Abstract
Dynamics and ribbing instability for Newtonian and viscoelastic liquids have been investigated in both rigid and deformable forward roll coating flows. Especially, the role of viscoelasticity of coating liquids and roll deformability or hardness on the coating flow has been scrutinized. Coating thickness at steady uniform states and wavelength and severity at unstable ribbing states have been measured, incorporating thickness measurement device and two-roll coating equipment. Relationship between wavelength and severity in ribbing instability strongly depends on the viscoelasticity as well as other operating conditions such as capillary number, coating gap, and roll deformability. Coating windows demarcating uniform and ribbing instability are considerably reduced by increasing viscoelasticity and decreasing roll deformability. In other words, ribbing is aggravated as the viscoelasticity of coating liquids that can generate the extensional property in film splitting region rises or roll deformability decreases, leading to higher severity and narrower wavelength.
| Original language | English |
|---|---|
| Pages (from-to) | 75-80 |
| Number of pages | 6 |
| Journal | Korea Australia Rheology Journal |
| Volume | 22 |
| Issue number | 1 |
| Publication status | Published - 2010 Aug 19 |
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Keywords
- Coating window
- Forward roll coating
- Ribbing
- Roll deformability
- Severity
- Viscoelasticity
- Wavelength
ASJC Scopus subject areas
- Condensed Matter Physics
- Materials Science(all)
Cite this
Ribbing instability in rigid and deformable forward roll coating flows. / Lee, Je Hoon; Han, Sang Kwon; Lee, Joo Sung; Jung, Hyun Wook; Hyun, Jae Chun.
In: Korea Australia Rheology Journal, Vol. 22, No. 1, 19.08.2010, p. 75-80.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Ribbing instability in rigid and deformable forward roll coating flows
AU - Lee, Je Hoon
AU - Han, Sang Kwon
AU - Lee, Joo Sung
AU - Jung, Hyun Wook
AU - Hyun, Jae Chun
PY - 2010/8/19
Y1 - 2010/8/19
N2 - Dynamics and ribbing instability for Newtonian and viscoelastic liquids have been investigated in both rigid and deformable forward roll coating flows. Especially, the role of viscoelasticity of coating liquids and roll deformability or hardness on the coating flow has been scrutinized. Coating thickness at steady uniform states and wavelength and severity at unstable ribbing states have been measured, incorporating thickness measurement device and two-roll coating equipment. Relationship between wavelength and severity in ribbing instability strongly depends on the viscoelasticity as well as other operating conditions such as capillary number, coating gap, and roll deformability. Coating windows demarcating uniform and ribbing instability are considerably reduced by increasing viscoelasticity and decreasing roll deformability. In other words, ribbing is aggravated as the viscoelasticity of coating liquids that can generate the extensional property in film splitting region rises or roll deformability decreases, leading to higher severity and narrower wavelength.
AB - Dynamics and ribbing instability for Newtonian and viscoelastic liquids have been investigated in both rigid and deformable forward roll coating flows. Especially, the role of viscoelasticity of coating liquids and roll deformability or hardness on the coating flow has been scrutinized. Coating thickness at steady uniform states and wavelength and severity at unstable ribbing states have been measured, incorporating thickness measurement device and two-roll coating equipment. Relationship between wavelength and severity in ribbing instability strongly depends on the viscoelasticity as well as other operating conditions such as capillary number, coating gap, and roll deformability. Coating windows demarcating uniform and ribbing instability are considerably reduced by increasing viscoelasticity and decreasing roll deformability. In other words, ribbing is aggravated as the viscoelasticity of coating liquids that can generate the extensional property in film splitting region rises or roll deformability decreases, leading to higher severity and narrower wavelength.
KW - Coating window
KW - Forward roll coating
KW - Ribbing
KW - Roll deformability
KW - Severity
KW - Viscoelasticity
KW - Wavelength
UR - http://www.scopus.com/inward/record.url?scp=77955567886&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77955567886&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:77955567886
VL - 22
SP - 75
EP - 80
JO - Korea Australia Rheology Journal
JF - Korea Australia Rheology Journal
SN - 1226-119X
IS - 1
ER -