Cold Formable Blister Laminate for Freeze-Dried Pharmaceutical Products
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional laminates made of plastic-coated aluminum foil for blister packs tend to curl during the freeze-drying process due to temperature changes, which can cause distortion and require identical plastic layers on both sides to prevent curling, limiting their suitability for freeze-dried pharmaceutical products.
Innovation Solution
A laminate structure with different chemical compositions and layer thicknesses for the outer layers, including COC/PE blends, oPP, PET, and PVC, where the aluminum foil is sandwiched between these layers, with specific thicknesses and adhesion methods, allowing for non-identical thermal expansion coefficients, thereby preventing curling during freeze-drying.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If plastic-coated aluminum foil laminate is used for blister packs, then barrier protection against water vapor and gases is improved, but curling and distortion occur during freeze-drying due to temperature changes
Solution Approach 1:
The patent applies different plastic layers with distinct thermal expansion coefficients to different sides of the aluminum foil. The first plastic layer has a first thermal expansion coefficient while the second plastic layer has a second thermal expansion coefficient, creating localized property variations that compensate for curling during freeze-drying while maintaining overall barrier protection.
Solution Approach 2:
The patent creates a composite laminate structure consisting of multiple layers with different materials having different thermal expansion coefficients. This composite structure allows the material to exhibit tailored thermal behavior that prevents curling during temperature changes while maintaining the required barrier properties.
2Stability of the object's composition
If identical plastic layers are arranged on both sides of aluminum foil to prevent curling, then shape stability is improved, but manufacturing flexibility and adaptability are reduced
Solution Approach 1:
The patent allows different plastic layers with different thermal expansion coefficients to be used on different sides of the aluminum foil. This local differentiation maintains shape stability during freeze-drying while enabling greater manufacturing flexibility and adaptability to various pharmaceutical product requirements.
Solution Approach 2:
The patent changes the thermal expansion coefficient parameter by selecting different plastic materials for the two sides. The first plastic layer has a first thermal expansion coefficient and the second plastic layer has a second thermal expansion coefficient, allowing optimization of both stability and flexibility.
3Productivity
If laminate is used for freeze-drying directly in blister base parts, then productivity is improved, but film sections may curl and distort during the process
Solution Approach 1:
The patent employs a composite laminate structure with multiple layers having different thermal expansion coefficients. This composite construction prevents curling and distortion of film sections during freeze-drying, ensuring they remain flat and maintaining productivity.
Solution Approach 2:
The patent utilizes differential thermal expansion of the plastic layers to counteract the curling tendency of the laminate during freeze-drying. By carefully selecting materials with appropriate thermal expansion coefficients, the film sections remain flat throughout the process.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The laminate structure effectively prevents curling and distortion during freeze-drying, ensuring flat film sections and secure sealing, suitable for producing base parts of blister packs for freeze-dried pharmaceutical products without requiring identical thermal expansion coefficients in the plastic layers.
Implementation Method 1
laminates made of plastic-coated aluminum foil tend to curl under the influence of temperature changes during the freeze-drying process
Implementation Method 2
the different chemical composition and/or the different structure of the two outer layers of the laminate is an essential feature of the invention
Data Source
Figure 1~5
AI summary
A cold-workable laminate consists of an aluminium foil (26, 46) whose two sides are coated with a plastic materials and which is used for producing blister bottom parts for blister packaging of pharmaceutical products lyophilised on the bottom. The laminate comprises the following layer sequence: a layer A (22)/ layer B (24)/ aluminium foil 26/, layer C (28)/ and a layer D (30), wherein the layer (A) is embodied in the form of a film consisting of a COC/PE blend or coextruded COC-PE and has the thickness ranging from 10 to 100 µm, the layers B and C are embodied in the form of oPA, oPP or PET foils whose thickness ranges from 10 to 50 µm, the layer D is a foil consisting of the COC/PE blend, coextruded COC-PE or PVC whose thickness ranges from 10 to 100 µm, the layers A and D are different or the layer A (22), layer B (24)/ aluminium foil (26)/, layer C (28)/ and the layer D (30), wherein the layer A is an oPP or PET foil whose thickness ranges from 4 to 20 µm, the layers B and C are the oPP or PET foils whose thickness ranges from 10 to 50 µm and the layer D is embodied in the form of a foil of a COC/PE blend or coextruded COC-PE whose thickness ranges from 10 to 100 µm, or the layer B (44)/ aluminium foil (426)/, layer C (48)/ and the layer D (50), wherein the layers B and C are the oPP or PET foils whose thickness ranges from 10 to 50 µm and the layer D is embodied in the form of an PE coating whose grammage ranges from 8 to 40 g/m2 or the layer B (44)/ aluminium foil (46)/, layer C (48)/ and the layer D (50), wherein the layers B and C are the oPP or PET whose thickness ranges from 10 to 50 µm and the layer D is embodied in the form of a foil of a COC/PE blend or coextruded COC-PE whose thickness ranges from 10 to 100 µm.