Abstract
In recent years, polymer components with surface microstructures have been in rising demand for applications such as lab-on-a-chip and optical components. Injection molding has proven to be a feasible and efficient way to manufacture such components. In injection molding, the mold surface topography is transcribed onto the plastic part through complex mechanisms. This replication, however, is not perfect, and the replication quality depends on the plastic material properties, the topography itself, and the process conditions. This paper describes and discusses an investigation of injection molding of surface microstructures. The fundamental problem of surface microstructure replication has been studied. The research is based on specific microstructures as found in lab-on-a-chip products and on rough surfaces generated from EDM (electro discharge machining) mold cavities. Emphasis is put on the ability to replicate surface microstructures under normal injection-molding conditions, i.e., with commodity materials within typical process windows. It was found that within typical process windows the replication quality depends significantly on several process parameters, and especially the mold temperature. For the specific microstructures, evidence suggests that step-height replication quality depends linearly on structure width in a certain range.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Michaeli W, Spennemann A (2000) Mikrostrukturierte Funktionsoberflächen spritzgießen. Kunststoffe 90(9):52–57
Wimberger-Friedl R (2001) Injection moulding of deep sub-micron gratings. Materialen 1:21–24
Mönkkönen K, Hietala J, Pääkkönen P, Pääkkönen EJ, Kaikuranta T, Pakkanen TT, Jääskeläinen T (2002) Replication of sub-micron features using amorphous thermoplastics. Polym Eng Sci 42(7):1600–1608
Yoshii M, Kuramoto H, Ochiai Y (1998) Experimental study of the transcription of minute width grooves by injection moulding (II). Polym Eng Sci 38(9):1587–1589
Bushko WC, Dris I, Avagliano A (2001) Effects of material and processing parameters on the degree of groove replication in DVD disks, Antec Technical Papers, Paper no. 0153
Christensen TR (2002) Sprøjtestøbning af miniature- og mikrokomponenter (in Danish), ATV-SEMAPP seminar 18.09.2002
Despa MS, Kelly KW, Collier JR (1998) Injection moulding using high aspect ratio microstructures mould inserts produced by LIGA technique. Proc SPIE, 3512:286–293
Yu L, Koh CG, Lee LJ, Koelling KW, Madou MJ (2002) Experimental investigation and numerical simulation of injection moulding with micro-features. Polym Eng Sci 42(5):871–888
Theilade UA, Hansen HN, Kjær EM (2003) Injection moulding of microstructures. Proceedings of the 1st CIRP Seminar on Micro and Nano Technology. Micro Engineering., Department of Manufacturing Engineering and Management, Technical University of Denmark, pp 61–64
Lonardo PM, Lucca DA, De Chiffre L (2002) Emerging trends in surface metrology. Ann CIRP 51(2):701–723
De Chiffre L, Lonardo P, Trumpold H, Lucca DA, Goch G, Brown CA, Raja J, Hansen HN (2000) Quantitative characterisation of surface texture. Ann CIRP 49(2):635–652
Jansen KMB, Van Dijk DJ, Husselman MH (1998) Effects of processing conditions on shrinkage in injection molding. Polym Eng Sci 38(5):838–846
Jansen KMB, Pantani R, Titomanlio G (1998) As-molded shrinkage measurements on polystyrene injection molded products. Polym Eng Sci 38(2):254–264
Ni S (2000) Preventing sink marks of injection molded parts using CAE analysis. Antec Technical Papers
Moldflow MPI 4.1 electronic documentation (2003) Moldflow Corporation
Skands U, Wahlberg P, Palfelt B,. Borregaard L, Alexandersen NB, Johansen T, Rønning A, Russ JC (1998) Surface analysis of injection molded TV components. Int J Mach Tools Manuf 38:477–484
Schauf D (1998) Reproducing textures from the cavity surface to the surface of the thermoplastic. Bayer, Plastics Business Group, Application Technology Information, ATI 584e
Malloy RA (1994) Plastic part design for injection molding. SPE, Hanser Publishers, Munich
Stout KJ, Blunt L (2000) Three-dimensional surface topography, 2nd edn. Penton Press, London
De Chiffre L, Kunzmann H, Peggs GN, Lucca DA (2003) Surfaces in precision engineering, microengineering and nanotechnology. Ann CIRP 52(2):561–577
Thomas TR (1999) Rough surfaces, 2nd edn. Imperial College Press, London
Jarnov C, Staun J (2003) Validation study of mouldflow plastics inside (in Danish). Internal report, Department of Manufacturing Engineering and Management, Technical University of Denmark
Bariani P et al (2003) Comparative investigation of optical techniques for topography measurement of rough plastic surfaces. Int Topical Conf on Precision Eng, Micro Tech, Measurement Techn and Equipment, euspen, May 19–20, 2003, in Aachen, Germany, pp 455–458
UBM Microfocus measurement system, manuals. UBM Messtechnik GmbH, Ettlingen
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Theilade, U.A., Hansen, H.N. Surface microstructure replication in injection molding. Int J Adv Manuf Technol 33, 157–166 (2007). https://doi.org/10.1007/s00170-006-0732-y
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00170-006-0732-y