To realize low void content molded parts, we propose structural resin transfer molding (SRTM) with the compression process. Resin was injected with a gap height between the upper and lower halves of matched metal dies. Mold filling was performed tly a squeezing motion of the upper mold die. The usefulness of the compression process was examined by comparison to a conventional SRTM method. Void disnibution and bending properties in both processes were compared. The SRTM method with compression was better at driving out voids. The effects of the gap height between the upper and the lower halves of the molds and of the gap closure rate during mold closing after injection on the void distribution were examined. The gap height did not affect the void distribution. When the gap closure rate was high, the voids were expelled towards the end of cavity, whereas voids remained on the top surface of the molded parts using a small gap closure rate. The difference in void behavior due to the gap closure rate was determined by a balance of the permeability between the flow and the transverse directions. Effect of Compression Process on VoidBehavior in SRTM l-iiGG4 Fg. 10. Effect of the gap clmure rate on the void behavior when the molded parts were fabricated by changing a stopping position (HI) of the upper half of mild during the mold closing after injection at AH = 12 nun Rg. 1 1 . Comparison of the void behavior between V = 5 and 100 mm/min when the upper mold moved downwardfrom the position ofHl = 1 2 m m t o H 1 = 5 1 m Fg. 12. Analysis model POLYMER

Polymer antireflection structures were fabricated by injection molding using anodic porous alumina or a Ni replica as a mold. An ordered array of tapered pillars or holes was successfully formed on the surface of polycarbonate plates. The obtained polymer antireflection structures exhibit a lower reflectance than a smooth polycarbonate surface.

Three types of glass/nylon 6 intermediate material forms‐film stacking, uncommingled yarn, and commingled yarm‐were selected study the correlations between the impregnating property and mechanical properties. The size of the glass fiber block to be filled with matrix and the porosity in glass fiber bundles by spearing out the fiber bundle was different in these materials. Unidirectional glass fiber reinforced thermoplastic composites were fabricated by compression molding. The being test was performed by using the three‐point loading system, and the fracture behavior and the degree of impregnation were observed to examine the influence of processing conditions on the bending properties, relative to the form of the intermediate material. Bending strength increased, in accordance with the impregnating property, least in the film stacking form, second most in uncommingled yarn, and most in commingled yarn. The impregnating property was affected by the size of fiber blocks and the porosity in fiber bundles, because bending strength was improved by spreading out the fiber bundles. Commingled yarn is an excellent intermediate materials, which has both the fineness of matrix/fiber mixing and large porosity in fiber bundles.

Adhesion between glass/ epoxy composite substrate and copper foil was evaluated by 90 ± peeling test. Effect of fracture behavior and the peel strength on copper foil style was experimentally investigated using copper foils with various surface roughness. As mechanical anchoring effect increases with increased surface roughness, the surface roughness increased the surface roughness of copper foil strongly affected the peeling strength and local load variation during the test. The fracture behavior was characterized by secondary electron image and re ective electron image techniques of scanning electron microscopy (SEM). All of the specimens were found to fracture at the anchor points formed in the resin layer on the surface of the substrate. The experimental results were correlated to a formulation based on the theory of beams on elastic foundation, which is presented for predicting the adhesive strength in the adherend-adhesive system. In order to apply this formulation to a no adhesive system, such as FR-4/ copper foil, an analytical model was proposed. In this model, a mixture phase of the copper with the surface resin in the substrate was regarded as the adhesive. The calculated results were in relatively good agreement with the experimental results. It was con rmed that the analysis model and evaluation method is useful to predict the peel strength due to the mechanical anchoring effect.

Unidirectional composites were fabricated from twistedspun yam commingled of carbon fiber and Nylon 6 fiber by compression molding. Longitudinal bending strengthwas saturated with a rather lower pressure and shorter period of compression. A clear fiber bundles-boundaries pattern is observed. Two steps of impregnation is also presumed.