â—† To prevent warping of the opening of the cover material, use a composition that does not use ONY//heat seal material.
1. Structure of Covering Material (1) Structure Consisting of Aluminum Foil (2) Structure Consisting of Aluminum Foil and Paper (3) Structure Containing Paper (4) Structure of Simple Thin Film In the above structure, (1) (2) (3) Structure Stiffness is good, (1) (2) especially (2) has strong bendability, and the cover material is opened halfway, and the aluminum foil can be maintained in its original state due to the anamorphism. However, (4) is only a thin film and its stiffness is different.
2. Cover material consisting of a thin film The cover material consisting of a simple thin film is simply a structure in which a hot-melt resin is applied to a light film. However, different contents require dual structures such as barrier properties and pinhole resistance. The cause of warpage of the cover material:
(1) Bimetallic effect of composite products When more than two kinds of biaxially stretched film materials are compounded, the warping effects like bimetals sometimes occur due to different conditions and temperature and humidity during composite processing. Of course, if the stiffness after compounding is strong, the stiffness strength outweighs the warpage, and it will not warp. To prevent this bimetallic effect, the bimetal effect of composite film substrates can be reduced if they are formed using PET//PET or ONY//ONY.
(2) The substrate stretching effect due to temperature and humidity OPP, PET, and ONY will be elongated and shortened due to the influence of temperature and humidity. In particular, the ONY telescope is large. ONY is elongated by the influence of humidity.
The cover material will warp after absorbing moisture. In particular, the surface layer is made of ONY, or a simple structure such as an ONY//heat-sealable material, which causes significant warpage. To prevent this kind of warping, consider the following options.
1ONY//ONY// Heat seal material: Use ONY with different shrinkage rates to balance the warpage.
2OSM / / ONY / / heat sealing material composition.
3PET//Heat seal material: but poor pinhole resistance.
4PET//ONY// heat seal material: but the cost increases.
12 No warping and the tightness of the cover after the boiling treatment is good. 34 No warpage, but there is a problem with the tightness of the cover after boiling.
â—†Why is the ONY//ONY structure of the ONY//ONY structure of the lid member in the structure of the ONY printing film and/or the heat seal layer and/or the heat seal layer structure, the seal strength of the ink portion is poor, and the peeling occurs at the time of peeling. To improve the heat seal strength, ONY printed film // ONY // heat seal layer is used.
The ONY//ONY composition uses ONY materials with different shrinkage dynamics to maintain the vertical and horizontal balance of the shrinkage direction. (The ONY film has a variety of longitudinal shrinkage or lateral shrinkage.)
1. Classification of Cover Materials The structure of cover materials is roughly classified as follows:
(1) Paper-containing composition (2) Composition of aluminum-containing foil (3) Composition of simple film Among them, (1) and (2) have a good structure, and a large vessel such as instant noodle bowl can be stretched Tight and beautiful appearance. In contrast to this, it is only the composition of the thin film. If the substrate is set thinner, there is no stiffness. Even if the lid is compounded with the lidstock, the surface of the lid will loosen and it will look ugly. To solve this problem, you can use ONY.
2. Shrinkage of cover material (1) The biaxially stretched film used for the surface layer of the cover material includes OPP, PET, ONY, and OSM.
The food is loaded into the vessel, sealed, boiled, cooked, etc., and the lid tightly closed. However, MD (longitudinal) and TD (lateral) shrinkage are about the same (if the shrinkage is not balanced, it will not be flat), and shrinkage should be appropriate. (Shrinkage is too large, the vessel will be deformed. If it is too small, it cannot be tightened.) Thus, ONY and OSM materials are more suitable for TD, MD balance and shrinkage.
(2) The ONY shrinkage rate ONY shrinks more than the dry state when processed in a warm water state such as a boiling or steaming process.
Ordinary substrates are relatively balanced compared to other OPP and PET films, but there are differences between MD and TD. For some uses (the shape of the vessel and the sterilization treatment conditions), the shrinkage rate may be excessive. When lower shrinkage is required, a low shrinkage ONY substrate can be used. (Luo Xiaoming) ("China Packaging Newspaper and Print Weekly")
1. Structure of Covering Material (1) Structure Consisting of Aluminum Foil (2) Structure Consisting of Aluminum Foil and Paper (3) Structure Containing Paper (4) Structure of Simple Thin Film In the above structure, (1) (2) (3) Structure Stiffness is good, (1) (2) especially (2) has strong bendability, and the cover material is opened halfway, and the aluminum foil can be maintained in its original state due to the anamorphism. However, (4) is only a thin film and its stiffness is different.
2. Cover material consisting of a thin film The cover material consisting of a simple thin film is simply a structure in which a hot-melt resin is applied to a light film. However, different contents require dual structures such as barrier properties and pinhole resistance. The cause of warpage of the cover material:
(1) Bimetallic effect of composite products When more than two kinds of biaxially stretched film materials are compounded, the warping effects like bimetals sometimes occur due to different conditions and temperature and humidity during composite processing. Of course, if the stiffness after compounding is strong, the stiffness strength outweighs the warpage, and it will not warp. To prevent this bimetallic effect, the bimetal effect of composite film substrates can be reduced if they are formed using PET//PET or ONY//ONY.
(2) The substrate stretching effect due to temperature and humidity OPP, PET, and ONY will be elongated and shortened due to the influence of temperature and humidity. In particular, the ONY telescope is large. ONY is elongated by the influence of humidity.
The cover material will warp after absorbing moisture. In particular, the surface layer is made of ONY, or a simple structure such as an ONY//heat-sealable material, which causes significant warpage. To prevent this kind of warping, consider the following options.
1ONY//ONY// Heat seal material: Use ONY with different shrinkage rates to balance the warpage.
2OSM / / ONY / / heat sealing material composition.
3PET//Heat seal material: but poor pinhole resistance.
4PET//ONY// heat seal material: but the cost increases.
12 No warping and the tightness of the cover after the boiling treatment is good. 34 No warpage, but there is a problem with the tightness of the cover after boiling.
â—†Why is the ONY//ONY structure of the ONY//ONY structure of the lid member in the structure of the ONY printing film and/or the heat seal layer and/or the heat seal layer structure, the seal strength of the ink portion is poor, and the peeling occurs at the time of peeling. To improve the heat seal strength, ONY printed film // ONY // heat seal layer is used.
The ONY//ONY composition uses ONY materials with different shrinkage dynamics to maintain the vertical and horizontal balance of the shrinkage direction. (The ONY film has a variety of longitudinal shrinkage or lateral shrinkage.)
1. Classification of Cover Materials The structure of cover materials is roughly classified as follows:
(1) Paper-containing composition (2) Composition of aluminum-containing foil (3) Composition of simple film Among them, (1) and (2) have a good structure, and a large vessel such as instant noodle bowl can be stretched Tight and beautiful appearance. In contrast to this, it is only the composition of the thin film. If the substrate is set thinner, there is no stiffness. Even if the lid is compounded with the lidstock, the surface of the lid will loosen and it will look ugly. To solve this problem, you can use ONY.
2. Shrinkage of cover material (1) The biaxially stretched film used for the surface layer of the cover material includes OPP, PET, ONY, and OSM.
The food is loaded into the vessel, sealed, boiled, cooked, etc., and the lid tightly closed. However, MD (longitudinal) and TD (lateral) shrinkage are about the same (if the shrinkage is not balanced, it will not be flat), and shrinkage should be appropriate. (Shrinkage is too large, the vessel will be deformed. If it is too small, it cannot be tightened.) Thus, ONY and OSM materials are more suitable for TD, MD balance and shrinkage.
(2) The ONY shrinkage rate ONY shrinks more than the dry state when processed in a warm water state such as a boiling or steaming process.
Ordinary substrates are relatively balanced compared to other OPP and PET films, but there are differences between MD and TD. For some uses (the shape of the vessel and the sterilization treatment conditions), the shrinkage rate may be excessive. When lower shrinkage is required, a low shrinkage ONY substrate can be used. (Luo Xiaoming) ("China Packaging Newspaper and Print Weekly")