JPH02127596A - Converted paper and production thereof - Google Patents

Abstract

PURPOSE:To obtain the title paper excellent in wet strength, resistance to water and alkali, antifungal nature, etc., and having receiving ability for water-based ink, rapid dryability and ink color-fading-proofness by bringing a paper base material into contact with an acidic aqueous solution of chitin and/or chitosan followed by drying. CONSTITUTION:A paper base material is brought into contact with an acidic aqueous solution of chitin and/or chitosan followed by, if needed, treatment with an alkali and drying, and furthermore, pref. making a heat treatment, thus obtaining the objective converted paper.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to processed paper with properties such as wet strength, water resistance, alkali resistance, antibacterial and antifungal properties, and a method for producing such processed paper. It is.

Conventional techniques Papers with improved strength and other properties are known, such as paper impregnated with viscose and paper made from disintegrated chitin.

Viscose-treated paper> Viscose-treated paper is pretreated by impregnating the paper base material with a dilute aqueous solution of viscose, then directly adhering viscose to this viscose-impregnated paper, and then coagulating it. Manufactured by recycling with liquid, washing with water, and drying.

This viscose treated paper is commonly used as casings for filling processed meat products such as ham and sausage.

<Chitin paper product> JP-A-56-68200 discloses a chitin paper product in which chitin extracted from the outer shell of crustaceans such as crabs and shrimps is disintegrated in water to obtain a chitin suspension, which is then made into paper. There is a disclosure about the body.

Japanese Unexamined Patent Publication No. 63-29000 discloses that chitin-based paper is produced by adding water to β-chitin, mechanically disintegrating it, and then fib-forming β-chitin alone or in combination with a valve to make paper. There is a disclosure about getting a body. It is stated that this chitin-based paper product is suitable for uses such as separation membranes, food wrapping paper, and medical materials.

Problem to be Solved by the Invention Although the viscose treated paper described in 1- meets the required performance as a casing for filling meat processed products, it requires a special process of recycling with a coagulating liquid, so it is difficult to process. There are problems such as the process being complicated, the production of sulfur oxides causing pollution, and the fact that reliable wet strength cannot be obtained unless the amount of hiscose supported by I4 is considerably increased. I feel sorry for you.

The chitin paper product described in 1- is made from chitin by mechanically shearing and fibrillating it before making paper, so it requires advanced paper-making technology and equipment, and the cost is extremely high when producing medium to small bottles. It is disadvantageous in that it is expensive and the quality tends to vary.

In view of this situation, the present invention aims to improve wet strength.

The purpose of this paper was to provide processed paper with properties such as water resistance, alkali resistance, and antibacterial and antifungal properties.

The means to solve the problem, that is, processed paper made from wood is made by adding chitin or / to the paper base material.
And it supports chitosan.

One of the methods for producing the pressurized paper of the present invention is characterized by contacting the paper base material with an acidic aqueous solution of chitin or/and chitosan and then drying it. In this case, it is particularly preferable to further perform heat treatment after drying.

Another method for producing processed paper of the present invention is characterized in that a paper base material is brought into contact with an acidic aqueous solution of chitin or/and chitosan, and then treated with an alkali.

The present invention will be explained in detail below.

<Paper base material> Paper base materials include wood valve, hemp pulp, flax valve,
In addition to various papers made from valves such as ramie valve, bamboo pulp, esparto valve, bagasse valve, polo valve, and linter pulp, synthetic fiber mixed paper, synthetic fiber paper, inorganic miscellaneous paper, nonwoven fabric, etc. can be used. .

There is no limit to the paper base material, and any suitable material can be used, but generally 5 to 70 g.
It is often selected from the range /m'.

<Chitin, chitosan> Chitin is a type of polysaccharide consisting of amine sugars in which each J-molecule has approximately 20,000 to 500,000 J-molecules, and D-glucosamine groups, which are acetylated amine groups, are bonded at β-1°4. It is made up of linear molecules and is typically made by crushing the shells of crustaceans such as crabs and shrimp. It can be obtained by treating with acid to remove calcium carbonate, treating with a concentrated alkali solution to remove proteins and other impurities, and if necessary, dissolving in e&hydrochloric acid and immediately precipitating.

Chitin can also be obtained from other sources, such as squid carapace.

Although chitin having different structures can be obtained depending on the raw material source and its treatment method, chitin obtained by any raw material source and treatment method may be used in the present invention.

Chitosan is also a basic polysaccharide made of glucosamine (2-amino D-glucose) with a molecular weight of about 20,000 to 500,000, and when looking at the unit part of the 0-molecule structure obtained by heating chitin with a concentrated alkali, , chitosan can be said to be a deacetylated product of chitin.

In the present invention, both chitin and chitosan can be used, but from the point of view of solubility, chitosan is easier to handle than chitin, and when producing chitosan from chitin, it is necessary to Mixtures or partial conversions of chitin and chitosan are obtained, which mixtures or partial conversions are more suitable for the purposes of the invention than either of them alone. Therefore, it is preferable to use a mixture or a partially converted product at the intermediate stage described above, or to use a "post-blend" of chitin and chitosan. When chitin and chitosan are used together, the weight ratio of both is 1=9.
It is desirable that the ratio is 9-90:LO1, especially 2:98-70:30.

Overall, the preferred rankings are as follows.

1. Mixture of chitin and chitosan or partial conversion of chitin to chitosan 2. Chitosan alone 3. Chitin alone (acidic aqueous solution) A suitable solvent for dissolving chitin and/or chitosan is an acidic aqueous solution of an organic acid or an inorganic acid. For example, acetic acid aqueous solution, lactic acid aqueous solution, citric acid aqueous solution, malic acid aqueous solution,
These include tartaric acid aqueous solution, adipic acid aqueous solution, fumaric acid aqueous solution, hydrochloric acid aqueous solution, sulfuric acid aqueous solution, phosphoric acid aqueous solution, boric acid aqueous solution, etc.

<Preparation of solution> A solution is prepared by dissolving chitin and/or chitosan in these acidic aqueous solutions. The concentration of chitin and/or chitosan in the solution can be determined as appropriate, but it is best to set it to about 1 to 20% by weight for ease of processing into the paper base material.1 to control the amount of chitin and/or chitosan attached to the paper base material. It is advantageous in this respect.

The solution can also contain water-soluble polymers, water-dispersible polymers, fillers, plasticizers, colorants, surfactants, and the like, if necessary.

<Contact method, support history> In order to support the above-mentioned solution on the paper base material, the paper base material is immersed in an acidic aqueous solution of chitin or/and chitosan.
Contact is made by means such as spraying or coating.

The amount of chitin and/or chitosan supported on the paper base material can be set within a wide range depending on the type of paper base material and its purpose, but - in the membrane, it is often set at 0.5 to 30 g/m' on a dry basis. . If the supported amount is too small, the effect of improving the properties of the resulting processed paper will be insufficient, and if the supported amount is too large, the cost will increase, which is economically disadvantageous.

<Drying and heat treatment route> After bringing the acidic aqueous solution of chitin and/or chitosan into contact with the paper base material, it is washed with water if necessary (this washing step is often omitted), and then dried to remove chitin. or/and fixing chitosan to a paper substrate.

As a drying method, a heating drying method is usually adopted, and in this case, the drying temperature is about 50 to 180°C, especially 60 to 130°C.
Approximately ℃ is appropriate.

Further heat treatment after dry blasting further improves the wet strength of the resulting processed paper. The heat treatment temperature should be about 80 to 180°C, especially about 90 to 160°C.

However, the above-mentioned drying temperature and heat treatment temperature are flexible depending on the drying time and heat treatment time, so the above-mentioned temperature range is only a guideline.

<Alkali treatment route> It is also possible to treat the paper base material with an alkali after contacting it with an acidic aqueous solution of chitin or/and chitosan.
Chitin or/and chitosan can be fixed to a paper substrate. Washing with water and drying may be performed before the alkali treatment.

As the alkali, hydroxides, salts, amines, etc., which exhibit alkalinity when made into an aqueous solution, are used.

After alkali treatment, it is normal to wash with water and dry.
Depending on the case, rough heat treatment may be performed after drying.

<Comparison of both routes> When the drying (or drying and heat treatment) route described in 1- is compared with the alkali treatment route, the former is more advantageous.

<Applications> The processed paper of the present invention can be used as food packaging materials (casings for filling processed meat products, etc.), pharmaceutical packaging materials, materials intended for the human body (medical materials, bandages, paper bandages, disposable diapers, etc.), materials for four industries, It can be used for a wide variety of purposes, including filter materials, wallpaper/fusuma paper, printing paper, office paper, computer output paper (water-based jet ink output paper, etc.), and card paper.

The processed paper of the present invention, which has chitin or/and chitosan supported on the paper base material, has high wet strength, as well as excellent water resistance and alkali resistance, and antibacterial and antifungal properties. It has various desirable properties such as high safety for the human body, ability to accept aqueous ink, ability to dry quickly and prevent ink from fading.

Therefore, it is particularly useful in applications that are used in humid conditions or that may be exposed to humid conditions.

The processed paper of the present invention can also be subjected to other treatments (for example, viscose impregnation treatment) or laminated with other substrates (for example, paper, nonwoven fabric, plastic film, metal foil).

Example Next, the present invention will be further explained with reference to Examples.

Hereinafter, "parts" and "%" are expressed on a weight basis.

<Manufacture of processed paper 1> Example 1 A solution with a composition consisting of 0.5 parts of chitin (manufactured by Nanyo Kasei Co., Ltd.), 0.5 parts of chitosan (manufactured by Nanyo Kasei Co., Ltd.), 1 part of acetic acid, and 98 parts of wood was prepared. Then, in this solution, 20 g of basis weight is added.
/rn' Japanese paper was impregnated for a short time and then pulled out at 80℃.
It was dried with hot air for 2 minutes. The total loading of chitin and chitosan was l g/rn' on a dry basis.

In addition, the dried processed paper was further heat-treated at 130°C for 2 minutes.

Example 2 Partial conversion product when producing chitosan from chitin (10% chitin median, 90% chitosan unit) 1 part, acetic acid 1 part
A solution having a composition of 98 parts of wood and 98 parts of wood was prepared, and Japanese paper with a basis weight of 20 g/m 2 was impregnated in this solution for a short period of time, then peeled and dried with hot air at 90° C. for 2 minutes. The supported chitin-chitosan partial conversion product tJ' is 3 gem' on a dry basis.
Met.

Further, the dried processed paper was further heat-treated at 120° C. for 3 minutes.

Example 3 A solution having a composition of 1 part of chitosan, 1 part of acetic acid and 98 parts of water was prepared, and Japanese paper with a J+ group of 20 g/m' was impregnated in this solution for a short period of time. It was dried with hot air for 5 minutes. Chitin's temporary stitching is dry, (5 g /
The pressurized paper was further heat-treated at 130° C. for 2 minutes after being kept dry.

Comparative Example 1 A 1.5% aqueous solution of hiscose was prepared, and Japanese paper with a size of 20 gems was impregnated in this aqueous solution for a short period of time, then pulled, the viscose was coagulated and regenerated, and dried with hot air at 80°C for 2 minutes. The amount of viscose supported was 1 g/dry basis.
It was m'.

Further, the dried viscose-impregnated paper was further heat-treated at 130° C. for 2 minutes.

Comparative Example 2 The viscose-treated paper obtained in Comparative Example 1 was further impregnated with viscose, and the viscose was coagulated and regenerated to produce viscose-added T paper. The total amount of viscose supported is 4 on a dry basis.
0g/m''.

Comparative Example 3 Basis weight used in Examples 1 to 4 and Comparative Examples 1 to 2: 20 g
/rn' Japanese paper.

〈Measurement of wet tensile strength〉 For each processed paper obtained in two pairs and the Japanese paper of Comparative Example 3,
The tensile strength in the transverse direction was measured according to JIS P-8135r "Wet tensile strength test method for paper and paperboard". However, Comparative Examples 1 and 2 were washed by immersing them in 80° C. warm water for 5 minutes, dried, and then subjected to measurement.

The results are shown in Table 1.

Table (supported amount is dry basis) <Other properties> The processed papers obtained in Examples 1 to 3 (after drying and after heat treatment) and the Japanese paper of Comparative Example 3 were pasted on a bathroom wall, and mold We investigated the occurrence of mold on the Japanese paper of Comparative Example 3, but no mold was observed on the processed paper that was stirred in Examples 1 to 3. Ta. The same was true for the processed papers of Examples 4 and 5, which will be described later.

In addition, when written on the processed paper obtained in Examples 1 to 3 (after drying and after heat treatment) with water-based ink,
It was confirmed that the water-based ink receptivity, quick drying ability, and ink fading resistance were all excellent. The same was true for the processed papers of Examples 4 and 5, which will be described later.

<Production of processed paper 2> Example 4 Chitin 0.3! , 1.7 parts of chitosan, 2 parts of acetic acid, and 96 parts of wood.
Washi paper of Mofit 20 g/m' was impregnated for a short time, dried with hot air at 90°C for 15 minutes, neutralized with an aqueous sodium carbonate solution, and washed with water. After washing with water, it was dried with hot air at 90°C for 5 minutes. The total loading of chitin and chitosan was 10 g/rn' on a dry basis.

The wet tensile strength of the obtained processed paper is looog/15+o
It was +s.

Example 5 A solution having a composition of 1 part of chitosan, 1 part of acetic acid, and 98 parts of water was prepared, and kraft paper with a basis weight of 20 g/m was impregnated in this solution for a short time, then taken out and heated at 80°C for 2 minutes. After drying with hot air, it was heat-treated at 130°C for 5 minutes.The amount of chitosan supported was 5 g/rrr'' after drying and heat treatment.

The wet tensile strength of the resulting processed paper was 960 g/15 cm.

The wet tensile strength of the kraft paper used above is 320
g/15mm.

Effects of the Invention The processed paper of the present invention has high wet strength, excellent water resistance and alkali resistance, exhibits antibacterial and antifungal properties, and is highly safe for the human body.
It has various properties such as preventing ink from fading.

Since paper is used as the base material, desired physical properties can be obtained by selecting the paper base material according to the purpose and use.

In addition, the process described in -1- can be achieved by simply drying (or drying and heat treatment) or alkali treatment after attaching it to the cloth, without requiring complicated processes like those required when producing viscose-treated paper or chitin paper products. Processed paper with such excellent properties can be obtained, so there is no variation in quality, and there is also the advantage that it can be used not only for large-scale production but also for medium- to small-quantity production.

Patent applicant: Fujimori Industries Co., Ltd. Patent applicant: Osaka Godo Co., Ltd.

Claims (1)

[Claims] 1. Processed paper in which chitin and/or chitosan is supported on a paper base material. 2. The processed paper according to claim 1, wherein the amount of chitin and/or chitosan supported on the paper base material is 0.5 to 30 g/m^2 on a dry basis. 3. A method for producing processed paper, which comprises contacting a paper base material with an acidic aqueous solution of chitin or/and chitosan and then drying it. 4. The manufacturing method according to claim 3, further comprising performing a heat treatment after drying. 5. A method for producing processed paper, which comprises bringing a paper base material into contact with an acidic aqueous solution of chitin or/and chitosan, and then treating it with an alkali.