1、r 1 -_ EIA 339 b 3234600 00b5700 L fl b 1- Recommended Tes USAS C83.35-1968 Approved July 24, 1968 USA STANDARDS INSTITUTE EIA STANDARD Method - Layer-to-Layer A d hesion Magnetic Tape of RS=339 November 1967 Engneering Department ELECTRONIC INDUSTRIES ASSOCiATiON EIA 339 67 = 3234600 0065701 3 = NO
2、TICE EIA engineering standards are designed to serve the public interest through eliminating mis- understandings between manufacturers and purchasers, facilitating interchangeability and improve- ment of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper p
3、roduct for his particular need. Existence of such standards shall not in any respect pre- clude any member or non-member of EIA from manufacturing or selling products not conforming to such standards, nor shall the existence of such standards preclude their voluntary use by those other than EIA memb
4、ers whether the standard is to be used either domestically or internationally. Recommended standards are adopted by EIA without regard to whether or not their adoption may involve patents on articles, materials, or processes. By such action, EIA does not assume any liability to any patent owner, nor
5、 does it assume any obligation whatever to parties adopting the recommended standards. Published by ELECTRONIC INDUSTRIES ASSOCIATION Engineering Department 2001 Eye Street, N. W., Washington, D. C. 20006 0 Electronic Industries Association U67 AU rights resewed Price f.60 Printed in U.S.A. EIA 339
6、67 m 3234600 0065702 5 m 1 RS-339 Page 1 RECOMMENDED TEST METHOD - LAYER-TO-LAYER ADHESION OF MAGNETIC TAPE (From Standards Proposal No. 940 formulated under the cognizance of EIA Subcommittee P-8.6 on Magnetic Tape, Reels and Containers.) 1. SCOPE 1.1 This method measures the susceptibility of magn
7、etic tape to layer-to-layer adhesion between adjacent layers of a tape roll. This Standard was prepared because no other comparable indus- try-accepted document relating specifically to the subject matter contained herein is in ex- istence. 2. SIGNIFICANCE 2.1 Adhesion, or clinging, of one layer of
8、tape to an adjacent layer may prevent the reel of tape from unwinding freely. In severe cases, adhesion may be so great that portions of the magnetic coating are disengaged as the tape is unwound. 3. DEFINITION 3.1 The adhesion between one layer of a magnetic tape and the adjacent contacting layer.
9、4. APPARATUS 4.1 The apparatus shall consist of weights, a section of hollow tube and a conditioning apparatus. 4.2 The weights to be used shall be dependent on base film thickness as well as tape width. 4.2.1 For nominal base film thicknesses of 0.00050” (0.0 127mm) and 0.00075” (0.0 19 1 mm) the w
10、eight shall be 4.4 lbs./inch (78 gm/mm) of tape width. 4.2.2 For nominal base film thicknesses of 0.001” (0.0254mm) and 0.0015” (0.0381mm) the weight shall be 8.8 lbs./inch (1 57 gm/mm) of tape width. 4.3 The tube shall be made of a non-oxidizing metal. It shall be 1/2” (12.7mm) in diameter, 4” (1 0
11、2mm) in length and weigh between 15-30 grams. It shall be capable of being mounted in bearings so that it may be rotated freely around its central axis and be easily removed from the bearings. The conditioning apparatus shall be capable of maintaining an enclosed space under the con- ditions of temp
12、erature and humidity required during conditioning of the specimen. 4.4 O - - - EIA 339 b7 3234600 OOb5903 7 I. 1 RS-339 Page 2 5.1 6.1 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 7.9 5. CONDITIONS Observations shall be made under the following ambient conditions: 70f 5 F. (21 & 3 C) 50 k 5% R. H. 6. TEST SPECIM
13、EN The sample shall consist of a 3 foot or 1 meter length of new, clean tape. 7. PROCEDURE Fasten one end of the tape sample to the hollow tube, coating side down. The method em- ployed to secure the tape is optional, but if an adhesive material is used, its thickness should be minimal. Mount the tu
14、be in the bearings so that the free end of the tape hangs below the tube. Prepare a weight as specified in paragraph 4.2 above. Attach the weight to the free end of the tape sample. Affix a small strip of double coated adhesive tape to the coated surface of the tape sample 1 inch above the weight. N
15、ote: The adhesive tape used should be narrower than the magnetic tape sample to prevent oozing of adhesive onto adjacent layers of the sample. Rotate the tube so that the tape, held in tension by the weight, winds uniformly around the tube. Take care to insure that the roll has no protruding, unsupp
16、orted turns, within which un- duly high radial pressures may develop. The strip of adhesive tape acts to secure the roll and prevent it from unwinding when the weight is removed. Note: It is recommended that clean, lint-free gloves be worn when winding the tape sample to prevent contamination. Remov
17、e the weight. Place the tube and rolled sample in the conditioning apparatus and maintain the sample at, 130 k 5 F. (54 f. 3 C), 85 k 5% R. H. for 16 hours, then, immediately, at 130 f 5 F (54 k 3 C), O-5% R. H. for 4 hours. At the end of the conditioning cycle, remove the tube and rolled sample fro
18、m the conditioning apparatus and allow the sample to equilibrate at least one hour at the conditions of testing. _? EIA 339 67 m 3234600 0065704 9 m - RS-339 Page 3 7.10 To evaluate the sample for layer-to-layer adhesion, carefully open the end of the roll and re- move the double coated tape. 7.10.1
19、 Hold the tube horizontally by its ends so that the end of the tape is free. Observe whether the outer layers of the roll loosen up of their own accord. 7.10.2 If no spontaneous loosening of the outer layers of the roll occurs, slowly rotate the tube in the direction which would unwind the tape. Obs
20、erve whether the tape will unwind unaided. 7.10.3 If the tape does not unwind freely as the tube is rotated, manually unwind 9 inches (23 cm) of the free end of the tape. Mount the tube in the bearing, and position the tube so that the free length of tape hangs vertically below the tangent point on
21、the roll. Observe whether the tape continues to unwind, pulled by the weight of the free length of tape. 7.10.4 If the tape does not continue to unwind, rotate the tube through % revolution in the direction of tape unwind. Observe whether the tape now unwinds unaided. 7.10.5 If none of the above mea
22、sures causes the tape to unwind without aid, grasp the free end of the tape and allow the tube to fall, thereby unwinding the tape. 7.1 1 Examine the unwound tape for evidence of coating delamination. 8. REPORT 8.1 The report should include the following: 8.1.1 Weight used. 8.1.2 The conditions (tem
23、perature and humidity) and duration of sample conditioning. 8.1.3 Observations as to the looseness or adherence of the tape sample. 8.1.4 Description of area of coating delamination, including distance from the attached end of the tape. If adhesion is found only in areas of repeat impressions from the tape end attached to the tube, note this.
