Show simple item record

dc.contributor.authorBenkreira, Hadj
dc.contributor.authorShibata, Yusuke
dc.contributor.authorIto, K.
dc.date.accessioned2017-03-10T12:17:00Z
dc.date.available2017-03-10T12:17:00Z
dc.date.issued2017
dc.identifier.citationBenkreira H, Shibata Y and Ito K (2017) Reverse roll coating with a deformable roll operating at negative gaps. Chemical Engineering Science. 165: 204-215.en_US
dc.identifier.urihttp://hdl.handle.net/10454/11580
dc.descriptionYesen_US
dc.description.abstractReverse roll coating is probably the most widely used coating operation, yet its full potential has not been exploited as it is shown in this paper which considers operation with a negative gap. We demonstrate through a wide range of experimental data that such operation can yield very thin and stable films with no ribbing or cascade instabilities when low viscosity fluids are used. Typically, stable film thickness less than 5μm can be obtained at speeds up to 150 m/min when a rubber roller is used at -100 μm gap with fluids of viscosity in the range 10-200 mPa.s. These film thicknesses can be made to decrease further down to 1 or 2 microns with a judicious choice of speed ratios (applicator to metering roller) and rubber hardness. Such new findings make this simple coating method an attractive roll to roll technique for application in the newer coating technologies, such as in the production of solar cells and plastic electronics. The data obtained in this study have been underpinned by a model based on the classical lubrication theory, well developed for such flow situations. Essentially it is shown that the film thickness non dimensionalised with respect to the set negative gap is controlled through a single parameter, the elasticity number Ne which combines all the operating parameters. Of course, this flow problem has complexities, particularly at high speed ratios and at zero gap so the data obtained here can serve as a basis for more comprehensive modelling of this classical fluid mechanic problem.en_US
dc.description.sponsorshipFilms R&D Centre of Toyobo Co. Ltd., Otsu, Japan and the Thin Films Research Group of the University of Bradford, UK.en_US
dc.language.isoenen_US
dc.relation.isreferencedbyhttp://dx.doi.org/10.1016/j.ces.2017.02.034en_US
dc.rights© 2017 Elsevier. Reproduced in accordance with the publisher's self-archiving policy. This manuscript version is made available under the CC-BY-NC-ND 4.0 license (http://creativecommons.org/licenses/by-nc-nd/4.0/)en_US
dc.subjectReverse roll coating; Deformable; Degative gap; Thin films; Cascade; Ribbingen_US
dc.titleReverse roll coating with a deformable roll operating at negative gapsen_US
dc.status.refereedYesen_US
dc.date.Accepted2017-02-16
dc.date.application2017-03-06
dc.typeArticleen_US
dc.type.versionAccepted Manuscripten_US
refterms.dateFOA2018-03-07T00:00:00Z


Item file(s)

Thumbnail
Name:
benkreira_et_al_2017.pdf
Size:
1.241Mb
Format:
PDF
Description:
Keep suppressed - has older cover ...
Thumbnail
Name:
benkreira_et_al_2017.pdf
Size:
1.259Mb
Format:
PDF

This item appears in the following Collection(s)

Show simple item record