Microstructure-Forming Mechanism of Optical Sheet Based on Polymer State Transition in Injection-Rolling Process

Abstract

Polymeric optical sheets are significant components in large-scale display devices and are difficult to fabricate due to small size and high accuracy of large-area microstructures. As a newly developed molding technique, injection-rolling is capable of continuously and efficiently achieving large-area microstructures on the polymer surface with short time and high replication. However, the microstructure-forming mechanism during the injection-rolling process has not been fully understood. In this paper, a three-dimensional steady-state heat-flow coupling simulation model of the injection-rolling zone was established to obtain the distributions of the polymer state transition interfaces. According to the state transition interfaces, the entire microstructure-forming process was numerically simulated by dividing into filling and embossing stages to systematically analyze the effects of the polymer state transition interface on filling rate. After this, the relationship between process parameters such as injection temperature, rolling speed, and roll temperature and polymer state transition interface was investigated to develop a position prediction model of the state transition interface. In addition, the optical sheet injection-rolling experiments were also carried out to reveal that the filling rate of the microstructures on the optical sheet can be affected by varying the positions of the state transition interfaces. Therefore, the microstructure-forming mechanism could be revealed as theoretical guidance for the subsequent injection-rolling production with high quality and high efficiency.

Improving the Melt Flow Length of Acrylonitrile Butadiene Styrene in Thin-Wall Injection Molding by External Induction Heating with the Assistance of a Rotation Device

“…Most applications of thin-wall and microinjection molding are in the micro-optics and microfluidic devices market. The development of micro-optical parts of various shapes, such as optical gratings, optical switches, and waveguides [ 1 , 2 , 3 , 4 ], as well as a variety of molded microfluidic devices, including pumps, capillary analysis systems, and lab-on-a-chip applications [ 5 , 6 ], is ongoing.…”

A Study on the Dynamic Forming Mechanism Development of the Negative Poisson’s Ratio Elastomer Molds—Plate to Plate (P2P) Forming Process

“…Moreover, the micro/nano-structural substrates of different sizes and shapes [ 7 , 8 ] prepared by different processing methods (top-down, bottom-up) have high SERS enhancement factors and can be used for medical detection. At present, microstructural components, such as micro-nano gratings [ 9 , 10 , 11 , 12 , 13 , 14 ], polarizers, and lenses, can be completed by technologies such as nano-imprint, exposure, and development [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 ]. However, there is a problem of material selection if etching is used for microstructure fabrication.…”