1. Classification of base paper
1.1: Corrugated base paper (corrugating medium)
The national standards are divided into four categories: A, B, C, and D. D-grade corrugated paper is basically eliminated by the market, and few manufacturers buy and use it.
1.2: Linerboard
1.2.1: Kraft cardboard (US card, Russian card). Features: long fiber, heavy sizing, high physical strength, rough board; pure wood pulp or a small amount of OCC. Abbreviation: Imported cattle card.
1.2.2: Imitation kraft cardboard. Features: 15-25% wood pulp is hung on the surface, and the rest is OCC; the fiber is shorter and the strength is worse than that of kraft cardboard. The paper surface is smooth, with different degrees of sizing (water absorption ranging from 30-55g/m2), and surface dyeing treatment. Abbreviation: Domestic cattle card.
1.2.3: White cardboard. White-faced cow card bottom, bleached wood pulp on the surface, and the rest are natural or dyed wood pulp. (Russian white, Swedish white card, Finnish white card); white board paper (surface bleached wood pulp, the rest are deinked or non-deinked waste paper); coated white board paper (white on white, white on gray background, ---) .
1.2.4: Recycled paper. All composed of OCC, but different from corrugated paper. The surface is 11# or more AOCC noodles and has been dyed). The market is generally called C-grade containerboard, and some are called T paper.
2. Basic properties of carton base paper.
2.1: Physical indicators: quantitative, moisture, tightness, bursting strength (bursting index), ring pressure strength (ring pressure index), positive/reverse water absorption, and folding resistance.
2.2: Appearance indicators: smoothness, color difference, whiteness.
2.3: Reference for specific base paper standards: GB13023 (national standard for corrugated paper), GB13024 (national standard for container board). Related projects refer to the latest industry trends or standards.
3. The basic production process of papermaking
3.1: Traditional papermaking process: Raw material: wood or grass fiber.
3.2: Modern papermaking process: Raw materials: commercial wood pulp, waste paper.