Information on the most widely used ASTM standards within the materials testing industry
Model: UT2047; ASTM D3121, JIS Z0237
Initial Adhesion Tester also known as a Primary Adhesive Tester, Rolling ball initial tack tester, initial tack tester, tackiness tester, is a specialized device used to check the initial sticking performance of products like pressure-sensitive tapes, medical plasters, and adhesive labels. The device works on the inclined plane ball method principle, testing adhesion through the instant contact pressure between a steel ball and the sample surface.
It follows standards ASTM D3121, GB/T 4852, JIS Z0237 for adhesion testing. The instrument mainly consists of an inclined plate, a ball dropper, a stand, and standard steel balls, with adjustable angles from 0° to 60° and a test width of 80mm. During testing, the sample is placed on the adjustable platform, and steel balls ranging from 1/32 inch to 1 inch in diameter are released. The result is based on the median size of the largest adhered ball. The device features a three-station design, meeting the testing needs of pharmaceutical companies, quality inspection centers, and other areas for products with different tackiness.
General introduction
Initial Tack Tester (Rolling Ball Primary Adhesion Tester) | Multi-Station PSA Tack Measurement Instrument | UnitedTest
UnitedTest is a professional manufacturer of adhesive performance testing instruments. Our inclined plane rolling ball initial adhesion tester — also widely named primary adhesive tester, initial tack tester or tackiness tester — delivers standardized instant tack testing for all pressure-sensitive adhesive materials, fully complying with global mainstream industrial standards.
What Is an Initial Tack Tester & Core Test Principle
This specialized lab testing device quantifies the instant initial sticking performance of PSA products, including pressure-sensitive adhesive tapes, medical adhesive plasters, self-adhesive labels, protective films and sticker substrates. It operates on the classic inclined plane rolling ball method: calibrated steel balls roll down an adjustable inclined track and generate instant contact pressure against the adhesive sample surface to measure raw tackiness without sustained loading.
Global Standard Compliance
Our rolling ball tack tester is engineered to meet three authoritative testing specifications for adhesive tack evaluation:
ASTM D3121 Standard Test Method for Tack of Pressure-Sensitive Adhesives by Rolling Ball
GB/T 4852 Chinese national standard for initial tack test via inclined ball method
JIS Z0237 Japanese industrial standard for pressure-sensitive tape tack measurement
Three-Station Design & Industrial Application
Our machine adopts a practical three-station simultaneous testing design, allowing operators to test three different adhesive samples in one single cycle and boost lab inspection efficiency. It serves rigorous quality control, raw material screening and product R&D demands across pharmaceutical medical factories, official quality inspection centers, label packaging manufacturers, electronics component labs and daily chemical adhesive production facilities for materials with varying low, medium and high tack levels.
Key Features
Using Method A inclined plane ball rolling test and Method B inclined trough ball rolling test:
Method A: Tests the initial tack of the sample by the adhesive tape’s stickiness to a steel ball when brief contact occurs under slight pressure between the steel ball and the adhesive side of the tape. A steel ball is rolled over the adhesive side of the tape placed on a tilted plate, and the initial tack is evaluated based on the largest ball size the tape can hold over a specified length of the adhesive surface.
Method B: A steel ball of a specified size is rolled down an inclined trough, and the distance it rolls on a horizontal board with the adhesive side of the tape is measured to evaluate its initial tack.

1. Overall high-quality aluminum profile design, beautiful and durable;
2. Innovative precision control angle adjustment device, angle adjustment is more convenient, accuracy is better;
3. Fine steel ball position control knob, convenient steel ball before and after the left and right position adjustment;
4. Steel ball is made of GCr15 bearing steel, steel ball shape tolerance and surface roughness accuracy level exceeds GB/T308 specified level 40 or more.
ASTM D3121 Standard Test Method for Tack of Pressure-Sensitive Adhesives by Rolling Ball
JIS Z 0237 Testing methods of pressure-sensitive adhesive tapes and sheets
GB/T 4852 Test method for tack of pressure sensitive adhesive tapes by rolling ball
AS 2313.1.3 Methods of test for single sided and double sided pressure-sensitive adhesive tape - Adhesion - Rolling ball tack
PN-EN 1721 Paste for paper and board, packaging and disposable hygienic products -- Measurement of adhesive tack -- Measurement of tack by rolling ball method
EN 1721 Adhesives for paper and board, packaging and disposable sanitary products - Tack measurement for pressure sensitive adhesives - Determination of rolling ball tack
1. Use a spirit level to fix the rolling ball device horizontally on the tester, and set the inclined surface to the standard angle of 30°. If needed, you can also set it to 20° or 40°.
2. Use positioning adhesive tape or pull-off tape (about 500 g) at the lower end of the test piece to fix it in the specified position with the adhesive side facing up. Attach the assist rolling section to the designated position on the test piece's adhesive surface using polyvinyl film, making sure that no air bubbles or wrinkles form and no excessive pressure is applied. When fixing the test piece, make sure it doesn’t warp or bulge. If bulging occurs at the edges, use additional adhesive tape to fix that part to the inclined surface.
3. To keep the length of the assist rolling section constant at 100 mm, adjust the ball center to the starting position according to the size of the ball.
4. Take the ball stored in anti-rust solution with tweezers, clean the test ball, and after washing, place it at the starting position to roll it down the assist rolling section.
5. Cleaning the test ball: Clean the surface of the test ball with a degreased cloth soaked in solvent. After the surface dries, wipe again with a new clean cloth soaked in solvent. Repeat this process at least three times until it looks visually clean.
Note:
1) Use cloths, non-woven fabrics, or similar materials that do not shed short fibers and contain no substances soluble in the solvent.
2) Use solvent-grade or residue-free industrial-grade solvents like naphthenic hydrocarbons, mineral spirits, alcohol, isopropanol, toluene, etc.
6. Pre-select the largest steel ball: Adjust the starting position, use different sizes of balls, and repeat the cleaning and rolling process. Choose the largest ball that stops within the measuring section (remains stationary for more than 5 seconds). Take the largest ball found on the same test piece and the two balls with adjacent sizes, and test each once on the same sample to confirm the largest ball size. Before selecting the largest ball, you can roll several times on the same test piece, but these cannot be counted as official test data.
7. Official testing: Take three test samples and use the largest steel ball for one rolling test on each. If a sample cannot hold this steel ball, use one size smaller for testing. If it still cannot hold, repeat steps 6–7.
8. Test results: The test result is expressed as the median ball size (number) from the rolling tests of the three samples in the official test.
Adhesives: Including various adhesives, e.g. pressure-sensitive tapes, medical patches, adhesive labels and protection films.
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UnitedTest initial tack tester, inclined rolling ball primary adhesion tester, ASTM D3121 tackiness measurement instrument, three-station PSA tape initial adhesion test machine, 0–60° adjustable inclined plane ball tack tester, 1/32" to 1" steel ball initial stickiness test, 80mm width medical plaster label tack inspection bench, ASTM D3121 GB/T 4852 JIS Z0237 compliant rolling ball tack equipment, multi-station instant tack tester for pharmaceutical QC labs
The complete tester assembly consists of an adjustable inclined plate, precision steel ball dropper, stable support stand, and a full set of standard stainless steel test balls. Key configurable parameters:
Adjustable inclined test angle range: 0° to 60° for flexible test condition setup
Standard test sample width: 80 mm to fit most industrial adhesive strip specimens
Full steel ball kit: sizes ranging from 1/32 inch up to 1 inch in diameter
During standard testing procedures, adhesive samples are fixed flat onto the adjustable inclined platform; graded steel balls are released to roll across the tacky surface. The final initial tack result is judged by the median diameter of the largest steel ball fully retained by the adhesive surface.
Main Technical Specification
| Angle range | 0 ~ 60° |
| Panel Width | 120mm |
| Testable Area Width | 80mm |
| Standard Steel Ball | 1/32 inch ~ 1 inch (29 pcs) |
| Number of Stations | 6 |
| Weight | Frame: 6Kg |
| Dimension | 320*140*180mm (LWH) |
| Main accessories | Frame, standard steel ball |
Standard
ASTM D3121 – Standard Test Method for Tack of Pressure-Sensitive Adhesives by Rolling Ball
ASTM D3121 defines methods of comparative initial tack (instant stickiness) of pressure-sensitive adhesives (PSAs) via a rolling steel ball approach
ISO 29863 Self adhesive tapes – Measurement of static shear adhesion
ISO 29863 evaluating the load-bearing performance of pressure-sensitive adhesive (PSA) tapes, developed jointly with the International Association for the Self Adhesive Tape Industry (AFERA) and the Pressure Sensitive Tape Council (PSTC).
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