Analysis of chemical properties of polarizers

  The optical functions of the polarizer include: the three primary functional objectives of polarizing, transmittance and color. Others include UV protection and transmissivity, total reflectance and diffuse reflectance of the semi-transmissive polarizer. . In the usual use of LCD products, the higher the target of the required polarization and transmittance functions, the better. The higher the degree of polarization and transmittance, the higher the apparent power of the LCD display device and the lower the relative energy consumption. However, for polarizer products that are routinely iodine-stained, the degree of polarization and transmittance are opposite. The higher the degree of polarization, the lower the transmittance, and the color is bound, so usually the ordinary type Polarizers have a polarization between 90% and 99% and a transmittance between 41% and 44%. Guangdong Fudi Rihe Polarized Light Equipment Co., Ltd. produces "Fudi" brand polarizer. The general-purpose PLN product has a polarization degree of 97% or more and a transmittance of 43%, while the medium-durability and high-comparison PMN products have a polarization degree of 99.9%. Above, the transmittance is 42% or more. The color target is mainly to satisfy everyone's visual habits. The color error of the polarizer products is small to ensure the commonality of the appearance color of the LCD end products. This is mainly due to the chromaticity coordinate parameters L, a, b of the polarizer product and They are manipulated by the size of the public service, and the smaller the size of the public service, the better.

The bonding characteristics of the polarizer The skill objective mainly refers to the characteristics of the polarizer pressure sensitive adhesive, which usually includes: peeling force between the pressure sensitive adhesive and the glass substrate, peeling force between the pressure sensitive adhesive and the peeling film, and polarizer protection The peeling force between the film and the polarizer and the bonding durability of the pressure sensitive adhesive. The peeling force between the pressure sensitive adhesive and the glass substrate is also called the adhesive strength of the adhesive, which is the most important adhesive property target of the LCD polarizer. This skill target is usually measured by the Japan Electromechanical Industry Association specification EIAJ-ED-2521A specification, and is indicated in g/25mm. Generally, the peeling force of the LCD polarizing pressure sensitive adhesive on the glass substrate is more than 500g/25mm. In practice, the upper limit is usually below 1000g/25mm. There are practical cases in which, when the peeling force of the adhesive on the glass substrate is below 500 g/25 mm, the appearance of the active peeling and warpage of the polarizer after the glass panel is bonded to the outside is caused.

The durability skills of polarizers include four objectives of high temperature resistance, heat and humidity resistance, low temperature resistance and thermal shock resistance. The most important thing is the unevenness of the target of resistance to heat and humidity. High temperature resistance refers to the temperature resistant working condition of the polarizer at a stable baking temperature. Currently, it is generally classified into a general type according to the skill level of the polarizer: the working temperature is 70 ° C × 500 HR; the medium durable type: the working temperature is 80 ° C × 500HR; high durability type: the working temperature is three levels of 90 ° C × 500H. The heat and humidity resistance target refers to the heat and humidity resistance function of the polarizer under constant temperature and humidity conditions. It is also usually divided into three skill levels, which are general type: wet heat working condition is 40 ° C × 90% RH × 500 HR; medium durable type : Damp heat working conditions are 60 ° C × 90% RH × 500 HR; high durability type: damp heat working conditions: 70 ° C × 95% RH × 500 HR or more. Because the fundamental data of the polarizing film, the PVA film and the iodine and iodide are very simple hydrolysis materials, together with the pressure sensitive adhesive used in the polarizer, it is also easily deteriorated under high temperature and high humidity conditions, and thus, the durability of the polarizer. The most important of the sexual skill goals is the target of high temperature and humidity resistance. If the target of high temperature and heat and humidity is passed, other durability targets are usually not questioned.

The appearance of the polarizer The functional skill target is mainly the appearance flatness of the polarizer product and the number of appearance defects. These skill objectives mainly affect the utilization of the polarizer product in the patch. These skill targets usually have a common skill rule in the polarizer occupation, usually 15 points below each polarizer (500×1000mm) and no more than 150μm. Because the end appearance of polarized film products is viewed by manual visual inspection, in the mass production process of polarizer products, there will be a certain discrete dispersion of the appearance of the under-printed products. For each of the polarizing film production companies, the selection is inevitable. The difference between the internal control specification and the delivery specification to ensure delivery quality specifications. But probably note that because 150μm is already close to the minimum limit of human eye discrimination, especially in the industrial mass production process, the viewer will have visual fatigue in the long-term work, so the 150μm under-point viewing specification is more reasonable. Letter.