Abstract: Correction compositions for the masking of erroneous typed images preliminary to the typing of correct images thereover, characterized by the presence of a volatile solvent mixture having a predetermined evaporation rate at ordinary room temperatures, a high flash point and providing vapors which are non-flammable and non-toxic as a result of drying of the compositions under normal office conditions. The solvent mixtures used according to the present invention comprise methyl chloroform and perchlorethylene.

Abstract: Pressure-sensitive reusable transfer elements of the squeeze-out type having a microporous resinous ink-releasing layer firmly bonded to a flexible foundation. The invention is characterized by the use of a bonding layer which is applied to the foundation as an aqueous composition comprising a water-dispersible, water-insoluble resinous binder material which dries to form a tacky, adhesive layer.

Abstract: Pressure-sensitive master sheets are produced by printing ink-releasing images onto a master sheet by silk screen techniques using a semi-solid printable ink composition comprising a wax and/or resin binder material, an incompatible oleaginous material, colorant and a volatile vehicle. The solidifed printed images comprise a porous, spongy network of the binder material containing within the pores thereof the oleaginous material and colorant as a pressure-exudable ink. The printed master is suitable for the production of several copies in a dry pressure-copying process.

Abstract: A novel inking method and apparatus particularly well suited for the re-inking of used fabric ribbons such as of the chain-printer type. The apparatus preferably contains means for moving a fabric ribbon through an inking station onto a take-up roll, means in advance of the inking station for adjusting the edge-alignment of the ribbon, embossed or gravure inking means for supplying ink directly to the ribbon without compression of the ribbon, illumination means to facilitate the inspection of the ribbon for flaws and for uniformity of ink, and shut-off means for stopping the movement of the ribbon at any desired position.

Abstract: Pressure-sensitive transfer elements comprising water-applied resinous base coating supporting a resinous ink-releasing layer, characterized by the undercoating consisting essentially of a water-dispersible, water-insoluble hydrophilic polyurethane resin.

Abstract: Novel thixotropic hectograph printing ink and process for printing hectograph master sheets or transfer sheets therewith comprising preparing a semi-solid, thixotropic hectograph printing ink containing non-drying semi-solid oleaginous material, film-forming binder material at least partially dissolved in a relatively high boiling organic solvent having dispersed therein hectograph dyestuff and finely-divided fusible, waxy particles, printing the hectograph composition in image form onto a master sheet or as a continuous or spot layer on a foundation and heating such as by means of infrared radiation to heat the composition to a temperature above the melting point of the waxy particles to fuse the composition and render it smooth, smear-resistant and stable.

Abstract: Process for producing multicolor pressure-sensitive transfer elements comprising the steps of preparing a thin microporous resinous layer, impregnating a preselected partial area thereof with a liquid non-drying ink of one color and impregnating another adjacent preselected partial area thereof with another liquid non-drying ink of a different color, an ink barrier preferably being provided between said areas to prevent integration of said different colored inks.

Abstract: A split correction-imaging ribbon comprising a longitudinal strip of film-base adhesive correction composition and an adjacent longitudinal strip of film-base pressure-transferable imaging composition. The two strips are overlapped and bonded together by means of the adhesive correction composition to provide a unitary element such as a typewriter ribbon which is bifunctional, i.e. capable of producing typed images on a copy sheet and also capable of removing such typed images as may be erroneous.

Abstract: Process of producing novel reusable pressure-sensitive transfer elements comprising a microporous resinous network of synthetic thermoplastic resin having formed therein a pressure-exudable fluid ink containing a polymerizable resin-forming material. The resin-forming material is stable within the transfer element under ambient conditions but is capable of being exuded to a copy sheet, as an ingredient of said ink, to form images which can be cured by subjecting them to polymerization conditions.

Abstract: A continuous ink-transfer printing system employing a hot-melt wax imaging composition supported on a strong pressure-conforming plastic film web which is continuously recoated with fresh imaging composition to replace imaging composition which is imagewise transferred at a pressure-imaging station. The system comprises an ink-coating station, a pressure-imaging station and an ink-melting station associated with the ink-coating station.

Abstract: Ink-supply system for duplicating machines such as typewriters to alleviate the necessity for using conventional ribbons. System comprises a thin film strip or band which has an affinity for liquid ribbon ink, and an inking means for continuously supplying a thin continuous layer of liquid ink to the surface of said film.

Abstract: Pressure-sensitive transfer sheets and ribbons having a flexible plastic foundation carrying a colored layer comprising pressure-transferable imaging material, the plastic foundation consisting of a laminate of two different plastic films, one of which is stronger and less deformable than the other.