Fluorescent marking liquid
AssigneeFaber-Castell AG
InventorRudolf Stengel
Life of this patent
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Abstract
A new fluorescent aqueous marking liquid is described, which contains 0.20 to 2.0 % by weight of cumarin C.J. Basic Yellow 40 dye. The liquid is buffered to a pH value of from 3 to 5; it contains an acrylic resin dispersion at a pH of 3 to 5 with a particle agglomerate of 35 to 150 nm. The liquid does not act on a third dye, especially triphenylmethane dye, which is used frequently in carbon paper and is used also on smooth surfaces such as glass plastic foil or glazing paper.
Claims14
A fluorescent aqueous marking liquid containing
- a cumarin C.J. Basic Yellow 40 dye,
- an acrylic resin, and
- an aqueous buffer;
- said marking liquid being adjusted to a pH value of from 3 to 5, and said acrylic resin being present in a plurality of dispersed particle agglomerates so as to form a stable dispersion at said pH.
A marking liquid according to claim 7, wherein said polyfunctional alcohol is present in an amount of up to 10 % by weight.
A fluorescent aqueous marking liquid for cohesive marking of a glass surface, a plastic foil surface, a paper surface or a glazing paper surface, said marking liquid containing:
- a cumarin C.J. Basic Yellow 40 dye,
- triphenylmethane dye,
- an acrylic resin, and
- an aqueous buffer;
- said marking liquid being adjusted to a pH value of from 3 to 5, and said acrylic resin being present in a plurality of dispersed particle agglomerates so as to form a stable dispersion at said pH.
Dependencies are inferred from the claim text.