Pressure Sensitive Seals Cap Liners, 56 mm

Sealing inserts for jars, pressure-sensitive, 56 mm

Pressure-sensitive sealing inserts close a jar without heat and without any equipment. Simply place them inside the lid and they adhere to the neck when the lid is tightened. The result is a sealed jar whose contents neither leak nor dry out, and the customer can immediately see that no one has opened the product before them. The inserts are designed for cosmetics and are suitable for jars containing creams, butters, balms, scrubs, or loose preparations.

How a sealing insert works

The insert is a white polyethylene disc with an adhesive layer on one side. It is placed inside the lid with the adhesive side facing the jar neck. When the lid is screwed on, the tightening pressure presses the insert against the rim of the neck and the adhesive layer bonds. On first opening, the insert remains stuck to the neck and the customer peels it off by hand.

What the insert provides

• Seal – the insert closes the jar neck and reduces leakage during transport or if the packaging is tipped over.
• Content protection – the sealed neck slows drying of creams and butters and limits air and contaminant access to the product before first use.
• Visible first opening – an intact insert shows that the packaging is originally sealed. A peeled insert cannot be re-applied.
• Simple processing – sealing can be done by the producer without additional machinery, which is practical for small batches and home production.

Sealing procedure

The jar neck should be clean and dry before sealing. Residues of cream, oil, or dust on the rim of the neck reduce adhesion and the insert may not seal properly at that spot. The insert is placed in the lid with the adhesive side facing outward, the lid is screwed on and tightened firmly. With the first batch, we recommend opening the jar after sealing to check that the insert adheres around the entire circumference of the neck.

What is good to know

The insert is intended for single use. Its purpose is to seal the packaging from filling until first opening; it does not replace the lid seal during everyday opening. After peeling, the jar is closed only with the lid.

The insert diameter must correspond to the inner diameter of the lid, not the jar volume. Jars and lids with the same neck size can be found in the Handymade range. For your own combination, we recommend verifying that the insert lies flat inside the lid and seals properly when tightened.

Difference from an induction insert

An induction insert is heat-welded to the neck using an induction device and creates a firm bond suitable even for liquid contents. A pressure-sensitive insert adheres only by the pressure of the lid and requires no equipment, but the bond is mechanically weaker. For small batches and thicker contents, the pressure-sensitive insert is more practical; for liquid contents and higher sealing requirements, the induction insert is more suitable.

Frequently asked questions