Heat-Bent Polarizing Sheet Packaging for Dry-Free Lens Molding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing production process for polarizing lenses requires preliminary drying of heat-bent polarizing sheets to prevent moisture-induced color change during injection molding, complicating the process and affecting efficiency.
Innovation Solution
A package for heat-bent polarizing sheets that maintains a moisture content of 0.35 wt% or less and water vapor of 15 g/m³ or less, using a non-adhesive isolation film and dampproof materials to prevent moisture absorption during storage and transportation, allowing direct injection molding without preliminary drying.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If preliminary drying is performed on heat-bent polarizing sheets to prevent moisture-induced color change during injection molding, then manufacturing precision is improved, but productivity deteriorates due to additional processing time
Solution Approach 1:
The patent applies preliminary action by controlling the moisture content of the heat-bent polarizing sheet before packaging. The moisture content is controlled to be 0.35 wt% or less before the sheet is packaged in a moisture-proof package, preventing moisture absorption during storage and transportation. This preliminary moisture control eliminates the need for preliminary drying before injection molding, thereby improving productivity while maintaining color consistency.
2Ease of manufacture
If heat-bent polarizing sheets are stored in uncontrolled environment, then storage cost is reduced, but manufacturing precision deteriorates due to moisture absorption and color change
Solution Approach 1:
The patent employs a moisture-proof package that creates a controlled microenvironment for the heat-bent polarizing sheet. This disposable packaging solution maintains low moisture content (0.35 wt% or less) during storage and transportation without requiring expensive controlled storage facilities. The package allows the sheet to be stored in ordinary environments while preventing moisture absorption, thus reducing storage costs while maintaining color consistency.
3Manufacturing precision
If protective films are removed before injection molding, then manufacturing precision is improved, but device complexity increases due to additional handling steps
Solution Approach 1:
The patent applies preliminary action by maintaining the protective film on the heat-bent polarizing sheet during storage and transportation in a moisture-proof package. The protective film continues to protect the sheet surface from fouling and foreign substances until just before injection molding. This eliminates the need for separate protective film removal steps, reducing process complexity while maintaining surface quality.
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
Enables efficient production of high-quality injection-molded polarizing lenses by eliminating the need for preliminary drying and protective film removal, maintaining lens quality over extended storage periods.
Implementation Method 1
a package of heat-bent polarizing sheets which maintains an amount of water in the heat-bent polarizing sheet at a predetermined amount or less and prevents the heat-bent polarizing sheet from absorbing moisture
Implementation Method 2
an amount of water vapor in gas inside the package is 15 g/m³[0024]The package maintains the moisture content of the heat-bent polarizing sheet at a predetermined amount or less
Data Source
Figure 1
AI summary
[Object] To provide a package of a heat-bent polarizing sheet that does not require preliminary drying before injection molding nor substantial protective-film removal work even after preservation (storage, transfer, or transportation) and an injection-molded polarizing lens that uses this heat-bent polarizing sheet. [Solution] A package of a heat-bent polarizing sheet for producing an injection-molded polarizing lens and an injection-molded polarizing lens that uses said sheet, in which a laminated polarizing sheet prepared by bonding a transparent plastic sheet onto each of two sides of a polarizing film formed of a uniaxially stretched polyvinyl alcohol resin film with an adhesive layer interposed therebetween is used as an individual laminated polarizing sheet that has an original plate shape for individual lenses, the individual laminated polarizing sheet is heat-bent to form a spherical surface or an aspherical surface under heating to prepare a heat-bent polarizing sheet, the heat-bent polarizing sheet is set onto a mold, and a transparent resin for lenses is injection-molded onto a concave surface of the heat-bent polarizing sheet, in which the heat-bent polarizing sheet is a heat-bent polarizing sheet that is cumulatively packaged by means of a non-adhesive isolation film so as to withstand moisture and then stored or transported and can be used in injection molding without performing preliminary drying as a pretreatment of injection molding and without substantial protective-film removal work.