Method for manufacturing sheet-shaped packaging materials

Abstract

The invention provides a method for manufacturing sheet-shaped packaging materials. The method comprises the following steps: expanding a paper core layer and punching an opening hole, wherein a fiber direction of the paper core layer extends along the length direction; printing a printing layer on the outer surface of the paper core layer; extending a pattern and character direction of the printing layer along the width direction of the paper core layer; extruding and laminating a thermoplastic material on the printing layer to form an outermost layer; extruding and laminating a thermoplastic material on the inner side face of the core layer to form an intermediate layer; compounding a barrier layer on the inner side face of the core layer by the intermediate layer; extruding and laminating a thermoplastic material on an aluminum foil layer to form a binding agent layer; extruding and laminating a thermoplastic material on the binding agent layer to form an innermost layer; pressing a vertical fold line, a transverse fold line and an inclined fold line on one side of the outermost layer; and slitting a continuous packaging material of the plurality of sheet-shaped packaging materials to form the single-sheet packaging materials. The packaging materials can have a relatively good fold line effect by using relatively small pressure when the fold lines are pressed.

Description

technical field [0001] The invention relates to a method for manufacturing a packaging material for packaging food, in particular to a method for manufacturing a sheet-shaped packaging material for packaging liquid food. Background technique [0002] At present, for fresh milk, yogurt, fruit juice, wine, tomato sauce and other pourable liquid foods, square and triangular packages are generally used. There are many kinds of materials for this package, and composite materials are generally the most commonly used. Common composite materials include at least the following layers: outermost layer of thermoplastic material, printing layer, support layer, middle layer of thermoplastic material, barrier layer, adhesive layer and innermost layer of thermoplastic material. [0003] The outermost layer of thermoplastic material is used to provide effective protection for the liquid food in the packaging, preventing moisture and liquid from intruding into the packaging material; the pri...

AI Technical Summary

Problems solved by technology

However, even if the crease line is pre-set on the core layer, the crease line will be flattened by the pressure roller or the crease line will become shallower during the subsequent composite lamination process of each thermoplastic material layer of the laminated packaging material. Make the folding molding effect worse

This is because the composite packaging material has a certain thickness. When the pressure of the creasing device is small, the effect of the crease line on the composite packaging material is not obvious, which is not conducive to the subsequent folding and packaging forming; when the pressure of the creasing device is large At this time, the composite packaging material will generate a large stress at the indentation. At this time, if the support layer uses fiber material, the fiber material will be easily stretched at the fold and there is a danger of cracks. When the tensile stress is large, The innermost layer of thermoplastic material and the aluminum foil layer in the composite packaging material will have the risk of cracking, causing leakage of the packaging container and the risk of invalidating the aluminum foil layer

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