Abstract

A mixture of nematic liquid crystals (NLCs) with a small amount of a polypropyleneimine-based liquid crystalline dendrimer (D-6PC5 and D-6PPCN) exhibited spontaneous homeotropic alignment between the native glass substrates. This dendrimer-induced homeotropic alignment required two conditions; 1) the dendrimer completely dissolves in the NLC, and 2) a substrate surface is hydrophilic with the surface free energy above approximately 65 mN·m−1. The interdigitated-electrode cells without any surface treatment of the substrates were fabricated by filling with the LC dendrimer (D-6PC5)/nematic LC mixtures. They exhibited an electro-optical behavior when applying AC, vertical-alignment drive occurred in the cells. Based on these results, we speculated that the dendrimer adsorbs on the substrate surface and acts as a vertical alignment layer.

© 2014 Optical Society of America

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    [CrossRef]
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    [CrossRef]
  3. M. G. Samant, J. Stöhr, H. R. Brown, T. P. Russell, J. M. Sands, and S. K. Kumar, “NEXAFS Studies on the surface orientation of buffed polyimides,” Macromolecules29, 8334–8342 (1996).
    [CrossRef]
  4. K. Shirota, M. Yaginuma, T. Sakai, K. Ishikawa, H. Takezoe, and A. Fukuda, “Surface orientation of cyanobiphenyl liquid crystal monolayer and pretilt angle under various rubbing strengths,” Jpn. J. Appl. Phys35, 2275–2279 (1996).
    [CrossRef]
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    [CrossRef]
  6. J. C. Jung, K. H. Lee, B. S. Sohn, S. W. Lee, and M. Ree, “Novel polypyromellitimides and their liquid crystal aligning properties,” Macromol. Symp.164, 227–238 (2001).
    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  24. T. Koda, T. Mitsuyoshi, A. Kanazawa, A. Nishioka, K. Miyata, G. Murasawa, S. Ikeda, T. Miura, and Y. Kimura, “Effect of charge transfer complex on electrical properties of 4-cyano-4′-pentylbiphenyl,” Jpn. J. Appl. Phys.48121404 (2009).
    [CrossRef]
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    [CrossRef] [PubMed]

2013

O. Haba, D. Hiratsuka, T. Shiraiwa, T. Koda, K. Yonetake, Y. Momoi, and K. Furuta, “Synthesis and characterization of polypropyleneimine dendrimers having peripheral mesogenic groups: homeotropic orientation and mesogen Structure,” Mol. Cryst. Liq. Cryst.574, 84–95 (2013).
[CrossRef]

2012

Y. Momoi, M. Kwak, D. Choi, Y. Choi, K. Jeong, T. Koda, O. Haba, and K. Yonetake, “Polyimide-free LCD by dissolving dendrimers,” J. Soc. Inf. Display.20, 486–492 (2012).
[CrossRef]

2010

Y. -Q. Fang, J. Wang, Q. Zhang, Y. Zeng, and Y. -H. Wang, “Synthesis of soluble polyimides for vertical alignment of liquid crystal via one-step method,” Eur. Polym. J.46, 1163–1167 (2010).
[CrossRef]

W. -Y. Teng, S. -C. Jeng, J. -M. Ding, C. -W. Kuo, and W. -K. Chin, “Flexible homeotropic liquid crystal displays using low-glass-transition-temperature poly(ethylene terephthalate) substrates,” Jpn. J. Appl. Phys.49,010205 (2010).
[CrossRef]

2009

T. Koda, T. Mitsuyoshi, A. Kanazawa, A. Nishioka, K. Miyata, G. Murasawa, S. Ikeda, T. Miura, and Y. Kimura, “Effect of charge transfer complex on electrical properties of 4-cyano-4′-pentylbiphenyl,” Jpn. J. Appl. Phys.48121404 (2009).
[CrossRef]

2008

W. -Y. Teng, S. -C. Jeng, C. -W. Kuo, Y. -R. Lin, C. -C. Liao, and W. -K. Chin, “Nanoparticles-doped guest-host liquid crystal displays,” Opt. Lett.33, 1663–1665 (2008).
[CrossRef] [PubMed]

S. -J. Hwang, S. -C. Jeng, C. -Y. Yang, C. -W. Kuo, and C. -C. Liao, “Characteristics of nanoparticle-doped homeotropic liquid crystal devices,” J. Phys. D: Appl. Phys.42,025102 (2008).
[CrossRef]

K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Polyimide photo-alignment layers for inclined homeotropic alignment of liquid crystal molecules,” Thin Solid Films516, 2652–2655 (2008).
[CrossRef]

2007

Y. J. Lee, Y. W. Kim, J. D. Ha, J. M. Oh, and M. H. Yi, “Synthesis and characterization of novel polyimides with 1-octadecyl side chains for liquid crystal alignment layers,” Polym. Adv. Technol.18, 226–234 (2007).
[CrossRef]

S. -C. Jeng, C. -W. Kuo, H. -L. Wang, and C. -C. Liao, “Nanoparticles-induced vertical alignment in liquid crystal cell,” Appl. Phys. Lett.91,061112 (2007).
[CrossRef]

2005

O. Haba, K. Okuyama, H. Osawa, and K. Yonetake, “Structures and properties of dendrimers having peripheral 2,3-difluorobiphenyl mesogenic units: effects of dendrimer generation,” Liq. Cryst.32, 633–642 (2005).
[CrossRef]

2004

A. H. Barber, S. R. Cohen, and H. D. Wagner, “Static and dynamic wetting measurements of single carbon nanotubes,” Phys. Rev. Lett.92,186103 (2004).
[CrossRef] [PubMed]

J. -M. Han, J. -Y. Hwang, D. -S. Seo, S. -K. Lee, and J. -U. Lee, “Washing effects on the anchoring energy and surface order parameter on rubbed polymer surfaces containing the trifluoromethyl moiety,” Liq. Cryst.31, 1259–1264 (2004).
[CrossRef]

M. Oh-e, H. Yokoyama, and D. Kim, “Mapping molecular conformation and orientation of polyimide surfaces for homeotropicliquid crystal alignment by nonlinear optical spectroscopy,” Phys. Rev. E.69,051705 (2004).
[CrossRef]

2003

J. -Y. Hwang, S. H. Lee, S. K. Paek, and D. -S. Seo, “Tilt angle generation for nematic liquid crystal on blended homeotropic polyimide layer containing trifluoromethyl moieties,” Jpn. J. Appl. Phys.42, 1713–1714 (2003).
[CrossRef]

2001

J. C. Jung, K. H. Lee, B. S. Sohn, S. W. Lee, and M. Ree, “Novel polypyromellitimides and their liquid crystal aligning properties,” Macromol. Symp.164, 227–238 (2001).
[CrossRef]

1999

K. Yonetake, T. Masuko, T. Morishita, K. Suzuki, M. Ueda, and R. Nagahata, “Poly(propyleneimine) dendrimers peripherally modified with mesogens,” Macromolecules32, 6578–6586 (1999).
[CrossRef]

1996

K. Lorenz, D. Hölter, B. Stühn, R. Mülhaupt, and H. Frey, “A mesogen-functionized carbosilane dendrimer: a dendritic liquid crystalline polymer,” Adv. Mater.8, 414–416 (1996).
[CrossRef]

M. G. Samant, J. Stöhr, H. R. Brown, T. P. Russell, J. M. Sands, and S. K. Kumar, “NEXAFS Studies on the surface orientation of buffed polyimides,” Macromolecules29, 8334–8342 (1996).
[CrossRef]

K. Shirota, M. Yaginuma, T. Sakai, K. Ishikawa, H. Takezoe, and A. Fukuda, “Surface orientation of cyanobiphenyl liquid crystal monolayer and pretilt angle under various rubbing strengths,” Jpn. J. Appl. Phys35, 2275–2279 (1996).
[CrossRef]

1995

V. Percec, P. Chu, G. Ungar, and J. Zhou, “Rational design of the first nonspherical dendrimer which displays calamitic nematic and smectic thermotropic liquid crystalline phases,” J. Am. Chem. Soc.117, 11441–11454 (1995).
[CrossRef]

1993

N. A. J. M. van Aerle, M. Barmentlo, and R. W. J. Hollering, “Effect of rubbing on the molecular orientation within polyimide orienting layers of liquid-crystal displays,” J. Appl. Phys.74, 3111–3120 (1993).
[CrossRef]

1992

D. -S. Seo, K. Muroi, and S. Kobayashi, “Generation of pretilt angles in nematic liquid crystal, 5CB, media aligned on polyimide films prepared by spin-coating and LB techniques: effect of rubbing,” Mol. Cryst. Liq. Cryst., Sci. Technol., A, Mol. Cryst. Liq. Cryst.213, 223–228 (1992).
[CrossRef]

Y. H. Kim, “Lyotropic liquid crystalline hyperbranched aromatic polyamides,” J. Am. Chem. Soc.114, 4947–4948 (1992).
[CrossRef]

Barber, A. H.

A. H. Barber, S. R. Cohen, and H. D. Wagner, “Static and dynamic wetting measurements of single carbon nanotubes,” Phys. Rev. Lett.92,186103 (2004).
[CrossRef] [PubMed]

Barmentlo, M.

N. A. J. M. van Aerle, M. Barmentlo, and R. W. J. Hollering, “Effect of rubbing on the molecular orientation within polyimide orienting layers of liquid-crystal displays,” J. Appl. Phys.74, 3111–3120 (1993).
[CrossRef]

Brown, H. R.

M. G. Samant, J. Stöhr, H. R. Brown, T. P. Russell, J. M. Sands, and S. K. Kumar, “NEXAFS Studies on the surface orientation of buffed polyimides,” Macromolecules29, 8334–8342 (1996).
[CrossRef]

Chin, W. -K.

W. -Y. Teng, S. -C. Jeng, J. -M. Ding, C. -W. Kuo, and W. -K. Chin, “Flexible homeotropic liquid crystal displays using low-glass-transition-temperature poly(ethylene terephthalate) substrates,” Jpn. J. Appl. Phys.49,010205 (2010).
[CrossRef]

W. -Y. Teng, S. -C. Jeng, C. -W. Kuo, Y. -R. Lin, C. -C. Liao, and W. -K. Chin, “Nanoparticles-doped guest-host liquid crystal displays,” Opt. Lett.33, 1663–1665 (2008).
[CrossRef] [PubMed]

Choi, D.

Y. Momoi, M. Kwak, D. Choi, Y. Choi, K. Jeong, T. Koda, O. Haba, and K. Yonetake, “Polyimide-free LCD by dissolving dendrimers,” J. Soc. Inf. Display.20, 486–492 (2012).
[CrossRef]

Choi, Y.

Y. Momoi, M. Kwak, D. Choi, Y. Choi, K. Jeong, T. Koda, O. Haba, and K. Yonetake, “Polyimide-free LCD by dissolving dendrimers,” J. Soc. Inf. Display.20, 486–492 (2012).
[CrossRef]

Chu, P.

V. Percec, P. Chu, G. Ungar, and J. Zhou, “Rational design of the first nonspherical dendrimer which displays calamitic nematic and smectic thermotropic liquid crystalline phases,” J. Am. Chem. Soc.117, 11441–11454 (1995).
[CrossRef]

Cohen, S. R.

A. H. Barber, S. R. Cohen, and H. D. Wagner, “Static and dynamic wetting measurements of single carbon nanotubes,” Phys. Rev. Lett.92,186103 (2004).
[CrossRef] [PubMed]

Ding, J. -M.

W. -Y. Teng, S. -C. Jeng, J. -M. Ding, C. -W. Kuo, and W. -K. Chin, “Flexible homeotropic liquid crystal displays using low-glass-transition-temperature poly(ethylene terephthalate) substrates,” Jpn. J. Appl. Phys.49,010205 (2010).
[CrossRef]

Fang, Y. -Q.

Y. -Q. Fang, J. Wang, Q. Zhang, Y. Zeng, and Y. -H. Wang, “Synthesis of soluble polyimides for vertical alignment of liquid crystal via one-step method,” Eur. Polym. J.46, 1163–1167 (2010).
[CrossRef]

Frey, H.

K. Lorenz, D. Hölter, B. Stühn, R. Mülhaupt, and H. Frey, “A mesogen-functionized carbosilane dendrimer: a dendritic liquid crystalline polymer,” Adv. Mater.8, 414–416 (1996).
[CrossRef]

Fukuda, A.

K. Shirota, M. Yaginuma, T. Sakai, K. Ishikawa, H. Takezoe, and A. Fukuda, “Surface orientation of cyanobiphenyl liquid crystal monolayer and pretilt angle under various rubbing strengths,” Jpn. J. Appl. Phys35, 2275–2279 (1996).
[CrossRef]

Furuta, K.

O. Haba, D. Hiratsuka, T. Shiraiwa, T. Koda, K. Yonetake, Y. Momoi, and K. Furuta, “Synthesis and characterization of polypropyleneimine dendrimers having peripheral mesogenic groups: homeotropic orientation and mesogen Structure,” Mol. Cryst. Liq. Cryst.574, 84–95 (2013).
[CrossRef]

Ha, J. D.

Y. J. Lee, Y. W. Kim, J. D. Ha, J. M. Oh, and M. H. Yi, “Synthesis and characterization of novel polyimides with 1-octadecyl side chains for liquid crystal alignment layers,” Polym. Adv. Technol.18, 226–234 (2007).
[CrossRef]

Haba, O.

O. Haba, D. Hiratsuka, T. Shiraiwa, T. Koda, K. Yonetake, Y. Momoi, and K. Furuta, “Synthesis and characterization of polypropyleneimine dendrimers having peripheral mesogenic groups: homeotropic orientation and mesogen Structure,” Mol. Cryst. Liq. Cryst.574, 84–95 (2013).
[CrossRef]

Y. Momoi, M. Kwak, D. Choi, Y. Choi, K. Jeong, T. Koda, O. Haba, and K. Yonetake, “Polyimide-free LCD by dissolving dendrimers,” J. Soc. Inf. Display.20, 486–492 (2012).
[CrossRef]

O. Haba, K. Okuyama, H. Osawa, and K. Yonetake, “Structures and properties of dendrimers having peripheral 2,3-difluorobiphenyl mesogenic units: effects of dendrimer generation,” Liq. Cryst.32, 633–642 (2005).
[CrossRef]

Han, J. -M.

J. -M. Han, J. -Y. Hwang, D. -S. Seo, S. -K. Lee, and J. -U. Lee, “Washing effects on the anchoring energy and surface order parameter on rubbed polymer surfaces containing the trifluoromethyl moiety,” Liq. Cryst.31, 1259–1264 (2004).
[CrossRef]

Hashimoto, Y.

M. Nakamura, Y. Hashimoto, T. Shinomiya, and S. Mizushima, “Liquid crystal display device,” US Patent, US7719656 B2 (2006).

Hiratsuka, D.

O. Haba, D. Hiratsuka, T. Shiraiwa, T. Koda, K. Yonetake, Y. Momoi, and K. Furuta, “Synthesis and characterization of polypropyleneimine dendrimers having peripheral mesogenic groups: homeotropic orientation and mesogen Structure,” Mol. Cryst. Liq. Cryst.574, 84–95 (2013).
[CrossRef]

Hollering, R. W. J.

N. A. J. M. van Aerle, M. Barmentlo, and R. W. J. Hollering, “Effect of rubbing on the molecular orientation within polyimide orienting layers of liquid-crystal displays,” J. Appl. Phys.74, 3111–3120 (1993).
[CrossRef]

Hölter, D.

K. Lorenz, D. Hölter, B. Stühn, R. Mülhaupt, and H. Frey, “A mesogen-functionized carbosilane dendrimer: a dendritic liquid crystalline polymer,” Adv. Mater.8, 414–416 (1996).
[CrossRef]

Hwang, J. -Y.

J. -M. Han, J. -Y. Hwang, D. -S. Seo, S. -K. Lee, and J. -U. Lee, “Washing effects on the anchoring energy and surface order parameter on rubbed polymer surfaces containing the trifluoromethyl moiety,” Liq. Cryst.31, 1259–1264 (2004).
[CrossRef]

J. -Y. Hwang, S. H. Lee, S. K. Paek, and D. -S. Seo, “Tilt angle generation for nematic liquid crystal on blended homeotropic polyimide layer containing trifluoromethyl moieties,” Jpn. J. Appl. Phys.42, 1713–1714 (2003).
[CrossRef]

Hwang, S. -J.

S. -J. Hwang, S. -C. Jeng, C. -Y. Yang, C. -W. Kuo, and C. -C. Liao, “Characteristics of nanoparticle-doped homeotropic liquid crystal devices,” J. Phys. D: Appl. Phys.42,025102 (2008).
[CrossRef]

Ikeda, S.

T. Koda, T. Mitsuyoshi, A. Kanazawa, A. Nishioka, K. Miyata, G. Murasawa, S. Ikeda, T. Miura, and Y. Kimura, “Effect of charge transfer complex on electrical properties of 4-cyano-4′-pentylbiphenyl,” Jpn. J. Appl. Phys.48121404 (2009).
[CrossRef]

Ishikawa, K.

K. Shirota, M. Yaginuma, T. Sakai, K. Ishikawa, H. Takezoe, and A. Fukuda, “Surface orientation of cyanobiphenyl liquid crystal monolayer and pretilt angle under various rubbing strengths,” Jpn. J. Appl. Phys35, 2275–2279 (1996).
[CrossRef]

Jeng, S. -C.

W. -Y. Teng, S. -C. Jeng, J. -M. Ding, C. -W. Kuo, and W. -K. Chin, “Flexible homeotropic liquid crystal displays using low-glass-transition-temperature poly(ethylene terephthalate) substrates,” Jpn. J. Appl. Phys.49,010205 (2010).
[CrossRef]

W. -Y. Teng, S. -C. Jeng, C. -W. Kuo, Y. -R. Lin, C. -C. Liao, and W. -K. Chin, “Nanoparticles-doped guest-host liquid crystal displays,” Opt. Lett.33, 1663–1665 (2008).
[CrossRef] [PubMed]

S. -J. Hwang, S. -C. Jeng, C. -Y. Yang, C. -W. Kuo, and C. -C. Liao, “Characteristics of nanoparticle-doped homeotropic liquid crystal devices,” J. Phys. D: Appl. Phys.42,025102 (2008).
[CrossRef]

S. -C. Jeng, C. -W. Kuo, H. -L. Wang, and C. -C. Liao, “Nanoparticles-induced vertical alignment in liquid crystal cell,” Appl. Phys. Lett.91,061112 (2007).
[CrossRef]

Jeong, K.

Y. Momoi, M. Kwak, D. Choi, Y. Choi, K. Jeong, T. Koda, O. Haba, and K. Yonetake, “Polyimide-free LCD by dissolving dendrimers,” J. Soc. Inf. Display.20, 486–492 (2012).
[CrossRef]

Jung, J. C.

J. C. Jung, K. H. Lee, B. S. Sohn, S. W. Lee, and M. Ree, “Novel polypyromellitimides and their liquid crystal aligning properties,” Macromol. Symp.164, 227–238 (2001).
[CrossRef]

Kanazawa, A.

T. Koda, T. Mitsuyoshi, A. Kanazawa, A. Nishioka, K. Miyata, G. Murasawa, S. Ikeda, T. Miura, and Y. Kimura, “Effect of charge transfer complex on electrical properties of 4-cyano-4′-pentylbiphenyl,” Jpn. J. Appl. Phys.48121404 (2009).
[CrossRef]

Kim, D.

M. Oh-e, H. Yokoyama, and D. Kim, “Mapping molecular conformation and orientation of polyimide surfaces for homeotropicliquid crystal alignment by nonlinear optical spectroscopy,” Phys. Rev. E.69,051705 (2004).
[CrossRef]

Kim, Y. H.

Y. H. Kim, “Lyotropic liquid crystalline hyperbranched aromatic polyamides,” J. Am. Chem. Soc.114, 4947–4948 (1992).
[CrossRef]

Kim, Y. W.

Y. J. Lee, Y. W. Kim, J. D. Ha, J. M. Oh, and M. H. Yi, “Synthesis and characterization of novel polyimides with 1-octadecyl side chains for liquid crystal alignment layers,” Polym. Adv. Technol.18, 226–234 (2007).
[CrossRef]

Kimura, Y.

T. Koda, T. Mitsuyoshi, A. Kanazawa, A. Nishioka, K. Miyata, G. Murasawa, S. Ikeda, T. Miura, and Y. Kimura, “Effect of charge transfer complex on electrical properties of 4-cyano-4′-pentylbiphenyl,” Jpn. J. Appl. Phys.48121404 (2009).
[CrossRef]

Kobayashi, S.

D. -S. Seo, K. Muroi, and S. Kobayashi, “Generation of pretilt angles in nematic liquid crystal, 5CB, media aligned on polyimide films prepared by spin-coating and LB techniques: effect of rubbing,” Mol. Cryst. Liq. Cryst., Sci. Technol., A, Mol. Cryst. Liq. Cryst.213, 223–228 (1992).
[CrossRef]

Koda, T.

O. Haba, D. Hiratsuka, T. Shiraiwa, T. Koda, K. Yonetake, Y. Momoi, and K. Furuta, “Synthesis and characterization of polypropyleneimine dendrimers having peripheral mesogenic groups: homeotropic orientation and mesogen Structure,” Mol. Cryst. Liq. Cryst.574, 84–95 (2013).
[CrossRef]

Y. Momoi, M. Kwak, D. Choi, Y. Choi, K. Jeong, T. Koda, O. Haba, and K. Yonetake, “Polyimide-free LCD by dissolving dendrimers,” J. Soc. Inf. Display.20, 486–492 (2012).
[CrossRef]

T. Koda, T. Mitsuyoshi, A. Kanazawa, A. Nishioka, K. Miyata, G. Murasawa, S. Ikeda, T. Miura, and Y. Kimura, “Effect of charge transfer complex on electrical properties of 4-cyano-4′-pentylbiphenyl,” Jpn. J. Appl. Phys.48121404 (2009).
[CrossRef]

Kumar, S. K.

M. G. Samant, J. Stöhr, H. R. Brown, T. P. Russell, J. M. Sands, and S. K. Kumar, “NEXAFS Studies on the surface orientation of buffed polyimides,” Macromolecules29, 8334–8342 (1996).
[CrossRef]

Kuo, C. -W.

W. -Y. Teng, S. -C. Jeng, J. -M. Ding, C. -W. Kuo, and W. -K. Chin, “Flexible homeotropic liquid crystal displays using low-glass-transition-temperature poly(ethylene terephthalate) substrates,” Jpn. J. Appl. Phys.49,010205 (2010).
[CrossRef]

W. -Y. Teng, S. -C. Jeng, C. -W. Kuo, Y. -R. Lin, C. -C. Liao, and W. -K. Chin, “Nanoparticles-doped guest-host liquid crystal displays,” Opt. Lett.33, 1663–1665 (2008).
[CrossRef] [PubMed]

S. -J. Hwang, S. -C. Jeng, C. -Y. Yang, C. -W. Kuo, and C. -C. Liao, “Characteristics of nanoparticle-doped homeotropic liquid crystal devices,” J. Phys. D: Appl. Phys.42,025102 (2008).
[CrossRef]

S. -C. Jeng, C. -W. Kuo, H. -L. Wang, and C. -C. Liao, “Nanoparticles-induced vertical alignment in liquid crystal cell,” Appl. Phys. Lett.91,061112 (2007).
[CrossRef]

Kwak, M.

Y. Momoi, M. Kwak, D. Choi, Y. Choi, K. Jeong, T. Koda, O. Haba, and K. Yonetake, “Polyimide-free LCD by dissolving dendrimers,” J. Soc. Inf. Display.20, 486–492 (2012).
[CrossRef]

Lee, J. -U.

J. -M. Han, J. -Y. Hwang, D. -S. Seo, S. -K. Lee, and J. -U. Lee, “Washing effects on the anchoring energy and surface order parameter on rubbed polymer surfaces containing the trifluoromethyl moiety,” Liq. Cryst.31, 1259–1264 (2004).
[CrossRef]

Lee, K. H.

J. C. Jung, K. H. Lee, B. S. Sohn, S. W. Lee, and M. Ree, “Novel polypyromellitimides and their liquid crystal aligning properties,” Macromol. Symp.164, 227–238 (2001).
[CrossRef]

Lee, S. H.

J. -Y. Hwang, S. H. Lee, S. K. Paek, and D. -S. Seo, “Tilt angle generation for nematic liquid crystal on blended homeotropic polyimide layer containing trifluoromethyl moieties,” Jpn. J. Appl. Phys.42, 1713–1714 (2003).
[CrossRef]

Lee, S. -K.

J. -M. Han, J. -Y. Hwang, D. -S. Seo, S. -K. Lee, and J. -U. Lee, “Washing effects on the anchoring energy and surface order parameter on rubbed polymer surfaces containing the trifluoromethyl moiety,” Liq. Cryst.31, 1259–1264 (2004).
[CrossRef]

Lee, S. W.

J. C. Jung, K. H. Lee, B. S. Sohn, S. W. Lee, and M. Ree, “Novel polypyromellitimides and their liquid crystal aligning properties,” Macromol. Symp.164, 227–238 (2001).
[CrossRef]

Lee, Y. J.

Y. J. Lee, Y. W. Kim, J. D. Ha, J. M. Oh, and M. H. Yi, “Synthesis and characterization of novel polyimides with 1-octadecyl side chains for liquid crystal alignment layers,” Polym. Adv. Technol.18, 226–234 (2007).
[CrossRef]

Liao, C. -C.

W. -Y. Teng, S. -C. Jeng, C. -W. Kuo, Y. -R. Lin, C. -C. Liao, and W. -K. Chin, “Nanoparticles-doped guest-host liquid crystal displays,” Opt. Lett.33, 1663–1665 (2008).
[CrossRef] [PubMed]

S. -J. Hwang, S. -C. Jeng, C. -Y. Yang, C. -W. Kuo, and C. -C. Liao, “Characteristics of nanoparticle-doped homeotropic liquid crystal devices,” J. Phys. D: Appl. Phys.42,025102 (2008).
[CrossRef]

S. -C. Jeng, C. -W. Kuo, H. -L. Wang, and C. -C. Liao, “Nanoparticles-induced vertical alignment in liquid crystal cell,” Appl. Phys. Lett.91,061112 (2007).
[CrossRef]

Lin, Y. -R.

Lorenz, K.

K. Lorenz, D. Hölter, B. Stühn, R. Mülhaupt, and H. Frey, “A mesogen-functionized carbosilane dendrimer: a dendritic liquid crystalline polymer,” Adv. Mater.8, 414–416 (1996).
[CrossRef]

Masuko, T.

K. Yonetake, T. Masuko, T. Morishita, K. Suzuki, M. Ueda, and R. Nagahata, “Poly(propyleneimine) dendrimers peripherally modified with mesogens,” Macromolecules32, 6578–6586 (1999).
[CrossRef]

Mitsuyoshi, T.

T. Koda, T. Mitsuyoshi, A. Kanazawa, A. Nishioka, K. Miyata, G. Murasawa, S. Ikeda, T. Miura, and Y. Kimura, “Effect of charge transfer complex on electrical properties of 4-cyano-4′-pentylbiphenyl,” Jpn. J. Appl. Phys.48121404 (2009).
[CrossRef]

Miura, T.

T. Koda, T. Mitsuyoshi, A. Kanazawa, A. Nishioka, K. Miyata, G. Murasawa, S. Ikeda, T. Miura, and Y. Kimura, “Effect of charge transfer complex on electrical properties of 4-cyano-4′-pentylbiphenyl,” Jpn. J. Appl. Phys.48121404 (2009).
[CrossRef]

Miyata, K.

T. Koda, T. Mitsuyoshi, A. Kanazawa, A. Nishioka, K. Miyata, G. Murasawa, S. Ikeda, T. Miura, and Y. Kimura, “Effect of charge transfer complex on electrical properties of 4-cyano-4′-pentylbiphenyl,” Jpn. J. Appl. Phys.48121404 (2009).
[CrossRef]

Mizushima, S.

M. Nakamura, Y. Hashimoto, T. Shinomiya, and S. Mizushima, “Liquid crystal display device,” US Patent, US7719656 B2 (2006).

Momoi, Y.

O. Haba, D. Hiratsuka, T. Shiraiwa, T. Koda, K. Yonetake, Y. Momoi, and K. Furuta, “Synthesis and characterization of polypropyleneimine dendrimers having peripheral mesogenic groups: homeotropic orientation and mesogen Structure,” Mol. Cryst. Liq. Cryst.574, 84–95 (2013).
[CrossRef]

Y. Momoi, M. Kwak, D. Choi, Y. Choi, K. Jeong, T. Koda, O. Haba, and K. Yonetake, “Polyimide-free LCD by dissolving dendrimers,” J. Soc. Inf. Display.20, 486–492 (2012).
[CrossRef]

Morishita, T.

K. Yonetake, T. Masuko, T. Morishita, K. Suzuki, M. Ueda, and R. Nagahata, “Poly(propyleneimine) dendrimers peripherally modified with mesogens,” Macromolecules32, 6578–6586 (1999).
[CrossRef]

Mülhaupt, R.

K. Lorenz, D. Hölter, B. Stühn, R. Mülhaupt, and H. Frey, “A mesogen-functionized carbosilane dendrimer: a dendritic liquid crystalline polymer,” Adv. Mater.8, 414–416 (1996).
[CrossRef]

Murasawa, G.

T. Koda, T. Mitsuyoshi, A. Kanazawa, A. Nishioka, K. Miyata, G. Murasawa, S. Ikeda, T. Miura, and Y. Kimura, “Effect of charge transfer complex on electrical properties of 4-cyano-4′-pentylbiphenyl,” Jpn. J. Appl. Phys.48121404 (2009).
[CrossRef]

Muroi, K.

D. -S. Seo, K. Muroi, and S. Kobayashi, “Generation of pretilt angles in nematic liquid crystal, 5CB, media aligned on polyimide films prepared by spin-coating and LB techniques: effect of rubbing,” Mol. Cryst. Liq. Cryst., Sci. Technol., A, Mol. Cryst. Liq. Cryst.213, 223–228 (1992).
[CrossRef]

Nagahata, R.

K. Yonetake, T. Masuko, T. Morishita, K. Suzuki, M. Ueda, and R. Nagahata, “Poly(propyleneimine) dendrimers peripherally modified with mesogens,” Macromolecules32, 6578–6586 (1999).
[CrossRef]

Nakamura, M.

M. Nakamura, Y. Hashimoto, T. Shinomiya, and S. Mizushima, “Liquid crystal display device,” US Patent, US7719656 B2 (2006).

Nishioka, A.

T. Koda, T. Mitsuyoshi, A. Kanazawa, A. Nishioka, K. Miyata, G. Murasawa, S. Ikeda, T. Miura, and Y. Kimura, “Effect of charge transfer complex on electrical properties of 4-cyano-4′-pentylbiphenyl,” Jpn. J. Appl. Phys.48121404 (2009).
[CrossRef]

Oh, J. M.

Y. J. Lee, Y. W. Kim, J. D. Ha, J. M. Oh, and M. H. Yi, “Synthesis and characterization of novel polyimides with 1-octadecyl side chains for liquid crystal alignment layers,” Polym. Adv. Technol.18, 226–234 (2007).
[CrossRef]

Oh-e, M.

M. Oh-e, H. Yokoyama, and D. Kim, “Mapping molecular conformation and orientation of polyimide surfaces for homeotropicliquid crystal alignment by nonlinear optical spectroscopy,” Phys. Rev. E.69,051705 (2004).
[CrossRef]

Okuyama, K.

O. Haba, K. Okuyama, H. Osawa, and K. Yonetake, “Structures and properties of dendrimers having peripheral 2,3-difluorobiphenyl mesogenic units: effects of dendrimer generation,” Liq. Cryst.32, 633–642 (2005).
[CrossRef]

Osawa, H.

O. Haba, K. Okuyama, H. Osawa, and K. Yonetake, “Structures and properties of dendrimers having peripheral 2,3-difluorobiphenyl mesogenic units: effects of dendrimer generation,” Liq. Cryst.32, 633–642 (2005).
[CrossRef]

Owens, D. K.

D. K. Owens and R. C. Wendt, “Estimation of the surface free energy of polymers,” 12, 1741–1747 (1969).

Paek, S. K.

J. -Y. Hwang, S. H. Lee, S. K. Paek, and D. -S. Seo, “Tilt angle generation for nematic liquid crystal on blended homeotropic polyimide layer containing trifluoromethyl moieties,” Jpn. J. Appl. Phys.42, 1713–1714 (2003).
[CrossRef]

Percec, V.

V. Percec, P. Chu, G. Ungar, and J. Zhou, “Rational design of the first nonspherical dendrimer which displays calamitic nematic and smectic thermotropic liquid crystalline phases,” J. Am. Chem. Soc.117, 11441–11454 (1995).
[CrossRef]

Ree, M.

J. C. Jung, K. H. Lee, B. S. Sohn, S. W. Lee, and M. Ree, “Novel polypyromellitimides and their liquid crystal aligning properties,” Macromol. Symp.164, 227–238 (2001).
[CrossRef]

Russell, T. P.

M. G. Samant, J. Stöhr, H. R. Brown, T. P. Russell, J. M. Sands, and S. K. Kumar, “NEXAFS Studies on the surface orientation of buffed polyimides,” Macromolecules29, 8334–8342 (1996).
[CrossRef]

Sakai, T.

K. Shirota, M. Yaginuma, T. Sakai, K. Ishikawa, H. Takezoe, and A. Fukuda, “Surface orientation of cyanobiphenyl liquid crystal monolayer and pretilt angle under various rubbing strengths,” Jpn. J. Appl. Phys35, 2275–2279 (1996).
[CrossRef]

Sakamoto, K.

K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Polyimide photo-alignment layers for inclined homeotropic alignment of liquid crystal molecules,” Thin Solid Films516, 2652–2655 (2008).
[CrossRef]

Samant, M. G.

M. G. Samant, J. Stöhr, H. R. Brown, T. P. Russell, J. M. Sands, and S. K. Kumar, “NEXAFS Studies on the surface orientation of buffed polyimides,” Macromolecules29, 8334–8342 (1996).
[CrossRef]

Sands, J. M.

M. G. Samant, J. Stöhr, H. R. Brown, T. P. Russell, J. M. Sands, and S. K. Kumar, “NEXAFS Studies on the surface orientation of buffed polyimides,” Macromolecules29, 8334–8342 (1996).
[CrossRef]

Seo, D. -S.

J. -M. Han, J. -Y. Hwang, D. -S. Seo, S. -K. Lee, and J. -U. Lee, “Washing effects on the anchoring energy and surface order parameter on rubbed polymer surfaces containing the trifluoromethyl moiety,” Liq. Cryst.31, 1259–1264 (2004).
[CrossRef]

J. -Y. Hwang, S. H. Lee, S. K. Paek, and D. -S. Seo, “Tilt angle generation for nematic liquid crystal on blended homeotropic polyimide layer containing trifluoromethyl moieties,” Jpn. J. Appl. Phys.42, 1713–1714 (2003).
[CrossRef]

D. -S. Seo, K. Muroi, and S. Kobayashi, “Generation of pretilt angles in nematic liquid crystal, 5CB, media aligned on polyimide films prepared by spin-coating and LB techniques: effect of rubbing,” Mol. Cryst. Liq. Cryst., Sci. Technol., A, Mol. Cryst. Liq. Cryst.213, 223–228 (1992).
[CrossRef]

Shinomiya, T.

M. Nakamura, Y. Hashimoto, T. Shinomiya, and S. Mizushima, “Liquid crystal display device,” US Patent, US7719656 B2 (2006).

Shiraiwa, T.

O. Haba, D. Hiratsuka, T. Shiraiwa, T. Koda, K. Yonetake, Y. Momoi, and K. Furuta, “Synthesis and characterization of polypropyleneimine dendrimers having peripheral mesogenic groups: homeotropic orientation and mesogen Structure,” Mol. Cryst. Liq. Cryst.574, 84–95 (2013).
[CrossRef]

Shirota, K.

K. Shirota, M. Yaginuma, T. Sakai, K. Ishikawa, H. Takezoe, and A. Fukuda, “Surface orientation of cyanobiphenyl liquid crystal monolayer and pretilt angle under various rubbing strengths,” Jpn. J. Appl. Phys35, 2275–2279 (1996).
[CrossRef]

Sohn, B. S.

J. C. Jung, K. H. Lee, B. S. Sohn, S. W. Lee, and M. Ree, “Novel polypyromellitimides and their liquid crystal aligning properties,” Macromol. Symp.164, 227–238 (2001).
[CrossRef]

Stöhr, J.

M. G. Samant, J. Stöhr, H. R. Brown, T. P. Russell, J. M. Sands, and S. K. Kumar, “NEXAFS Studies on the surface orientation of buffed polyimides,” Macromolecules29, 8334–8342 (1996).
[CrossRef]

Stühn, B.

K. Lorenz, D. Hölter, B. Stühn, R. Mülhaupt, and H. Frey, “A mesogen-functionized carbosilane dendrimer: a dendritic liquid crystalline polymer,” Adv. Mater.8, 414–416 (1996).
[CrossRef]

Suzuki, K.

K. Yonetake, T. Masuko, T. Morishita, K. Suzuki, M. Ueda, and R. Nagahata, “Poly(propyleneimine) dendrimers peripherally modified with mesogens,” Macromolecules32, 6578–6586 (1999).
[CrossRef]

Takezoe, H.

K. Shirota, M. Yaginuma, T. Sakai, K. Ishikawa, H. Takezoe, and A. Fukuda, “Surface orientation of cyanobiphenyl liquid crystal monolayer and pretilt angle under various rubbing strengths,” Jpn. J. Appl. Phys35, 2275–2279 (1996).
[CrossRef]

Teng, W. -Y.

W. -Y. Teng, S. -C. Jeng, J. -M. Ding, C. -W. Kuo, and W. -K. Chin, “Flexible homeotropic liquid crystal displays using low-glass-transition-temperature poly(ethylene terephthalate) substrates,” Jpn. J. Appl. Phys.49,010205 (2010).
[CrossRef]

W. -Y. Teng, S. -C. Jeng, C. -W. Kuo, Y. -R. Lin, C. -C. Liao, and W. -K. Chin, “Nanoparticles-doped guest-host liquid crystal displays,” Opt. Lett.33, 1663–1665 (2008).
[CrossRef] [PubMed]

Ueda, M.

K. Yonetake, T. Masuko, T. Morishita, K. Suzuki, M. Ueda, and R. Nagahata, “Poly(propyleneimine) dendrimers peripherally modified with mesogens,” Macromolecules32, 6578–6586 (1999).
[CrossRef]

Uehara, Y.

K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Polyimide photo-alignment layers for inclined homeotropic alignment of liquid crystal molecules,” Thin Solid Films516, 2652–2655 (2008).
[CrossRef]

Ungar, G.

V. Percec, P. Chu, G. Ungar, and J. Zhou, “Rational design of the first nonspherical dendrimer which displays calamitic nematic and smectic thermotropic liquid crystalline phases,” J. Am. Chem. Soc.117, 11441–11454 (1995).
[CrossRef]

Usami, K.

K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Polyimide photo-alignment layers for inclined homeotropic alignment of liquid crystal molecules,” Thin Solid Films516, 2652–2655 (2008).
[CrossRef]

Ushioda, S.

K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Polyimide photo-alignment layers for inclined homeotropic alignment of liquid crystal molecules,” Thin Solid Films516, 2652–2655 (2008).
[CrossRef]

van Aerle, N. A. J. M.

N. A. J. M. van Aerle, M. Barmentlo, and R. W. J. Hollering, “Effect of rubbing on the molecular orientation within polyimide orienting layers of liquid-crystal displays,” J. Appl. Phys.74, 3111–3120 (1993).
[CrossRef]

Wagner, H. D.

A. H. Barber, S. R. Cohen, and H. D. Wagner, “Static and dynamic wetting measurements of single carbon nanotubes,” Phys. Rev. Lett.92,186103 (2004).
[CrossRef] [PubMed]

Wang, H. -L.

S. -C. Jeng, C. -W. Kuo, H. -L. Wang, and C. -C. Liao, “Nanoparticles-induced vertical alignment in liquid crystal cell,” Appl. Phys. Lett.91,061112 (2007).
[CrossRef]

Wang, J.

Y. -Q. Fang, J. Wang, Q. Zhang, Y. Zeng, and Y. -H. Wang, “Synthesis of soluble polyimides for vertical alignment of liquid crystal via one-step method,” Eur. Polym. J.46, 1163–1167 (2010).
[CrossRef]

Wang, Y. -H.

Y. -Q. Fang, J. Wang, Q. Zhang, Y. Zeng, and Y. -H. Wang, “Synthesis of soluble polyimides for vertical alignment of liquid crystal via one-step method,” Eur. Polym. J.46, 1163–1167 (2010).
[CrossRef]

Wendt, R. C.

D. K. Owens and R. C. Wendt, “Estimation of the surface free energy of polymers,” 12, 1741–1747 (1969).

Yaginuma, M.

K. Shirota, M. Yaginuma, T. Sakai, K. Ishikawa, H. Takezoe, and A. Fukuda, “Surface orientation of cyanobiphenyl liquid crystal monolayer and pretilt angle under various rubbing strengths,” Jpn. J. Appl. Phys35, 2275–2279 (1996).
[CrossRef]

Yang, C. -Y.

S. -J. Hwang, S. -C. Jeng, C. -Y. Yang, C. -W. Kuo, and C. -C. Liao, “Characteristics of nanoparticle-doped homeotropic liquid crystal devices,” J. Phys. D: Appl. Phys.42,025102 (2008).
[CrossRef]

Yi, M. H.

Y. J. Lee, Y. W. Kim, J. D. Ha, J. M. Oh, and M. H. Yi, “Synthesis and characterization of novel polyimides with 1-octadecyl side chains for liquid crystal alignment layers,” Polym. Adv. Technol.18, 226–234 (2007).
[CrossRef]

Yokota, J.

K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Polyimide photo-alignment layers for inclined homeotropic alignment of liquid crystal molecules,” Thin Solid Films516, 2652–2655 (2008).
[CrossRef]

Yokoyama, H.

M. Oh-e, H. Yokoyama, and D. Kim, “Mapping molecular conformation and orientation of polyimide surfaces for homeotropicliquid crystal alignment by nonlinear optical spectroscopy,” Phys. Rev. E.69,051705 (2004).
[CrossRef]

Yonetake, K.

O. Haba, D. Hiratsuka, T. Shiraiwa, T. Koda, K. Yonetake, Y. Momoi, and K. Furuta, “Synthesis and characterization of polypropyleneimine dendrimers having peripheral mesogenic groups: homeotropic orientation and mesogen Structure,” Mol. Cryst. Liq. Cryst.574, 84–95 (2013).
[CrossRef]

Y. Momoi, M. Kwak, D. Choi, Y. Choi, K. Jeong, T. Koda, O. Haba, and K. Yonetake, “Polyimide-free LCD by dissolving dendrimers,” J. Soc. Inf. Display.20, 486–492 (2012).
[CrossRef]

O. Haba, K. Okuyama, H. Osawa, and K. Yonetake, “Structures and properties of dendrimers having peripheral 2,3-difluorobiphenyl mesogenic units: effects of dendrimer generation,” Liq. Cryst.32, 633–642 (2005).
[CrossRef]

K. Yonetake, T. Masuko, T. Morishita, K. Suzuki, M. Ueda, and R. Nagahata, “Poly(propyleneimine) dendrimers peripherally modified with mesogens,” Macromolecules32, 6578–6586 (1999).
[CrossRef]

Zeng, Y.

Y. -Q. Fang, J. Wang, Q. Zhang, Y. Zeng, and Y. -H. Wang, “Synthesis of soluble polyimides for vertical alignment of liquid crystal via one-step method,” Eur. Polym. J.46, 1163–1167 (2010).
[CrossRef]

Zhang, Q.

Y. -Q. Fang, J. Wang, Q. Zhang, Y. Zeng, and Y. -H. Wang, “Synthesis of soluble polyimides for vertical alignment of liquid crystal via one-step method,” Eur. Polym. J.46, 1163–1167 (2010).
[CrossRef]

Zhou, J.

V. Percec, P. Chu, G. Ungar, and J. Zhou, “Rational design of the first nonspherical dendrimer which displays calamitic nematic and smectic thermotropic liquid crystalline phases,” J. Am. Chem. Soc.117, 11441–11454 (1995).
[CrossRef]

Adv. Mater.

K. Lorenz, D. Hölter, B. Stühn, R. Mülhaupt, and H. Frey, “A mesogen-functionized carbosilane dendrimer: a dendritic liquid crystalline polymer,” Adv. Mater.8, 414–416 (1996).
[CrossRef]

Appl. Phys. Lett.

S. -C. Jeng, C. -W. Kuo, H. -L. Wang, and C. -C. Liao, “Nanoparticles-induced vertical alignment in liquid crystal cell,” Appl. Phys. Lett.91,061112 (2007).
[CrossRef]

Eur. Polym. J.

Y. -Q. Fang, J. Wang, Q. Zhang, Y. Zeng, and Y. -H. Wang, “Synthesis of soluble polyimides for vertical alignment of liquid crystal via one-step method,” Eur. Polym. J.46, 1163–1167 (2010).
[CrossRef]

J. Am. Chem. Soc.

Y. H. Kim, “Lyotropic liquid crystalline hyperbranched aromatic polyamides,” J. Am. Chem. Soc.114, 4947–4948 (1992).
[CrossRef]

V. Percec, P. Chu, G. Ungar, and J. Zhou, “Rational design of the first nonspherical dendrimer which displays calamitic nematic and smectic thermotropic liquid crystalline phases,” J. Am. Chem. Soc.117, 11441–11454 (1995).
[CrossRef]

J. Appl. Phys.

N. A. J. M. van Aerle, M. Barmentlo, and R. W. J. Hollering, “Effect of rubbing on the molecular orientation within polyimide orienting layers of liquid-crystal displays,” J. Appl. Phys.74, 3111–3120 (1993).
[CrossRef]

J. Phys. D: Appl. Phys.

S. -J. Hwang, S. -C. Jeng, C. -Y. Yang, C. -W. Kuo, and C. -C. Liao, “Characteristics of nanoparticle-doped homeotropic liquid crystal devices,” J. Phys. D: Appl. Phys.42,025102 (2008).
[CrossRef]

J. Soc. Inf. Display.

Y. Momoi, M. Kwak, D. Choi, Y. Choi, K. Jeong, T. Koda, O. Haba, and K. Yonetake, “Polyimide-free LCD by dissolving dendrimers,” J. Soc. Inf. Display.20, 486–492 (2012).
[CrossRef]

Jpn. J. Appl. Phys

K. Shirota, M. Yaginuma, T. Sakai, K. Ishikawa, H. Takezoe, and A. Fukuda, “Surface orientation of cyanobiphenyl liquid crystal monolayer and pretilt angle under various rubbing strengths,” Jpn. J. Appl. Phys35, 2275–2279 (1996).
[CrossRef]

Jpn. J. Appl. Phys.

J. -Y. Hwang, S. H. Lee, S. K. Paek, and D. -S. Seo, “Tilt angle generation for nematic liquid crystal on blended homeotropic polyimide layer containing trifluoromethyl moieties,” Jpn. J. Appl. Phys.42, 1713–1714 (2003).
[CrossRef]

W. -Y. Teng, S. -C. Jeng, J. -M. Ding, C. -W. Kuo, and W. -K. Chin, “Flexible homeotropic liquid crystal displays using low-glass-transition-temperature poly(ethylene terephthalate) substrates,” Jpn. J. Appl. Phys.49,010205 (2010).
[CrossRef]

T. Koda, T. Mitsuyoshi, A. Kanazawa, A. Nishioka, K. Miyata, G. Murasawa, S. Ikeda, T. Miura, and Y. Kimura, “Effect of charge transfer complex on electrical properties of 4-cyano-4′-pentylbiphenyl,” Jpn. J. Appl. Phys.48121404 (2009).
[CrossRef]

Liq. Cryst.

O. Haba, K. Okuyama, H. Osawa, and K. Yonetake, “Structures and properties of dendrimers having peripheral 2,3-difluorobiphenyl mesogenic units: effects of dendrimer generation,” Liq. Cryst.32, 633–642 (2005).
[CrossRef]

J. -M. Han, J. -Y. Hwang, D. -S. Seo, S. -K. Lee, and J. -U. Lee, “Washing effects on the anchoring energy and surface order parameter on rubbed polymer surfaces containing the trifluoromethyl moiety,” Liq. Cryst.31, 1259–1264 (2004).
[CrossRef]

Macromol. Symp.

J. C. Jung, K. H. Lee, B. S. Sohn, S. W. Lee, and M. Ree, “Novel polypyromellitimides and their liquid crystal aligning properties,” Macromol. Symp.164, 227–238 (2001).
[CrossRef]

Macromolecules

M. G. Samant, J. Stöhr, H. R. Brown, T. P. Russell, J. M. Sands, and S. K. Kumar, “NEXAFS Studies on the surface orientation of buffed polyimides,” Macromolecules29, 8334–8342 (1996).
[CrossRef]

K. Yonetake, T. Masuko, T. Morishita, K. Suzuki, M. Ueda, and R. Nagahata, “Poly(propyleneimine) dendrimers peripherally modified with mesogens,” Macromolecules32, 6578–6586 (1999).
[CrossRef]

Mol. Cryst. Liq. Cryst.

O. Haba, D. Hiratsuka, T. Shiraiwa, T. Koda, K. Yonetake, Y. Momoi, and K. Furuta, “Synthesis and characterization of polypropyleneimine dendrimers having peripheral mesogenic groups: homeotropic orientation and mesogen Structure,” Mol. Cryst. Liq. Cryst.574, 84–95 (2013).
[CrossRef]

Mol. Cryst. Liq. Cryst., Sci. Technol., A, Mol. Cryst. Liq. Cryst.

D. -S. Seo, K. Muroi, and S. Kobayashi, “Generation of pretilt angles in nematic liquid crystal, 5CB, media aligned on polyimide films prepared by spin-coating and LB techniques: effect of rubbing,” Mol. Cryst. Liq. Cryst., Sci. Technol., A, Mol. Cryst. Liq. Cryst.213, 223–228 (1992).
[CrossRef]

Opt. Lett.

Phys. Rev. E.

M. Oh-e, H. Yokoyama, and D. Kim, “Mapping molecular conformation and orientation of polyimide surfaces for homeotropicliquid crystal alignment by nonlinear optical spectroscopy,” Phys. Rev. E.69,051705 (2004).
[CrossRef]

Phys. Rev. Lett.

A. H. Barber, S. R. Cohen, and H. D. Wagner, “Static and dynamic wetting measurements of single carbon nanotubes,” Phys. Rev. Lett.92,186103 (2004).
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Figures (8)

Fig. 1
Fig. 1

Structure of the LC dendrimers used in this study.

Fig. 2
Fig. 2

Schematic representation of LC cell used in this study. It was assembled with a bare glass substrate and a glass substrate with an interdigitated Cr electrode.

Fig. 3
Fig. 3

POM images of D-6PPCN/5CB (1/99, wt/wt) mixture during (a–c) heating at 10 °C·min−1, and (d–g) cooling at −1 °C·min−1.

Fig. 4
Fig. 4

POM images of the dendrimer/NLC (1/99, wt/wt) mixture between the bare glasses at room temperature after heating to TNI and then gradual cooling. The insets are conoscopic images.

Fig. 5
Fig. 5

POM images of dendrimer/LC (1/99, wt/wt) mixtures on the organic polymer film cast on a glass plate. The scale indicates the surface free energy of the polymers. For abbreviation of the polymers, see Table 2.

Fig. 6
Fig. 6

POM images of (a) D-6PPCN/5CB and (b) D-6PC5/ZLI-4792 mixture (1/99, wt/wt) applied a horizontal AC electric field of 10 V at room temperature. The cell gaps are 3 μm. The dark circles are due to the spacer particle and the orientation defect around them.

Fig. 7
Fig. 7

Change in transmittance of the LC cell versus time when applying an AC voltage (10V) at 150 msec intervals. Periods of on-state of the AC voltage are indicated by the arrows. The cell was filled with the D-6PC5/ZLI-4792 (1/99, wt/wt) mixture, and the cell gap was 7μm.

Fig. 8
Fig. 8

Schematic representation of the dendrimer-induced vertical alignment. The filled and open bars indicate the mesogens in the denrimer and NLC, respectively. The lines represent the dendrimer core and the spacer chain.

Tables (2)

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Table 1 Solubility of the dendrimers in the nematic host LCs a)

Tables Icon

Table 2 The substrates and their surface free energy (γs)

Equations (1)

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γ l ( 1 + cos θ ) = 2 ( γ s d γ l d ) 1 / 2 + 2 ( γ s h γ l h ) 1 / 2

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