JPH0393654A - Cellular glass fiber, its formed body and production thereof - Google Patents

Abstract

PURPOSE:To improve discrimination of moisture absorption degree by dipping cellular glass fiber or a fibrous formed body, such as paper, constructed thereof in a solution of CoCl2 and applying the CoCl2 to the surface of the cellular fiber and inner surfaces of pores thereof. CONSTITUTION:CoCl2 is dissolved in water, ethanol, acetone, etc., to prepare a solution. Cellular glass fiber having about >=200m<2>/g BET specific surface area and about 10-60Angstrom pore diameter or a fibrous formed body in the form of paper, etc., constructed thereof is dipped in the aforementioned solution and treated until bubbles are not produced from the cellular glass fiber while being refluxed at the boiling temperature of the solution. Thereby, the solution is impregnated into pores of the cellular glass fiber. The cellular glass fiber or fibrous formed body thereof is then taken out and dried to provide light blue cellular glass fiber or fibrous formed body thereof having fine crystals of the CoCl2 applied to the surface of the cellular glass fiber and inner surfaces of pores thereof. The CoCl2 is applied to the cellular glass fiber by a means for removing air in the pores of the glass fiber and permeating the solution thereinto at ordinary temperature under reduced pressure as a means for applying the CoCl2 thereto. Thereby, an excellent product is obtained.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to porous glass fibers with excellent moisture absorption performance and molded products thereof, and more specifically to products that can display the degree of moisture absorption by color change. ．． (Prior art) Porous glasses made from phase-separating glasses such as high-Si and high-content sodium borosilicate glasses have been known, and porous glass fibers with a BET surface area of 40 Onf/2 are particularly used as porous glass fibers for dehumidification. g or more, and the pore diameter is 10 to 4
JP-A No. 59-102836 proposes a method in which there are 0 people. (Problems to be Solved by the Invention) The drying ability of the above-mentioned porous glass fibers or paper-like, felt-like, and woven fiber products made using the porous glass fibers decreases due to moisture absorption. However, since there was no change in the appearance of this fiber or fiber molded product, it was not possible to determine whether the performance had decreased.Therefore, when this fiber or fiber molded product is used in a dehumidifier, etc., it is difficult to determine when it will be regenerated or not. It was difficult to know when to replace it.

An object of the present invention is to make it possible to know when it is time to regenerate or replace by expressing the degree of moisture absorption by a change in appearance, that is, a change in color. (Means for Solving the Problem) In order to achieve the above-mentioned object, the present invention is directed to a porous glass fiber or a paper-like fiber molded article made of porous glass fiber. A structure was adopted in which cobalt (II) chloride was attached to the surface and the inner surface of the pores.

In addition, as a means for attaching cobalt (II) chloride, porous glass fibers or paper-like fiber molded bodies made of porous glass fibers are coated with water. ethanol. The fiber pores are removed by immersing the fiber in a solution obtained by dissolving cobalt (II) chloride in acetone or the like and treating it at the boiling point temperature of the solution and under reflux until no bubbles come out from the fiber or fiber molded product. Cobalt (II) chloride is attached to the surface of the porous glass fiber and the inner surface of the pores by impregnating the fiber with a solution, then taking out the fiber or fiber molded body from the solution, and then drying it. This is what I did. In addition, as another means for attaching cobalt chloride (If), a fiber molded article such as a porous glass fiber or a paver cloth made of porous glass fiber is coated with water. The pores of porous glass fibers are impregnated with the solution by dissolving cobalt (n) chloride in ethanol, acetone, etc., and treating this under reduced pressure. Cobalt chloride (I) is attached to the surface of the porous glass fiber and the inner surface of the pores by removing the lath fiber or porous glass fiber molded body from the solution and then drying it. ．． (Function) Fine crystals of cobalt chloride (n) are attached to the surface of the porous glass fiber and the inner surface of the pores. At first, it has a slightly pale blue color, but as the amount of moisture absorbed (water vapor) changes, it gradually changes to blue when the amount of moisture absorbed is low, then to pale red as it increases. (Example) The present invention will be described in detail below. The porous glass fibers used in the present invention may be of any type as long as they have moisture absorption properties; for example,
The pore size is 10 to 60 pores, preferably 10 to 40 pores, and the BET surface area is 200 rrf/g or more, preferably 400 nf/g or more. Then, this porous glass fiber is produced into a porous glass fiber molded article in the form of paper, felt, fabric, etc. by using a binder fiber and appropriate known means. Incidentally, such porous glass fibers and porous glass fiber molded bodies are disclosed in Japanese Patent Application Laid-Open No. 102836/1983, which is referred to as the prior art. The present invention relates to a structure in which cobalt chloride (0) is adhered to the surface and the inner surface of the pores of the porous glass fiber or the porous glass fiber of the fiber molded article.
(II) (11 g of CoC) is a commercially available product and is a blue deliquescent solid. However, the cobalt chloride (I)
The method for attaching I) to the surface of the porous glass fiber and the inner surface of the pores is carried out as follows.

First, a solution is prepared by dissolving an appropriate amount of cobalt (II) chloride in an appropriate amount of water, ethanol, and acetone. Next, a porous glass fiber alone or a porous glass fiber molded article such as paper, felt, or woven material is immersed in this solution, and the porous glass fiber is heated at the boiling point temperature of this solution and under reflux. Process until no bubbles appear. Then, this solution sufficiently penetrates into the fiber pores (impregnation).
do. After that, when the porous glass fiber or fiber molded body is taken out of the solution, the solution adhering to the surface of the porous glass fiber is easily removed by dripping, but most of the solution that has entered the pores of the glass fiber remains inside. I will do it. Next, when the porous glass fiber or fiber molded body is dried by an appropriate means such as heating, the solution on the surface of the glass fiber and in the pores is concentrated, and finally cobalt chloride (II
) are precipitated and adhered to and supported on the fiber surface and the inner surface of the fiber pores. At this time, since the microcrystals have a blue color, the overall appearance of the porous glass fiber and the fiber molded product is pale blue.

Note that the method for adhering cobalt chloride (■) to porous glass, especially the impregnating treatment, was described as a treatment at the boiling point temperature of the solution and under reflux, but instead of this, for example, at room temperature and under reduced pressure. According to this method, the air in the pores of the porous glass fiber is actively removed and the solution sufficiently penetrates into the pores, so that a product with better functionality can be produced.

The porous glass fiber of the present invention or its fiber molded product changes from pale blue to pale red due to an increase in the amount of moisture absorbed. This can be easily done by heating, etc.

(Effect of the invention) The porous glass fiber of the present invention or its fiber molded product has the following properties:
Decrease in drying ability due to moisture absorption can be clearly determined,
Therefore, when used in a dehumidifier, etc., it is convenient because you can easily know when to regenerate or replace it. Further, according to the porous glass fiber or the fiber molded product of the present invention, since cobalt chloride (n) is mainly attached to the inner surface of the pores of the porous glass fiber, it has a strong supporting force and can be easily released. It can be used for a long time without any damage. Furthermore, the manufacturing method is extremely simple and inexpensive.

Claims (4)

[Claims] (1) A porous glass fiber characterized by having cobalt (II) chloride adhered to the surface and inner surface of the pores of the porous glass fiber. (2) A porous material formed by adhering cobalt (II) chloride to the surface of the porous glass fiber and the inner surface of the pores of a paper-like fiber molded article composed of porous glass fiber. Glass fiber molded body. (3) A porous glass fiber or a paper-like fiber molded article made of porous glass fiber is immersed in a solution obtained by dissolving cobalt (II) chloride in water, ethanol, acetone, etc. The solution is impregnated into the pores of the porous glass fiber by treating it at the boiling point temperature of the solution and under reflux until no bubbles come out from the porous glass fiber. By taking out the glass fiber molded body from the solution and then drying it, cobalt chloride (
II) Porous glass fiber and a method for producing a glass fiber molded article. (4) Porous glass fiber or a paper-like fiber molded article made of porous glass fiber is immersed in a solution obtained by dissolving cobalt (II) chloride in water, ethanol, acetone, etc. is treated under reduced pressure to impregnate the pores of the porous glass fiber with a solution, then the porous glass fiber or porous glass fiber molded article is taken out from the solution and then dried to form a porous glass. A porous glass fiber characterized in that cobalt (II) chloride is attached to the surface of the fiber and the inner surface of the pores;
Manufacturing method for glass fiber molded bodies.