Effects of processing conditions on cavity pressure during injection-compression molding

A new technique was proposed and experimentally verified for the cavity pressure acquisition in the injection-compression molding (ICM). The surface strain of the fixed mold half and the cavity pressure were monitored simultaneously during ICM. In the compression stage, a directly proportional relationship between the cavity pressure and mold surface strain was found and determined via the regression analysis. By taking the advantage of this relationship, the cavity pressure profile with high accuracy was indirectly obtained from the nondestructive measurement of the mold surface strain. Moreover, the mold surface strain profile could indicate the part weight or thickness and the critical time when the part surface lost contact with the cavity surface in a large area. The monitoring of the mold surface strain could serve as an interesting alternative to the direct monitoring of the cavity pressure with respect to process and part quality control for ICM.

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A Design Methodology to Replicate the Sub-Micron Land-Groove Structure in DVD-RAM Substrates by Injection-Compression Molding

10.1115/imece2000-1915 ◽

2000 ◽

Author(s):

Kibyung Seong ◽

Su-dong Moon ◽

Hyun Kim ◽

Shinill Kang ◽

Jun-Seok Lee ◽

...

Keyword(s):

Design Methodology ◽

Mold Temperature ◽

Compression Molding ◽

Processing Conditions ◽

Efficient Design ◽

Compression Pressure ◽

Molding Process ◽

Geometrical Properties ◽

Groove Structure ◽

Injection Compression Molding

Abstract Recently, the sub-micron structured substrates of 0.74 μm track pitch and 800 Å groove depth are required for DVD-RAM, and the track pitch is expected to be narrower as the storage density for optical disk is getting higher. For the accurate replication of the land-groove structure in the stamper to the plastic substrates, it is important to control the injection-compression molding process such that the integrity of the replication for the land-groove structure is maximized. However, the determination of the processing conditions has been relied on experience or trial-and-error. In the present study, polycarbonate substrates were fabricated by injection compression molding and the land-groove structure regarded as one of the most important geometrical properties for DVD-RAM substrates was measured. The effects of the mold temperature and the compression pressure on the integrity of the replication were examined experimentally. An efficient design methodology using the response surface method (RSM) and the central composite design (CCD) technique was developed to obtain the optimum processing conditions which maximize the integrity of the replication with a limited number of experiments. The model used in this study was verified using the analysis-of-variance (ANOVA), and it was found to be adequate within the confidence limit.

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Study on Optical Properties of Microstructure of Lightguiding Plate for Micro Injection Molding and Micro Injection-Compression Molding

Materials Science Forum ◽

10.4028/www.scientific.net/msf.505-507.229 ◽

2006 ◽

Vol 505-507 ◽

pp. 229-234 ◽

Cited By ~ 5

Author(s):

Yung Kang Shen ◽

H.J. Chang ◽

C.T. Lin

Keyword(s):

Optical Properties ◽

Injection Molding ◽

Digital Camera ◽

Mold Temperature ◽

Compression Molding ◽

Micro Injection Molding ◽

Melt Temperature ◽

Packing Pressure ◽

Injection Compression Molding ◽

Better Than

The purpose of this paper presents the optical properties of microstructure of lightguiding plate for micro injection molding (MIM) and micro injection-compression molding (MICM). The lightguiding plate is applied on LCD of two inch of digital camera. Its radius of microstructure is from 100μm to 300μm by linearity expansion. The material of lightguiding plate uses the PMMA plastic. This paper uses the luminance distribution to make a comparison between MIM and MICM for the optical properties of lightguiding plate. The important parameters of process for optical properties are the mold temperature, melt temperature and packing pressure in micro injection molding. The important parameters of process for optical properties are the compression distance, mold temperature and compression speed in micro injection-compression molding. The process of micro injection-compression molding is better than micro injection molding for optical properties.

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A Theoretical Analysis on Resin Injection/Compression Molding

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.334-335.209 ◽

2007 ◽

Vol 334-335 ◽

pp. 209-212 ◽

Cited By ~ 1

Author(s):

Akbar Shojaei ◽

A. Spah

Keyword(s):

Analytical Solutions ◽

Mold Filling ◽

Compression Molding ◽

Fiber Content ◽

Flow Front ◽

Transfer Molding ◽

Unidirectional Flow ◽

Resin Injection ◽

Filling Time ◽

Injection Compression Molding

In the present investigation, mold filling process of resin injection/compression molding (RI/CM) is compared with resin transfer molding (RTM) for simple mold geometry. To do this, analytical solutions are obtained for RI/CM in unidirectional flow. Based on the analytical solutions, flow front progression and pressure distribution are compared with RTM at different fiber content. The results indicate that the RI/CM reduces the mold filling time significantly, particularly for composite parts with higher fiber content.

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