Phosphorus-containing hydroquinone derivatives, process for their production, phosphorus-containing epoxy resins made by using the derivatives, flame-retardant resin compositions, sealing media and laminated sheets

A method for producing a phosphorus-containing hydroquinone derivative represented by a following general formula (1):

• 19
• (where R1, R2 X, Y and Z are the same as aforementioned):
• comprising reacting at least one compound selected from secondary phosphine derivatives represented by a following general formula (2):
• 20
• (where R1, R2 and X are the same as aforementioned);
• with a benzoquinone derivative represented by a following general formula (3):
• 21
• (where Y and Z are the same as aforementioned).

A method for producing a phosphorus-containing hydroquinone derivative represented by a following general formula (1):

• 22
• (where R1, R2 X, Y and Z are the same as aforementioned):
• comprising reacting at least one compound selected from secondary phosphine derivatives represented by a following general formula (2) and general formula (2a):
• 23
• (where R1, R2 and X are the same as aforementioned);
• with a benzoquinone derivative represented by a following general formula (3):
• 24
• (where Y and Z are the same as aforementioned).