Patent Number: 054019710
Section: description

EXAMPLES 1-3 AND COMPARATIVE EXAMPLES 1-2 Image storage panels were prepared from BaFBr.sub.0.80 I.sub.0.20 :0.001Eu.sup.2+ storage phosphor as above described. PVF.sub.2 /PMMA blend overcoat layers were prepared with the blend ratios and thicknesses indicated in Table 1. PSL results were determined as discussed above and are presented in Table 1 along with relative stability values, normalized to a nominal thickness of 1. EXAMPLES 4-12 AND COMPARATIVE EXAMPLES 3-4 Overcoat layer solutions were prepared in the same manner as in Example 1 and were knife-coated onto tempered metal blocks at 10.degree. C. Each overcoat layer was scratched with a finger nail and various hardnesses of pencil. Results are presented in Table 2. EXAMPLE 13 An overcoat layer was prepared in the same manner as Examples 4-12, with the exception that poly(ethylmethacrylate) was substituted for poly(methylmethacrylate). The overcoat layer was clear and did not scratch with a finger nail. COMPARATIVE EXAMPLE 5 Attempts were made to prepare overcoat layers using vinylidene fluoride-hexa fluoropropylene copolymer instead of vinylidene fluoride-tetrafluoroethylene copolymer in the same manner as in Example 1. Overcoat layers prepared were cloudy. EXAMPLE 14 An overcoat layer was prepared in the same manner as in Examples 4-12, with poly(methyl methacrylate) and with a 50/50 blend of vinylidene fluoride-co-tetrafluoroethylene copolymer and poly(methyl methacrylate). The blended polymer overcoat gave less curl than the poly(methyl methacrylate) alone. TABLE 1 ______________________________________ Blend Example or Ratio Comparative PVF.sub.2 to Overcoat PSL % of Relative Example PMMA Thickness Initial Stability ______________________________________ Comparative 100/0 6.0 39 6.5 Example 1 Example 1 70/30 8.8 39 4.4 Example 2 60/40 7.6 42 5.5 Example 3 50/50 8.4 20 2.4 Comparative 0/100 8.4 8 0.9 Example 2 ______________________________________ TABLE 2 ______________________________________ Example Blend Visible Visible Visible Visible or Comp. Ratio PVF.sub.2 Marks Marks Marks Marks Example to PMMA Nail HB 2H 3H ______________________________________ Com Ex 3 100/0 Yes Yes Yes Yes Ex 4 90/10 Yes Yes Yes Yes Ex 5 80/20 No Yes Yes Yes Ex 6 70/30 No No Yes Yes Ex 7 60/40 No No No Yes Ex 8 50/50 No No No No Ex 9 40/60 No No No No Ex 10 30/70 No No No No Ex 11 20/80 No No No No Ex 12 10/90 No No No No Com Ex 4 0/100 No No No No ______________________________________ While specific embodiments of the invention have been shown and described herein for purposes of illustration, the protection afforded by any patent which may issue upon this application is not strictly limited to a disclosed embodiment; but rather extends to all modifications and arrangements which fall fairly within the scope of the claims which are appended hereto: