A printer comprising: a thermal head configured to thermally transfer ink of an ink ribbon to a label; a platen roller provided opposite to the thermal head; a ribbon transport unit configured to transport the ink ribbon between the thermal head and the platen roller; a transport unit configured to transport a sheet carrying the label and a mount between the thermal head and the platen roller such that a printed surface of the label and the thermal head face each other across the ink ribbon; a clamping mechanism configured to clamp the ink ribbon, a printing area of the label, and the sheet between the thermal head and the platen roller; an acquisition unit configured to acquire first print data to be printed on a first label and second print data to be printed on a second label, the second label being adjacent to the first label on the sheet; a non-printing area calculation unit configured to calculate a dimension of a non-printing area on the sheet, based on the first print data and the second print data; and a control unit configured to control the clamping mechanism to separate the ink ribbon from the sheet and stop transport of the ink ribbon by the ribbon transport unit, when the transport unit transports the non-printing area on the sheet between the thermal head and the platen roller, characterized in that: the non-printing area is an area between a last printing area of the first print data and a first printing area of the second print data, including a gap (g) which is a portion having only the mount between the first and the second labels, and when the non-printing area has a dimension not less than a predetermined threshold along a transport direction of the sheet, the control unit separates the thermal head and the platen roller from each other by the clamping mechanism, and stops transport of the ink ribbon by the ribbon transport unit. a thermal head configured to thermally transfer ink of an ink ribbon to a label; a platen roller provided opposite to the thermal head; a ribbon transport unit configured to transport the ink ribbon between the thermal head and the platen roller; a transport unit configured to transport a sheet carrying the label and a mount between the thermal head and the platen roller such that a printed surface of the label and the thermal head face each other across the ink ribbon; a clamping mechanism configured to clamp the ink ribbon, a printing area of the label, and the sheet between the thermal head and the platen roller; an acquisition unit configured to acquire first print data to be printed on a first label and second print data to be printed on a second label, the second label being adjacent to the first label on the sheet; a non-printing area calculation unit configured to calculate a dimension of a non-printing area on the sheet, based on the first print data and the second print data; and a control unit configured to control the clamping mechanism to separate the ink ribbon from the sheet and stop transport of the ink ribbon by the ribbon transport unit, when the transport unit transports the non-printing area on the sheet between the thermal head and the platen roller, characterized in that: the non-printing area is an area between a last printing area of the first print data and a first printing area of the second print data, including a gap (g) which is a portion having only the mount between the first and the second labels, and when the non-printing area has a dimension not less than a predetermined threshold along a transport direction of the sheet, the control unit separates the thermal head and the platen roller from each other by the clamping mechanism, and stops transport of the ink ribbon by the ribbon transport unit. the non-printing area is an area between a last printing area of the first print data and a first printing area of the second print data, including a gap (g) which is a portion having only the mount between the first and the second labels, and when the non-printing area has a dimension not less than a predetermined threshold along a transport direction of the sheet, the control unit separates the thermal head and the platen roller from each other by the clamping mechanism, and stops transport of the ink ribbon by the ribbon transport unit.