US1879443A - Protective paper strips for daylight loading film rolls - Google Patents

Description

Sept. 27, 1932. E. OPFERMANN ET AL 1,379,443

PROTECTIVE PAPER STRIPS FOR DAYLIGHT LOADING FILI ROLLS Filed Oct. 8, 1930 0/) afparr/imebfll'edpapel' (e/lwbs/c av/ aar/ I By Afforn y Patented Sept. 27, 1932 UNITED STATES PATENT OFFICE ERICH OPFERMANN, 0F IBERLIN-CHARLOTTENBURG, AND WALTER FISCHER, OF DESSAU IN ANHALT, GERMANY, ASSIGNORS TO AGFA ANSCO CORPORATION, OF BINGILAMTON, NEW YORK, A CORPORATION OF NEW YORK PROTECTIVE PAPER STRIPS FOR DAYLIGHT LOADING. FILM ROLLS Application filed October 8, 1930, Serial No. 487,372, and in Germany October 25, 1929.

Our present invention relates to photographic film rolls and more particularly to such film bands provided on both ends with a paper strip impermeable to light rays.

The usual film rolls for daylight loading consist of a film band wound on a spool, the film being provided, for protecting it against the entry of light, with so-called allonges, i. e., strips of paper impermeable to daylight attached to both ends of the film. As it appears desirable to make these protective paper strips nearly as stiff as the film, in order to ensure a smooth forwarding of the hand through the apparatus, attempts have been made to stiffen the paper by coating it with layers of gelatin or cellulose derivatives. Moreover, it has been proposed for the manufacture of the protective paper strip, to superpose two paper strips and to unite them by means of an intermediate layer of a water-proof agglutinant.

According to our invention, protective paper strips having the stiffness required, are made in a simple manner without application of special strengthening layers by preparing the strip from a parchmentized paper colored in the usual way so as to be lighttight.

The paper may be parchmentized in the usual manner, for instance, by short immersion in strong sulfuric acid and quickly washj,

ing it. Unsized and sized paper may be used and, if desired, also paper consisting of several layers couched one over the other. When using sized paper, this is only parchmentized on its surface. It is also possible to unite a sheet of black and a sheet of red paper by parchmentizing them or to parchmentize two paper strips separately, to wash them and then to couch them, while in a moist state, one on the other.

As compared with the protective paper strips hitherto used, those made of parchmentized paper have not only the advantage of possessing a greater stiffness and tenacity but also ensure in consequence of the pores being closed by the parchmentizing process an enhanced protection against light; furthermore they are more grease-proof and more water-proof. They, therefore, protect the film against loss of moisture during prolonged storage and delay its drying out which is apt to cause brittleness.

If desired, the parchmentized protective paper strips may be subjected to mechanical glazing. Moreover, for reducing friction they may be coated in known manner with Wax, gelatin or the like. Generally, the paper strips are colored in the known manner with dyes absorbing the active light rays.

In the accompanying drawing Fig. 1 and Fig. 2 illustrate our invention.

Fig. 1 is a perspective view of a fragment of the film strip showing the junction of the sensitized portion and the strip of parchmentized paper, the thickness being much exaggerated.

Fig. 2 is a plan of a fragment of the film strip showing the junction of the sensitized and protective bands.

What we claim is Film rolls for daylight loading comprising a film band provided at both ends with a protective stri of parchmentized paper impermeable to light having about the same stiflness as the film band.

In testimony whereof, we affix our signatures.

ERICH OPFERMANN. WALTER FISCHER.

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