JP2717635B2 - Chitin and chitosan - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a food packaging material, a pharmaceutical packaging material, a material intended for the human body, an agricultural material, a filter material, a wallpaper, a bran paper, a shoji paper, a tissue paper, a wet tissue paper, and a medical wrapping paper. The present invention relates to a chitin / chitosan-filled paper used for various applications requiring antibacterial properties and antifungal properties, including tatami paper.

[0002]

2. Description of the Related Art Chitin is a substance usually obtained by treating the shell of Benizwai crab with an acid and an alkali to remove calcium carbonate, proteins and other trace components, and chitosan removes the chitin. It is a substance obtained by acetylation treatment, and is known to have many excellent properties such as antibacterial and deodorant properties.

[0003] Since chitin / chitosan has a molecular structure very similar to that of cellulose, it has a good affinity for cellulose as a paper substrate, and the use of chitin / chitosan has a new effect. The paper that found it is being developed.

[0004] For example, a composition for surface coating of paper (JP-A-6
No. 4-14396), a recording medium for ink (Japanese Patent Laid-Open No.
No. 58784), chitosan-treated paper (Japanese Unexamined Patent Publication No. 1-1746)
No. 99), processed paper and a method for producing the same (Japanese Unexamined Patent Publication No. 2-127).
596).

In all of the above techniques, chitin is a solvent,
Chitosan is dissolved in an organic acid such as acetic acid or formic acid or another acid and used as an aqueous solution.Chemicals and various resins are added to this solution or aqueous solution and mixed with a paper base material, or coated and dried. The content is such that chitin / chitosan is neutralized and fixed on a paper substrate by treating with an alkali.

[0006]

According to the above prior art, chitin / chitosan is dissolved in a solvent or an acid to form an aqueous solution, and various chemicals are added to this chitin / chitosan solution or aqueous solution. It requires a step of dissolving chitosan and a step of adding various chemicals, which takes time and costs. Also, the acid or solvent used for dissolving the chitin / chitosan from paper products and the added chemicals have an adverse effect on the human body,
There is a problem that secondary pollution may occur due to acids and other chemicals.

In dissolving chitin and chitosan,
Chitin is very chemically stable and is extremely difficult to dissolve under ordinary conditions, and there are few suitable solvents. Chitosan can be easily dissolved with an acid, but 1-5% of high molecular weight ones It is only possible to dissolve it, and even if it has a low molecular weight, the concentration of chitosan solution of about 10% is the limit, and if it is so high, it is difficult to use it as it is because of its high viscosity. However, the use of the chitosan solution has a limit because the concentration must be extremely low.

[0008] In view of the above, the present invention provides a high concentration of chitin.
Chitosan-filled paper that enables the use of chitosan in a wide range, reduces the number of manufacturing steps, shortens work time and reduces costs, and aims to ensure safety for the human body. Is provided.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention has a paper base filled with 25 to 150 micron chitin and / or chitosan fine powder.

[0010]

According to the present invention, the paper substrate has a thickness of 25 microns to 15 microns.
The inclusion of 0 micron chitin or / and chitosan fine powder results in a paper product that does not impair the properties of conventional paper and has no surface roughness, and that chitin or / and / or chitosan is fine powder. Because of this, the surface area of chitin and / or chitosan in the paper substrate increases,
The amount of chitin and / or chitosan can be saved, and the antibacterial and deodorant properties of chitin and / or chitosan can be maximized.

Further, since chitin and / or chitosan are dissolved into a solution and no chemicals or resins are added to the solution, the number of manufacturing steps is reduced, and the working time and cost are reduced accordingly. Furthermore, since there is no addition of a solvent or a chemical for dissolving the chitin and / or chitosan, a paper product safe for the human body can be obtained, and there is no possibility of causing secondary pollution.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The chitin / chitosan-filled paper according to the present invention will be described in detail below. The present invention relates to a method for producing chitin or /
And chitosan (hereinafter referred to as chitin and chitosan) fine powder. As the paper base material, various papers made of pulp, synthetic fiber paper, synthetic fiber mixed paper, inorganic fiber paper, nonwoven fabric and the like are used.

Chitin is a substance usually obtained by treating the shell of Benizwai crab with an acid and an alkali to remove calcium carbonate, proteins and other trace components.
Chitosan is a substance obtained by deacetylating chitin.

The molecular weight of chitin / chitosan used in the present invention is preferably 50,000 to 2,000,000. The chitin / chitosan used in the present invention is preferably 10% or more of deacetylated.
%.

The present invention is characterized in that the above-mentioned 25 micron to 150 micron
Although chitin-chitosan fine powder emissions are Hama inner to said paper substrate, preferably 60 microns to 100 Mikuroin (235 mesh to 150 mesh) it is.

Organic substances are more difficult to pulverize than inorganic substances and are more susceptible to heat. Since chitin and chitosan, which are organic substances, are difficult to pulverize and are susceptible to heat, pulverization of chitin and chitosan is performed in order to enable pulverization by pulverization and to reduce the heat generated by the impact and friction during pulverization. In order not to lose the properties of chitin and chitosan and to enable micronization,
At the time of pulverization, chitin / chitosan is cooled to about -2 with refrigerant (liquid nitrogen).
The mixture is cooled at 0 ° C. to −100 ° C. for 1 to 20 seconds and pulverized.

The chitin / chitosan fine powder is to be filled in a paper base. In the filling, chitin / chitosan is added to the paper base in the paper preparation step and chitin / chitosan is added to the chemicals conventionally used. It is only necessary to mix the chitosan fine powder, and at this time, since chitin and chitosan are mixed, there is no need to add any additional chemicals or resins.

In the production of the chitin-chitosan-filled paper according to the present invention, in the preparation step in the middle of the conventional paper production process, chitin is added together with a chemical commonly used for a paper base together with chitin. -Only a step of mixing chitosan fine powder is added, and other steps are the same as the conventional steps.

Chitin / chitosan is a natural stable high molecular substance having an amino group in its molecule, and a cationic substance having a strong intermolecular bonding force due to the amino group.
Chemical structure is very similar to cellulose (raw material of paper), and ionically bonds with anionic substance cellulose. Since the fine powder of chitin / chitosan is ion-bonded to the cellulose in the paper base material and stabilized, the filling rate of the fine powder of chitin / chitosan to the paper base material is not particularly limited. However, the properties of chitin / chitosan, which are expected to have a low filling rate of fine powder of chitin / chitosan, are not sufficiently obtained, and if the filling rate is high, the hardness of the paper product becomes high and brittle, which restricts the use of the paper product. Will occur.

In order to obtain the expected properties of chitin / chitosan in a paper product, it is preferable that the chitin / chitosan filling rate is at least 0.3% or more. What is necessary is just to calculate the infill rate of.
For example, if the paper product is a food packaging material, a pharmaceutical packaging material, or a material intended for the human body (medical material field, MRS countermeasure paper, paper bandage, disposable diaper, etc.), the antibacterial property is particularly important. The filling rate of chitin / chitosan fine powder is preferably 0.5% or more.

In order to examine the antimicrobial effect of the present invention, chitin / chitosan fine powder was prepared by adding 1.0%, 1.5%, and 2.0% of 3%.
An antibacterial effect test was conducted on the various types of chitin-chitosan-filled paper at the Japan Spinning Inspection Association Testing Center, and the sterilization rate of all chitin-chitosan-filled papers was 99.9.
% Was obtained.

The molecular weight, the degree of deacetylation, the size of the fine powder particles, etc. of the chitin / chitosan of the present invention may be selected from the above ranges according to the purpose of use. For example, in the case of antibacterial properties, the molecular weight of chitin / chitosan is 5
It is particularly preferable that the viscosity is in the range of 10,000 to 300,000 and the degree of deacetylation is around 85%. In addition, in terms of deodorization, it is particularly preferable that the molecular weight of chitin / chitosan is 100,000 to 200,000 and the degree of deacetylation is around 70%.

[0023]

As described above, according to the present invention, paper base material
25-150 micron chitin / chitosan fine powder
Since the powder is included , a paper product without impairing the properties of conventional paper and having no rough surface is obtained, and since chitin / chitosan is a fine powder, the surface area of chitosan in the paper base material is reduced. As a result, the amount of chitin / chitosan can be reduced, and the chitin / chitosan can exhibit its antibacterial, deodorant, mold-proof, biocompatible, and immunological properties to the maximum, and dissolve the chitin / chitosan. Since there are no solvents or chemicals added to the product, paper products that are safe and human friendly to the human body are obtained, and there is no risk of causing pollution. And agricultural materials, filter materials, wallpaper, bran paper, shoji paper,
It can be used for various applications requiring antibacterial properties and antifungal properties, such as tissue paper, wet tissue paper, medical wrapping paper, and tatami paper. In addition, it will be possible to develop new paper products utilizing the biocompatibility and immunological activity of chitin and chitosan. In addition, a high concentration can be used for a molded article, and the range of use can be widened.

Furthermore, since chitin / chitosan is dissolved into a solution or a chemical or resin is not added to the solution, the number of manufacturing steps is reduced, and the working time and cost are reduced accordingly. Can be planned.

Claims (1)

(57) [Claims] 1. A paper substrate having a thickness of 25 to 150 microns.
A chitin / chitosan-filled paper, wherein the chitin and / or chitosan fine powder is contained therein.