FAIRFIELD, Conn.--(BUSINESS WIRE)--Acme United Corporation (NYSE MKT:ACU) today announced that net sales for the second quarter ended June 30, 2015 were $34.0 million, compared to $33.4 million in the comparable period of 2014, an increase of 2%, or 4% in constant currency. Net sales for the six months ended June 30, 2015 were $56.8 million, compared to $52.5 million in the same period in 2014, an increase of 8%, or 10% in constant currency. Net income for the quarter ended June 30, 2015 was $2