Guillotining
Polystar synthetic papers can be guillotined without difficulty to the same tolerances as paper. It is recommended to keep blades sharp and use light-clamping pressures due to compressibility of the material.
Die Cutting
Cutting dies with flame-hardened steel cutting edges up to 55 on the Rockwell "C" scale is recommended (rather than the standard 45- 48 used with paper). Use of base steel rule material supplied by material suppliers such as: Bohler (#75) and Sandvik (#XD-700) is best. The standard 60 degree included angle can be used when die cutting thin gauge film materials; 52 degree angle for gauges from 0.20mm (8 mil) to 0.35mm (14 mil); long center bevel or 42 degree bevel is suggested for thicknesses over 0.35mm (14 mil).
Perforating
Polystar synthetic papers has an excellent perforation results range from 13 TPI to 70 TPI (ties per inch). It is recommended that cuts extend to the edge of the material to initiate tear.
Drilling, Punching & Cornering
Polystar synthetic papers can be drilled, punched and cornered. It is suggested to keep cutting tools sharp to prevent initial tear strength reduction. During drilling and cornering, it is recommended that a short dwell time be used in order to eliminate heat generation, which may cause fusion of the edge of the sheets. It is also advised to keep drills bits sharp and do not exceed one-inch stack height when drilling.
Folding
Polystar synthetic papers can be folded like paper of equivalent bulk on normal sheet folding machines. For bookmaking, signatures of up to sixteen pages can be formed. Trials are recommended if more pages are required.
Stitching
Polystar synthetic papers may be saddle stitched with wire or sewn on signature with sewing machines.
Scoring
Polystar synthetic papers performs well in most bindery operations. When applying unconventional scoring, it is recommended to perform scoring in the cross machine direction as opposed to the machine direction. This will show Polystar synthetic papers’ excellent endurance as High Impact Polystyrene (HIPS) without tearing due to the pressure during scoring process.
Binding
Polystar synthetic papers can be used for case making through the use of plasticized animal glues or flexible synthetic emulsions. It is suggested to apply special care where water is present.
Polystar synthetic papers can be used as end papers, or alternatively, end-sheet papers may be bonded to the sheet covered cases.
Polystar synthetic papers can be used for perfect binding using suitable hot melt adhesive. The surface area for bonding may be increased by cutting a number of slots into the spine of the book. It may also be used for drawn-on covers.
Polystar synthetic papers is suitable for ring binding as long as the precautions given for drilling and punching are observed.
Bonding
Polystar synthetic papers may be bonded to itself and to other substrates using various adhesives (synthetic, solvent or hot melt).
Heat-Sealing
Polystar synthetic papers is heat-sealable to itself. The heat-seal strength can reach 1563 grams at 150°C. Depending upon which grade is used, different heat-sealing processes can be applied.
Coatings and Varnishes
The following conditions and recommendations are a reference for the initial set up.
Utilize inks consisting of 100% solids that contain less than 3% mineral oil, and can be dried by oxidation. Wax-free inks are indicated for use, when images are to be over coated or imprinted. Use high color strength fresh inks. Compatibility testing under end use conditions should be done on printed Polystar synthetic papers sample using the proposed coatings and adhesives.
It is suggested to carry out testing prior to converting processes. For sample request, specification of Polystar synthetic paper, or finishing processes, please Contact Us to obtain more information.