JP2916651B2 - Paper with water repellency and resistance to hydrous alcohol - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to paper having excellent water repellency, resistance to hydrous alcohol, and having the texture of ordinary paper.

Conventional technology and its problems Conventionally, wax, fatty acid derivatives, synthetic resins, organic silicon derivatives, and the like have been used to impart water repellency to paper. In such a water-repellent paper to which a water-repellent agent has been added, the texture and characteristics of ordinary paper are often lost due to changes in the feel of the paper and changes in the appearance due to reflected light. Therefore, for example, when such water-repellent paper is placed on top of another,
There are various problems in processing. In addition, when an organic silicon derivative-based water repellent is used, there is a lack of resistance to water-containing alcohol (water-resistant alcohol resistance). there were.

Means for solving the problems The present inventor has conducted research in view of the current state of such technology, and as a result, when using at least one of pitch fluoride and heat-treated pitch fluoride as a water repellent, It has been found that a paper having excellent properties such as water repellency and resistance to hydrous alcohol and having little change in texture as paper can be obtained.

That is, the present invention provides "paper having water repellency and resistance to hydrous alcohol, comprising at least one of pitch fluoride and heat-treated pitch fluoride".

The fluorinated pitch used as a water repellent in the present invention can be produced, for example, by the method described in JP-A-62-275190.
It can be obtained by directly fluorinating with a fluorine gas at about the temperature. This pitch fluoride has a composition formula CF _x (0.5 <
x <1.8), and its color is brown to yellowish white to white, excellent in water resistance, chemical resistance to alcohols, acids, non-fluorinated organic solvents, etc., and very stable in air. I have. Further, in the present invention, the above properties are further improved by using such a pitch fluoride that has been further heat-treated at about 150 to 310 ° C. for about 5 minutes to about 10 hours in a fluorine atmosphere. The solubility in the following fluorine-based solvents can be improved.

In producing the water-repellent paper of the present invention, the above-mentioned pitch fluoride and / or heat-treated pitch fluoride (hereinafter, simply referred to as pitch fluoride unless otherwise required) is dissolved in a fluorine-based solvent and obtained. Treat the paper with the solution.

The fluorine-based solvent is not particularly limited as long as it can dissolve pitch fluoride, but is usually hexafluorobenzene, perfluoromethylcyclohexane, perfluorodimethylcyclohexane, perfluorodecalin, perfluorophenanthrene, Chloropentafluorobenzene, perfluorotributylamine and the like are used. In the case of heat-treated fluorinated pitch, 1,1,2
Freons such as trichloro-1,2,2-trifluoroethane, dibromotetrafluoroethane, dichlorodifluoromethane, dichloropentafluoropropane can also be used as the solvent. That is, in the case of heat-treated fluorinated pitch, the types of applicable solvents are increased.

The concentration of the pitch fluoride in the solution may be appropriately selected depending on the water repellency required for the paper, the treatment method of the paper, the solvent dissolving ability, and the like, and is usually about 2 to 10% by weight.

The treatment of the paper is performed by any method such as a method of spraying the pitch fluoride solution on the paper, a method of dipping the paper in the pitch fluoride solution, and a method of applying the pitch fluoride solution to the paper. Can be.

The amount of the fluorinated pitch applied to the paper is sufficient to be about 5% of the dry weight of the paper, usually about 0.2 to 2%. If the amount of the pitch fluoride is excessive, the texture of the paper may be impaired.

Effects of the Invention According to the present invention, the following remarkable effects are achieved.

(1) The paper according to the present invention hardly differs from the paper before processing in terms of feel and appearance.

(2) The paper according to the present invention is excellent in water repellency and resistance to hydrous alcohol.

(3) Further, since the paper according to the present invention has an affinity for organic solvents other than alcohols, the paper can be used for separating an organic solvent from a water-organic solvent-based mixture by utilizing the selective filtration action of the organic solvent. Can be used.

(4) The water-repellent paper of the present invention having characteristics different from those of the conventional water-repellent paper as described above can be used in a wide range of fields.

EXAMPLES Examples are shown below to further clarify features of the present invention.

Example 1 (a) Production of fluorinated pitch: softening point 100 ° C., quinoline insoluble content 0.2%, benzene insoluble content
Add twice the amount of hydrogenated anthracene oil to 30% coal tar pitch, heat at 430 ° C for 90 minutes, and further reduce pressure to 300 ° C
To remove the hydrogenated anthracene oil to obtain a reduced pitch.

Next, nitrogen gas is introduced into the obtained reduced pitch,
The low molecular weight components were removed, and thermal polymerization was carried out at 400 ° C for 5 hours. The softening point was 300 ° C, the quinoline insoluble content was 60%, and the benzene insoluble content was 98.
%, And a mesophase pitch having a mesophase content of 90% or more was obtained.

50 g of the obtained mesophase pitch was charged into a nickel reaction vessel, the system was evacuated, and then filled with argon gas. Next, the reaction was carried out for 20 hours at 70 ° C. by flowing a fluorine-containing gas (mixed gas of 20% fluorine + 80% argon) at a rate of 650 cc / min at 70 ° C.
4 g of pitch fluoride were obtained.

As a result of the elemental analysis, the composition formula of the obtained pitch fluoride is
It was CF _1.39 .

The pitch fluoride thus obtained was heat-treated at 250 ° C. for 5 hours in a fluorine atmosphere.

(B) Production of water-repellent paper: heat-treated pitch obtained above was dissolved in 1,1,2-trichloro-1,2,2-trifluoroethane,
A 5% by weight solution was obtained. Next, filter paper, woodfree paper, creped paper and Japanese paper whose weight had been measured in advance were immersed in these solutions, air-dried, and then weighed to determine the amount of fluorinated pitch deposited.

The water repellency of each paper before and after the treatment was measured by JIS P8137 “Water repellency test method”. Further, for comparison, the water repellency of a commercially available separation filter paper was measured in the same manner.

 The results are as shown in Table 1.

The evaluation of the water repellency in the present example and each of the following examples was performed by dropping a 0.1 cc water drop from a 1 cm upper portion on a paper inclined at 45 degrees with a burette, according to the following criteria.

* R ₀ : A continuous trace showing a uniform width.

* R ₂ ... a continuous trace than water droplets show a slightly narrower width.

* R ₄ … a continuous trace, but cut off in places, clearly showing a width slightly smaller than a water drop.

* R ₆ ... Half of the trace is wet.

* R ₇ … 1/4 of the trace is wet by long and long drops of water.

* R ₈ … More than 1/4 of the traces are scattered with small spherical water droplets.

＊ R ₉ … Small spherical water droplets are scattered.

* R ₁₀ ... water droplets roll down completely.

Example 2 In a mixed solvent of hexafluorobenzene: dichlorodifluoromethane = 1: 1, a fluorinated pitch manufactured in the same manner as in Example 1 (however, the obtained fluorinated pitch was not heat-treated) was dissolved. Thus, a solution of 0.5 to 5% by weight was prepared, and this solution was sprayed on the filter paper through a nozzle.

As a result, water repellency in impregnation amount of 0.5 to 5 wt%, was R _9.

Example 3 Fluoride pitch impregnated filter paper (pitch fluoride impregnation amount 2 to 2) manufactured by the same method as in Example 1 (heat treatment was also performed)
3% by weight) using methanol and methanol-
The water repellency against the methanol mixture was measured.

The results are as shown in Table 2. Table 2 also shows the results for commercially available filtrates.

Example 4 A mixed solution of hexane: water = 1: 1 was filtered using the pitch-fluorinated pitch impregnated filter paper obtained in Example 1.

As a result, regardless of the amount of pitch fluoride impregnation, only hexane was separated by filtration, and water remained on the filter paper.

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Mikio Sasabe 1-19-15-2407, Shibuya, Shibuya-ku, Tokyo (58) Field surveyed (Int. Cl. ⁶ , DB name) D21H 1/34, 27/00

Claims (1)

(57) [Claims] 1. A paper having water repellency and resistance to hydrous alcohol, comprising at least one of pitch fluoride and heat-treated pitch fluoride.