I define a Boolean field with a default value as true, as bellow:

############################################

    bool1 = fields.Boolean('Cant Create as False', default=True)

    bool2 = fields.Boolean('Check to set False the other')

    @api.onchange("bool2")    
    def change_bool2(self):
        if self.bool2 == True:
            self.bool1 = False

###############################3#################

When the user check bool2, the bool1 is set false, as we can expect. 
But, when the user save the change, bool1 return to True again.
With the browser developer tool, in the networking monitor you can see that in the params of the records, it is not include the value bool1: false.

Is there some param that I dismiss to get involve the bool1 in te json sended in the create/write post?

, Best Regards,
Agustín