Liquid crystal sealant composition

Abstract

The invention provides a liquid crystal sealant composition, which is an ultraviolet / thermal dual curable resin composition for sealing liquid crystal by a one drop fill (ODF) process, and comprises the following components in parts by weight: 40-80 parts of acrylic acid modified hyperbranched organosilicon epoxy resin, 2-15 parts of grafted hyperbranched epoxy resin coupling agent, 0.5-8 parts of photoinitiator, 5-25 parts of latent epoxy resin curing agent, and 5-40 parts of filler. The inventive composition has good coating operability and high bonding strength, solves the problem of contamination to liquid crystal existing in the conventional sealing material, and increases the bonding strength between a substrate and cured liquid crystal sealant, thus a liquid crystal display panel with high display performance and excellent quality can be manufactured, and the production efficiency is greatly improved.

Description

Technical field [0001] The present invention relates to the technical field of liquid crystal display panel packaging, in particular, to a liquid crystal sealing compound composition. Background technique [0002] In recent years, with the advancement of broadband and the development of small electronic devices such as digital cameras and mobile phones, the demand for liquid crystal display panels as flat panel display devices has rapidly expanded in terms of thinness, light weight, and low power consumption. [0003] The LCD panel is mainly manufactured by the liquid crystal injection method. There are two methods for the liquid crystal display packaging process. One is the vacuum suction method, that is, screen printing is used on an IT0 quartz glass plate with etched TFT transistors and printed alignment film. Make a rectangular pattern with a liquid crystal suction port, and then pre-baked at 60-100 ℃, dry the solvent in the sealant, and then drop a spacer into it, press and al...

AI Technical Summary

Problems solved by technology

This production method has the following defects: dislocation due to hot pressing and uneven gap, damage to the adhesive strength of the sealant and the substrate; foam formed by thermal expansion of the remaining solvent causes uneven gap and displacement of the sealant; curing sealant requires It takes a long time; the pre-baking process is very complicated; because the volatilization of the solvent makes the available time of the sealant very short, it takes a long time to inject the liquid crystal, etc.

[0006] In recent years, due to the implementation of energy saving and consumption reduction, the industry tends to low-voltage liquid crystal display devices (low-voltage liquid crystals). Low-voltage liquid crystals are very easy to absorb impurities. Over time, it is easy to form high dielectric Electrical anisotropy, which is easy to cause orientation disorder and reduce voltage retention rate, that is: due to the absorption of uncured photoinitiator and thermal curing agent, ionized compound, silane coupling agent, etc., it will cause liquid crystal orientation disorder and voltage over time Lower retention rate etc.

[0007] For this reason, people have been studying countermeasures, such as reducing the amount of initiator used in the system or using a polymer initiator to reduce the extraction of the liquid crystal to the initiator, but these behaviors not only cannot fully inhibit the liquid crystal from eluting the initiator, It also leads to insufficient curing of the reaction system or reduces the reactivity of the initiator, resulting in higher curing conditions, which will have a negative impact on liquid crystals

[0008] In addition, as for ionic impurities, it has been reported that the sealing agent, end-capping material and raw materials thereof are washed with water or organic solvents, and then dried under negative pressure to remove ionic impurities, but the operations required for this method are very complicated, and this method will also Causes some problems: If the sealant and its raw materials are not dried enough, there will be residual solvents, or during the drying process, negative pressure will cause the sealant to cure, etc.

Although the two-component composition can be cured at room temperature, the cured resin (main reagent) and curing agent should be stored separately, and the respective components should be taken out and mixed when used, so storage and handling are complicated. In addition, because the storage period is limited, Therefore, the individual components cannot be pre-mixed, and frequent mixing is required, resulting in inefficiency. On the contrary, one-component compositions, in some cases, react during storage, so storage stability needs to be improved. Therefore, when using epoxy resin as In the case of curing resins, a one-component cured resin composition using dicyandiamide as a curing agent is well known, but the resin composition requires a curing problem not lower than 160 ° C, which will not meet the requirements in recent years. The requirement of fast curing at low temperature, for this reason, some people propose to use amine and epoxy resin adduct as curing agent, and some people propose to use imidazole encapsulated by polymethyl methacrylate as curing agent, using isocyanate as amine Methods of inertizing the surface of curing agent powder, however, these methods are very complicated, and there is also a problem of eluting a large amount of unreacted amine into unreacted liquid crystals

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