A PVC / PVDC medicinal composite hard sheet with good impact resistance

Abstract

The utility model discloses a PVC / PVDC medicinal composite hard sheet with good impact resistance, which relates to the technical field of medicinal composite hard sheets. It comprises a PVC substrate, a polyurethane adhesive layer and a PVDC latex layer, wherein a water-based polyurethane adhesive layer capable of increasing toughness is coated on the PVC substrate, and a PVDC latex layer is coated on the polyurethane adhesive layer. The utility model greatly improves the impact resistance of the PVC / PVDC medicinal composite hard sheet by replacing the water-based polyurethane adhesive capable of increasing toughness without changing the structure of the original PVC / PVDC medicinal composite hard sheet, and can effectively improve the shelf life and environmental applicability of the PVC / PVDC medicinal composite hard sheet.

Description

Technical Field

[0001] The utility model relates to the technical field of medicinal composite hard sheets, in particular to a PVC / PVDC medicinal composite hard sheet with good impact resistance. Background Art

[0002] At present, the packaging of products with high added value, such as medicines, high-end foods, and high-end cosmetics, has high requirements for barrier properties, so most of them use PVC / PVDC as packaging materials, because PVDC materials have excellent barrier properties. The high-barrier PVC / PVDC medicinal composite hard sheets on the market are all made of medicinal PVC hard sheets as the base material, which are coated with adhesives and then dried with high-barrier material PVDC emulsion. The main function is to block water vapor and oxygen in the environment, and prevent water vapor and oxygen in the environment from contacting food and medicine, thereby extending the shelf life of food and medicine. PVDC also has the properties of acid resistance, alkali resistance, oil resistance, solvent resistance, and drug resistance; at the same time, it prevents odor and fragrance from penetrating and dissipating, and extends the shelf life of food and medicine; at the same time, it is safe, environmentally friendly, chemically resistant, easy to use for secondary processing, and has good heat sealing and transparency.

[0003] The high barrier property of PVDC is determined by its molecular structure. PVDC has a linear polymer chain structure connected head to tail. The molecular structure is highly symmetrical, which makes the polymer have high crystallinity and strong intermolecular cohesion. It is difficult for oxygen molecules, water molecules and other gas molecules to move in PVDC molecules. It is also because of this that PVDC shows its high barrier property.

[0004] However, due to its high crystallinity, PVDC has another obvious characteristic, which is that it is relatively brittle at both low and high temperatures. Impact and collision can easily cause surface cracking or even breakage. The brittleness of PVDC materials has seriously affected the promotion and use of PVDC materials, and is also a pain point in the industry. Therefore, there is an urgent need for a PVC / PVDC pharmaceutical composite hard sheet with good impact resistance. Utility Model Content

[0005] In view of the problem that existing PVC / PVDC medicinal composite hard sheets become brittle in low and high temperature environments, the utility model aims to provide a PVC / PVDC medicinal composite hard sheet with good impact resistance, which greatly enhances the toughness and makes the medicinal composite hard sheet more impact-resistant, thereby effectively improving the shelf life and environmental applicability of the PVC / PVDC medicinal composite hard sheet.

[0006] In order to achieve the above-mentioned purpose, the utility model is realized through the following technical scheme: a PVC / PVDC medicinal composite hard sheet with good impact resistance, comprising a PVC substrate, a polyurethane adhesive layer and a PVDC latex layer, the PVC substrate is coated with a water-based polyurethane adhesive layer that can be toughened, and the polyurethane adhesive layer is coated with a PVDC latex layer.

[0007] Preferably, the polyurethane adhesive layer is a water-based polyurethane adhesive with a coating dry weight of 3g.

[0008] Preferably, the water-based polyurethane adhesive is an adhesive containing only one oxygen atom.

[0009] Preferably, the coating dry weight of the PVDC latex layer can be adjusted as needed.

[0010] Preferably, the PVDC latex layer is a high barrier coating.

[0011] The utility model has the following beneficial effects:

[0012] The PVC in the utility model is a substrate layer, a water-based polyurethane adhesive capable of increasing toughness is coated on the PVC substrate, and a PVDC high-barrier coating is coated on the polyurethane adhesive layer. Without changing the structure of the original PVC / PVDC medicinal composite hard sheet, by replacing the water-based polyurethane adhesive capable of increasing toughness, the impact resistance of the PVC / PVDC medicinal composite hard sheet is greatly improved, and the shelf life and environmental applicability of the PVC / PVDC medicinal composite hard sheet can be effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The utility model is described in detail below with reference to the accompanying drawings and specific implementation methods;

[0014] Figure 1 It is a structural schematic diagram of the utility model. DETAILED DESCRIPTION

[0015] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with specific implementation methods.

[0016] Reference Figure 1 This specific implementation adopts the following technical scheme: a PVC / PVDC medicinal composite hard sheet with good impact resistance, including a PVC substrate 1, a polyurethane adhesive layer 2 and a PVDC latex layer 3, the PVC substrate 1 is coated with a water-based polyurethane adhesive layer 2 that can be toughened, and the polyurethane adhesive layer 2 is coated with a PVDC latex layer 3.

[0017] It is worth noting that the polyurethane adhesive layer 2 is a water-based polyurethane adhesive with a coating dry weight of 3g.

[0018] It is noteworthy that the water-based polyurethane adhesive is an adhesive containing only one oxygen atom.

[0019] It is worth noting that the coating dry weight of the PVDC latex layer 3 can be adjusted as needed.

[0020] In addition, the PVDC latex layer 3 is a high barrier coating.

[0021] The main difference between the polyurethane adhesive of this specific embodiment and the original polyurethane adhesive is that the original polyurethane adhesive contains two oxygen atoms in the molecule, while the new polyurethane adhesive contains only one oxygen atom in the molecule. With fewer oxygen atoms, the antioxidant ability is stronger, so that the impact resistance of the sheet will be better and the shelf life will be longer.

[0022] In this specific implementation, a water-based polyurethane adhesive capable of toughening is coated on the PVC substrate 1, and a PVDC high barrier coating is coated on the polyurethane adhesive layer. The adhesive is a water-based polyurethane adhesive with a coating dry weight of 3g, and the coating dry weight of the PVDC latex is 180g.

[0023] In this specific implementation, the structure of the original PVC / PVDC medicinal composite hard sheet is not changed. By replacing the water-based polyurethane adhesive that can increase toughness, the impact resistance of the PVC / PVDC medicinal composite hard sheet is greatly improved, and the shelf life and environmental applicability of the PVC / PVDC medicinal composite hard sheet can be effectively improved.

[0024] The above shows and describes the basic principle and main features of the utility model and the advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only for explaining the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection claimed by the utility model is defined by the attached claims and their equivalents.

Claims

1. A PVC / PVDC medicinal composite hard sheet with good impact resistance, characterized in that: The invention comprises a PVC substrate (1), a polyurethane adhesive layer (2) and a PVDC latex layer (3), wherein the PVC substrate (1) is coated with a water-based polyurethane adhesive layer (2) capable of toughening, and the polyurethane adhesive layer (2) is coated with a PVDC latex layer (3).

2. A PVC / PVDC medicinal composite hard sheet with good impact resistance according to claim 1, characterized in that: The polyurethane adhesive layer (2) is a water-based polyurethane adhesive with a coating dry weight of 3g.

3. A PVC / PVDC medicinal composite hard sheet with good impact resistance according to claim 2, characterized in that: The water-based polyurethane adhesive is an adhesive containing only one oxygen atom.

4. The PVC / PVDC medicinal composite hard sheet with good impact resistance according to claim 1, characterized in that: The coating dry weight of the PVDC latex layer (3) can be adjusted as needed.

5. The PVC / PVDC medicinal composite hard sheet with good impact resistance according to claim 1, characterized in that: The PVDC latex layer (3) is a high barrier coating.

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