In brief: Acetone and isopropanol only dissolve deep primer residues on acrylic and hybrid primers, not on silicate or mineral substrates. Both solvents are also highly flammable, hazardous to health, and attack paint, plastic, and joints. The HATOCH pH7 Stick (pH-neutral, no hazardous substance labeling, utility model DE 20 2021 105 495, NSF-certified) removes deep primer gently from acrylic/hybrid primer and has a significantly higher flash point of 65°C than acetone or isopropanol. For silicate and mineral substrates, there is the SPECIAL 500ml variant based on citric acid (pH 2–4) – also without hazardous substance labeling, but with a different mode of action than the neutral stick.
→ Directly to the right product: HATOCH pH7 Stick 50ml (acrylic/hybrid primer) or HATOCH SPECIAL 500ml (all primer types).
The problem with the "standard recommendation"
Acetone and isopropanol are classic solvents that can dissolve many synthetic resin and acrylic binders. This works – but only under certain conditions:
- Only for acrylic or hybrid deep primer. For silicate-based or mineral primer, both solvents are ineffective – the chemical bonding is completely different.
- Highly flammable. Both substances have a very low flash point (acetone approx. -20°C, isopropanol approx. 12°C). In indoor areas without strong ventilation, this is a real safety risk.
- Aggressive towards the environment. Paint, plastic floors, joints, seals – anything that comes into contact can be attacked or discolored.
- Health hazard. Strong fumes, irritating to eyes and respiratory tract, unsuitable for prolonged work without respiratory protection.
- No targeted approach. It doesn't dissolve selectively but rather "etches through" chemically – this increases the risk of substrate damage.
The more targeted alternative
The HATOCH pH7 Stick was specifically developed for acrylic and hybrid deep primer – pH-neutral, without hazardous substance labeling, NSF-certified and utility model protected (DPMA DE 20 2021 105 495). With a flash point of 65°C, it is significantly above room temperature and thus far above that of acetone or isopropanol. For silicate or mineral substrates, the stick is not sufficient – here, the SPECIAL 500ml variant comes into play, which works on a citric acid basis (pH 2–4) and thus covers all primer types.
Important for an honest classification: Both HATOCH products work on different principles – the stick is pH-neutral, the SPECIAL variant is slightly acidic due to citric acid. Both do not carry hazardous substance labeling and are significantly more material-friendly than classic solvents like acetone, but they must not be mixed.
Comparison table
| Criterion | Acetone / Isopropanol | HATOCH pH7 Stick (50ml) | HATOCH SPECIAL (500ml) |
|---|---|---|---|
| Works on acrylic/hybrid primer | Yes | Yes | Yes |
| Works on silicate/mineral primer | No | No | Yes |
| pH value | Strongly solvent-based | Neutral (pH 7) | Acidic, citric acid-based (pH 2–4) |
| Flash point | Very low (Acetone approx. -20°C, Isopropanol approx. 12°C) | 65°C | 65°C |
| Material compatibility (paint, plastic, joints) | Risk of dissolution/discoloration | Material-friendly | Material-friendly with proper application |
| Odor nuisance | Strong, irritating | Low | Low, slightly acidic |
| Certification | – | NSF-certified | NSF-certified |
| Indoor use without strong ventilation | Not recommended | Suitable | Suitable |
| Combination with pH7 Stick | – | Do not mix with SPECIAL (risk of formaldehyde formation) | Do not mix with pH7 Stick (risk of formaldehyde formation) |
Read more
- SPECIAL 500ml or pH7 Stick: Which product do I need?
- Identify acrylic, hybrid, or silicate deep primer
- Why nitro thinner and white spirit are not a good idea
Frequently Asked Questions (FAQ)
Can deep primer be removed with acetone?
Only partially. Acetone dissolves acrylic and hybrid deep primer, but does not work on silicate or mineral substrates. In addition, acetone is highly flammable and can attack paint, plastic, and joints.
Is isopropanol better suited than acetone?
Isopropanol has the same limitations as acetone: It only works on acrylic/hybrid primer, is flammable, and not material-friendly. A HATOCH remover without hazardous substance labeling is the safer alternative.
Which agent removes deep primer on all substrates?
For acrylic and hybrid deep primer, the HATOCH pH7 Stick (50ml, pH-neutral) is sufficient. For silicate and mineral substrates, the HATOCH SPECIAL 500ml variant (citric acid-based, pH 2–4) is necessary, as it covers all primer types.
Is the HATOCH Deep Primer Remover highly flammable?
No. Both products have a flash point of 65°C – significantly above room temperature and far above that of acetone (approx. -20°C) or isopropanol (approx. 12°C). In everyday use, they are therefore uncritical, even if a flash point is fundamentally present.
Can HATOCH SPECIAL be mixed with the pH7 Stick?
No. The SPECIAL variant is citric acid-based (pH 2–4) – combining it with the pH-neutral pH7 Stick carries a risk of formaldehyde formation and should be avoided.
Conclusion
Acetone and isopropanol are not a "trick" but a compromise with side effects: limited effectiveness, fire hazard, material risk. Anyone who frequently deals with deep primer residues – professionally or privately – will be safer and more predictable with a specifically developed HATOCH solution.
Important note: Do not mix SPECIAL products with the pH7 Stick – there is a risk of formaldehyde formation when combining acid and the pH-neutral stick.