In the past, the sealing tape used for seaming was made of cellophane, kraft paper, polypropylene film or the like. The pressure sensitive adhesive is applied to one or both sides of the substrate, which has the disadvantage that the edges of the tape are easily torn. In order to avoid this disadvantage, a substrate of a high-strength polyester film has been used. However, the cost of the polyester film substrate is high and it is difficult to apply it widely.

    Recently, the weather strip used as a corrugated cardboard box is mainly made of paper, cloth, polypropylene, and polyvinyl chloride film. Apply hot melt adhesive to one or both sides. The strength of the paper substrate is not high, and the transparent tape material of the paper substrate reinforced with different plastic film or textile is not easy to be broken by hand, and it is inconvenient to use. The transparent tape material of polypropylene and poly-stretched vinyl film substrate has high temperature brittleness. Polyethylene and polyvinyl chloride materials have a high stiffness, a large tensile modulus and an elongation of 5%. Adhesive tapes made of such materials are used as seals for frozen food containers at lower temperatures. In the uneven surface of the passenger's surface, the tape peels off due to tensile stress.

    An adhesive tape that is easy to break by hand is produced, although the tensile strength of the scotch tape material is still high. This scotch tape material is inexpensive and easy to promote. The production process is simple and the cold resistance is very good. The substrate of the tape is made of high-density polyethylene (density greater than 0.94% g/cm3), and the ratio of draw ratio in the transverse direction to the longitudinal direction is 6:1. The polyethylene substrate is coated with a pressure-sensitive adhesive (single-coated On the other hand, the scotch tape material is coated with another layer of pressure sensitive adhesive. A layer of paper can be sandwiched between the high density polyethylene film and the pressure sensitive adhesive.

    Regardless of the form of adhesive tape, it is important that the density of the high-density polyethylene of the scotch tape material should be greater than 0.94% g/cm 3 and that the transverse to longitudinal stretch ratio should be more than 6 times, preferably 10 More than double. The reason why the transparent tape material requires the density of the high-density polyethylene to be not less than 0.94% g/cm 3 is to ensure the substrate has a high transverse strength at a low temperature.