Samples before cleaning. The surface of the aluminum bottle is coated with liquid (polyester or acrylic), and the inside is also coated (silicon system). All heat-cured.

Use the special water-based paint stripper AHLR03-D2 for aluminum alloy, heat the agent to 60~70℃, put it into an aluminum bottle and soak it. The inside of the aluminum bottle also needs to be injected with the agent AHLR03-D2.

It was found that the aluminum bottle was placed in the aluminum alloy water-based paint stripper AHLR03-D2 heated to 60~70°C, and after about 5 minutes, the surface coating began to swell. After about 10 minutes, the surface coating was completely peeled off. The appearance of the aluminum bottle was not damaged or discolored.

The ink on the bottom of the bottle and the depression of the font is thicker, so extend the soaking time to 15-20 minutes. The depressions are removed with a nylon brush. Finally, take it out and wash it with clean water. Pay attention to the final flushing water, please flush with pure water (or RO water with conductivity <5ppm), to avoid chlorine ions in tap water or iron and calcium ions in groundwater from causing lesions on the aluminum alloy surface in the future. After the inside of the aluminum bottle was rinsed with water, it was found that the silicon coating was not damaged at all.

This test also tested the water-based paint stripper AHLR03-D2plus for aluminum alloys, and found that AHLR03-D2plus has better ink removal ability. After heating the agent to 60~70°C, put it into an aluminum bottle to soak. It takes about 2-5 minutes to completely remove. AHLR03-D2plus will not harm aluminum alloy either. But AHLR03-D2plus will damage the silicon coating inside the aluminum bottle.

It cannot be seen that the inner coating is thicker, but it will be found that the water repellency of the inner silicon coating has deteriorated.

Repeat the test: put AHLR03-D2plus into an aluminum bottle, heat it to 120°C for about 20 minutes, and the silicon ink inside can be completely removed.

but found a problem：

7.1 For external acrylic paint, heat the agent to 120°C. It is completely removed in about 1 minute.
7.2 The exposed aluminum bottle can only withstand boiling for about 5 minutes without being injured when it comes into contact with the medicine at high temperature. After more than 5 minutes, the color of the aluminum bottle was gradually seen. (It means that the aluminum bottle will not be injured for only about 5 minutes under the contact of AHLR03-D2plus.)

in conclusion：

8.1 Use the special water-based paint stripper AHLR03-D2 for aluminum alloy, which can effectively strip the coating on the outside of the aluminum bottle, and the silicon coating inside the aluminum bottle will not be affected at all. It will not harm the aluminum alloy either.
8.2 The water-based paint stripper AHLR03-D2plus for aluminum alloy has better ink removal ability, but it will damage the silicon coating inside the aluminum bottle. It is only recommended if you want to remove the paint inside and outside the aluminum bottle at the same time.
8.3 In order to prevent the aluminum bottle from being soaked in AHLR03-D2plus for a long time and cause damage to the aluminum bottle, it is recommended to put the used AHLR03-D2 outside and put AHLR03-D2plus inside the bottle. In this way, the overflowing AHLR03-D2plus can be diluted by the used AHLR03-D2, and the attack power will not be too strong.
Or put AHLR03-D2plus in the bottle and lock the cap. Put it in an oven to heat, or put it in a basket and soak it in AHLR03-D2 medicine to heat it. Then take off the lid, pour out the medicine and recycle it. Finally, rinse the bottle with clean water.