Paper Selection Guide for Paper Bag Machines (With Handle / Square Bottom / Pointed Bottom)
Paper is the core raw material for paper bag production. Its material, grammage, thickness and physical properties directly determine the load-bearing capacity, appearance, practicality and production cost of finished paper bags. It is also closely related to the compatibility with fully automatic paper bag machines for handle-attached, square-bottom and pointed-bottom bags. Due to differences in forming principles, production processes and end-use applications, paper bag machines of different types have distinct requirements for paper. Proper paper selection can maximize equipment efficiency, reduce material waste, and enable finished paper bags to perfectly fit application scenarios while enhancing market competitiveness. Combined with the characteristics of the three mainstream fully automatic paper bag machines, this guide elaborates on the key points of paper selection to provide practical references for industry practitioners.
1. Fully Automatic Handle-Attached Paper Bag Machine
This machine is mainly used to produce handheld paper bags, widely applied in retail shopping, gift packaging, garment packaging and other scenarios. Paper selection must balance load-bearing performance, toughness and aesthetics, while adapting to the handle laminating process to prevent problems such as handle detachment and paper tearing. The core paper requirements focus on toughness, stiffness and process compatibility. Kraft paper and white kraft paper are the preferred options; specialty paper can be adopted for high-end customized demands.
In terms of material, kraft paper is the cost-effective choice, divided into regular kraft paper and white kraft paper. It features high toughness, tear resistance and excellent load-bearing capacity, and supports simple logo and pattern printing, suitable for most retail and gift scenarios. Specialty paper (such as matte paper and textured paper) is ideal for high-end customization to upgrade bag texture, yet it comes with higher cost. Attention should be paid to its compatibility with the handle laminating process, as overly brittle paper may cause weak lamination.
For grammage, the paper weight for fully automatic handle-attached paper bag machines is controlled within 80–150 g/m², adjusted according to bag applications:
Small gift bags & garment bags: 80–100 g/m², balancing light weight and aesthetics;
Medium shopping bags: 100–120 g/m² for reliable load-bearing;
Large shopping bags & heavy-duty packaging bags: 120–150 g/m²; lamination can further improve load-bearing and waterproof performance.
In addition, paper thickness must match the creasing and laminating modules of the machine. Excessively thick paper leads to unclear creases and loose handle lamination, while overly thin paper is prone to tearing and deformation.
2. Square-Bottom Paper Bag Machine
Square-bottom paper bag machines produce flat-bottom self-standing paper bags, suitable for food, daily necessities, express packaging and other scenarios, especially for products requiring shelf display such as snacks, dry goods and small daily items. Paper selection prioritizes stiffness, load-bearing capacity and sealing performance. Kraft paper and composite paper are the primary choices; oil-proof and waterproof materials are required for food-grade applications.
Square-bottom paper bags need to stand upright independently, placing extremely high demand on paper stiffness. Ordinary thin paper easily collapses, so the recommended grammage is 80–100 g/m².
Food packaging (bread, dry goods): Oil-proof coated kraft paper is preferred, with the coating layer blocking oil and moisture penetration to avoid softening and damage;
Express packaging: Thickened kraft paper (80–120 g/m²) with lamination to enhance tear resistance and waterproof performance, resisting extrusion and friction during logistics transportation;
Daily necessities packaging: White or colored kraft paper for both aesthetics and practicality.
It is worth noting that paper must have qualified toughness to avoid breakage during edge folding and bottom sealing. High-density, high-toughness premium paper is recommended.
3. Pointed-Bottom Paper Bag Machine
Pointed-bottom paper bag machines specialize in manufacturing pointed-bottom self-standing paper bags, mainly used for bakery, fast food, agricultural product packaging such as baguettes, bread, fried dough sticks and dry goods. Paper selection focuses on oil resistance, air permeability (for partial food scenarios) and forming stability. Oil-proof coated paper and kraft paper are preferred to adapt to the edge folding and bonding process of pointed bottom forming.
Bakery and fast food are the main application scenarios for pointed-bottom paper bags, where oil resistance is a top priority. Oil-proof coated kraft paper or oil-proof coated white kraft paper with a grammage of 80–120 g/m² is recommended, ensuring oil resistance and stable pointed-bottom forming. For baguettes and long bread, breathable oil-proof paper is adopted to prevent dampness and mildew, with sufficient toughness to avoid tearing during packing and handling. For agricultural products such as dry goods and grains, regular kraft paper of 60–80 g/m² is used to balance load-bearing performance and cost efficiency.
Moreover, pointed-bottom forming requires high paper flatness. Paper with no surface wrinkles and uniform thickness must be selected to prevent skewed forming and weak bonding of the pointed bottom.
General Principles for Paper Selection
Beyond the targeted requirements for the three types of machines, the following general principles should be followed:
Equipment Specification Compatibility: Different models of fully automatic paper bag machines have clear requirements for paper width and roll diameter. Confirm equipment parameters in advance to avoid incompatible paper materials.
Cost Control: Select appropriate paper material and grammage based on end-use demands, and avoid unnecessary cost increases from over-specifying high-end materials.
Environmental Compliance: Driven by global plastic ban policies, prioritize degradable and renewable paper such as recycled kraft paper to meet regulatory requirements and enhance brand environmental image.
Printing Adaptability: For printed paper bags, choose paper with a smooth surface and good ink absorption to ensure clear and durable printed patterns.
Conclusion
Paper selection for fully automatic handle-attached, square-bottom and pointed-bottom paper bag machines requires comprehensive consideration of equipment characteristics, end applications, usage scenarios and budget. Rational paper selection not only improves production efficiency and reduces material loss, but also optimizes the load-bearing performance, appearance and practicality of finished paper bags. It helps industry practitioners seize opportunities in the packaging market amid the advancement of environmental protection policies.
