Curable organopolysiloxane release agent composition for thermal paper, thermal paper, and thermal recording label sheet

Abstract

[Problem] To provide a curable organopolysiloxane release agent composition for thermal paper that does not tend to gel at room temperature, has excellent handling and workability, and is capable of curing without curing failure in a short time at low temperature to form a release layer having good peeling force and high adhesiveness when applied to a thermal coloring layer, and a thermal paper and the like using the same. [Solution] A curable organopolysiloxane release agent composition for thermal paper containing (A) one or more types of organopolysiloxane having a C4-12 alkenyl group in which the vinyl (CH2=CH-) moiety content in the alkenyl group is 0.5-3.0 mass%, (B) an organohydrogenpolysiloxane having two or more silicon-bonded hydrogen atoms (Si-H) in the molecule, (C) a hydrosilylation reaction catalyst, and (D) a hydrosilylation reaction inhibitor, the amount of silicon-bonded hydrogen atoms in component (B) being in a range of 1.0-4.0 mol per mol of carbon-carbon double bonds in component (A); and the use thereof.

Description

technical field [0001] The present invention relates to a curable organopolysiloxane release agent composition for thermal paper, a thermal paper using the same, a thermal recording label sheet, and a method for producing the same. The oxane release agent composition is not easy to gel at room temperature, has excellent handling workability, and can be cured without causing poor curing at a low temperature and in a short time when it is applied to a heat-sensitive color-developing layer, thereby forming a good Excellent peeling force and high adhesion peeling layer. Background technique [0002] Thermal paper is used in various applications such as train tickets, bill paper, thermal FAX paper, electricity and gas meter reading paper, and labels for displaying prices in convenience stores and supermarkets. Such thermal paper is usually stored in a roll form, and the entire surface or a part of the thermosensitive color-developing layer formed on the substrate is printed by a...

AI Technical Summary

Problems solved by technology

[0003] However, when conventional hydrosilylation-reactive silicone-based release agents are used for the top coat / release layer of thermal paper, there are the following problems: Due to the high-temperature heating above 100°C that is indispensable for the usual hydrosilylation reaction, the thermosensitive color-developing layer reacts and the entire thermal paper develops or changes color, or the printing of the thermal head becomes inconspicuous

However, in general, it is not economical to increase the amount of hydrosilation reaction catalysts using precious metals such as platinum, and thermal paper designed and produced as consumables has its own limit to the amount that can be used in industrial production.

In addition, if the addition amount of the hydrosilylation reaction catalyst in the silicone-based release agent composition increases, there is a problem that the expected service life (pot life) is significantly reduced when the coating bath is adjusted at room temperature, Gelling occurs in a short time, resulting in a decrease in handling workability

When it is necessary to extend the pot life of ordinary silicone-based release agents, there are solutions to increase or optimize the hydrosilylation reaction inhibitor in the composition, but as mentioned above, it cannot be used for thermal paper Very high heating temperature, and it is not preferable to increase the cycle time, so it is difficult to design a silicone-based release agent suitable for thermal paper by adjusting the type or amount of hydrosilylation inhibitor

[0005] In addition, there is a problem that the heat-sensitive color-developing layer contains a large amount of nitrogen / sulfur-containing compounds as a color-developing agent, but they cause hydrosilylation for the use of precious metals such as platinum Catalyst poisoning of the reaction catalyst, even if simply increasing the amount of the hydrosilylation reaction catalyst, it is easy to cause a decrease in the adhesion of the peeling layer due to poor curing

Therefore, if the type of the heat-sensitive color-developing layer or the content of the color-developing agent are changed, there are cases where the silicone-based release agent cannot be used industrially unless the curing conditions or the amount of the catalyst are optimized. the inconvenience of

[0006] As mentioned above, the thermal paper has multiple characteristics. When trying to apply the conventional hydrosilylation-reactive silicone-based release agent, it is often easy to solve each other. It becomes a problem of contradictory results and becomes a factor that hinders the industrial popularization of silicone-based release agents in thermal paper applications

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