Tape roll

Vinyl backed packaging tapes are quite popular in Europe. The vinyl backing is commonly manufactured using a calendering process. Printability and smooth unwind of the tape rolls are amongst the desirable features of these tapes. 

Release coatings are important components of pressure sensitive adhesive (PSA) products such as tapes and labels [1]. Release materials are coated onto the backside of PSA tape backings (often called low adhesion backsizes or LABs in this form) to provide the desired tape roll unwind force. They are also coated onto various substrates to form release liners for PSA products such as labels and transfer tapes. Typically the thickness of the release coating is less than 1 p,m, and often times less than 0.1 jLm. Release coatings can be thought of as the PSA delivery system, providing a controlled unwind or release force and protecting the adhesive from contamination and unintentional contact until it is applied. 

In the laboratory, aerosol samples were individually cut from the filter-tape roll and extracted on a 47-mm filter holder (Millipore) with 200 mL of distilled deionized water maintained at 50-60 °C. The leachates were analyzed for sodium content by flame atomic absorption with a Perkin-Elmer Model 373 spectrophotometer. The soluble sodium was assumed to be derived only from sea salt. Estimates of total sea salt in each sample were obtained by multiplying the sodium value by 3.25, which is the salinity-to-sodium ratio in bulk seawater (12). The sodium content of the 5-cm diameter, glass-fiber filter blanks averaged 18 /xg 12% (20 samples). Based on an average sample volume of 27 m, the background salt level produced by the sodium blank in each filter would be equivalent to 2.2 /xg/m. ... 

The case is made from a 10" length of the 3" gummed tape rolled arotmd another length of dowel. This is best done by first rolling up the entire length, keeping the ends even, then unrolling all hut... 

Laser cutting allows for almost free design of the microfluidic channels in the tape gasket. Figure 5 shows laser-cut double-sided adhesive tapes with microfluidic channels. The tape adhesive is still protected by its liners. The tape cutting can also be depth sensitive, i.e., kiss-cuts down to the carrier liner can be done if the tape roll is used in further automated roll-to-chip or manual tape-to-chip bonding processes. 

For high efficiency, coating usually is performed over a width of more than a meter. The tape rolls are obtained by cutting the web into strips with a width of a few millimeters up to several centimeters. Four methods are applied (Fig. 18). 

Shear cutting (Fig. 18 A) is effected between a rotating knife and a roller edge and results in tapes with smoothly cut edges. This method has the highest precision, but the width of the tape rolls cannot readily be changed. It is used for most rigid-film tapes and double-sided tapes. 

In log cutting (Fig. 18 C) the coated web is wound into rolls or logs in full width and in the desired length of the tape rolls. Subsequently, these logs are sliced by a rotating knife, which is moved transversally between slices to match the width of the tape rolls. As the transverse location can be adjusted deliberately by a computer, this process allows the complete customization of the width of the tape rolls. 

Sealing Tapes.The 100% solids, preformed tape sealants, because of their form and ease of handling, provide economies in installation often unattainable with other sealants. Tape rolls are available in a variety of widths and thickness and many times contain an embedded string or cured rubber core to prevent stretching or drawdown in use. All tapes have some degree of pressure sensitivity and are sufficiently soft to allow for ease of compression during installation. 

Foil duct tapes, used in North America for heating, ventilation and air conditioning systems, are constructed of 50 pm aluminum foil coated with 50-100 pm of an acrylic dispersion PSA to provide high adhesion and functionality at extreme use temperatures. Once coated, the adhesive is covered with a release liner to prevent adhesion to the top side of the foil and subsequent blocking of the tape roll. Some foil tapes use strands of fiber reinforcement laminated between foil and kraft paper layers to improve tensile strength [24]. 

In order to understand and avoid lot-to-lot variations within the tape rolls, the ASTM standard advises that a peel test be performed on a tape lot at the start of the testing. This peel test is performed by adhering the tape to a smooth and hard surface such as a glass surface. Next, the peel force is measured using an Instron by pulling the tape from the flat surface at either 90° or an 180° angle. 

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