What do you mean by keep the line pure ? do you plan to health test him before you stud him out ? I highly recommend it before breeding. I would not want to bring unhealthy pups into the world
Anyways I am not parti breeder but this is my experience with parti colored cats.
There is really no gene called parti its just called S for spotting gene. Like new poodlemum said the dogs will probably be mismarked.
I have a parti colored cat in fact 2 .when bred to a solid cat you get less white on some kittens , the chances of getting a solid kitten is low. We would get 1-2 solids out of 6 kittens.
Here is some pictures Here is the queen
See how much white she had.
Here is the dad He as no white what so ever !