Porous liquid absorbing-and-holding member, process for production thereof, and alcohol absorbing-and-holding member

Abstract

An object of the present invention is to provide a porous liquid absorbing-and-holding member having a high absorbing capacity for a liquid owing to capillarity and having in itself a structure capable of holding a large amount of the liquid, a process for producing this member, and a member for absorbing and holding an alcohol used as a fuel for a fuel cell. The porous liquid absorbing-and-holding member provided by the present invention is that including a porous sintered product having a skeleton formed by sintering of metal powder around voids and subjected to hydrophilicity-imparting treatment. The hydrophilicity-imparting treatment is preferably the formation of one or more substances selected from the group consisting of silicon oxides, titanium oxides, chromium oxides and aluminum oxide on the skeleton.

1 - 4 . (canceled) 
   
   
       5 . A process for producing a porous liquid absorbing-and-holding member which comprises a porous sintered product having a skeleton formed by sintering of metal powder around voids and subjected to hydrophilicity-imparting treatment, wherein the whole porous sintered product has a porosity content of not more than 95% by volume and not less than 60% by volume, and the hydrophilicity-imparting treatment is the coating of one or more substances selected from the group consisting of silicon oxides and titanium oxides on the surface of the skeleton, the process comprising:
 preparing a molded product mixed with the metal powder, a binder and particles which have been added for assuring void size, which particles are soluble in a solvent,   removing said particles from said molded product by the use of the solvent,   sintering said product after removal of said particles, and subjecting said sintered product to the hydrophilicity-imparting treatment for coating said substances.   
   
   
       6 - 10 . (canceled) 
   
   
       11 . A process according to  claim 5 , wherein the hydrophilicity-imparting treatment is the coating of the silicon oxides. 
   
   
       12 . A process according to  claim 5 , wherein the skeleton has pores with an average pore size of 5 to 100 μm, the average void size is 100 to 2,000 μm, and the porosity content of the whole porous material is not more than 90% by volume and not less than 70% by volume. 
   
   
       13 . A process for producing a porous liquid absorbing-and-holding member comprising a porous sintered product having a skeleton formed by sintering of metal powder around voids and subjected to hydrophilicity-imparting treatment, wherein the whole porous sintered product has a porosity content of not more than 95% by volume and not less than 60% by volume, and the hydrophilicity-imparting treatment is the coating of one or more substances selected from the group consisting of silicon oxides and titanium oxides on the skeleton, the process comprising:
 preparing a molded product mixed with the metal powder, a binder and resin particles which have been added for assuring void size,   removing said resin particles from said molded product,   sintering said product after removal of said resin particles, and   subjecting said sintered product to the hydrophilicity-imparting treatment for coating said substances.   
   
   
       14 . A process according to  claim 13 , wherein the hydrophilicity-imparting treatment is the coating of the silicon oxides. 
   
   
       15 . A process according to  claim 13 , wherein the skeleton has pores with an average pore size of 5 to 100 μm, the average void size is 100 to 2,000 μm, and the porosity content of the whole porous material is not more than 90% by volume and not less than 70% by volume.