Kapton HPP-ST polyimide film PI (Kapton HPP-ST)
C22H10O5N2 repeat unit, poly(4,4'-oxydiphenylene-pyromellitimide), made from pyromellitic dianhydride and 4,4'-oxydianiline
Also known as Kapton® HPP-ST
Kapton HPP-ST is a surface-treated all-polyimide film sold by Qnity Electronics, a DuPont spinoff that makes Kapton.
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Recipe, share of the weight
- C not statedCarbon
- H not statedHydrogen
- O not statedOxygen
- N not statedNitrogen
Best for
Flexible printed circuit and PCB stencil films where adhesion treatment and a 231.0 MPa tensile strength at 23 °C matter, in the 100HPP-ST grade (25.4 µm)
Weakest at
Heat rating under load: the sources give a UL 746B relative thermal index of 240 °C (electrical) and 200 °C (mechanical), which are ratings and not service limits, and no HPP-ST value for in-orbit erosion was read
Risk at a glance
- People None found. Film low hazard; monomers GHS Danger
- If it fails Moderate. Atomic oxygen erosion in low Earth orbit
- Corrosion Moderate. NASA's erosion study ranks Kapton H as eroding more than fluoropolymers, and no HPP-ST erosion yield was recorded.
Quick facts: PI (Kapton HPP-ST)
| Property | Value | Basis |
|---|---|---|
| Density | 1.42 g/cm³ | 1 sourced value |
| Tensile strength | 165 to 231 MPa | 2 sourced values across conditions |
| Young's modulus | 2.8 GPa | 1 sourced value |
| Thermal conductivity | 0.12 W/(m·K) | 1 sourced value |
What is the density of Kapton HPP-ST polyimide film?
Kapton HPP-ST polyimide film has a density of 1.42 g/cm³. The source and test conditions are listed in the properties table on this page.
What is the thermal conductivity of Kapton HPP-ST polyimide film?
Kapton HPP-ST polyimide film has a thermal conductivity of 0.12 W/(m·K). The source and test conditions are listed in the properties table on this page.
What is the tensile strength of Kapton HPP-ST polyimide film?
Kapton HPP-ST polyimide film has a tensile strength of 165 to 231 MPa. The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the Young's modulus of Kapton HPP-ST polyimide film?
Kapton HPP-ST polyimide film has a Young's modulus of 2.8 GPa. The source and test conditions are listed in the properties table on this page.
What is Kapton HPP-ST polyimide film used for?
Uses recorded in the sources include Flexible printed circuit substrate and PCB stencil; Spacecraft solar array and thermal management film (Kapton family).
Why it exists
Kapton HPP-ST is an all-polyimide film from Qnity Electronics with a surface treatment for adhesion. The 100HPP-ST grade (25.4 µm, 1 mil) has a tensile strength of 231.0 MPa and an elongation at break of 72 % at 23 °C, as printed on the manufacturer product page. Its dielectric strength is 303 kV/mm, and the specification caps shrinkage at 0.10 % after 1 hour at 200 °C.
Where it's used
Use
Flexible printed circuit substrate and PCB stencil film, with screen printing and insulation tubing, as listed on the product page.
Use
Spacecraft solar array and thermal management film, in the Kapton family, as stated in the summary PDF.
Recipe
C22H10O5N2 repeat unit, poly(4,4'-oxydiphenylene-pyromellitimide), made from pyromellitic dianhydride and 4,4'-oxydianiline; the manufacturer calls HPP-ST an all-polyimide film with the properties of Type HN
Kapton HPP-ST is a polyimide film. Wikipedia says Kapton is produced by condensation of pyromellitic dianhydride (PMDA) and 4,4'-oxydianiline (ODA). The NASA report prints the repeat unit as C22H10O5N2 for Kapton H and HN, and the manufacturer describes HPP-ST as an all-polyimide film with the properties of Type HN.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Carbon C | not stated | 22 carbon atoms per repeat unit (C22H10O5N2, NASA report): the aromatic rings of the dianhydride and diamine units, plus the imide carbonyl carbons. |
| Hydrogen H | not stated | 10 hydrogen atoms per repeat unit (C22H10O5N2, NASA report), on the aromatic rings. |
| Oxygen O | not stated | 5 oxygen atoms per repeat unit (C22H10O5N2, NASA report): the carbonyl oxygens of the imide rings and the ether oxygen of the oxydiphenylene unit. |
| Nitrogen N | not stated | 2 nitrogen atoms per repeat unit (C22H10O5N2, NASA report): the imide nitrogens that join the dianhydride and diamine units. |
Weight shares are as printed in the sources.
What it can do
Carry a thin load
231.0 MPa tensile strength and 72 % elongation at break at 23 °C for 100HPP-ST (product page).
Hold its shape in heat
shrinkage at most 0.10 % after 1 hour at 200 °C (specification Table 5, 25.4 µm).
Insulate a thin film
303 kV/mm dielectric strength and a dielectric constant of 3.40 at 1 kHz for 100HPP-ST.
Burn slowly
limiting oxygen index of 37 % for 25 µm HPP-ST (ASTM D-2863, summary PDF).
How it compares
Every value here is for one manufacturer's HPP-ST film, read from its product page and summary PDF, so the figures are typical or specification values, not a ranking against other polyimide films. The 231.0 MPa tensile strength and 1.42 g/cc density are typical for 25 µm film, and the 165 MPa minimum is the specification floor for the same thickness. The 303 kV/mm dielectric strength is typical, against a 236 kV/mm minimum.
The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details. Other materials are shown beside it; each was measured under its own conditions, so open its page before comparing closely. Compare every grade in the family.
| Measurement | PI (Kapton HPP-ST) | PI (CP1) | PI (Kapton H) | PI (Kapton HN) | PI (PMR-15) | PI (Upilex-S) |
|---|---|---|---|---|---|---|
| Thermal behavior and safety | ||||||
| Thermal conductivity, Kapton 100HPP-ST | 0.12 W/mK10 | no data | no data | 0.12 W/(m K) | no data | 0.29 W/(m.K) |
| Shrinkage after 30 min at 150 °C, 25 µm HPP-ST film | 0.03 %12 | no data | no data | no data | no data | no data |
| Shrinkage maximum at 200 °C for 1 h, 25.4 µm HPP-ST film, MD and TD | 0.1 %13 | no data | no data | no data | no data | no data |
| UL electrical relative thermal index, Kapton HPP-ST | 240 °C14 | no data | no data | no data | no data | no data |
| UL mechanical relative thermal index, Kapton HPP-ST | 200 °C15 | no data | no data | no data | no data | no data |
| Physical and electrical | ||||||
| Density, Kapton HPP-ST 25 µm film | 1.42 g/cc5 | 1.419 g/cm³ | 1.427 g/cm³ | 1.42 g/cm³ | 1.287 g/cm³ | 1.387 g/cm³ |
| Other measurements | ||||||
| Tensile strength at 23 °C, Kapton 100HPP-ST | 231 MPa1 | 87 MPa | no data | no data | no data | 520 MPa |
| Tensile strength minimum, 25.4 µm (1.00 mil) film, MD and TD | 165 MPa2 | 87 MPa | no data | no data | no data | 520 MPa |
| Elongation at break at 23 °C, Kapton 100HPP-ST | 72 %3 | 16 percent | no data | no data | no data | 40 % |
| Tensile modulus at 23 °C, Kapton 100HPP-ST | 2.8 GPa4 | 2 GPa | no data | no data | no data | 9.1 GPa |
| Dielectric strength, Kapton 100HPP-ST | 303 kV/mm6 | no data | no data | 303 kV/mm | no data | 6.8 kV |
| Dielectric strength minimum, 25.4 µm (1.00 mil) film | 236 kV/mm7 | no data | no data | 303 kV/mm | no data | 6.8 kV |
| Dielectric constant at 1 kHz, Kapton 100HPP-ST | 3.4 -8 | 2.4 - | no data | 3.4 (dimensionless) | no data | 3.5 - |
| Dissipation factor at 1 kHz, 25 µm film | 0.0018 -9 | no data | no data | no data | no data | 0.0013 - |
| Limiting oxygen index, 25 µm HPP-ST film | 37 %11 | no data | no data | no data | no data | no data |
Why choose it, and why not
Good for
- Flexible circuit and stencil films where adhesion treatment and 231.0 MPa tensile strength at 23 °C matter.
- Thin insulation at high voltage: 303 kV/mm dielectric strength at 25.4 µm, from the product page.
Watch out for
- Heat rating under load: the relative thermal indices are 240 °C (electrical) and 200 °C (mechanical) under UL 746B. These are ratings, not service limits.
- Atomic oxygen: NASA ranks Kapton H as eroding more than fluoropolymers in low Earth orbit. No HPP-ST erosion yield was recorded.
- Thermal conductivity: the product page gives 0.12 W/mK for 100HPP-ST, and the summary PDF gives a different value for Type 100 HN.
Kapton HPP-ST is a 25.4 µm all-polyimide film with a tensile strength of 231.0 MPa, an elongation at break of 72 % and a dielectric strength of 303 kV/mm at 23 °C, per the manufacturer. Its heat ratings are UL 746B indices, and no HPP-ST data for in-orbit erosion or ageing were read.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Other names and standards
The same grade under other systems, as datasheets and standards print them. Each code was checked against the page it comes from.
| System | Codes |
|---|---|
| Trade name | Kapton® HPP-ST |
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Tensile strength at 23 °C, Kapton 100HPP-ST | Typical value printed on the manufacturer product page. The summary PDF prints the same 231 MPa for 25 µm HPP-ST by ASTM D-882. | grade Kapton HPP-ST, 100HPP-ST, 25.4 µm (1 mil) filmtemperature 23 °C | — |
| 2 | Tensile strength minimum, 25.4 µm (1.00 mil) film, MD and TD | Specification minimum (min.) for 25.4 µm film; the table footnote says it also applies to HPP-ST. ASTM D-882-91 Method A. | grade Kapton HN and HPP-ST, 1.00 mil (25.4 µm) filmtemperature 23 °Cdirection MD and TD, minimum | — |
| 3 | Elongation at break at 23 °C, Kapton 100HPP-ST | Typical value printed on the manufacturer product page. The summary PDF prints 72 % for 25 µm HPP-ST by ASTM D-882. | grade Kapton 100HPP-ST, 25.4 µm filmtemperature 23 °C | — |
| 4 | Tensile modulus at 23 °C, Kapton 100HPP-ST | Typical value printed on the manufacturer product page; no test standard is printed against this column in the text read | grade Kapton 100HPP-ST, 25.4 µm filmtemperature 23 °C | — |
| 5 | Density, Kapton HPP-ST 25 µm film | Typical value by ASTM D-1505, as printed in the summary PDF; the product page prints the same 1.42 g/cc for 100HPP-ST | grade Kapton HPP-ST, 25 µm (1 mil) film | — |
| 6 | Dielectric strength, Kapton 100HPP-ST | Typical value printed on the manufacturer product page. The summary PDF Table 7 prints 303 kV/mm for 25 µm HN and HPP-ST by ASTM D-149. | grade Kapton 100HPP-ST, 25.4 µm filmtest 60 Hz, 1/4 in electrodes, 500 V/sec rise | — |
| 7 | Dielectric strength minimum, 25.4 µm (1.00 mil) film | Specification minimum (min.) for 25.4 µm film; the table footnote says it also applies to HPP-ST | grade Kapton HN and HPP-ST, 1.00 mil (25.4 µm) filmtest ASTM D-149-97, AC, flat sheets between 1/4 in brass electrodes | — |
| 8 | Dielectric constant at 1 kHz, Kapton 100HPP-ST | Typical value printed on the manufacturer product page. The summary PDF Table 7 prints 3.4 at 1 kHz for 25 µm HN and HPP-ST by ASTM D-150. | grade Kapton 100HPP-ST, 25.4 µm filmfrequency 1 kHz | — |
| 9 | Dissipation factor at 1 kHz, 25 µm film | Typical value by ASTM D-150, as printed in the summary PDF | grade Kapton HN and HPP-ST, 25 µm (1 mil) filmfrequency 1 kHz | — |
| 10 | Thermal conductivity, Kapton 100HPP-ST | Typical value printed on the manufacturer product page. The page text read does not map a test standard to this column. A different value for Type 100 HN is in the summary PDF (see gaps). | grade Kapton 100HPP-ST, 25.4 µm film | — |
| 11 | Limiting oxygen index, 25 µm HPP-ST film | Typical value by ASTM D-2863, as printed in the summary PDF. Not a canonical name in property-canon, so the custom name limiting_oxygen_index is used. | grade Kapton HPP-ST, 25 µm (1 mil) film | — |
| 12 | Shrinkage after 30 min at 150 °C, 25 µm HPP-ST film | Typical value by IPC TM 650 Method 2.2.4A, as printed in the summary PDF | grade Kapton HPP-ST, 25 µm (1 mil) filmtemperature 150 °Ctime 30 min | — |
| 13 | Shrinkage maximum at 200 °C for 1 h, 25.4 µm HPP-ST film, MD and TD | Specification maximum (max.) for HPP-ST, as printed in the Table 5 shrinkage test method | grade Kapton HPP-ST, 1.00 mil (25.4 µm) filmtemperature 200 °Ctime 1 hrdirection MD and TD, maximum | — |
| 14 | UL electrical relative thermal index, Kapton HPP-ST | Rating printed on the manufacturer product page under Electrical, UL Electrical RTI. A rating, not a continuous service limit. | grade Kapton HPP-STstandard UL 746B, electrical | — |
| 15 | UL mechanical relative thermal index, Kapton HPP-ST | Rating printed on the manufacturer product page under Mechanical, UL Mechanical Strength RTI. A rating, not a continuous service limit. | grade Kapton HPP-STstandard UL 746B, mechanical strength | — |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Low Earth orbit, atomic oxygen | moderate | NASA's erosion study ranks Kapton H as eroding more than fluoropolymers, and no HPP-ST erosion yield was recorded.1 |
| Heat in air at 325 °C, Type HN film | not rated | The summary PDF plots strength and elongation retained after air ageing at 325 °C, for Type HN and not HPP-ST.2 |
| Solvents and 2 N hydrochloric acid, 10 min at 23 °C, Type HN film | low | Type HN keeps most of its tensile strength in common solvents, and hydrochloric acid gives the lowest retention in Table 10.3 |
| Hot water at 100 °C, Type HN film | not rated | Strength and elongation after exposure to 100 °C water are plotted for HN, and no HPP-ST water-exposure value was read.4 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Low Earth orbit, atomic oxygen | The NASA report says some polymers, such as the fluoropolymers, had low erosion yields compared with polyimide Kapton H. Kapton HPP-ST is a different grade, so its erosion yield is not recorded in this profile. | basis Kapton H, a different grade from HPP-ST, exposed in low Earth orbit on MISSE 2 per the NASA report |
| 2 | Heat in air at 325 °C, Type HN film | Figures 6 and 7 plot tensile strength and elongation retained for 25 µm Type HN film after ageing in air at 325 °C. The retention values sit on the curves and are not printed as numbers in the text, so no retention figure is recorded. | basis Type HN film, 25 µm (1 mil), not HPP-ST |
| 3 | Solvents and 2 N hydrochloric acid, 10 min at 23 °C, Type HN film | Table 10 prints tensile retained after isopropyl alcohol, toluene, methyl ethyl ketone, methylene chloride with trichloroethylene, and 2 N hydrochloric acid. The summary says HPP-ST chemical properties are similar to HN; this is a statement, not a test on HPP-ST. | basis Typical values for Type HN film, 25 µm (1 mil); HPP-ST described as similar |
| 4 | Hot water at 100 °C, Type HN film | Figures 3 and 4 plot tensile strength and ultimate elongation after exposure to 100 °C water for 25 µm Type HN film. | basis Type HN film, 25 µm (1 mil), not HPP-ST |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
The finished film has no GHS classification printed in the sources read, but its two monomers carry GHS Danger hazard statements.
- Film
- The summary PDF says Kapton is unlikely to add appreciably to fire hazards in storage or use. Bulk quantities over 100 lb should be kept away from flammable materials.
- Static
- Processing can generate a strong static charge, which can build to many thousands of volts and cause a flash fire in dust or solvent-laden air.
- Monomers
- Pyromellitic dianhydride carries Danger with H317, H318 and H334. 4,4'-oxydianiline carries Danger with H301, H311, H331, H340, H350, H361f and H411 (Wikipedia Chembox).
If it fails
The failure routes in these sources are atomic oxygen erosion in low Earth orbit and strength loss after heat ageing for HN.
- Atomic oxygen
- NASA ranks Kapton H as eroding more than fluoropolymers in low Earth orbit. No HPP-ST erosion yield was recorded, because the NASA values are printed in exponent form.
- Heat
- The summary PDF plots strength retained after air ageing at 325 °C for Type HN, not HPP-ST.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Atomic oxygen erosion in low Earth orbitmoderate severity | Polyimide film exposed to atomic oxygen in low Earth orbitNASA ranks Kapton H as eroding more than fluoropolymers, so bare film would need cover. No HPP-ST erosion yield was recorded. |
| Strength loss after heat ageing in airmoderate severity | Air ageing at 325 °C, Type HN dataStrength and elongation retention are plotted for HN and are not printed as HPP-ST values, so the HPP-ST margin is not recorded. |
| Dielectric breakdown of thin filmmoderate severity | AC voltage above the breakdown value on 25.4 µm filmThe minimum breakdown for 25.4 µm film is 236 kV/mm (ASTM D-149), so a design margin is needed above that value. |
Handling and storage
- The summary PDF says soldering rarely produces off-gases of toxicological significance, and that a heated element can remove insulation.
- Use adequate ventilation when handling Kapton at high temperatures, and remove the film from equipment before direct welding.
Supply and geography
How common the raw materials are and where they come from.
Kapton HPP-ST film (manufacturer)
Pyromellitic dianhydride (PMDA), dianhydride monomer
4,4'-Oxydianiline (ODA), diamine monomer
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
Show the full YAML
spore: profile
id: pi-kapton-hpp-st
spore_version: 0.2
family: polyimides
name: Kapton HPP-ST polyimide film
abbreviation: PI (Kapton HPP-ST)
role: surface-treated all-polyimide film for flexible circuits, PCB stencils and laminates
category: polymers
type: polyimides
summary: Kapton HPP-ST is a surface-treated all-polyimide film sold by Qnity Electronics, a DuPont spinoff that makes Kapton. For the 100HPP-ST grade (25.4 µm, 1 mil), the manufacturer prints a tensile strength of 231.0 MPa and an elongation at break of 72 % at 23 °C. The 25.4 µm film has a dielectric strength of 303 kV/mm and a dielectric constant of 3.40 at 1 kHz, and the specification caps shrinkage at 0.10 % after 1 hour at 200 °C.
best_for: Flexible printed circuit and PCB stencil films where adhesion treatment and a 231.0 MPa tensile strength at 23 °C matter, in the 100HPP-ST grade (25.4 µm)
weakest_at: 'Heat rating under load: the sources give a UL 746B relative thermal index of 240 °C (electrical) and 200 °C (mechanical), which are ratings and not service limits, and no HPP-ST value for in-orbit erosion was read'
identity:
formula: C22H10O5N2 repeat unit, poly(4,4'-oxydiphenylene-pyromellitimide), made from pyromellitic dianhydride and 4,4'-oxydianiline; the manufacturer calls HPP-ST an all-polyimide film with the properties of Type HN
source: nasa-tm-2008-215490
where: Table of polymer erosion data, row Polyimide (PMDA) PI (Kapton H), formula column C22H10O5N2; Wikipedia Kapton article gives the chemical name for Kapton K and HN
designations:
- system: Trade name
code: Kapton® HPP-ST
source: qnity-kapton-spec
where: Introduction page, heading Kapton® HPP-ST polyimide film
tags:
applications:
- electronics-and-chips
- solar-arrays
- thermal-control
properties:
- benchmark: ultimate_tensile_strength
label: Tensile strength at 23 °C, Kapton 100HPP-ST
value: 231
unit: MPa
scope: material
conditions:
grade: Kapton HPP-ST, 100HPP-ST, 25.4 µm (1 mil) film
temperature: 23 °C
method: Typical value printed on the manufacturer product page. The summary PDF prints the same 231 MPa for 25 µm HPP-ST by ASTM D-882.
status: ground
source: qnity-hpp-st-page
where: Kapton HPP-ST Product Properties table, row Kapton 100HPP-ST, Tensile Strength @23°C (MPa)
- benchmark: ultimate_tensile_strength
label: Tensile strength minimum, 25.4 µm (1.00 mil) film, MD and TD
value: 165
unit: MPa
scope: material
conditions:
grade: Kapton HN and HPP-ST, 1.00 mil (25.4 µm) film
temperature: 23 °C
direction: MD and TD, minimum
method: Specification minimum (min.) for 25.4 µm film; the table footnote says it also applies to HPP-ST. ASTM D-882-91 Method A.
status: ground
source: qnity-kapton-spec
where: Table 2, Mechanical Properties of Kapton HN polyimide film, row Tensile Strength psi (MPa) at 23°C min., column 1.00 (25.4)
- benchmark: elongation
label: Elongation at break at 23 °C, Kapton 100HPP-ST
value: 72
unit: '%'
scope: material
conditions:
grade: Kapton 100HPP-ST, 25.4 µm film
temperature: 23 °C
method: Typical value printed on the manufacturer product page. The summary PDF prints 72 % for 25 µm HPP-ST by ASTM D-882.
status: ground
source: qnity-hpp-st-page
where: Kapton HPP-ST Product Properties table, row Kapton 100HPP-ST, Elongation % to Break @23°C
- benchmark: elastic_modulus
label: Tensile modulus at 23 °C, Kapton 100HPP-ST
value: 2.8
unit: GPa
scope: material
conditions:
grade: Kapton 100HPP-ST, 25.4 µm film
temperature: 23 °C
method: Typical value printed on the manufacturer product page; no test standard is printed against this column in the text read
status: ground
source: qnity-hpp-st-page
where: Kapton HPP-ST Product Properties table, row Kapton 100HPP-ST, Tensile Modulus @23°C (GPa)
- benchmark: density
label: Density, Kapton HPP-ST 25 µm film
value: 1.42
unit: g/cc
scope: material
conditions:
grade: Kapton HPP-ST, 25 µm (1 mil) film
method: Typical value by ASTM D-1505, as printed in the summary PDF; the product page prints the same 1.42 g/cc for 100HPP-ST
status: ground
source: qnity-kapton-summary
where: Table 3, Physical and Thermal Properties of Kapton Type HPP-ST Film, row Density g/cc or g/mL, 25 µm column
- benchmark: dielectric_strength
label: Dielectric strength, Kapton 100HPP-ST
value: 303
unit: kV/mm
scope: material
conditions:
grade: Kapton 100HPP-ST, 25.4 µm film
test: 60 Hz, 1/4 in electrodes, 500 V/sec rise
method: Typical value printed on the manufacturer product page. The summary PDF Table 7 prints 303 kV/mm for 25 µm HN and HPP-ST by ASTM D-149.
status: ground
source: qnity-hpp-st-page
where: Kapton HPP-ST Product Properties table, row Kapton 100HPP-ST, Dielectric Strength (kV/mm)
- benchmark: dielectric_strength
label: Dielectric strength minimum, 25.4 µm (1.00 mil) film
value: 236
unit: kV/mm
scope: material
conditions:
grade: Kapton HN and HPP-ST, 1.00 mil (25.4 µm) film
test: ASTM D-149-97, AC, flat sheets between 1/4 in brass electrodes
method: Specification minimum (min.) for 25.4 µm film; the table footnote says it also applies to HPP-ST
status: ground
source: qnity-kapton-spec
where: Table 3, Electrical Properties of Kapton HN polyimide film, row Dielectric Strength AC V/mil (kV/mm) min., column 1.00 (25.4)
- benchmark: dielectric_constant
label: Dielectric constant at 1 kHz, Kapton 100HPP-ST
value: 3.4
unit: '-'
scope: material
conditions:
grade: Kapton 100HPP-ST, 25.4 µm film
frequency: 1 kHz
method: Typical value printed on the manufacturer product page. The summary PDF Table 7 prints 3.4 at 1 kHz for 25 µm HN and HPP-ST by ASTM D-150.
status: ground
source: qnity-hpp-st-page
where: Kapton HPP-ST Product Properties table, row Kapton 100HPP-ST, Dielectric Constant @ 1 kHz
- benchmark: dissipation_factor
label: Dissipation factor at 1 kHz, 25 µm film
value: 0.0018
unit: '-'
scope: material
conditions:
grade: Kapton HN and HPP-ST, 25 µm (1 mil) film
frequency: 1 kHz
method: Typical value by ASTM D-150, as printed in the summary PDF
status: ground
source: qnity-kapton-summary
where: Table 7, Typical Electrical Properties of Kapton Type HN and HPP-ST Films, Dissipation Factor, 25 µm (1 mil) row
- benchmark: thermal_conductivity
label: Thermal conductivity, Kapton 100HPP-ST
value: 0.12
unit: W/mK
scope: material
conditions:
grade: Kapton 100HPP-ST, 25.4 µm film
method: Typical value printed on the manufacturer product page. The page text read does not map a test standard to this column. A different value for Type 100 HN is in the summary PDF (see gaps).
status: ground
source: qnity-hpp-st-page
where: Kapton HPP-ST Product Properties table, row Kapton 100HPP-ST, Thermal Conductivity (W/mK)
- benchmark: limiting_oxygen_index
label: Limiting oxygen index, 25 µm HPP-ST film
value: 37
unit: '%'
scope: material
conditions:
grade: Kapton HPP-ST, 25 µm (1 mil) film
method: Typical value by ASTM D-2863, as printed in the summary PDF. Not a canonical name in property-canon, so the custom name limiting_oxygen_index is used.
status: ground
source: qnity-kapton-summary
where: Table 3, Physical and Thermal Properties of Kapton Type HPP-ST Film, Limiting Oxygen Index % row, 25 µm column
- benchmark: thermal_shrinkage
label: Shrinkage after 30 min at 150 °C, 25 µm HPP-ST film
value: 0.03
unit: '%'
scope: material
conditions:
grade: Kapton HPP-ST, 25 µm (1 mil) film
temperature: 150 °C
time: 30 min
method: Typical value by IPC TM 650 Method 2.2.4A, as printed in the summary PDF
status: ground
source: qnity-kapton-summary
where: Table 3, Physical and Thermal Properties of Kapton Type HPP-ST Film, Shrinkage % 30 min at 150°C row, 25 µm column
- benchmark: thermal_shrinkage
label: Shrinkage maximum at 200 °C for 1 h, 25.4 µm HPP-ST film, MD and TD
value: 0.1
unit: '%'
scope: material
conditions:
grade: Kapton HPP-ST, 1.00 mil (25.4 µm) film
temperature: 200 °C
time: 1 hr
direction: MD and TD, maximum
method: Specification maximum (max.) for HPP-ST, as printed in the Table 5 shrinkage test method
status: ground
source: qnity-kapton-spec
where: Table 5, Shrinkage of Kapton HPP-ST polyimide film, row Shrinkage %, MD and TD at 200°C (392°F) max., column 1.00 (25.4)
- benchmark: relative_thermal_index
label: UL electrical relative thermal index, Kapton HPP-ST
value: 240
unit: °C
scope: material
conditions:
grade: Kapton HPP-ST
standard: UL 746B, electrical
method: Rating printed on the manufacturer product page under Electrical, UL Electrical RTI. A rating, not a continuous service limit.
status: ground
source: qnity-hpp-st-page
where: Kapton HPP-ST Product Properties classification block, Electrical group, UL Electrical RTI (°C) row
- benchmark: relative_thermal_index
label: UL mechanical relative thermal index, Kapton HPP-ST
value: 200
unit: °C
scope: material
conditions:
grade: Kapton HPP-ST
standard: UL 746B, mechanical strength
method: Rating printed on the manufacturer product page under Mechanical, UL Mechanical Strength RTI. A rating, not a continuous service limit.
status: ground
source: qnity-hpp-st-page
where: Kapton HPP-ST Product Properties classification block, Mechanical group, UL Mechanical Strength RTI (°C) row
corrosion:
- environment: Low Earth orbit, atomic oxygen
headline: NASA's erosion study ranks Kapton H as eroding more than fluoropolymers, and no HPP-ST erosion yield was recorded.
effect: The NASA report says some polymers, such as the fluoropolymers, had low erosion yields compared with polyimide Kapton H. Kapton HPP-ST is a different grade, so its erosion yield is not recorded in this profile.
rating: moderate
conditions:
basis: Kapton H, a different grade from HPP-ST, exposed in low Earth orbit on MISSE 2 per the NASA report
source: nasa-tm-2008-215490
where: Introduction, paragraph beginning "As LEO erosion yield data gradually became available"
- environment: Heat in air at 325 °C, Type HN film
headline: The summary PDF plots strength and elongation retained after air ageing at 325 °C, for Type HN and not HPP-ST.
effect: Figures 6 and 7 plot tensile strength and elongation retained for 25 µm Type HN film after ageing in air at 325 °C. The retention values sit on the curves and are not printed as numbers in the text, so no retention figure is recorded.
rating: unknown
conditions:
basis: Type HN film, 25 µm (1 mil), not HPP-ST
source: qnity-kapton-summary
where: Figures 6 and 7, Thermal Aging section
- environment: Solvents and 2 N hydrochloric acid, 10 min at 23 °C, Type HN film
headline: Type HN keeps most of its tensile strength in common solvents, and hydrochloric acid gives the lowest retention in Table 10.
effect: Table 10 prints tensile retained after isopropyl alcohol, toluene, methyl ethyl ketone, methylene chloride with trichloroethylene, and 2 N hydrochloric acid. The summary says HPP-ST chemical properties are similar to HN; this is a statement, not a test on HPP-ST.
rating: low
conditions:
basis: Typical values for Type HN film, 25 µm (1 mil); HPP-ST described as similar
source: qnity-kapton-summary
where: Table 10, Chemical Properties of Kapton Type HN Film, 25 µm, and the paragraph before it
- environment: Hot water at 100 °C, Type HN film
headline: Strength and elongation after exposure to 100 °C water are plotted for HN, and no HPP-ST water-exposure value was read.
effect: Figures 3 and 4 plot tensile strength and ultimate elongation after exposure to 100 °C water for 25 µm Type HN film.
rating: unknown
conditions:
basis: Type HN film, 25 µm (1 mil), not HPP-ST
source: qnity-kapton-summary
where: Figures 3 and 4, mechanical properties section
risks:
hazards:
- text: The summary PDF says Kapton is unlikely to add appreciably to fire hazards in storage or use. Bulk quantities over 100 lb should be stored away from flammable materials, and firefighters should use a fresh air supply or respirator.
ghs: []
source: qnity-kapton-summary
where: Safety and Handling, Fire Hazards
- text: The summary PDF says processing can generate a strong static charge, which can build to many thousands of volts. In dust- or solvent-laden air, a flash fire or explosion could result.
ghs: []
source: qnity-kapton-summary
where: Safety and Handling, Static Electricity
- text: The monomer pyromellitic dianhydride carries GHS signal word Danger, with hazard statements H317, H318 and H334.
ghs:
- H317
- H318
- H334
source: wikipedia-pmda
where: Chembox, Hazards section
- text: The monomer 4,4'-oxydianiline carries GHS signal word Danger, with hazard statements H301, H311, H331, H340, H350, H361f and H411.
ghs:
- H301
- H311
- H331
- H340
- H350
- H361f
- H411
source: wikipedia-oda
where: Chembox, Hazards section
failure_risks:
- mode: Atomic oxygen erosion in low Earth orbit
trigger: Polyimide film exposed to atomic oxygen in low Earth orbit
consequence: NASA ranks Kapton H as eroding more than fluoropolymers, so bare film would need cover. No HPP-ST erosion yield was recorded.
severity: moderate
source: nasa-tm-2008-215490
where: Introduction, erosion comparison paragraph
- mode: Strength loss after heat ageing in air
trigger: Air ageing at 325 °C, Type HN data
consequence: Strength and elongation retention are plotted for HN and are not printed as HPP-ST values, so the HPP-ST margin is not recorded.
severity: moderate
source: qnity-kapton-summary
where: Figures 6 and 7, Thermal Aging section
- mode: Dielectric breakdown of thin film
trigger: AC voltage above the breakdown value on 25.4 µm film
consequence: The minimum breakdown for 25.4 µm film is 236 kV/mm (ASTM D-149), so a design margin is needed above that value.
severity: moderate
source: qnity-kapton-spec
where: Table 3, Electrical Properties of Kapton HN polyimide film, column 1.00 (25.4)
side_effects: []
handling:
- text: The summary PDF says soldering rarely produces off-gases of toxicological significance, and that a heated element can remove insulation.
source: qnity-kapton-summary
- text: Use adequate ventilation when handling Kapton at high temperatures, and remove the film from equipment before direct welding.
source: qnity-kapton-summary
mitigations: []
uses:
- application: electronics-and-chips
device: Flexible printed circuit substrate and PCB stencil
example: The product page lists electronic parts, printed circuit board stencils, screen printing and insulation tubing as applications for Kapton HPP-ST.
source: qnity-hpp-st-page
where: Kapton HPP-ST product page, Applications list
- application: solar-arrays
device: Spacecraft solar array and thermal management film (Kapton family)
example: The summary PDF says Kapton is used in applications such as the solar array and for thermal management in the United States space program. This describes the Kapton family, not HPP-ST alone.
source: qnity-kapton-summary
where: Opening paragraph of the Summary of Properties, page 1
supply:
- subject: Kapton HPP-ST film (manufacturer)
demand: Qnity Electronics is the named manufacturer. Wikipedia says Kapton has been manufactured by Qnity Electronics since November 2025, as a spinoff of DuPont. No market share, tonnage or country split for Kapton film was found in any source read.
routes: Kapton is made from a polyamic acid precursor that is cured to polyimide film. The manufacturer calls HPP-ST an all-polyimide film with a surface treatment on both sides for adhesion.
producers: []
critical_lists: []
substitutes: []
source: wikipedia-kapton
where: History (manufacturer as of November 2025); 3D printing section (polyamic acid precursor); summary PDF, Types of Kapton
- subject: Pyromellitic dianhydride (PMDA), dianhydride monomer
demand: Wikipedia says PMDA is the dianhydride used to prepare polyimide polymers such as Kapton. No producer or tonnage was found in the page read.
routes: Wikipedia says PMDA is prepared by gas-phase oxidation of 1,2,4,5-tetramethylbenzene, or related tetrasubstituted benzene derivatives.
producers: []
critical_lists: []
substitutes: []
source: wikipedia-pmda
where: Preparation section; Chembox
- subject: 4,4'-Oxydianiline (ODA), diamine monomer
demand: Wikipedia says the primary use of ODA is in polyimide and poly(ester)imide resins, and that it is the diamine condensed with PMDA to make Kapton. No producer or tonnage was found in the page read.
routes: The route to ODA is not described in the page read.
producers: []
critical_lists: []
substitutes: []
source: wikipedia-oda
where: Uses section
documents:
- title: Qnity Electronics product page, Kapton HPP-ST polyimide film (Product Properties table)
type: datasheet
url: https://www.qnityelectronics.com/products/kapton-hpp-st-polyimide-film
year: 2026
- title: Qnity Electronics, Kapton Summary of Properties (PDF)
type: datasheet
url: https://ekce-p-001.sitecorecontenthub.cloud/api/public/content/810b258c62404e42855984f345fdf8d7?v=a2916962
- title: Qnity Electronics, Kapton polyimide film specifications and tolerances (PDF)
type: datasheet
url: https://ekce-p-001.sitecorecontenthub.cloud/api/public/content/599767bd7af84d92827184ea3728c2b3?v=5670ee5b
- title: Banks, de Groh and Backus, Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit, NASA/TM-2008-215490
type: report
url: https://ntrs.nasa.gov/citations/20090011780
year: 2008
gaps:
- No HPP-ST value was read for coefficient of thermal expansion, glass transition, specific heat or melting point. The summary PDF prints these for Type 100 HN only, and it gives the melting point as None (ASTM E-794).
- Atomic oxygen erosion yields for Kapton H and HN in NASA/TM-2008-215490 are printed in exponent form, so they are not recorded here. No HPP-ST erosion yield was read.
- Radiation, UV and outgassing data for HPP-ST were not read as HPP-ST values. The summary's radiation and chemical tables are for Type HN, and the summary says HPP-ST chemical properties are similar to HN.
- 'Thermal conductivity conflicts across grades: the product page gives 0.12 W/mK for 100HPP-ST, and the summary PDF gives 0.20 W/m K for Type 100 HN. The HN value is a different grade, so only the HPP-ST value is recorded.'
- The product page does not map a test standard to each column in the text read, so the method on those rows says so. Where the summary PDF prints the same value by a named standard, that is cited in the method.
- Limiting oxygen index and relative thermal index are not canonical names in property-canon.yaml, so custom names are used.
- Producer shares, country splits and tonnage for Kapton film were not found in any source read. Qnity Electronics is named as the manufacturer, and the monomers have no producer figures.
- No Qnity safety data sheet for HPP-ST was read. Hazard entries come from the summary PDF safety section and from the Wikipedia Chembox data for the two monomers.
- Moisture absorption is printed as two values for HN and HPP-ST in the summary PDF with no clear row label in the text read, so it is not recorded.
- Tear strength (Elmendorf and Graves) and folding endurance for 25 µm HPP-ST are printed in the summary PDF Table 3 but have no canonical property name, so they are not recorded.
sources:
qnity-hpp-st-page:
title: Kapton HPP-ST polyimide film, Qnity Electronics product page
id: Product Properties table (row Kapton 100HPP-ST), Classification block, Applications list
url: https://www.qnityelectronics.com/products/kapton-hpp-st-polyimide-film
year: 2026
kind: datasheet
license: manufacturer web page, linked not reproduced
qnity-kapton-summary:
title: Kapton Summary of Properties, Qnity Electronics (PDF)
id: Table 3 (HPP-ST), Table 7 (electrical, HN and HPP-ST), Table 10 (chemical, HN), Safety and Handling
url: https://ekce-p-001.sitecorecontenthub.cloud/api/public/content/810b258c62404e42855984f345fdf8d7?v=a2916962
kind: datasheet
license: manufacturer PDF, linked not reproduced
qnity-kapton-spec:
title: Kapton polyimide film specifications and tolerances, Qnity Electronics (PDF)
id: Table 2 (mechanical, HN, footnote applies to HPP-ST), Table 3 (electrical, HN), Table 5 (HPP-ST shrinkage)
url: https://ekce-p-001.sitecorecontenthub.cloud/api/public/content/599767bd7af84d92827184ea3728c2b3?v=5670ee5b
kind: datasheet
license: manufacturer PDF, linked not reproduced
nasa-tm-2008-215490:
title: Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit
id: NASA/TM-2008-215490 (Banks, de Groh and Backus, 2008), NTRS 20090011780
url: https://ntrs.nasa.gov/citations/20090011780
year: 2008
kind: report
license: NASA public document
wikipedia-kapton:
title: Kapton, Wikipedia
id: Kapton article, History, Chemistry and variants, Usage (Spacecraft), 3D printing
url: https://en.wikipedia.org/wiki/Kapton
kind: web
license: CC BY-SA 4.0, linked not reproduced
wikipedia-polyimide:
title: Polyimide, Wikipedia
id: Polyimide article, lead section (Kapton condensation of PMDA and ODA)
url: https://en.wikipedia.org/wiki/Polyimide
kind: web
license: CC BY-SA 4.0, linked not reproduced
wikipedia-pmda:
title: Pyromellitic dianhydride, Wikipedia
id: Chembox (identifiers, properties, GHS hazards), Preparation section
url: https://en.wikipedia.org/wiki/Pyromellitic_dianhydride
kind: web
license: CC BY-SA 4.0, linked not reproduced
wikipedia-oda:
title: 4,4'-Oxydianiline, Wikipedia
id: Chembox (identifiers, properties, GHS hazards), Uses section
url: https://en.wikipedia.org/wiki/4,4%27-Oxydianiline
kind: web
license: CC BY-SA 4.0, linked not reproduced
license: CC-BY-4.0
updated: '2026-11-01'
review:
status: draft
method: assistant
checked_values: 15
unreachable: 0
caveats: 3
note: Values were read by an AI assistant on 2026-11-01 from the pages named in each entry. Product-page values are typical values with no test standard mapped to each column in the text read. Minimum and maximum values come from the specification PDF and apply to HN and HPP-ST by its footnote. The thermal conductivity value is for 100HPP-ST only.
story:
recipe:
line: Kapton HPP-ST is a polyimide film. Wikipedia says Kapton is produced by condensation of pyromellitic dianhydride (PMDA) and 4,4'-oxydianiline (ODA). The NASA report prints the repeat unit as C22H10O5N2 for Kapton H and HN, and the manufacturer describes HPP-ST as an all-polyimide film with the properties of Type HN.
parts:
- name: Carbon
symbol: C
role: '22 carbon atoms per repeat unit (C22H10O5N2, NASA report): the aromatic rings of the dianhydride and diamine units, plus the imide carbonyl carbons.'
- name: Hydrogen
symbol: H
role: 10 hydrogen atoms per repeat unit (C22H10O5N2, NASA report), on the aromatic rings.
- name: Oxygen
symbol: O
role: '5 oxygen atoms per repeat unit (C22H10O5N2, NASA report): the carbonyl oxygens of the imide rings and the ether oxygen of the oxydiphenylene unit.'
- name: Nitrogen
symbol: 'N'
role: '2 nitrogen atoms per repeat unit (C22H10O5N2, NASA report): the imide nitrogens that join the dianhydride and diamine units.'
risk_groups:
- title: For people
lead: The finished film has no GHS classification printed in the sources read, but its two monomers carry GHS Danger hazard statements.
level: 0
verdict: Film low hazard; monomers GHS Danger
points:
- label: Film
line: The summary PDF says Kapton is unlikely to add appreciably to fire hazards in storage or use. Bulk quantities over 100 lb should be kept away from flammable materials.
- label: Static
line: Processing can generate a strong static charge, which can build to many thousands of volts and cause a flash fire in dust or solvent-laden air.
- label: Monomers
line: Pyromellitic dianhydride carries Danger with H317, H318 and H334. 4,4'-oxydianiline carries Danger with H301, H311, H331, H340, H350, H361f and H411 (Wikipedia Chembox).
- title: If it fails
lead: The failure routes in these sources are atomic oxygen erosion in low Earth orbit and strength loss after heat ageing for HN.
level: 1
verdict: Erosion in orbit; heat ageing shown for HN
points:
- label: Atomic oxygen
line: NASA ranks Kapton H as eroding more than fluoropolymers in low Earth orbit. No HPP-ST erosion yield was recorded, because the NASA values are printed in exponent form.
- label: Heat
line: The summary PDF plots strength retained after air ageing at 325 °C for Type HN, not HPP-ST.
why: Kapton HPP-ST is an all-polyimide film from Qnity Electronics with a surface treatment for adhesion. The 100HPP-ST grade (25.4 µm, 1 mil) has a tensile strength of 231.0 MPa and an elongation at break of 72 % at 23 °C, as printed on the manufacturer product page. Its dielectric strength is 303 kV/mm, and the specification caps shrinkage at 0.10 % after 1 hour at 200 °C.
uses:
- where: Use
line: Flexible printed circuit substrate and PCB stencil film, with screen printing and insulation tubing, as listed on the product page.
- where: Use
line: Spacecraft solar array and thermal management film, in the Kapton family, as stated in the summary PDF.
can_do:
- label: Carry a thin load
line: 231.0 MPa tensile strength and 72 % elongation at break at 23 °C for 100HPP-ST (product page).
- label: Hold its shape in heat
line: shrinkage at most 0.10 % after 1 hour at 200 °C (specification Table 5, 25.4 µm).
- label: Insulate a thin film
line: 303 kV/mm dielectric strength and a dielectric constant of 3.40 at 1 kHz for 100HPP-ST.
- label: Burn slowly
line: limiting oxygen index of 37 % for 25 µm HPP-ST (ASTM D-2863, summary PDF).
compare: Every value here is for one manufacturer's HPP-ST film, read from its product page and summary PDF, so the figures are typical or specification values, not a ranking against other polyimide films. The 231.0 MPa tensile strength and 1.42 g/cc density are typical for 25 µm film, and the 165 MPa minimum is the specification floor for the same thickness. The 303 kV/mm dielectric strength is typical, against a 236 kV/mm minimum.
compare_rows:
- label: Density
benchmark: density
- label: Tensile strength
benchmark: ultimate_tensile_strength
- label: Dielectric strength
benchmark: dielectric_strength
handling:
- Name the grade, since HPP-ST and HN share some values but the surface treatment and shrinkage limits differ.
- Check the current supplier data sheet, since the product page and summary PDF give typical values with no test standard for each column.
- Keep film in a ventilated area when heating or welding, and remove it from equipment before direct welding.
good_for:
- Flexible circuit and stencil films where adhesion treatment and 231.0 MPa tensile strength at 23 °C matter.
- 'Thin insulation at high voltage: 303 kV/mm dielectric strength at 25.4 µm, from the product page.'
watch_out:
- 'Heat rating under load: the relative thermal indices are 240 °C (electrical) and 200 °C (mechanical) under UL 746B. These are ratings, not service limits.'
- 'Atomic oxygen: NASA ranks Kapton H as eroding more than fluoropolymers in low Earth orbit. No HPP-ST erosion yield was recorded.'
- 'Thermal conductivity: the product page gives 0.12 W/mK for 100HPP-ST, and the summary PDF gives a different value for Type 100 HN.'
verdict: Kapton HPP-ST is a 25.4 µm all-polyimide film with a tensile strength of 231.0 MPa, an elongation at break of 72 % and a dielectric strength of 303 kV/mm at 23 °C, per the manufacturer. Its heat ratings are UL 746B indices, and no HPP-ST data for in-orbit erosion or ageing were read.
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
| # | Source | Type | Year | Used for |
|---|---|---|---|---|
| Kapton HPP-ST polyimide film, Qnity Electronics product page | datasheet | 2026 | 9 values | |
| Kapton Summary of Properties, Qnity Electronics (PDF) | datasheet | 13 values | ||
| Kapton polyimide film specifications and tolerances, Qnity Electronics (PDF) | datasheet | 4 values | ||
| Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit | report | 2008 | 3 values | |
| Kapton, Wikipedia | web | 1 value | ||
| Polyimide, Wikipedia | web | 0 values | ||
| Pyromellitic dianhydride, Wikipedia | web | 2 values | ||
| 4,4'-Oxydianiline, Wikipedia | web | 2 values |
Updated