Fifth , hardcover book shell quality requirements
According to the national standards CY/T27-99, the quality of hardcover shells should meet the following requirements.
(1) The size of the middle seam. When the thickness of the cardboard is 1.5-3.0mm, the width of the middle seam is 7-10mm.
(2) Wide in diameter. The diameter of the round-backed shell is the length of the arc of the circle and two widths of the middle seams; the width of the middle of the square-backed shell is the width of the back of the book plus the width of the two slits. The width of the median diameter of the square back ridge should be added to the thickness of two cardboards.
(3) Floating mouth width. Floating mouth width of 2 ~ 4mm.
1. The book shell is made of animal parts or synthetic resin glue with less moisture, fast drying, and strong bonding.
2. The bookcase cardboard and middle diameter cardboard combination is correct and the dimensional error is: length ≤ 1.5mm, width ≤ 2.5mm.
3. The book case should be face-to-face stacked, flattened, and naturally dried after being transported. Drying and drying should not be allowed.
4. Hot stamping, clear pattern, no paste version, flower color, hot foil firmly, good gloss.
5. Press and embossing should be clear.
6. Based on the back center line of the book, the error range of the book backing is as follows:
Back thickness error range
≤10mm ≤1.0mm
>10,≥20mm ≤2.0mm
>20, ≤30mm ≤2.5mm
>30mm ≤3.0mm
Source: Bison
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