Patent TW-201702320-A (TW)
Title: High quality and high precision screen printing ink composition having durability and flexibility, printed matter screen-printed using the same, and production method of the printed matter which is able to make the ink composition for screen printing for the printed matter with a slumping width of 10 <mu>m or less on the edge of contour portion in any part of the printed image
Inventor: OGATA TOMOMI
IPC: C09D1/10
Filed: 2016-03-03
Abstract: PROBLEM TO BE SOLVED: Recently, in the screen printing of electrical/electronic parts on a substrate of thermoplastic resin, the demand towards developing diversification of designs in printed matter and high precision of the printed image in the pattern-decorative screen printing, and towards simple and low-cost production of the printed matter with coexistence of wide-area solid pattern and fine pattern has been increased. Also, in the solid pattern, by means of enhancing sharpness of the image edge portion in combination with a better leveling property, the quality and higher precision in identifiability of the printed image in the coexisted fine and solid patterns is required to be even higher. Furthermore, the flexibility in three-dimensional formation is also required for the aforementioned high-quality, high-precision printed matter. SOLUTON: A screen printing ink composition for a substrate of thermoplastic resin, which is able to make the ink composition for screen printing the printed matter with a slumping width of 10 [mu]m or less on the edge of contour portion in any part of the printed image after the printing in terms of the image design dimension of the aforementioned printed matter having the coexisted solid and fine image patterns when the printed matter is made by screen printing on the substrate of thermoplastic resin using a screen printing plate with 360 meshes made of a high-strength, deformation-free stainless steel screen net with a radius of 25 [mu]m; characterized in that the measured value of the flowing radius of the aforementioned ink composition 1 minute after the beginning of measurement is 13.0~24.0 mm, according to JIS K5701-1: 2000 for the measurement of flowability using the parallel plate viscometer (diffusion meter) under 25 DEG C. If the measurement value of flowing radius measured (1 minute after the beginning of measurement) by the flowability measurement method using the aforementioned parallel plate viscometer is defined as [F60] and the measurement value of flowing radius 45 seconds after the beginning is defined as [F45], [F60]- [F45] <=1.0 mm. The viscosity measured by the BH-type rotary viscometer under 25 DEG C is 5~180 Pas. The rheology (TI value) is 2.0~8.0. This invention contains thermoplastic polymer containing a solvent having a boiling point of 170 DEG C for 70 mass% of the entire solvent, with the weight average molecular weight being above 4000 for 10 mass% more of the total amount of aforementioned ink composition, and Tg being 20~95 DEG C, and a printed matter with the extension rate of 250% or more in its printed image coating film can be made when the vacuum molding or compression molding processing is carried out.