if you want to escape double quote in JSON use \\ to escape it.
example if you want to create json of following javascript object
{time: '7 "o" clock'}
then you must write in following way
'{"time":"7 \\"o\\" clock"}'
if we parse it using JSON.parse()
JSON.parse('{"time":"7 \\"o\\" clock"}')
result will be
{time: "7 "o" clock"}