Yes, you're correct that exposure to a humid environment might have caused some moisture buildup or corrosion, which in turn, can cause display issues on your laptop.
Before you proceed, please note that this process can void any warranty, including extended warranties, you may have on your Dell Inspiron N7110. If you're not comfortable with doing this yourself, I would suggest taking it to a certified technician.
If you feel comfortable going ahead, here are the steps to clean the corrosion with ISO alcohol:
1. **Turn off the laptop and unplug it from the power source**. Remove the battery if possible.
2. **Open the laptop case**. You'll want to refer to the service manual for your Dell Inspiron N7110 to see how to safely do this. You can typically find these manuals on the manufacturer's website.
3. **Inspect the internals for visible signs of corrosion or moisture**. This could be on the motherboard, the graphics card, or other components.
4. **Apply the ISO alcohol**. Use a soft cloth or a clean toothbrush to gently apply the ISO alcohol (90% or higher is preferred) to the affected areas. This will help remove any corrosion and dry out moisture. Do not pour or spray the alcohol directly onto the components.
5. **Allow the laptop to dry**. Make sure it's in a cool, dry environment. This could take several hours, but it's crucial to ensure all the alcohol and any remaining moisture has evaporated before you put the laptop back together.
6. **Reassemble the laptop**.
7. **Test the laptop**. If the display isn't working correctly, you may have an issue with a specific component that may need to be replaced.
Bear in mind that this process may not necessarily solve the issue. If the humidity has damaged the display or other components beyond cleaning, replacement parts may be required. In such cases, it's best to seek professional help.
Always make sure to keep your laptop in a dry and cool environment to prevent moisture damage. Even if not using it for a prolonged duration, store it safely to prevent any such accidents.