JPH06294094A - Production of paper - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a method for producing paper having high wet strength and significantly improved alkali resistance. [Constitution] 0.5 to 3% by weight of polyamide epichlorohydrin resin is added to the pulp slurry based on the weight of absolutely dry pulp, and then guar gum is added in the range of guar gum: polyamide epichlorohydrin resin = 0.5: 1 to 1: 1 for papermaking.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing paper having good wet strength and alkali resistance (that is, strong resistance to alkaline liquid). More specifically, the present invention is a casing base paper used for a fibrous casing for filling meat products such as ham and sausage,
The present invention relates to a method for producing paper having moisture resistance and alkali resistance, which is suitable as a base paper for tea bags for filling tea for drinks.

[0002]

2. Description of the Related Art Processed meat products such as ham and sausages are manufactured by filling a tube-shaped casing with a kneaded product prepared by mixing raw materials and then subjecting it to heat treatment, sterilization treatment, smoke treatment and the like. This casing includes natural casing and artificial casing (cellulose casing, collagen casing, plastic casing, fibrous casing, etc.). The artificial casing is cheaper and more hygienic than the natural casing, and the product size is constant. It is widely used because of its advantage.

However, the cellulose casing has the drawbacks of low strength and weakness to humidity, and the plastic casing cannot be smoked. Therefore, large-sized loin ham and press ham have hitherto been used. For use, a strong fibrous casing that is smokeable and post-treated is used.

The fibrous casing base paper is a paper base made of cellulose pulp impregnated with viscose,
Coagulated and regenerated, this method is disclosed in US Pat. No. 2,105,273.

Viscose has a cellulose content of 7% by weight.
It is an aqueous solution containing 5% sodium hydroxide and 6% sodium hydroxide. Therefore, the paper base for impregnating viscose is required to have wet strength and alkali resistance (strong resistance to alkaline liquid). In order to impart wet strength and alkali resistance that can withstand the above-mentioned impregnation of viscose to such a paper substrate, as disclosed in U.S. Pat.Nos. 3,135,613 and 3,275,456, a diluted viscose liquid (cellulose content is used). Pre-impregnation (about 1%) and regeneration treatment are performed. In addition, Japanese Patent Publication 4-16129
The publication discloses treating cellulose pulp fibers with chitosan or a chitosan salt.

Further, Japanese Patent Publication No. 45-3948 discloses a method of treating fibers with a cationic alkali-curing resin such as polyamide epichlorohydrin resin and polyethyleneimine. US Pat. No. 3,484,256 discloses the use of these cationic alkali curing resins and polyacrylamide resins, and US Pat.
No. 6,696 describes a method of imparting alkali resistance with a cationic alkali curing resin and carboxymethyl sodium cellulose. Japanese Examined Patent Publication No. 63-38480 discloses a cationic alkali curing resin, hydroxyethyl cellulose, carboxymethyl sodium cellulose,
A method for imparting alkali resistance with a non-viscose-based film forming agent such as polyvinyl alcohol, starch and the like and polyalkyleneimine is described.

These are treated by adding or impregnating the above-mentioned chemicals in the state of cellulose fiber slurry or fiber web. In addition, various techniques for improving wet strength and alkali resistance have been developed. Has been done. As described above, the base paper for the fibrous casing is usually provided with some form of wet resistance and alkali resistance capable of withstanding the adhesion of viscose.

However, none of the conventional techniques is sufficient for the effect of improving the wet strength and the alkali resistance, and in order to process with viscose, the wet strength and the alkali resistance of the paper substrate should be further improved. The current situation is that improvement is desired.

On the other hand, the base paper for a tea bag does not require alkali resistance as high as the base paper for a fibrous casing, but is required to have good water absorption and high wet strength. British Patent No. 1,111,165 describes a method of treating a sheet composed of a cellulose pulp fiber with a polyamide epichlorohydrin resin and carboxymethyl cellulose, but the base paper for tea bags by this method has low alkali resistance and is an alkaline herbal tea. Not suitable for tea bags for. Further, in U.S. Pat.No. 2,698,793,
It is described that a hydrophobic sizing agent and an alkyleneimine resin are added and used, but this method is unsuitable for tea bags because water repellency occurs in the obtained base paper and water absorption also decreases. There are drawbacks.

[0010]

SUMMARY OF THE INVENTION In view of the above situation, the inventors of the present invention have made the pulp into a cationic resin in a slurry state in order to improve the wet strength and alkali resistance of a paper base material made from the pulp. As a result of diligent research on the treatment with an anionic resin, the treatment of pulp with a combination of polyamide epichlorohydrin resin and guar gum resulted in significantly better wet strength and alkali resistance than the paper substrate prepared by the prior art. The inventors have found that products can be obtained and completed the present invention.

An object of the present invention is to provide a method for producing paper which is extremely excellent in wet strength and resistance to alkaline liquid.

SUMMARY OF THE INVENTION The present invention is a method for producing a paper, which comprises adding a polyamide epichlorohydrin resin and guar gum to a pulp slurry to make a paper.

The polyamide epichlorohydrin resin preferably used for the present invention is a water-soluble polymerization reaction product of epichlorohydrin and a polyamide having a secondary amine group. Epichlorohydrin undergoes a polycondensation reaction by reacting with a secondary amine group in the polyamide, converting the secondary amine group to a tertiary amine group, and an adjacent epoxy ring also serves for the polycondensation reaction. Polyamides derived from polyalkylene polyamines and saturated or unsaturated aliphatic or aromatic polycarboxylic acids having 3 to 10 carbon atoms are especially preferred. Typical examples of such substances are:
It is a water-soluble epichlorohydrin polyamide reaction product (for example, sold under the trade name "WS570" manufactured by Japan PMC).

The guar gum that can be preferably used in the present invention is galactonan man extracted from the endosperm of seeds of annual beans (Cyamopsis tetragonolobus) growing in India, Pakistan, Texas, USA, etc. Is
It has a structure in which D-mannopyranose is α (1,6) -linked to D-galactopyranose in some places on the main chain elongated by β (1,4) -bonding. The molecular weight is about 220,000 and the ratio of galactose to mannose is 1: 4. Anionic guar gum is preferred for use in combination with the polyamide epichlorohydrin resin, and particularly carboxymethylated guar gum (for example, a representative example of such a substance is Meyhall Chemical Co., trade name: maployd) is preferably used.

The above-mentioned guar gum is a polymer, has many OH groups in the molecule, and forms many hydrogen bonds with the OH groups of cellulose. In addition, since the straight-chain mannose contained in guar gum has a β-bond and extends straight, all OH groups are exposed and bonding with the OH groups of cellulose is extremely easy. Both mannose and galactose of guar gum have OH groups at cis positions, and they reinforce adjacent OH groups, so that a strong hydrogen bond is formed with the OH groups of cellulose.

As can be seen from the above description, the addition of guar gum to the cellulose pulp increases the binding strength of cellulose, and in the anionic guar gum, the cationic polyamide epichlorohydrin resin is more easily fixed. This further improves the bond strength. In addition, guar gum also has an effect of improving the texture of the paper base material when making paper with a paper machine using the pulp treated as described above as a raw material, which is also a factor for improving strength.

The addition rate of the polyamide epichlorohydrin resin for the present invention is 0.5% based on the absolute dry weight of the pulp used.
~ 3% by weight. If the addition rate is less than 0.5% by weight, the wet strength of the obtained paper will not be sufficiently expressed, and if the addition rate exceeds 3%, the strength will reach the saturated state, and further addition will be economically unsatisfactory. Profit is generated.

On the other hand, the addition of guar gum that can be preferably used in combination is in the range of 0.5: 1 to 1: 1 by weight ratio of guar gum: polyamide epichlorohydrin resin. When the addition ratio of guar gum is less than 50% of polyamide epichlorohydrin resin, the effect of enhancing the wet strength is small, and when it exceeds 100%, the expression of the wet strength reaches a saturated state, which is not economical and the potential of the pulp slurry is inclined to the negative. It is not suitable because it is excessively performed and the texture collapses during paper making.

Examples of the paper base material for the present invention include non-wood fibers such as wood pulp such as bleached kraft pulp, hemp (manila hemp, sisal hemp, flax, cannabis, jute), kozo, mitsumata, etc. ) Or the like, or a pulp obtained by appropriately selecting and mixing these pulps, preferably a paper obtained by making a paper with a known wet paper machine using hemp pulp as a paper stock is suitably used.

When the chemicals are added to the pulp, the chemicals may be added to the pulp slurry in a usual papermaking method, for example, in a mixing tank or a mixing box. The order of adding the chemicals is not particularly limited, but it is preferable to add the epichlorohydrin resin first and then add the guar gum. Pulp is preferably used in an unbeaten state (freeness 650 to 750 ml CSF) to make porous paper, but depending on the application, the beating strength increases binding strength. Alternatively, a part may be used.

The basis weight of the paper substrate depends on the desired application.
For example, 15-30 for fibrous casing base paper
g / m ^2, appropriately selected and used as the range of 10 to 30 g / m ² in order of the base paper for tea bags.

According to the purpose, the paper base material produced as described above may be diluted with a dilute aqueous solution of viscose in order to impart higher wet strength and alkali resistance in the case of, for example, fibrous casing base paper. (1 to 2% concentration) and post-treatment may be performed by a conventional technique of performing a regeneration treatment or another technique.

The present invention is a method for producing paper in which pulp is treated with a cation resin and an anion resin and then made into paper. The resulting paper base material has excellent wet strength and, at the same time, excellent resistance to alkaline liquids. Therefore, it is suitably used not only as a base paper for fibrous casings but also as a base paper for filters for tea bags, flavor bags and the like.

[0023]

The present invention will be described in more detail with reference to the following examples, but of course the present invention is not limited thereto. Incidentally,% in the examples and comparative examples means% by weight unless otherwise specified.

Example 1 Unrefined (freeness 680 ml CSF) commercial Philippine hemp pulp (product number: IPP-42) slurry (2.5% concentration) was added to polyamide epichlorohydrin resin (WS) per absolute dry pulp weight.
570, manufactured by Japan PMC) and 0.6% carboxymethylated guar gum (Maployd 870 manufactured by Meyhall Chemicall).
6% (Gua gum: polyamide epichlorohydrin resin =
1: 1), added in this order, mixed well and mixed to make a paper stock, and a paper base material having a basis weight of 23 g / m ² was prepared in a laboratory paper machine. The wet tensile strength and alkali resistance of the obtained paper base material were measured by the following methods to evaluate their quality.

Test method (1) Wet tensile strength According to JIS P 8135. (2) Alkali resistance According to JIS P 8135, the wet tensile strength was measured after immersing in a 6% concentration sodium hydroxide aqueous solution for 10 minutes instead of water.

Example 2 Example 1 except that 2.8% of polyamide epichlorohydrin resin (WS570) was added to the dry pulp weight and 2.8% of carboxymethylated guar gum (Maployd 870) was added (guar gum: polyamide epichlorohydrin resin = 1: 1). A paper base material was prepared in the same manner as described above, and the quality of the obtained paper base material was evaluated.

Example 3 Example 1 except that polyamide epichlorohydrin resin (WS570) was added in an amount of 2.8% based on absolute dry pulp weight and carboxymethylated guar gum (Maployd 870) was added in an amount of 1.5% (guar gum: polyamide epichlorohydrin resin = 0.54: 1). A paper base material was prepared in the same manner as described above, and the quality of the obtained paper base material was evaluated.

Comparative Example 1 A paper base material was prepared in the same manner as in Example 1 except that only polyamide epichlorohydrin resin (WS570) was added in an amount of 0.6% based on the absolute dry pulp weight, and the quality of the obtained paper base material was evaluated. .

Comparative Example 2 A paper base material was prepared in the same manner as in Example 1 except that only 3.2% of polyamide epichlorohydrin resin (WS570) was added based on the weight of absolutely dry pulp, and the quality of the obtained paper base material was evaluated. .

Comparative Example 3 A paper base material was prepared in the same manner as in Example 1 except that only carboxymethylated guar gum (Maployd 870) was added in an amount of 3.2% based on the absolute dry pulp weight, and the quality of the obtained paper base material was evaluated. evaluated.

Comparative Example 4 Example 1 except that polyamide epichlorohydrin resin (WS570) was added in an amount of 2.8% based on absolutely dry pulp and carboxymethylated guar gum (Maployd 870) was added in an amount of 5.0% (guar gum: polyamide epichlorohydrin resin = 1.79: 1). A paper base material was prepared in the same manner as described above, and the quality of the obtained paper base material was evaluated.

Table 1 shows the evaluation results of the paper substrates obtained in Examples 1 to 4.

[0033]

[Table 1]

As can be seen from Table 1, by internally adding the polyamide epichlorohydrin resin and guar gum to the pulp, the paper base material according to the present invention has high wet strength and excellent alkali resistance (Examples 1 to 3). However, when the polyamide epichlorohydrin resin is added alone (Comparative Examples 1 and 2) and when guar gum is added alone (Comparative Example 3), the co-alkali resistance is poor and is not suitable for practical use. Even when guar gum and polyamide epichlorohydrin resin are used together, when the ratio of guar gum used is high, the bond strength is still lower than the amount of the drug used, but still at a level suitable for practical use (Comparative Example 4). However, in this case, the obtained paper base material is severely damaged, and cannot be commercialized.

[0035]

As described in detail above, the present invention has the effect of providing a method for producing paper which has high wet strength and can greatly improve alkali resistance.

Claims (1)

[Claims] 1. A method for producing paper, which comprises adding a polyamide epichlorohydrin resin and guar gum to a pulp slurry to make a paper.