Release Base Paper

Release base paper is the high-density base paper a release liner starts from — supplied uncoated, before silicone coating, to the coating lines that turn it into the substrate of release liners. Glassine release bases, CCK release bases, kraft release bases and other specialty release grades are coated from this kind of stock, so the paper is bought for its density, low air permeability, very smooth surface and strength, not for any release coating of its own.

As a paper supplier and sourcing partner, Bofeng supplies release base paper in rolls, uncoated, in basis weights of 28, 35 and 40 gsm. Tell us the release liner you produce and the coating line you run, and we will match grammage, density and surface to your process.

What is release base paper

Release liners are usually made in two steps: a dense base paper is produced first, and a silicone release coat is applied later. Release base paper is the first of those two layers — the uncoated, high-density, low-air-permeability base that keeps the later silicone coat on the surface, where it cures evenly and releases cleanly. At this stage the paper carries no release coating, so what you are choosing is the base itself: density, barrier to air, an ultra-smooth surface, and strength for high-speed coating, drying and rewinding.

Key material properties

• High density, low air permeability. The dense sheet limits the passage of air and keeps a later silicone layer from soaking into the sheet, so the coating stays where it is needed.
• Very smooth surface. A supercalendered finish gives the even, closed surface that silicone systems need to coat uniformly at high speed.
• Strength for the coating line. Good tensile, tear and burst strength let the base run through coating, drying and rewinding without breaks.
• Stable moisture. Moisture is controlled within a narrow range, so the roll behaves consistently from batch to batch.
• Clean, uniform base. Low impurity and low ash keep the surface free of the spots and roughness that can interrupt an even silicone coat.

Supply forms and options

• Rolls, uncoated, in basis weights of 28, 35 and 40 gsm.
• Custom slit widths; basis weight and surface finished toward the release liner you coat, on request.

Typical end uses

Release base paper is converted on silicone coating lines into the base of release liners. Depending on grade it becomes:

• Glassine release bases
• CCK (clay-coated kraft) release bases
• Kraft release bases
• Other specialty release bases

See also the next-stage pages in this family: Glassine Release Paper · Glassine Silicone Paper · Label Facestock Base Paper.

How to order and choose

Release base paper is specified by basis weight — 28, 35 or 40 gsm — to match the caliper and density the finished release liner needs. Request samples to trial on your own coating line; tell us the release liner you make, the coating you apply and the width you need, and we will recommend a starting grade.

Bofeng New Materials supplies release base paper in rolls to silicone coating lines and release-liner converters worldwide.

Request samples or a quote: jason.zhan@bofmat.com

Related: Release Base Paper · Glassine Release Paper · Glassine Silicone Paper · Label Facestock Base Paper