Paper Cutting Method for Paper Handbags
There is an approximately 1cm gripper margin on the printed sheet where printing cannot be applied. Beyond the finished product area, register marks, color marks, and other positioning elements are also required. For general printing jobs, the paper is first cut larger than the finished size; after printing, the excess edges are trimmed off with a paper cutter or die-cutting machine.
In creasing processing for paper handbags, if thick cardboard is used instead of creasing matrix, die-cutting and creasing should not be performed simultaneously. Therefore, paper handbags usually only undergo creasing without die-cutting.
If the paper edges are trimmed with a paper cutter before creasing, the positioning accuracy during creasing will be affected. If trimming is delayed until after die-cutting, paper deformation during pressing can prevent clean and even cutting.
Manufacturing Process of Paper Handbags
For this reason, the common practice is to cut the paper to the full unfolded size of the finished product before printing. After printing, only creasing is performed, with no further trimming or die-cutting required. This method saves both die-making costs and paper consumption, while streamlining production efficiency.
Reuse of Die-Cutting Plates
In most cases, paper handbags are not used for direct product packaging. Instead, products are first placed in boxes or plastic bags and then inserted into handbags for easy carrying and an elegant appearance. As a result, customers’ dimensional accuracy requirements for handbags are often less strict than those for cartons.
Based on this characteristic, we have accurately compiled and summarized the length, width, and height dimensions of all paper handbags previously produced in our factory, and classified and numbered them according to different heights.
For example, handbags with heights ranging from 25cm to 30cm are grouped into one category. The die plates for all handbags within this height range are numbered, stored in sequence, and recorded with their exact dimensions (length, width, height), layout format, and the distance from the gripper edge to the fold crease line of the handle area.
When a customer places an order for paper handbags, we first check the record sheet. If an identical size is available, we use the existing die directly. If only similar sizes exist, we may consult with the customer to see if production with the similar size is acceptable.
If approved, we proceed with plate-making and printing based on this size, then reuse the existing die plate for creasing. This significantly saves die-making cost and time, generating considerable economic benefits for high-volume paper bag manufacturers.
For handbags that require new die plates, the new plates should follow a unified layout and a fixed distance from the gripper edge to the handle fold crease. After use, they should be promptly classified, registered, and stored for future reuse.
Die-Cutting Method 1: Creasing on the Reverse Side of the Paper
During folding after die-cutting, some creases require the printed side to fold outward, while others fold inward.
The most vulnerable areas of paper handbags during use are the four edges of the rectangular bottom and the four vertical creases — all of which involve folding with the printed side outward.
To reduce damage during folding, creasing for paper handbags is preferably done on the reverse side. That is, the creasing rule contacts the back of the paper, making the crease protrude toward the printed side.
Since the crease lines must align precisely with the front printed image, the gripper and side guide positions during printing must be consistent with those during die-cutting.
Die-Cutting Method 2: Using Thick Cardboard Instead of Creasing Matrix
To ensure easy folding without cracking, the following points must be observed:
- The backing sheet must have sufficient thickness.
- Pre-crease grooves into the backing sheet before formal production.
- Apply appropriate pressure during formal die-cutting.
- Paper folds more easily along the grain direction, requiring lower pressure; against the grain, higher local pressure may be needed.
Most paper used for handbags is coated paper or kraft paper below 250g/m², and final folding is usually done manually.
Therefore, creasing for paper handbags generally does not require standard creasing matrix matched with steel rules. Instead, thick cardboard is used as a substitute. The specific procedure is as follows:
- Clean the base plate of the die-cutting machine, apply double-sided tape, and attach a layer of thick cardboard (about 500g/m²) firmly to the plate.
- Use relatively high pressure to run the machine and crease the thick cardboard repeatedly until deep, clean grooves form — take care not to crack the board.
- Reduce the die-cutting pressure, feed the paper, and crease the fold lines.
The creases must be deep enough to prevent shifting during manual folding, but not so deep that the paper breaks, cracks after folding, or suffers excessive plastic deformation that shortens the service life of the bag.Particularly for kraft paper, which is more brittle and less flexible than coated paper, precise control of die-cutting pressure is essential.
