(US5726105-A)      Mfr. of a graphitised composite article, comprises (i) forming a uncured composite article of carbon fibre felt embedded within a matrix of a carbon filler, a thermosetting resin and a solvent, (ii) removing the solvent from the uncured article; (iii) applying pressure and heat to the uncured article to produce a cured compressed composite article; (iv) heating the cured article to a first temp. to produce a carbonised composite article, where the fibres, the filler and the resin are carbonised; and (v) heating the carbonised composite article to a second temp. higher than the first temp. to produce the composite article. The graphitised composite article is impermeable to gases and liquids.    Also claimed is a method as specified above but where step (iii) is carried out in two stages namely (iiia) applying heat and pressure to the uncured article to produce an uncured compressed article and (iiib) applying heat and pressure to the uncured compressed article to produce a cured compressed article.    Also claimed is a graphitised composite article made by the above method.    Also claimed is a graphitised composite article, which comprises graphitised carbon fibres, a graphitised carbon filler and a graphitised resin char, such that the article is impermeable to gases and liquids.    USE -   The graphitised laminate can be used as a separator plate for a fuel cell.    ADVANTAGE -   The separator plate prevents permeability of reactants for up to and exceeding 40,000 hours. There is additionally improved prod. reliability, reduced sensitivity to isolated defects within a single composite article when a laminate is formed of several composite articles, significantly increased yield due to the redn. of warping problems    (JP10502214-W)      Mfr. of a graphitised composite article, comprises (i) forming a uncured composite article of carbon fibre felt embedded within a matrix of a carbon filler, a thermosetting resin and a solvent, (ii) removing the solvent from the uncured article; (iii) applying pressure and heat to the uncured article to produce a cured compressed composite article; (iv) heating the cured article to a first temp. to produce a carbonised composite article, where the fibres, the filler and the resin are carbonised; and (v) heating the carbonised composite article to a second temp. higher than the first temp. to produce the composite article. The graphitised composite article is impermeable to gases and liquids.    Also claimed is a method as specified above but where step (iii) is carried out in two stages namely (iiia) applying heat and pressure to the uncured article to produce an uncured compressed article and (iiib) applying heat and pressure to the uncured compressed article to produce a cured compressed article.    Also claimed is a graphitised composite article made by the above method.    Also claimed is a graphitised composite article, which comprises graphitised carbon fibres, a graphitised carbon filler and a graphitised resin char, such that the article is impermeable to gases and liquids.    USE -   The graphitised laminate can be used as a separator plate for a fuel cell.    ADVANTAGE -   The separator plate prevents permeability of reactants for up to and exceeding 40,000 hours. There is additionally improved prod. reliability, reduced sensitivity to isolated defects within a single composite article when a laminate is formed of several composite articles, significantly increased yield due to the redn. of warping problems    (US6039823-A)      Mfr. of a graphitised composite article, comprises (i) forming a uncured composite article of carbon fibre felt embedded within a matrix of a carbon filler, a thermosetting resin and a solvent, (ii) removing the solvent from the uncured article; (iii) applying pressure and heat to the uncured article to produce a cured compressed composite article; (iv) heating the cured article to a first temp. to produce a carbonised composite article, where the fibres, the filler and the resin are carbonised; and (v) heating the carbonised composite article to a second temp. higher than the first temp. to produce the composite article. The graphitised composite article is impermeable to gases and liquids.    Also claimed is a method as specified above but where step (iii) is carried out in two stages namely (iiia) applying heat and pressure to the uncured article to produce an uncured compressed article and (iiib) applying heat and pressure to the uncured compressed article to produce a cured compressed article.    Also claimed is a graphitised composite article made by the above method.    Also claimed is a graphitised composite article, which comprises graphitised carbon fibres, a graphitised carbon filler and a graphitised resin char, such that the article is impermeable to gases and liquids.    USE -   The graphitised laminate can be used as a separator plate for a fuel cell.    ADVANTAGE -   The separator plate prevents permeability of reactants for up to and exceeding 40,000 hours. There is additionally improved prod. reliability, reduced sensitivity to isolated defects within a single composite article when a laminate is formed of several composite articles, significantly increased yield due to the redn. of warping problems