Cap Liner Types and Functions
Polyethylene Foam Liners
An ideal general-purpose liner material, the compressible PE foam creates a stable seal.
- Good resistance to acids, alkalis, solvents, alcohols, oils, household cosmetics, and aqueous products.
- Fair to poor resistance to hydrocarbon solvents
A pressure sensitive foam liner with one adhesive side that sticks to the container with the pressure used to secure the closure onto the container. When the closure is removed, the pressure sensitive liner remains on the top of the container.
- Require no machinery for application
- Provides an added layer of protection while storing
Once the liner has been removed, it cannot be reapplied to the container.
Creates an airtight seal to help prevent leakage
- Must be applied using an induction sealing machine
Poly Vinyl Liners
A pulp / poly liner consists of a poly-vinyl film adhered to a white pulp paper backing.
- Chemical resistance to mild acids, alkalis, solvents, alcohols, oils and aqueous products
- Not recommended for active hydrocarbons or bleaches
- Stress crack resistant
- Superior torque retention
- Excellent sealing characteristics
Teflon® PTFE Liners
A variety of liners may have Teflon® facing, such as silicone or PE foam. A Teflon® -faced liner will maintain the base liner's sealing properties while adding superior chemical resistance.
- Withstands volatile solvents, sensitive compounds and corrosive chemicals that would degrade other liner materials.
- Good barrier properties
- Good resistance to hydro carbonates, oils, ketones and alcohols
- Not recommended for acids or alkalis.
- Tamper evidence
- Hermetic seal
- Must be used with containers that can withstand high heat.