Cailong

Use the published Polyester Twist Film PET-NJ specification to set the first trial gauge and treatment. The wider functional BOPET film range helps the converter check adjacent PET options, and the Cailong product portfolio locates other Cailong materials. The tamarind candy and wrapper establish the final result.

A closed twist is a process result

Individually wrapped tamarind candy places unusual stress on a twist package. The product may be sticky, irregular in shape or dusted with sugar. If film stiffness, cut length and twist settings are poorly matched, the ends can spring open, the film can tear at the twist neck or the wrapper can feed inconsistently. A material trial should therefore reproduce the actual candy surface, room conditions and wrapping speed.

What the PET-NJ specification establishes

Cailong's Polyester Twist Film PET-NJ product page lists candy and biscuit wrapping and identifies rigidity, twist forming and twist retention as core characteristics. It provides a thickness range of 19–25 μm and a typical light-transmission value of 88% under GB/T 2410. The page also distinguishes corona and non-corona wetting-tension values. These figures help define the sample, but they do not replace print, cutting and wrapping tests on the buyer's line.

Do not treat thickness as the only control

A thicker film may feel stiffer, yet twist performance also depends on orientation, slit quality, storage, printed ink coverage and the geometry of the candy. Ask the converter to keep roll width, cut length, print build and machine settings traceable. Check whether defects occur at startup, after the roll warms on the machine, or only at the highest speed. That pattern can separate a film-handling problem from a twist-setting or product-surface problem.

Compare against the current wrapper fairly

Run PET-NJ and the approved control with the same candy lot. Record missed feeds, web breaks, loose twists, neck tears, product exposure and packs per minute. After wrapping, inspect twist recovery immediately and again after transport simulation and storage at the target market conditions. If graphics are printed, confirm ink adhesion on the intended treated side and verify that the finished wrapper still gives the required product visibility.

Prepare a useful twist-wrap sample request

Send the candy dimensions, surface condition, current film and gauge, roll width, cut length, printing process, wrapper model, operating speed and the defect photos. Include the number of twists per end and the time at which relaxation appears. Cailong can then match the request to the PET-NJ thickness and treatment information already published, while the manufacturer and converter retain responsibility for the finished-pack approval.