The ornamental design for paper for envelope, as shown and described.
FIG. 1 is a front view of paper for envelope;
FIG. 2 is a rear view thereof;
FIG. 3 is a right side view thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is an enlarged view taken at the portion 5 of FIG. 1 showing a hole and other parts at the corner;
FIG. 6 is a front view of paper for envelope showing the second embodiment of my new design;
FIG. 7 is a rear view thereof;
FIG. 8 is a right side view thereof;
FIG. 9 is a top plan view thereof; and,
FIG. 10 is an enlarged view taken at the portion 10 of FIG. 6.
The broken lines showing on the drawing disclosure are for showing unclaimed subject matter and form no part of the claimed design. The dot-dash lines indicate conceptual border lines between the claimed portions and the disclaimed portion.