The Rigid Box Manufacturing Process
There are three main materials used in making a rigid box; cardboard, paper, and the filler. These three components come together in the tightwrapping machine process that combines these materials to create your box.
The cardboard provides the basic structure to your box. You determine the size of your box by measuring the base of the box from score line to score line. This size is normally stated as Length x Width x Height of base x Height of lid. Don’t worry about giving the exact size of the lid (excepts it’s height) since we will determine its size from the base and the type of cardboard you are using to guarantee a good fit.
Cardboard is normally described by its color and thickness. Plain board (which normally is gray in color) is the least expensive and used for mailing boxes and other boxes that are created more for function than appearance. White board is normally used for decorative boxes such as jewelry boxes (most white board is gray on the other side but this is covered by the paper being laminated to the box). Colored board such as Black is used when you want to coordinate the color of the paper to the color of the board. Most colored boards require larger orders to meet mill requirements. Black board tends to be more common and can sometimes be found for smaller runs.
The thickness of the board is normally measured in thousandths of an inch. Most jewelry boxes are manufactured using .030 board, while mailing boxes are manufactured using .042 or thicker board. Normally the larger the box, or the heavier the item that is being placed in the box requires a thicker board.
Once you know the size of the box, the color of the board and its thickness, we compute the exact size of the cardboard blanks that will form the structure of the box. A die is created which will cut the individual base and lid parts out of a larger piece of cardboard. For smaller runs a scoring machine can be used the cut the base and lid of the box out of a sheet of cardboard.
The best thing about a rigid box is that you have infinite combinations of papers that you can select to wrap the box. Several paper mills (i.e. Sullivan Papers) manufacture paper especially made for the rigid-box industry. You can also choose a variety of fine printing papers available on the market. You must be sensitive to the weight of the paper you choose. Paper that is too light or heavy won’t wrap properly around the box. We can normally wrap kraft papers that are noted as 40 lb. to 50 lb. papers. Litho or text papers are chosen weighing 55 lb. to 70 lb.
The paper is sheeted from rolls into large sheets of paper that are then cut down into smaller pieces of paper which correspond to the size of your box. Special mitering machines are then used to cut the corners out of the paper so that they properly wrap around the box.
When you are having your boxes hot stamped, these small individual pieces of paper are hot stamped at this point in time or for larger runs they are stamped on a much larger sheet (multiple-out) and then cut down into the individual pieces.
When your box is being printed, a layout is created for the bases and lids of the box on a large sheet of paper that can accommodate multiple parts. Once the large sheet of paper is printed, it is normally coated with a varnish or aqueous coating to protect the images from rubbing off the paper. These large sheets of paper are then cut into the individual smaller pieces of paper that correspond to the size of your box.
Many different types of fillers can be chosen for your box. Cotton is a popular filler for costume jewelry boxes and foam is sometimes used for higher quality items. A pad is perfect when you want to hold multiple items in place in the box to guarantee its placement when the box is opened. Platforms are sometimes used in the base of the box to hold a gift certificate. Vac form inserts tend to be the most expensive and are used when you have to prop the item up in the box.
All of the materials mentioned above come together in the tightwrapping process. One machine will make the lid of the box, and other will make the base of the box. In between these two machines is a conveyor belt that allows us place your desired filler in the box and to pack up the box.
The cardboard is first placed in a bender that bends up the four sides of the box. The paper is placed in a gluer that coats the underside of the paper with a thin layer of sulfur-free anti-tarnishing glue.This paper travels down a conveyor belt to the bender where a computer picks up the cardboard and places it on top and in the center of the paper. This semi-completed box then travels further down the belt to the wrapping machine that presses the glued paper around the box tightly to form a rigid box.
The base of the box travels down a conveyor where the filler is added and then we put the lid on top of the base and then pack the completed box in corrugated cartons. Wasn’t that simple!