The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 09, 1989
Filed:
Jun. 26, 1987
Mutsuo Akao, Kanagawa, JP;
Kenji Tajima, Kanagawa, JP;
Fuji Photo Film Co., Ltd., Minami-Ashigara, JP;
Abstract
In a packaging case for photosensitive sheet film comprising a light-shielding tray which receives a stack of said photosensitive sheet films and a light-shielding flexible cover sheet which is stuck in peelable state to seal the opening for taking out said stack, the improvement comprising that said tray is made of resin comprising 50 to 90 wt. % of a propylene-.alpha.-olefin copolymer resin having a melt index of higher than 18 g/10 minutes, a bending elastic modulus of more than 9,000 kg/cm.sup.2 and a notched Izod impact strength of more than 2.0 kg cm/cm at 23.degree. C., 0.2 to 5.0 wt. % of carbon black and 9.8 to 49.8 wt. % of linear low density polyethylene resin. In the light-shielding tray of the invention, rigidity is secured by the propylene-.alpha.-olefin copolymer resin, and troubles caused by this copolymer resin such as mold shrinkage, warp and twist of the product are overcome and remarkable lowering of physical strength by blending carbon black are attained by incorporating the L-LDPE resin. Accordingly, even when this tray is made thin, sufficient rigidity and physical strength can be secured, although the tray is large. Since the deformation is small sealability between the light-shielding flexible cover sheet is acceptable. Moldability of the resin composing the tray is also sufficient.