JPS58208499A - Production of polyester fiber containing paper - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing paper containing polyester fibers, and its purpose is to improve the dispersibility of polyester fibers in the papermaking process, and to produce paper with good formation and excellent paper strength. The purpose of the present invention is to produce paper containing polyester fibers and at the same time increase productivity.

Conventionally, natural cellulose has been used as a raw material for papermaking.

Rayon and vinylon have been mainly used, but due to higher raw material costs and higher performance requirements, polyester fibers are recently replacing some of the raw materials for papermaking. It is a round shape with excellent physical properties, heat resistance, 1-dimensional stability, and hydrophobicity.
It is thought that the replacement by polyester fibers will progress rapidly. However, conventional polyester fibers for papermaking are
Dispersibility is very poor, so the excellent properties of polyester fibers cannot be fully utilized.Furthermore, the poor dispersibility is compensated for by lowering the fiber concentration during paper making, resulting in poor productivity. It had

Most of the conventional short polyester fibers have been used as raw materials for spinning, so in consideration of card passing properties, antistatic properties, convergence properties, and roller winding properties, lauryl phosphate potassium salt, etc. Anionic surfactants, nonionic surfactants such as ethylene oxide adducts of aliphatic alcohols, and cationic surfactants such as quaternary ammonium salts are added alone or as a mixture. This book has almost no effect on improving the dispersibility of polyester fibers, or even if it does have a very small effect.

It is very difficult to uniformly disperse thin PI and lI fibers with long fibers.

When making paper such as vinylon and rayon, a sticky agent is usually used for the purpose of improving fiber dispersibility and adjusting water resistance. As a sticky agent, Boliedere/Oxide,
Polyacrylamide, molasses, etc. are used, but the dispersibility improvement effect of this viscosity agent is not very large, and the viscosity-enhancing effect for adjusting F aqueous properties is the main one.

In addition, for the purpose of improving dispersibility, surfactants are added during paper making (for example, Japanese Patent Publication No. 47-19
In JP 562, for vinylon or rayon,
It has been proposed to use ethylene chloride, 2 moles of stearylamine, and the like. Furthermore, polyoxyethylene sorbitan monolaurate is added to the dispersibility of nylon fibers.

Cetyltrimethylammonium chloride and the like are said to be effective.

However, these adhesives and surfactants have little effect on improving the dispersibility of polyester fibers. Up until now, polyester fibers as raw materials for papermaking have mostly been used as fillers (i.e., the proportion of polyester fibers is less than 50%), and have been used loosely as main fibers. Not yet. Therefore, it seems that even if the dispersibility of the polyester fibers was a little poor, it did not pose a major problem. However, when attempting to make paper using polyester fibers as the main fiber in order to meet the increasingly sophisticated performance requirements, the poor dispersibility of polyester fibers becomes apparent as a serious drawback.

The present inventor has developed a polyester polyether polymer consisting of terephthalic acid and/or inphthalic acid, lower alkylene glycol, polyalkylene glycol and/or its monoether. By adding Noku copolymer to the slurry containing polyester fibers, the dispersibility of paper stock slurry containing polyester fibers is improved.
They found that it improved. As a result, it is possible to increase the paper making speed, and it is also possible to make paper with longer fiber lengths, increasing productivity and producing polyester fiber paper or polyester fiber mixed paper with excellent formation and mechanical properties. Now that I can make paper, I am 6.

The polyester polyether block copolymer composed of terephthalic acid and/or inphthalic acid, lower alkylene glycol, and polyalkylene glycol and/or its monoether used in the present invention includes, for example, terephthalic acid-alkylene glycol-polyalkylene glycol, Terephthalic acid-isophthalic acid-alkylene glycol-polyalkylene glycol,
Terephthalic acid - alkylene +) co-#-bo! Examples include block copolymers such as J alkylene glycol monoether and terephthalic acid-isophthalic acid-alkylene glycol-polyalkylene glycol monoether.

Ethylene glycol, propylene glycol, tetramethylene glycol, and pentamethylene glycol are suitable as the alkylene glycol used for producing the block copolymer, and the polyalkylene glycol usually has an average molecular weight of 400 NILOOO, preferably 600. Polyethylene glycol-polypropylene/glycol copolymer and polypropylene glycol are preferred. Further, as the monoether of polyalkylene glycol, monomethyl ether, monoethyl ether, monophenyl ether, etc. of polyethylene glycol, polypropylene glycol, etc. are suitable, but monoethers of polyethylene glycol are particularly preferred from the viewpoint of improving dispersibility. suitable.

Further, the block copolymer has a ratio of terephthalate units to isophthalate units of 95:5 to so:s.

It is particularly preferable that the molar ratio be within the range of terephthalate units: 10 isophthalate ratio: polyalkylene f'J call ratio: 3:
It is preferable for the buttocks to be within the range of 1 to 10:1 <molar ratio) from the viewpoint of the effect of improving dispersibility. Further, the average molecular weight of the block copolymer is generally 1.000 to 20,000, depending on the molecular weight of the polyalkylene glycol used.
Preferably it is λ000 to 10.000. If the average molecular weight is less than 1,000, the effect of improving dispersibility tends to decrease, and if it exceeds 20,000, the dispersion of the block copolymer tends to deteriorate.

The block copolymer can be easily dispersed in water, but in order to further improve the stability of the resulting aqueous dispersion, it is preferable to add a small amount of a surfactant or M solvent.

The polyester polyether block copolymer can be added to the papermaking solution by any method and at any stage, but
In particular, it is suitable to add the block copolymer as an aqueous dispersion. The addition positions are the beater, borcher, mixer box, head box, and pad.

Other pipes or ducts for transporting paper stock slurry may also be used. The amount added is 0.001 to 20% by weight, preferably 0.01 to 10% by weight of the block copolymer based on the fiber.
Weight % is appropriate.

According to the method of the present invention, the dispersibility of polyester fibers is greatly improved, so it is possible to make paper using only polyester fibers, and it is also possible to make paper using polyester fibers alone. It may be mixed with other fibers such as other synthetic fibers such as polypropylene and inorganic fibers such as glass fibers. Note that sticky agents added during paper making have the ability to improve dispersibility to some extent, but according to the method of the present invention, the dispersibility of paper stock slurry is greatly improved, so the help of sticky agents is almost unnecessary. As a result, the sticky agent can be used only for adjusting the C aqueous property, which is very advantageous in terms of process control.

The polyester image line in the present invention is a fiber made of polyethylene tere-7-thalerate, polyethylene terephthalate inphthalate, polybutylene terephthalate, etc., and fibers modified from these, such as basic dye-dyeable polyester, flame-retardant It goes without saying that polyester, antistatic polyester, etc. are included. In addition, the fineness and fiber length are the same as those of ordinary polyester fibers for papermaking, for example, the fineness is 0.01 to 20 deniers,
Preferably it is 0.1 to 10 denier, and the fiber length is 0.1 to 10 denier.
5-25M, preferably 1-20wr.

The method of the present invention has the following features.

(1) Improved dispersion of paper stock during the papermaking process, resulting in better paper formation and increased paper strength. (2) Even in the disintegrating process where the paper stock concentration is high, the dispersibility is good, so density unevenness does not occur. Especially in the chest tank, the paper stock density unevenness is significantly reduced. (3) The paper stock may accumulate in lumps in the slurry stagnation area during the paper making process, or the slurry may adhere like water scale to the walls of the tank or tube.
Problems such as those accidentally getting mixed into the slurry and suddenly disturbing the quality of the paper are drastically reduced. (4) It is possible to increase the paper stock concentration and increase the paper making speed,
Cost reduction t'' can be measured.

The present invention will be explained below with reference to examples, and the dispersibility evaluation method in the examples is as follows.

○Dispersibility evaluation method A water bath solution having a treatment agent concentration of 0.03% by weight (only water in Comparative Example 2) was placed in a 1000-meter graduated cylinder, and 0.1 f of fiber was placed in the water bath solution. When the fibers reach the bottom of the graduated cylinder, cover the graduated cylinder, hold the top and bottom with both hands, turn the graduated cylinder once to disperse the fibers, and count the number of bound fibers contained in the top. At the same time, the quality of the dispersion state is determined from the spread state of each single fiber in water.

◎Very good ○Good ΔIntermediate XBad Examples 1 to 4,
Comparative Examples 1 and 2 Polyethylene terephthalate chips with an intrinsic viscosity of 0.64 dllt were melt-spun using a conventional method, and the single yarn fineness was 1.
．． A 2 denier undrawn yarn was obtained. The undrawn yarn was made into an undrawn tow of 500,000 deniers, drawn at a draw ratio of 2.6 times and a drawing speed of 60 m/min, and heat-treated at 120°C.
The fibers were cut into lengths of 1.5 m to obtain oil-free fibers with a single fiber fineness of 0.54 denier.

Dispersibility was evaluated using this oil-free fiber and various treatment agents shown in Table 1, and the results shown in Table 1 were obtained. still,
The lower alkylene glycols in the block combination 1 of Examples 1 to 3 are all queethylene glycol f.

As is clear from Table 1, according to the method of the present invention,
Compared to conventional methods using surfactants, the dispersibility of polyester fibers is significantly improved.

Patent applicant Teijin Ltd.

Claims (1)

[Claims] (1) When making paper containing polyester fibers, paper is made in the presence of a polyester polyether block copolymer consisting of terephthalic acid and/or inphthalic acid, lower alkylene/glycol, and polyalkylene glycol and/or its monoether. A method for producing polyester fiber-containing paper, characterized by: