3M DECtape Spec Nov66

This document provides technical data for Scotch Magnetic Tapes models 480 and 481, designed for instrumentation, as of November 1966.

Both tapes are made of Black/Brown Polyester and are nearly identical in their width tolerance, shock tensile strength, coating wearability, layer-to-layer adhesion, and all listed intrinsic magnetic and electromagnetic performance properties (including coercivity, retentivity, maximum undistorted output, sensitivity, uniformity, and dropouts).

The primary distinction lies in their physical construction and associated mechanical strength:

• Tape 480 is thicker (1.85 mils total) compared to Tape 481 (1.35 mils total), primarily due to its backing material.
• Consequently, Tape 480 exhibits superior static tensile strengths (higher yield, breaking strength, and elongation at break) and less residual elongation (0.1% for 480 vs. 0.2% for 481), indicating greater physical robustness and less permanent deformation after stress.

The document includes detailed "Test Notes" explaining the measurement methodologies for each property. A "Terms and Conditions of Sale" section clarifies that the provided data is believed reliable but not guaranteed, limiting the manufacturer's liability to product replacement and placing the responsibility for product suitability and associated risks on the user. The data is typical and intended for comparative purposes.