A liquid crystal display is prepared by laminating a polarizing plate on at least one side (usually on each side) of a liquid crystal cell having liquid crystal sealed in between a pair of substrates. As the polarizing plate, it is common to employ one prepared by having a polyvinyl alcohol type film dyed with iodine or a dichromatic dye, stretching it for orientation in a predetermined direction to form a polarizing film, and laminating, on each side of the polarizing film, a triacetyl cellulose film having no optical isomerism and being excellent in transparency, as a protecting film. In the process for assembling a liquid crystal display or in the distribution process of a polarizing plate, a surface protection film is stuck on the surface of the polarizing plate opposite to the adhesive layer of the polarizing plate, to prevent damages or soiling. As the surface protection film, it is common to employ one having an adhesive coated on one side of e.g. a polyester film or a polypropylene film. The surface protection film is peeled off, when the liquid crystal display is to be used, or when the liquid crystal display is to be tested for evaluation of e.g. the display ability, the color, the contrast, etc.
Surface protection films having antistatic treatment applied, are reported in JP-A-2000-026817, JP-A-2000-085068, JP-A-05-331431 and JP-A-09-207259.
In JP-2001-096698, a surface protection film having an antifouling layer provided, is reported. Further, surface protection films having the antifouling properties of their surfaces improved, are reported in JP-A-6-256756 and JP-B-6-29332.
The degree of fineness of liquid crystal display has increased, and fine letters can now been displayed. Along with such progress, the density of the TFT drive elements has increased, and the wiring has become thin. It has not been a serious problem that the static electricity generated when the surface protection film is peeled from a liquid crystal display, induces a trouble of attracting dusts. However, as the degree of fineness of liquid crystal display increases, the liquid crystal display tends to receive a direct hazard by static electricity. There has been a problem such that due to static electricity, abnormal display is induced, or malfunction or an electrostatic discharge damage of the TFT drive elements, tends to be led.
Problems relating to the surface protection film are not limited to static electricity.
In a quality test of a polarizing plate, marking is made by an ink to the surface protection film bonded to the polarizing plate. The surface protection film is required to have a nature such that marking can easily be imparted by an ink and it can not easily be removed even by wiping. This is contradictory to such a requirement that the surface protection film should scarcely be soiled. The surface protection film is required to satisfy the opposing or contradictory characteristics, such as the stain proofing property and the ink fixing property at the same time.
The liquid crystal display surface having anti-glare treatment applied, is surface-roughened. When a surface protection film is stuck thereto, the film and the display surface will not adhere intimately, whereby there may sometimes be a problem that fine air bubbles interposed therebetween present a haze or turbidity. With a TFT type liquid crystal display, areas of individual display elements are very small. Accordingly, even fine air bubbles adversely affect the evaluation of visibility. And, it is necessary to carry out an inspection by peeling the surface protection film.