Covering, coating materials

UPIA®

"UPIA®" is a complete Polyimide varnish product line based on UBE's "U-varnish" brand, with new performance varnish grades developed from UBE's extensive experience and Superior technology.

Characteristics of "UPIA®"

(1) Composition of UBE Polyimide

Original composition polyimide

"UPIA®" is a polyimide precursor formed from UBE's proprietary "BPDA(Biphenyl tetracarboxylic dianhydride)" monomers. This is the original UBE varnish.

UBE polyimide film "UPILEX®" is produced using this unique UBE polyimide precursor giving it various and unique advantages. Polyimide coated film derived from the varnish of the same graded has the same properties.

Features of UBE Polyimide film UPILEX

Details of [UPILEX®] is Here.

(2) General properties of "UPIA®"

Property Category Heat-resistant
/High heat-resistant
(Existing grade)
NMP Free For secondary
battery binder
Measurement
condition
Unit UPIA-AT/ST
(U-Varnish-A/S)
UPIA-NF UPIA-LB
Solvent - *NMP Water *NMP, Water  
Solid content wt% 17-19 10-15 10-30 350°C, 30min
Density ×103kg/m3 1.10-1.11 1.05-1.10 1.05-1.15 25°C
Solution
viscosity
Pa·s 5-100 1-10 0.1-10 E-type, 30°C

(3) Temperature dependence of solution viscosity

Temperature dependence of solution viscosity

(4) Concentration dependence of solution viscosity

Easy viscosity adjustment

"UPIA®" can be used at any desired concentration by diluting it with anhydrous NMP or DMAc (N, N-dimethylacetamide).


(5) Storage stability

Storage stability

"UPIA®" has superior storage stability compared to conventional polyimide varnishes. It exhibits a very low increase in viscosity at room temperature, while conventional polyimide varnish must be refrigerated or frozen.

Other handling precautions are Here

.

Base grade

Heat-resistant varnish UPIA-AT (U-Varnish-A) / High heat-resistant varnish UPIA-ST (U-Varnish-S)

UPIA-AT, UPIA-ST is the same as the U-Varnish-A, U-Varnish-S.
UPIA-AT, UPIA-ST has received high praises of usability and high performance.

(1) Thermal properties

Non-melting/High heat resistance

Polyimide film obtained from "UPIA®" exhibits a high thermal decomposition temperature. Especially, "UPIA®-ST(U-Varnish-S)" has a thermal decomposition temperature above 550°C, so it does not soften, fluidize, or decompose under use temperatures and it is able to be used in high-temperature processes.
In addition, the polyimide coating has excellent dimensional stability even at high temperatures.

Property Unit UPIA-AT
(U-Varnish-A)
UPIA-ST
(U-Varnish-S)
Measurement
condition
Measurement Method
1001 1001 1002
Thickness μm 20 50 20 50 20 50
Solvent - NMP NMP NMP  
Solid content wt% 18.0±1.0 18.0±1.0 18.0±1.0 350°C, 30min
Solution viscosity Pa·s 5±1 5±1 100±10 E-type, 30°C
Heat treatment
highest temp.
°C 350 450 450  
Film properties Glass-transition
temp.Tg
°C 274 278 322 324 327 327 Dynamic viscoelasticity
5% weight
reduction temp.
°C 592 599 619 620 609 615 TGA
Thermal linear
expansion
coefficient
(50-200°C)
ppm/K 33 29 3 8 3 6 Fine linear dilatometer
Heat weight loss curve

(2) Mechanical properties

Resists abrasion/High tensile strength

Polyimide coating derived from "UPIA®" demonstrates excellent mechanical properties, especially high tensile strength and abrasion resistance.


Property Unit UPIA-AT (U-Varnish-A) UPIA-ST
(U-Varnish-S)
Measurement Method
1001 1001 1002
Thickness μm 20 50 20 50 20 50
Film properties      Tensile strength MPa 229 238 526 482 540 465 ASTM D882
Elongation % 92 99 35 40 35 37 ASTM D882
Tensile modulus GPa 3.7 3.7 9.8 9.3 10.1 9.6 ASTM D882

(3) Electric properties

High insulation properties

Polyimide coat obtained from "UPIA®" delivers a high electrical reliability, such as insulation.


Property Unit UPIA-AT
(U-Varnish-A)
UPIA-ST
(U-Varnish-S)
Measurement
condition
Measurement Method
1001 1001 1002
Thickness μm 20 50 20 50 20 50
Dielectric strength kV 7.7 10.3 7 10.2 6.7 9 ASTM D149
Volume resistivity Ω·m >1014 >1014 >1014 >1014 >1014 >1014 ASTM D257
Surface resistivity Ω >1016 >1016 >1016 >1016 >1016 >1016 ASTM D257

(4) Chemical-Resistant Properties

High chemical resistance

"UPIA®" has excellent resistance to common organic solvents and metallic salt solutions, and it also demonstrates better resistance to acids and alkalis than conventional products. In addition, it delivers superior performance when it comes to abrasion resistance and non- flammability.


Chemical resistance data of UPIA-AT1001(U-Varnish-A)

Chemical Characteristic value (Thickness: 20μm)
Strength
retention (%)
Elongation
retention (%)
Methylene chloride 95 96
Chloroform 88 90
Trichloroethylene 93 102
Methyl ethyl ketone 92 89
Ethanol 89 100
Xylene 99 84
m-Cresol 90 90
N-methyl-2-pyroridon 98 107
Glacial acetic acid 91 108
10% hydrochloric acid 91 82
10% sulfuric acid 93 94
2% sodium hydroxide 99 91
10% sodium hydroxide 82 81

Specialty grade (Details)

We will continue to develop special varnish grades delivering unique advantages for specific applications, based on properties of high heat resistance and chemical resistance.

(1) NMP free Varnish UPIA-NF

NMP free varnish UPIA-NF

We have developed UPIA-NF, using water as the solvent, eliminating the high polarity and high boiling point (NMP, etc.) organic solvent systems which are commonly used in conventional polyimide-based varnish.

In addition to reducing environmental and health problems, the disposal cost associated with organic solvents is significantly decreased.

  • Processing and properties of the water soluble varnish are equivalent to the NMP-based varnish.
  • Homogeneous polyimide coating is obtained compared to competitors water-dispersible type varnishes.
  • We can also provide solvent based, non-NMP varnish systems.
Property Unit UPIA-AT
(U-Varnish-A)
UPIA-ST
(U-Varnish-S)
UPIA-NF Measurement
condition
Measurement Method
1001
Heat-resistant
1001
High
heat-resistant
1001
Heat-resistant
2001
High
heat-resistant
Thickness μm 20 20 20 20 20 20 20 20
Heat treatment
highest temp.
°C 200 350 200 450 200 350 200 450  
Solvent - NMP NMP Water Water  
Solid content wt% 18.0±1.0 18.0±1.0 9.0±1.0 10.0±1.0 350°C, 30min
Solution viscosity Pa·s 5±1 5±1 5±1 1±0.5 E-type, 30°C
Japan's
Fire Defense Law
classification
- Type 3 Petroleum Substance, Type 4 Hazardous Material Type 3 Petroleum Substance, Type 4 Hazardous Material Non-hazardous materials Non-hazardous materials  
Film properties     Glass-transition
temp.Tg
°C 243 274 267 322 240 254 297 331 Dynamic viscoelasticity
Tensile strength MPa 175 229 235 526 195 196 204 450 ASTM D882
Elongation % 70 92 23 35 64 59 12 50 ASTM D882
Tensile modulus GPa 3.2 3.7 7.5 9.8 3.9 4.2 7 7.9 ASTM D882
5% weight
reduction temp.
°C 546 592 514 619 559 566 545 604 TGA
Breakdown
voltage
Dielectric
strength
kV 7.2 7.7 6.5 7 3.4 5.4 4.5 6 ASTM D149
Volume
resistivity
Ω·m >1014 >1014 >1014 >1014 >1014 >1014 >1014 >1014 ASTM D257
Surface
resistivity
Ω >1016 >1016 >1016 >1016 >1016 >1016 >1016 >1016 ASTM D257

(2) For secondary battery binder UPIA-LB

For secondary battery binder UPIA-LB

We have optimized UPIA-LB for lithium-ion battery binder applications.

  • For battery binder applications, we strengthened and optimized the required characteristics according to our customers needs.
  • UPIA-LB has the necessary toughness to overcome significant expansion of the electrode material.
  • This varnish has high adhesion to Copper, aluminum and SUS, so you should improve the adhesion to the current collector compared to other binder types.
  • This polyimide binder is highly resistant to the chemical exposure, it maintains performance, such as cracking resistance and adhesive strength, even immersed in the electrolyte solution
  • It has excellent long-term heat resistance, so it is able to be used in high-temperature applications.
  • UPIA-LB has excellent physical properties, even with relatively low temperature processing.
Property Unit UPIA-AT
(U-Varnish-A)
UPIA-LB Measurement
condition
Measurement
Method
1001 1001 2001
Thickness μm 20 20 20 20 20 20
Heat treatment
highest temp.
°C 200 350 200 350 150 200    
Solvent - NMP NMP Water    
Solid content wt% 18.0±1.0 30.0±1.0 18.0±1.0 350°C, 30min  
Solution viscosity Pa·s 5±1 5±1 0.5±0.2 E-type, 30°C  
Film properties     Cu adhesion - 5B 5B 5B 5B 5B 5B   ASTM D3359
Al adhesion - 5B 5B 5B 5B 5B 5B   ASTM D3359
SUS adhesion - 5B 5B 5B 5B 5B 5B   ASTM D3359
Tensile strength MPa 175 229 199 278 127 132   ASTM D882
Elongation % 70 92 88 107 53 45   ASTM D882
Tensile modulus GPa 3.2 3.7 3.2 4 2.8 3.2   ASTM D882
Break energy MJ/m3 86 150 118 191 70 75   ASTM D882
Electrolytic liquid resistance     Weight
change rate
% 1.2 0.2 0.1 ±0 ±0 ±0 25°C×24h
Electrolytic
liquid dipping
 
Thickness
change rate
% 0.5 ±0 0.1 ±0 ±0 ±0 25°C×24h
Electrolytic
liquid dipping
 
Tensile strength
retention
% 97 100 103 102 98 100 25°C×24h
Electrolytic
liquid dipping
ASTM D882
Elongation
retention
% 100 99 103 103 104 100 25°C×24h
Electrolytic
liquid dipping
ASTM D882
Break energy
retention
% 100 100 102 104 101 100 25°C×24h
Electrolytic
liquid dipping
ASTM D882