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Oxygen indicator adapted for printing or coating and oxygen-indicating device

  • US 4,349,509 A
  • Filed: 06/27/1980
  • Issued: 09/14/1982
  • Est. Priority Date: 07/03/1979
  • Status: Expired due to Term
First Claim
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1. An oxygen indicator adapted for printing which comprises(a) at least one reducing agent selected from the group consisting of mixtures of at least one alkaline substance and dithionites, ferrous compounds, reducing saccharides or mixtures thereof;

  • ascorbic acid;

    erysorbic acid or a salt thereof;

    stannous salts;

    hydroxyamine;

    hydrazine;

    keto-carboxylic acids;

    sulfoxylates;

    alkali metal sulfides and boron hydrides;

    (b) a dyestuff which has a color in an atmosphere containing oxygen and a different color in a non-oxygen containing atmosphere when it is reduced with said reducing agent;

    (c) at least one thickening agent selected from the group consisting of sodium carboxymethyl cellulose, hydroxyethyl cellulose, methyl-cellulose, sodium alginate, polyvinyl alcohol, gum arabic powder, gum tragacanth, dextrin and casein in an amount of 0.05-10% by weight on the basis of (a), (b), (c) and (d); and

    (d) at least one solvent selected from the group consisting of water, alcohols, and mixtures thereof.

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