Choosing a remover from the resin family alone can damage the film or the parts under it when that family is not the product and cure state on the board. Match the named coating, the cure state, the removal file and the repair material before a local patch.
This page compares one HumiSeal UV removal sheet with Chemtronics’ resin-family notes. It is a document match for a maintenance lead, not a procedure for an energized board or a board whose coating record is missing.
Match the named coating product and its cure state to the removal file before anyone patches the board. In HumiSeal’s UV removal sheet, file date 10 August 2017 and read here on 14 October 2026, six products are listed, and the stripper cells differ between UV-only cure and full UV-plus-moisture cure. Chemtronics’ general guide, retrieved 11 October 2026, sorts removal by resin family and names a small-area remover pen. A family note or a pen does not fill a blank product cell. If the product name or the cure state is not in a document you hold, leave the removal and repair cells blank and stop.
- Write the product name exactly as the coating record prints it.
- Mark the cure state the file uses: UV exposure before moisture cure, or full UV-plus-moisture cure.
- Read the stripper cell for that pair. The printed word “softened” is not the printed word “yes”.
- Use a repair coating only when that same file names it.
- Stop when the product or the cure state is missing. Do not treat this page as work on an energized board.
The check belongs on the industrial applications route. When the board is inside installed equipment and its identity or permission is not already on an authorized record, use the non-invasive control-board service record and leave the coating cells blank.
| Input or item | What to record | Why it matters |
|---|---|---|
| Product name | Exact name from the coating record | A resin family does not select a stripper cell |
| Cure state | UV-only, or full UV plus moisture, as the file defines those states | The same product prints different cells in the two HumiSeal tables |
| Removal file | The document that names that product and that state | Temperatures and pressures stay inside the file that printed them |
| Repair coating | The coating that same file names, or blank | A general remover pen is not a listed repair coating |
| Geographic note | The footnote printed on a “yes” cell | Stripper 1100 is marked not available in the EU |
Does a resin family decide the remover and the repair coating?
No. A resin family is a Chemtronics sorting label. It does not choose a cell in the HumiSeal sheet.
Chemtronics’ guide, retrieved 11 October 2026, says acrylic is the fastest and easiest coating to remove with solvent. It says silicone and urethane coatings “will take more soak-time and will probably require brushing” to fully remove the coating. It says microblasting is most commonly used when removing parylene and epoxy, and that grinding or scraping is a last resort for harder coatings such as parylene, epoxy and polyurethane because serious damage can be incurred. The same section says Chemtronics offers Electro-Wash Two Step, which when heated removes acrylic, silicone and urethane coatings, and that the CircuitWorks Conformal Coating Remover Pen dissolves small areas of coating. Those sentences name Chemtronics products and resin families. They do not name HumiSeal UV40, UV40-250, UV50, UV50LV, UV500 or UV500LV, and they do not split one product into a UV-only state and a full-cure state.
The HumiSeal sheet’s chemical section says its UV coatings can be removed with select strippers after UV cure, before the secondary moisture cure has completed, and then prints a second matrix after full cure. A family sentence does not answer either table.
Takeaway: Keep the Chemtronics family notes and the HumiSeal product cells in separate columns.
Which products and cure states does the HumiSeal sheet cover?
The scope line lists UV40, UV40-250, UV50, UV50LV, UV500 and UV500LV. Table 1 is headed “UV Cure Only” and captioned for coating removal after UV exposure and before moisture cure. Table 2 is headed “UV + Moisture Cure” and captioned for the stripper and coating matrix after full cure (UV+moisture).
The PDF metadata dates the file 10 August 2017. The pages read here do not print a separate issue date or revision letter. This review uses the copy retrieved on 11 October 2026. It is the application sheet for the products it names. It is not a current status for every HumiSeal coating, and it is not a status for a coating from another company.
Table 1 prints the header “UV40-250”. Table 2 prints “UV40 250” with a space. Both tables print “UV50 LV” with a space, while the scope line prints “UV50LV”. The cells below follow each table’s own header. Where the UV500 column prints a capital, the capital is kept.
What does each stripper cell print?
The words below are the words in the two matrices. Each source table has an empty trailing row; that row is omitted. Some “yes” cells in Table 2 are printed in red. The word is recorded. The color is not a separate result. Stripper 1100 carries the footnote that it is not available in the EU.
Table 1, UV cure only, before moisture cure:
| Stripper | UV40 | UV40-250 | UV50 LV | UV500LV | UV50 | UV500 |
|---|---|---|---|---|---|---|
| 1063 | no | no | no | no | no | no |
| 1080 | no | no | no | no | no | No |
| 1080A | yes | yes | yes | yes | yes | Yes |
| 1072 | softened | softened | softened | softened | softened | Softened |
| 1090 | no | no | yes | yes | yes | Yes |
| 1100 | yes | yes | yes | yes | yes | yes |
Table 2, after full cure (UV + moisture). The second header is “UV40 250” as printed:
| Stripper | UV40 | UV40 250 | UV50 LV | UV500LV | UV50 | UV500 |
|---|---|---|---|---|---|---|
| 1063 | no | no | no | no | no | no |
| 1080 | no | no | no | no | no | No |
| 1080A | no | no | no | yes | no | Yes |
| 1072 | no | no | no | softened | softened | no |
| 1090 | no | no | no | yes | yes | no |
| 1100 | yes | yes | yes | yes | yes | yes |
“Softened” is a different printed word from “yes”. This page does not turn it into a time or a pass.
The prose above Table 2 says HumiSeal UV40, UV50LV and UV40-250 can only be removed using Stripper 1100 once the coating has been UV and moisture cured. In Table 2, 1100 is the only “yes” in the UV40, UV40 250 and UV50 LV columns.
The same prose says HumiSeal UV50, UV500 and UV500LV can be removed with the correct HumiSeal chemical stripper, that the recommended strippers are HumiSeal 1080A, 1090 and 1100, and that Table 2 is the coating and stripper combination to use. The table does not print “yes” for every one of those three strippers on every one of those three products:
- UV50, full cure: 1080A is no, 1090 is yes, 1100 is yes, and 1072 is softened.
- UV500, full cure: 1080A is Yes, 1090 is no, 1100 is yes, and 1072 is no.
- UV500LV, full cure: 1080A is yes, 1090 is yes, 1100 is yes, and 1072 is softened.
Read the cell for the named product and the documented cure state. The group sentence does not replace a printed “no” or a printed “softened”. Stripper 1080, without the A, is “no” or “No” in every product column of both tables. Do not treat 1080 and 1080A as the same row.
Takeaway: Copy the cell for the product and cure state you can document. Leave the cell blank when either one is missing.
Which removal figures stay inside that sheet?
The sheet names three removal methods for these UV products: powder micro abrasion, thermal burn-through, and chemical removal. It says all three remove the coating, depending on the process requirements, so that an individual component can be replaced and the area re-coated. That sentence is the sheet’s claim for the products it lists. It is not a method for an unnamed coating. This page does not repeat the chemical application steps.
The abrasion settings are an indication and a starting point for removal of a fully cured film of UV40 at 100 microns dry film thickness. The sheet says thickness, age and substrate quality call for adjustment from that starting point. The printed starting values are Carbo Blast #25, a 0.8 mm nozzle part 1529-32C, air pressure 120 psi, and orifice plate 0.040 x 8 part 3462-9. Those values belong to that UV40 starting point. They are not a thickness or a pressure for the other five products, and they are not a thickness taken from the Chemtronics guide.
The thermal section says the soldering tip needs to be at least 450°C. It recommends soldering through the coating for a short period, under 10 seconds, at a high tip temperature, with about 450°C as a starting point. If the coating does not burn in less than 10 seconds, the sheet says to increase the tip temperature by 20°C. If the coating thickness is greater than 300 microns, it says a longer exposure will be needed and that this risks damage to the solder joint and the solder resist. Those temperatures and times stay with this sheet’s UV products. Chemtronics says burn-through works well with most forms of conformal coating. That general sentence does not move 450°C or the 300 micron note onto another product.
Chemtronics states a typical applied thickness of 1 to 5 mils, which it equates to 25 to 127 microns. That range is Chemtronics’ general statement. It is not the 100 micron starting point or the 300 micron note in the HumiSeal sheet. The two sources are not averaged here.
Takeaway: Record a temperature, time, pressure or thickness only with the product, cure state and file that printed it.
Which repair coating does the sheet name?
After local or complete stripping, the sheet recommends a solvent-based polyurethane such as HumiSeal 1A20 or 1A33 for the repaired area. It says to be sure the coating chosen for local repair is fully cured in accordance with the TDS and will meet the requirements to protect the board in its operating environment. This PDF does not print the 1A20 or 1A33 cure schedule. The cure-time cell stays blank. The recommendation is HumiSeal’s for local repair after stripping the products in this sheet. It does not establish that 1A20 or 1A33 suits a coating the sheet does not name.
The sheet also says flux residue around a reworked area is removed with a recommended cleaning chemistry, then rinsed and dried, before recoating. That paragraph does not name the chemistry. The cleaning-product cell stays blank.
| Field | What the 2017 sheet prints | What stays blank |
|---|---|---|
| Local repair coating | Solvent-based polyurethane such as HumiSeal 1A20 or 1A33 | Any coating the file in hand does not name |
| Cure schedule for 1A20 or 1A33 | Not printed in this PDF; the sheet points to the TDS | Time and temperature for those products |
| Cleaning chemistry before recoat | “A recommended cleaning chemistry”, with no product name | The product name |
| Repair result | Not printed as a test on a named board | Any pass or fail for the board in front of you |
Takeaway: Name 1A20 or 1A33 only as the local-repair examples in this sheet, and leave cure time blank until that product’s TDS is in the file.
How do you patch the coating after a PCB repair?
Patch only when four fields are filled from documents: the product name, the cure state, the removal file that matches that pair, and the repair coating that file names. For the HumiSeal UV sheet, the local repair examples are 1A20 and 1A33, after stripping, inside the scope of that sheet. If the board’s record does not show one of the six product names, or does not show whether moisture cure has finished, do not choose 1A20, 1A33, Stripper 1100 or a remover pen to fill the gap.
Chemtronics’ pen, and the heated Electro-Wash Two Step claim, stay claims about the resin families on that page. They are not a patch specification for a HumiSeal UV product.
Takeaway: A patch material comes from the matching product file, or it is not chosen.
When the original coating is unknown
Stop. Record the product as unknown, the cure state as unknown, the removal file as not identified, and the repair coating as blank. Do not infer the resin from gloss, from a dull patch, or from the age of the board. Do not start powder abrasion, heat or a stripper from the figures above. Do not use this page as instructions for an energized board, or for a control board whose identity is not already on an authorized record.
Give the blank record to a person qualified under the equipment documents and the organization’s rules. The control-board service record is the handoff when the task is identity and permission for installed unattended equipment, not a coating match.
Takeaway: An unknown coating is a blank row, not a guess at the nearest resin family.
When this does not apply
The sheet’s reference list names IPC-HDBK-830A and IPC-7711/7721. Those standards were not read for this page, so this page does not state what they require.
- Coatings outside the six named UV products stay on their own product files. The Chemtronics family notes do not cross-fill those rows.
- Chemical application steps in the HumiSeal sheet are not reprinted here.
- A printed “yes” is the word in the 2017 file for that product and cure state. It is not a repair warranty for a board in front of you.
- East West Manufacturing’s coating-type article and Titoma’s removal overview were in the 11 October 2026 search sample. They discuss resin families. They are not used as cell evidence because they do not print this product-and-cure-state matrix.
Takeaway: Use the cell you can document. Anything outside that file stays off this page.
Methods and sources
This page compiles two public documents. It reports no removal trials and no compatibility tests. The HumiSeal PDF was read in full on 14 October 2026, including both stripper matrices, from the copy retrieved on 11 October 2026. The file metadata dates that PDF 10 August 2017. The pages do not print a separate issue date. Chemtronics’ “The Ultimate Guide to Conformal Coating” on chemtronicseu.com was retrieved on 11 October 2026 and read the same day as this draft; the removal sentences above are that publisher’s general statements. How this reference handles sources is set out in the editorial policy.
Related reading
- Non-invasive control-board service record — Use it when the task is equipment identity and permission, not a coating match.
- Industrial applications route — The reading route this review belongs to.
Next step: Write the product name and cure state from the documents you hold. If either is missing, leave the removal and repair cells blank and give that record to the qualified owner. If both match the HumiSeal UV sheet, read the printed cell and the repair coating named in that sheet, and keep every temperature and time inside that file.
