The hottest packaging paper and paperboard III

Packaging paper and paperboard (III)

III. processing paper and paperboard

1. Processing paper

in the field of packaging, due to the increasingly high requirements for the packaging function of paper materials, many new types of paper and paperboard came into being. These new types of paper and paperboard are processed paper or processed paperboard made through secondary processing. The so-called secondary processing refers to the physical or chemical processing of paper or paperboard, giving them special properties to meet special needs. These special properties mainly include the following aspects:

(1) protection, including waterproof, moisture-proof, grease proof, organic solvent proof, and improving barrier and air tightness

(2) improve mechanical strength

(3) improve operation adaptability, such as sealing

2. Common processing paper for packaging

(1) asphalt waterproof paper. Asphalt waterproof paper is made by coating asphalt on paper. It is the earliest waterproof and moisture-proof material

(2) wrinkle waterproof paper. This is the most common kind of waterproof paper. It is coated with waterproof agent on the base paper, so it has waterproof

performance. After wrinkle processing, it has vertical and horizontal scalability, and there are wrinkle waterproof paper with only longitudinal scalability

(3) paraffin processed paper. Paraffin processing paper is divided into surface coating processing paper and overall IMPREGNATION processing paper. When making paper containers such as paper

boxes, cartons or paper cups, paraffin processing is usually carried out after printing and other processing

(4) polyethylene processing paper. Almost all paper and paperboard can be processed into polyethylene processing paper, which is not limited to one side of the paper, but also can be coated on both sides of the raw paper, and polyethylene can also be sandwiched between two layers of raw paper to make thick paper. The most basic manufacturing method is the "extrusion coating" method, which is to press polyethylene directly from the extruder to the surface of the raw paper in the state of hot-melt film. After pressing, it will quickly make every effort to build a domestic first-class photoelectric film material R & D base for cooling, so that it can closely fit with the raw paper

(5) polyvinylidene chloride processing paper. This is a kind of processing paper coated with vinylidene chloride and vinyl chloride copolymer. The manufacturing method of this processing paper is generally to coat the emulsion of polyvinylidene chloride resin on the paper surface and then dry it. In order to obtain a high-quality coating, it is necessary to repeatedly apply it for 2-7 times. The raw material paper for manufacturing PVDC processing paper should try to choose the paper with dense texture and smooth surface, because the price of PVDC is high. In this sense, cellophane is the most suitable kind of paper, and high-quality kraft paper can also be used as processing raw material paper

PVDC processing paper has excellent air tightness, good oil resistance and moisture resistance, good heat sealing, and good printing adaptability on the coated surface

(6) heat sealing cellophane. Cellophane has no heat sealing property, which limits its application. Applying thermoplastic polymer materials, such as polyvinylidene chloride and polyvinyl acetate, to paper or cellophane substrate can make it have heat sealing property and increase moisture resistance and gas resistance

polyvinylidene chloride processing paper with cellophane as raw material is heat sealable cellophane. In addition, other processed paper with cellophane as raw material is also mainly to improve heat sealing, or to meet the needs to improve moisture resistance. Therefore, it is also decided to adopt the single arm type, and the coating used is the copolymer of polyvinyl acetate series and other appropriate resins

(7) stripping paper. Stripping paper, also known as "separation paper", is easy to peel from sticky substances. It is processed by coating talc powder or clay powder on the surface of raw paper with appropriate adhesive. It is used to pack viscous substances such as asphalt and rubber

(8) adhesive coated paper. This refers to the processing paper made by coating a layer of water activated adhesive or pressure-sensitive adhesive on the back of the paper tape, seal or label, that is, adhesive tape paper or self-adhesive paper

(9) rust proof paper. The antirust effect can be achieved by coating the raw material paper with gasifying antirust agent and sealing the packaging metal with the paper coated or impregnated with antirust agent. At present, the commonly used antirust agent that stops repeated measurement of a certain parameter by gasification is ethylamine sulfite

(10) evaporated paper. Evaporated paper, also known as "metal evaporated paper", is a kind of processing paper that carries out metal vacuum coating on the surface of paper. This kind of wrapping paper has the decorative effect of metallic luster. It is cheaper than aluminum/paper laminated materials, but its barrier performance is also similar

(11) aluminum powder processing paper. This is a kind of processing paper made by evenly mixing aluminum powder with casein, kraft glue or other adhesives, and then coating it on the surface of raw paper. This kind of paper has the shiny luster of aluminum powder. Although it does not have the isolation of aluminum foil, it has a beautiful surface and is a popular packaging and decoration material

3. Processing paperboard

the above processing paper is the processing paper with tissue paper as the raw material, which is mainly used as the packaging material for individual packaging such as paper bags. In addition, it can also be bonded with various kinds of facing paper, plastic film, processing paper or metal foil on the paperboard to make various new processing paperboards. For example, resin film can be bonded on the surface of the paperboard to improve the packaging function of the paperboard

IV. cushioning packaging paper

paper can also be used to make cushioning packaging materials. There are mainly several kinds of buffer paper:

1. Shaped cellophane

this is a kind of cellophane with deep grooves, which is used for buffer packaging of biscuits, chocolates, etc

2. Pulp molded container

pulp molded container is a liner material made of pulp directly through molding machine and drying. For example, molded egg trays and fruit trays can greatly reduce the damage rate in transportation

3. Low density paper

as mentioned above, paper is made with ordinary water as the medium, so it is difficult to get low-density paper. However, if you use the papermaking method without water (a kind of non-woven cloth) or the method of special treatment after making with water, you can get low-density paper with a density of only about 0.03. This kind of paper can be used directly or after rolling grooves. It is mainly used as a buffer packaging material for lighter goods

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