Abstract: A cleaning disk is described that is made of a pair of layers of head-cleaning material which are translucent to light produced by a light source in a magnetic disk-reading machine. The layers are adhered with an adhesive having sufficient opacity caused by the addition of pigment to reduce the light transmitted through the layers from the light source enough to prevent sensing of the light by the corresponding light sensor. Fibers of the layers, when made of fabric, may extend through the adhesive to provide for permeation of a solvent from one layer to the other. The layers are preferably adhered by heat plastified thermoplastic polymeric adhesive which is compressed between non-heat-plastified layers and which is formed to have solvent-transmitting holes extending through it.

Abstract: A card is provided for cleaning transducer heads of magnetically-encoded card reading machines. The card includes a surface region disposed for contacting such a transducer head and releasably holds a head cleaning solvent adjacent the surface region. The material forming the surface region may be visually distinguishable when it is holding solvent as compared to when it is not. Further, this material may be translucent when holding solvent. If so, the material immediately next to the solvent-holding material is a color which is visible through the material. Also, the card may have layers which are joined by heat-bonding. The side of the card opposite from the surface region then preferably is another color.