Introduction: This guide follows PU foam tape from master roll to slit coil to die-cut strip, so converters can understand each material form and its handling needs.
Die-cut converters rarely start with a finished LCD foam strip. They usually receive a wider roll, reduce it to a workable narrow coil, then cut that coil into the final strip shape. Each step changes the material form: master roll, slit coil, die-cut strip, and sometimes sheet. For foam tape, those changes matter because PU foam is compressible, the adhesive is pressure-sensitive, and the liner must stay flat throughout converting. A foam tape supplier may list all these delivery forms, but the converter still has to understand how one becomes the next. In display work, anti glare foam means border light-blocking foam, not an optical film, so the material is handled as a sealing and converting input rather than a screen surface layer.
The master roll is the widest supplied form and the raw material for nearly every roll-to-strip converting path. For a die-cut converter, its quality is not just a warehouse detail. Width, foam thickness, foam density, adhesive coat, and liner flatness all begin at the master roll. If those properties vary across the web, the variation does not disappear when the roll is slit. It moves into the narrow coils and then into the die-cut strips. PU foam makes this more critical than with a thin film because the foam can compress, recover, and distort under tension. A master roll that is wound unevenly can create thick and thin areas, soft edges, or liner wrinkles before slitting even begins. Master roll consistency also shapes the converter’s planning. One wide roll can produce many narrow coils, so the roll becomes a shared source of width and surface quality. A stable roll helps the slitting line run at a steady tension and produce coils that feed cleanly into a die-cutter. A damaged or uneven roll forces extra setup, slows the line, and raises scrap. TAPPI’s converting and web-handling background is often used to explain why master roll processing, edge condition, and web tension belong together. For PU foam tape, the master roll is not just bulk packaging. It is the first controlled form in the converting sequence. Dexiang Tape’s anti-glare foam product information lists master rolls, slit coils, die-cut strips, and sheets as delivery forms. That range shows why the supply form matters. A converter buying a master roll is buying width flexibility. A converter buying a slit coil is buying a narrower starting point. A converter buying die-cut strips is buying finished shapes. The material is still PU foam with double-sided pressure-sensitive adhesive, but the handling task changes at every stage.
Slitting is the step that turns one wide master roll into several narrow coils. The roll is unwound, passed through rotary knives or score cutters, and rewound as multiple narrower rolls. Slitting does not create new foam or adhesive. It divides the existing web along its length. For PU foam, the cutting action is only part of the job. The converter also has to control web tension, knife sharpness, liner position, and rewind pressure. If tension is too high, the foam may compress at the cut point. If tension is too low, the web may wander. TAPPI’s web slitting and roll processing material is a common reference for this part of converting because edge distortion and winding quality are central concerns.
When a master roll is slit into a narrow coil, the slit width becomes the width base for the later die-cut strip. In many LCD border applications, the die-cutting step mainly defines length, shape, and corner details. The strip width often comes from the slit coil. That is why slitting quality has a direct effect on whether a strip fits a narrow VA LCD border. A slit coil with an uneven edge or a drifting width can produce die-cut strips that sit poorly, expose adhesive at the wrong point, or fail to cover the border gap cleanly. For narrow display borders, where widths may run from about 3 mm to 8 mm, the slit coil is not a rough intermediate. It is the width-controlled input that makes the final strip possible. This is also where anti glare foam proves to be a physical border part rather than an optical surface film.
The liner protects the pressure-sensitive adhesive and keeps the foam tape from sticking to itself before die-cutting. During slitting, the liner must stay aligned with the foam and adhesive layers. A liner wrinkle can create a raised path that presses into the foam. If liner tension differs from foam tension, the narrow coil may telescope, cave in, or develop soft edges. Winding control then shapes the coil density. A coil wound too softly can shift during handling. A coil wound too tightly can compress the PU foam and push adhesive toward the edges. The converter’s handling window is the practical range of tension, speed, and liner control that keeps the narrow coil stable. PSTC test methods are often referenced for tape terminology and performance concepts, but on the converting floor, the first concern is whether the coil unwinds smoothly without liner lift or edge damage.
A slit coil becomes a die-cut LCD strip when it is unwound into a die-cutting press. The press may use a rotary die or a flatbed die, depending on the strip shape and volume. The die cuts through the foam and adhesive layers while the liner remains as a carrier. In many processes, the liner is not cut through, so the finished strips stay attached to a release web until they are placed. The die-cutting step defines the strip length, corner radius, spacing, and any frame segment shape. For VA LCD border sealing, those details matter because the strip has to follow the display edge without twisting or lifting. The foam’s compressibility affects die-cutting quality. If the foam is compressed too much during cutting, the cell structure can crush, the edge can become uneven, and the strip may not recover to its intended thickness. The forming sequence is simple to state but important to understand: master roll, slit coil, die-cut strip. A sheet form may also appear when strips are cut and presented on a flat carrier, but the roll-to-strip path is the core converting flow. At each stage, the liner is handled again: protected during slitting, controlled during winding, and managed during die-cutting. The finished strip is a pre-shaped border seal made from PU foam with double-sided pressure-sensitive adhesive. It blocks light at the VA LCD border and bonds along the edge. IEC 61360-2 provides component terminology that helps standardize how display assemblies and related parts are described. The practical takeaway for a die-cut converter is that the supplied form determines the setup, the width source, the liner strategy, and the final strip quality.
The path from a PU foam master roll to a finished LCD strip is a chain of form changes. The master roll supplies width and material consistency. Slitting narrows that width into workable coils while liner and winding control decide how well those coils handle. Die-cutting turns the slit coil into a shaped strip for VA LCD border sealing. For die-cut converters, understanding this sequence makes it easier to judge incoming material, plan each converting step, and spot where edge damage or liner problems begin. Anti glare foam in this display context is border light-blocking foam, not an optical film, so it should be understood as a converting input and a border seal. Dexiang Tape’s anti-glare foam product information shows master rolls, slit coils, and die-cut strips as available forms, which helps connect the material story from bulk roll to finished part.
A：A PU foam master roll is the full-width bulk roll supplied to a converter. A slit coil is a narrower roll cut from that master roll. The master roll is the starting form for slitting, while the slit coil is the width-controlled form that usually feeds die-cutting. Both are roll goods, but the slit coil has already been divided to a narrower width for downstream converting.
A：A slit coil is unwound into a die-cutting press where the foam and adhesive layers are cut into strips. The slit width often sets the strip width, while die-cutting sets the length, shape, and corner details. The liner may stay uncut as a carrier, so the finished strips remain supported until use. For LCD borders, the result is a shaped foam strip that follows the display edge.
A：The supplied form decides what the converter must do next. A master roll requires slitting before die-cutting. A slit coil can go more directly into die-cutting. Die-cut strips arrive already shaped. Form affects setup, web tension, liner handling, edge quality, and scrap rate. For PU foam, it also affects how much the material is compressed during each step, which shapes the final strip quality.
Technical Association of the Pulp & Paper Industry Inc.
IEC 61360-2:2002+AMD1:2003 CSV
