Specialty Glass : Products & Services

NA-35/NA-32R: LCD Display -
Alumino Silicate Glass


NA-35

HOYA's NA-35 is an alumino silicate glass with excellent thermal characteristics. It displays minimal surface cloudiness from contact with fluoric acid and is ideal for device substrates requiring high deposition temperature or fine patterning, such as poly-Si TFT and EL.

Low Shrinkage

NA-35 exhibits lower thermal shrinkage in high temperature heat treatment, even when compared to borosilicate glass. The NA-35's softening point is at 650°C, so its stability in shape and measurement during extremely high heat treatment (~600°C) makes it ideal for substrates of devices that require high process temperatures and patterning accuracy. It also has superb heat resistant characteristics, due to its low CTE at ~37 x 10-7/°C.

Minimal Cloudiness

The NA-35 is almost impervious to fluoric acid solution and exhibits minimal cloudiness when washing process using HF, NH4F, HF-HNO3, or HF-NH4F.

Consistency

Our facility is designed to handle and monitor all aspects of glass making. We melt and form, anneal, cut and chamfer, polish and inspect, all in-house. Due to this streamlined manufacturing process, we are able to maintain a very low level of defects.

Features

  • Low Shrinkage
  • Minimal Cloudiness
  • High Stability
  • Diverse Functionality
  • Non-Contact Drawn Formation
  • Non-Contact Annealing
  • No Surface Defects
  • No SiO2 Coating Needed
  • Standard Thickness 0.70mm

Applications

  • Flat Panel Displays
  • Diode Liquid Crystal Displays
  • Masks
  • Sensors
Glass Properties
Mechanical NA35 NA32R
Specific Gravity (g/cm)3 2.49 2.41
Young Modulus (Gpa) 68.3 70.9
Modulus of Rigidity 28.3 28.7
Modulus of Volume Elasticity 45.2 44.8
Knoop Hardness 4.9 5.2
Poissonís Ratio 0.24 0.23
Roughness (RMS, nm) 1um x 1um size 0.324 0.26
Thermal NA35 NA32R
CTE (x 10-7/°C) 38 33.8
Strain Point (°C) 645 654
Shrinkage (ppm at 400°C, 1 hr hold) 8.42 6.98
Shrinkage (ppm at 450°C, 1 hr hold) 17.86 13.59
Transformation Temp, Tg (°C) 702 717
Sag Temp, Ts (°C) 768 770
Optical NA35 NA32R
Refractive Index (Nd) 1.513 1.5089
Abbe Number (Vd) 62.2 62.5
Transmittance (nm, at 5%/80%) 235/323 236/326
Electrical NA35 NA32R
Volume Resistivity (Log-Ohm, at 350°C) 11.03 10.92
Dielectric Constant (S/m) 4.7 4.44
Chemical Durability NA35 NA32R
(weight loss/unit area, mg/cm )2    
HCl (5%/24hr/95°C) 1.55 1.6
HSO4 (1M/24hr/95°C) 1.18 1.24
HNO3 (1M/24hr/95°C) 0.7 0.78
HF (10%/20min/22°C) 4.36 3.48
NaOH (5%/6hr/95°C) 1.26 1.13
KOH (5%/6hr/95°C) 0.7 0.63

Note: The listed data are standard value. Because of continuous product improvement, the various data listed are subject to change without notice.