Mention industrial product obtained from HCHO.

Explanation

### Step-by-Step Solution:

1. **Identify the Compound**: The industrial product we are looking for is derived from Formaldehyde, which is represented by the chemical formula HCHO.

2. **Reaction with Phenol**: Formaldehyde reacts with phenol in the presence of a base. The base facilitates the reaction by abstracting a hydrogen atom from phenol, resulting in the formation of a phenoxide ion.

3. **Formation of Phenoxide Ion**: The phenoxide ion increases the electron density on the carbon atom adjacent to the hydroxyl group (OH) of phenol, making it more reactive towards electrophiles.

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