FINAT FTM 9
Loop Tack Testing

---

Pressure-sensitive adhesives (PSAs) are essential in packaging, labeling, and other industrial applications, where their initial tack—the ability to quickly grab a surface—is critical. The FINAT FTM 9 test method provides a reliable and standardized procedure for measuring this property through a loop tack configuration.

Used globally in quality control and R&D, FINAT FTM 9 plays a crucial role in helping manufacturers select the most effective adhesive materials, particularly for high-speed automatic labeling lines. In this article, we will delve into the loop tack test method, its importance, procedures, equipment requirements, and how Cell Instruments’ LTT-01 Тестер петельних закріплювачів ensures compliance with the standard.

---

What Is FINAT FTM 9?

FINAT FTM 9 is a standardized test method published by FINAT (the European association for the self-adhesive label industry) for determining the петельна прихватка of pressure-sensitive materials. Tack, distinct from adhesion or cohesion, refers to the adhesive’s ability to form an immediate bond with a substrate under brief contact and minimal pressure.

This method offers a practical way to compare the “grab” strength of different label or tape materials, a property that is especially relevant in fast-paced application environments such as labeling machinery.

---

Why Is Loop Tack Testing Important?

У "The петельна прихватка value directly correlates with application performance, especially in systems where the adhesive must bond instantly with minimal dwell time. A high loop tack value indicates better immediate adhesion, critical in:

• Labeling machines where materials must bond instantly
• Medical tape applications
• Consumer packaging requiring instant closure
• Temporary bonding needs

Accurate measurement of loop tack helps manufacturers control quality, fine-tune formulations, and meet customer performance expectations.

---

Loop Tack Test Method Overview

У "The loop tack test method, as defined in FINAT FTM 9, involves bringing a looped strip of pressure-sensitive material into contact with a standard substrate (typically float glass), then separating it at a fixed speed to measure the peak force of detachment.

Test Equipment

• A tensile tester or universal testing machine with a vertical jaw separation speed of 300 mm/min, reversible direction, and force measurement up to 20 Newton with ±2% accuracy.
• A glass plate measuring 25 mm × 30 mm (± tolerances), attached to a peg for mounting.

---

Sample Preparation and Conditioning

• Strips should be 25 mm wide and 175 mm long, cleanly cut.
• Backing material is removed just before testing.
• Strips are looped with adhesive side out and clamped into the tester’s upper jaw.
• Test conditions are set at 23°C ± 2°C and 50% RH ± 5% with a minimum 4-hour conditioning period for both test specimens and substrate.

---

Test Procedure

1. Loop the adhesive strip and insert it into the upper grip.
2. Clamp the cleaned glass plate into the lower grip.
3. Bring the adhesive loop into contact with the substrate at 300 mm/min.
4. Immediately reverse direction to separate the loop at the same speed.
5. Record the peak force (excluding initial noise spikes).
6. Repeat with five samples and report the average value in Newtons.

Notations:

• If tearing occurs before adhesive release → mark with PT (paper tear).
• If adhesive transfers to the plate → mark with AT (adhesive transfer), noting approximate percentage.

---

Factors Influencing Test Accuracy

Several variables can affect loop tack results:

• Substrate cleanliness – Use non-residual solvents like MEK, acetone, or n-heptane. Repeat cleaning three times and let plates condition for 4 hours before use.
• Sample rigidity – Affects loop shape and contact area.
• Environmental conditions – Must be strictly controlled as tack is sensitive to humidity and temperature.

---

Why Choose Cell Instruments’ LTT-01 for Loop Tack Testing

У "The LTT-01 Тестер петлевої затяжки from Cell Instruments is designed specifically to meet FINAT FTM 9 requirements with:

• Precision mechanics ensuring consistent 300 mm/min contact/separation.
• Touchscreen control and programmable test sequences for repeatability.
• Data output in Newtons, including automatic averaging of multiple runs.
• Compliance with global standards for tack testing.

For manufacturers and labs aiming to ensure consistent product quality or meet regulatory and customer-specific adhesive performance benchmarks, LTT-01 offers the ideal balance of accuracy, usability, and reliability.

---

Conclusion

У "The FINAT FTM 9 loop tack test method is a critical tool for evaluating the initial tack of pressure-sensitive adhesives. By adopting this standardized approach and using reliable instruments like the LTT-01 Тестер петлевої затяжки from Cell Instruments, manufacturers can ensure high-performance bonding in labeling, packaging, and medical applications.

Understanding loop tack values is not just about numbers—it’s about optimizing performance, reducing failure rates, and improving end-user satisfaction.