Mitsubishi Rayon Company, Limited

Mitsubishi Chemical Corporation

Hitoshi Tomobe

Nobuyuki Yamamoto

Atsushi Kawamura

Satoshi Kaji

Hirotoshi Mizota

Tomonari Murakami

Hajime Okutsu

Daisuke Morimoto

To perform a flame-resistant treatment on a precursor fiber strand by sending hot air to a heat treatment chamber () through a hot air blowing nozzle () in a direction parallel to a running direction of a precursor fiber strand (). The hot air blowing from the hot air blowing nozzle () passes through a porous plate and a rectifying member that satisfy the following conditions (1) to (4), wherein the conditions are set as follows: (1) A/B&#x2267;4.0; (2) 0.15&#x2266;&#x3b1;&#x2266;0.35; (3) 0&#x2266;B&#x2212;d&#x2266;20; and (4) 80% or more of an area of one opening of the porous plate when causing facing surfaces of the porous plate and the rectifying member to overlap each other is included in one opening of the rectifying member, A indicating a hot air passage distance (mm) of the rectifying member, B indicating a horizontal maximum distance (mm) of one opening of the rectifying member, &#x3b1; indicating a rate of hole area of the porous plate, and d indicating an equivalent diameter (mm) of the porous plate. Accordingly, it is possible to provide a parallel stream type flame-resistant heat treatment furnace having exhibiting the uniform heat transfer performance throughout the inside of the heat treatment chamber by preventing the blockage of the nozzle caused by a silicone compound generated inside the heat treatment chamber even in the hot air blowing nozzle having a simple structure.

Flame-resistant heat treatment furnace

A furnace to flame-resistantly treat a precursor fiber strand by sending hot air to a heat treatment chamber through a hot air blowing nozzle in a direction parallel to a running direction of the strand is provided. The hot air passes through a porous plate and a rectifying member satisfying the following conditions: (1) A/B&#x2267;4.0; (2) 0.15&#x2266;&#x3b1;&#x2266;0.35; (3) 0&#x2266;B&#x2212;d&#x2266;20; and (4) 80% or more of the area of one opening of the porous plate when facing surfaces of the porous plate and the rectifying member overlap is included in one opening of the rectifying member, where A is the rectifying member hot air passage distance (mm), B is a horizontal maximum distance (mm) of one opening of the rectifying member, &#x3b1; is a rate of hole area of the porous plate, and d is the porous plate equivalent diameter (mm).

To be provided are a heat treatment apparatus having blocking members which block gaps between the side walls of nozzle boxes provided with slit nozzles, whose size in the lengthwise direction is greater than the width of a sheet, and the side walls of a heat treatment chamber, and gas having a uniform velocity fluctuating no more than &#xb1;25% in the lengthwise direction of the slit nozzles is blown out of the slit nozzles to subject the sheet to heat treatment, resulting in little unevenness of temperature in the widthwise direction and reduced energy loss, and a heat treatment method using this heat treatment apparatus.

Heat treating apparatus and heat treating method for sheet-like article

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Hiroshima, Japan

Hitoshi Tomobe