Improved Sutherland Ink Rub Tester
For Abrasion Resistance Of Printed Materials By Sutherland Rub Tester
Only Tester Used In Establishing ASTM Designation D 5264 Standard Test Method
Sutherland Ink Rub Tester
The tester is a motor driven instrument for moving a weighted test strip over a printed specimen through an arc. The Sutherland Rub Tester has been redesigned to improve its operation. James River's corporate research and development laboratories did extensive testing of the Sutherland Rub Tester. The result of this work is an affordable abrasion testing instrument that retains all the features that made it an industry standard plus improvements that ensure it will remain the industry standard.
The stroke of the tester has been shortened which increases the precision and more closely simulates abrasion damage found in the field. James River research and other published work in the print abrasion testing arena have shown that quick strokes simulate some types of rub damage (most notably shipping damage).
Illustrated is the Sutherland Rub Tester showing two-pound and four-pound weights to which test specimens are attached and the scoring device.
The upper receptacle of the timer is for remote timer control. The lower receptacle is the same voltage as the instrument. 110 volts single phase is standard. 220 volts optional at extra cost.
The Sutherland®2000™motor now has four speeds; the first speed (21 cycles per minute) is half the speed as the older models, which will make the "wet" tests, and tests using under 5 strokes easier to perform. The second speed (42 cycles per minute) are the same as the older models, while the fourth speed (106 cycles per minute) is faster. These new improvements will allow the customer the ability to customize the testing procedure more to their individual product, yet maintaining the ability of duplicating a procedure used by someone with an older model unit. The higher speeds will reduce the long test times needed for certain types of substrates (plastics, UV varnished, printed films, etc.).
The Sutherland®2000™ incorporates a digital counter with a fiber optic sensor to ensure the accuracy of the number of rubs for a given test. Simply enter the number of rubs desired and the instrument will stop automatically at exactly the correct number of strokes.
A single mounting pad for the test strip is now cut to fit the weight. It was found that precision of the test is increased by using a 2 inch (5 cm) by 4 inch (10 cm) pad on the bottom of the weight . Two pound and four pound weights and scoring fixture are included.
A supply of 80 x 80 count bleached muslin cloth (cloth not included) has been found useful in testing wet smear, wet rub, and wet bleed. The Sutherland Rub Tester is designed to evaluate the scuffing or rubbing resistance of the printed or coated surface of paper, paperboard, film, etc. The test results are reproducible.
The following tests may be made with the instrument:
Dry Rub
Wet Rub
Wet Bleed or Transfer
Wet Smear
Functional Rub
Test Specimen
The test requires two pieces of stock, the printed test specimen and a test receptor, which is usually unprinted. Cut a test specimen, approximately six by three inches, representing average ink lay and coverage. When the printed area permits, the six inch direction should be cut across the grain of the sheet, but must not cross pressed or cut scores.
Prepare test strips of unprinted material from the same shipment of stock used in printing the test samples. Cleanly cut 2 x 7 inch strips for the four-pound weight are prepared by placing a strip face down against the end pin of the scoring device and scoring the strip at the white dot positions to facilitate bending the strip to conform to the test block.
To prepare samples for the two-pound weight, 2 x 5-1/4 inch strips are placed face down against the end pin of the scoring device and score at the red dot position to facilitate bending the strip to conform to the test weight.