows. In a method for producing high transparency paper using pulp composed of vegetable fiber, CMC activity of 2500 to 250
A process for producing highly transparent paper, characterized in that a cellulose-degrading enzyme of 3000 U / ml is beaten in a pulp beating step by adding 0.01 to 0.2% by weight of the pulp, followed by beating the paper.

Cellulase is used as cellulase, and its CMC activity is 2500-3000 U / ml.
It has been noticed that those which have a particularly remarkable effect. Here, 1 U (unit) means an amount of an enzyme that generates a reducing terminal equivalent to 1 μmol of glucose per minute using CMC (carboxymethylcellulose) as a substrate. Compared with the case where the cellulase is not added, the pulp is very easily refined, and the beating load is significantly reduced,
Damage to the beating blade was reduced, and recycled paper was effectively obtained.

By using the above-mentioned cellulase having CMC activity, when the pulp slurry is made into paper with high moisture and then the sheet is compressed in a super calendering step, the compression is extremely easily performed. During production, we were able to solve all power consumption and other technical problems.

Since the present invention is manufactured using 100% wood pulp, the disintegration is equivalent to that of conventional glassine paper manufactured conventionally.

A possible point of the beating action according to the present invention is that the prepared pulp to which the cellulose-degrading enzyme (cellulase) is added is subjected to the beating process because water molecules are adsorbed to the amorphous region of cellulose and the internal swelling of the pulp proceeds. It can be seen that the fiber cutting in the process can be performed with low energy, and the beating power per unit throughput can be reduced.

The reduction in the beating load reduces the wear damage of the beating blade. Compared to the conventional method in which cellulose-degrading enzyme (cellulase) is not added, when the pulp is prepared by adding this, the drying energy of the papermaking dryer is reduced by 5%.
〜１０10% increase. Further, the prepared pulp to which the cellulolytic enzyme (cellulase) is added has an effect of delaying the evaporation rate of water, and it can be seen that the pulp has an extra amount of water inside the pulp.

The super calendering step is a step of drying and compressing the papermaking base paper to remove air in the paper layer to increase the density of the paper layer to obtain a highly transparent paper. It can be seen that the paper base paper having a large amount of water inside the pulp and the paper base paper having a small amount of water have different water separation / desorption speeds in drying and compression, and that the paper base paper having a large amount of internal water has a property of being easily compressed.

Next, the present invention will be described in detail based on embodiments. Treatment conditions-The treatment conditions of the cellulose-degrading enzyme for the pulp are selected and implemented depending on the temperature, pH, time, and the amount of the enzyme added. However, it is necessary to control the pulp before the pulp generates sugar and proceeds to lower molecular weight. There is. If this setting is not appropriate, the molecular weight of the pulp is excessively reduced, the paper quality is reduced, and the function as paper is lost. The processing conditions that satisfy the paper quality strength as its function are as follows: temperature: 10 to 50 ° C., p
H: 5 to 8; time: 1 to 3 hours; enzyme addition amount: 0.01 to 0.2% by weight based on pulp, but not limited thereto.

[0020]

Example 1 A 3% pulp slurry obtained by disintegrating 1000 kg of NBKP was adjusted to pH 6.5 and a temperature of 25 ° C., and then subjected to cellulolytic enzyme (PERGALA manufactured by GENENCOR).
SEA-40) was added to the pulp at 0.05% by weight and treated for 2 hours. The prepared pulp was beaten for 180 minutes at a load of 45 amps of a double disc refiner, and then the water content was 32%.
As a result, a paper roll of 40 g / m ² was obtained. Roll the paper at 100 ° C. roll speed, 320 mm / min speed, load 288
The mixture was heated and compressed by a g-cm super calender until the water content became 5%, and then the density, transparency and disintegration were measured. The measured values are shown in Table 1 below.

[0021]

Example 2 A 3% pulp slurry obtained by disintegrating 1000 kg of NBKP was adjusted to pH 6.5 and a temperature of 25 ° C., and then subjected to cellulolytic enzyme (PERGALA manufactured by GENENCOR).
SEA-40) was added to 0.07% by weight of pulp and treated for 2 hours. The prepared pulp was beaten for 180 minutes at a load of 50 amps of a double disc refiner, and then water content was 32%.
As a result, a paper roll of 40 g / m ² was obtained. Roll the paper at 100 ° C. roll speed, 320 mm / min speed, load 288
The mixture was heated and compressed by a g-cm super calender until the water content became 5%, and then the density, transparency and disintegration were measured.

[0022]

Comparative Example 1 A 3% pulp slurry obtained by disintegrating 1000 kg of NBKP was adjusted to pH 5.5 and a temperature of 25 ° C., and beaten for 130 minutes with a load of 50 amps of a double disc refiner. After adding 10% by weight of a low melting point corn starch (PPS-4 manufactured by Sanwa Starch Co., Ltd.) to the beating raw material, the product was dried at a paper making dryer temperature of 100 ° C. and the water content was 32% and the product was 40 g / m2
to obtain a paper take-up of m ^2. Roll the paper at a roll temperature of 100
℃, speed 320mm / min, heated and compressed to 5% moisture in a super calender with a load of 288g-cm,
Thereafter, the density, transparency and disintegration were measured.

[0023]

[Comparative Example 2] A 3% pulp slurry obtained by disintegrating 1000 kg of NBKP was adjusted to pH 5.5 and a temperature of 25 ° C, beaten for 180 minutes with a load of 54 amps of a double disc refiner, and then dried at 32% water to obtain 40 g / g of product rice tsubo. to obtain a paper take-up of m ^2. Roll the paper at a roll temperature of 100 ° C and a speed of 32.
It was heated and compressed by a super calender with a load of 288 g-cm at 0 mm / min until the water content became 5%, and then the density, transparency and disintegration were measured.

[0024]

Comparative Example 3 The film used for the transparent part of the envelope with a window was slit into 2 cm square to observe the disintegration.

[0025]

[Comparative Example 4] The paper used for the transparent part of the envelope with window,
The portion on which the synthetic resin was applied was slit into 2 cm squares, and the disintegration was observed.

[0026]

[Table 1] In the table, the density is obtained by dividing rice tsubo by thickness. The transparency was measured using a Murakami transparency meter. Beating power consumption is 100% of Comparative Example 1.
Was compared. The beating blade abrasion degree was 100 in Comparative Example 1.
%. As for the dryer stain, the dryer stain in papermaking was visually observed. The degree of disaggregation was measured by using a home mixer at a sample concentration of 1% for 5 minutes and then visually observed for disintegration.

[0027]

As described in detail above, cellulose degrading enzyme (cellulase) is used in a pulp beating process in a pulp beating process.
By adding 01 to 0.2% by weight, a remarkable effect of promoting swelling of the pulp and improving the beating efficiency is exhibited, and hydration of the pulp is promoted, and a high-quality pulp having high transparency by calendering treatment is obtained. Preparation was possible, and pulp excellent in disintegration property without waste of beating power was able to be provided.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-316899 (JP, A) JP-A-6-506732 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) D21D 1/00-5/28 D21H 11/00-27/42 C12S 3/08

Claims (1)

(57) [Claims] 1. A method for producing highly transparent paper using pulp comprising vegetable fiber, comprising the steps of:
In a pulp beating process, a cellulose-degrading enzyme of 000 U / ml is added in an amount of 0.01 to 0.2% by weight based on pulp,
Beating treatment by setting the treatment conditions of the decomposing enzyme to pH 5 to 8
And the slurry is made into paper to reduce the water content of the base paper to 32.
High high transparent paper manufacturing method characterized by and this <br/> to super calender cliff while maintaining approximately%.