Tackifier-Free Adhesive Composition for Absorbent Article Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing adhesive compositions for disposable absorbent articles are costly due to the high percentage of tackifiers, which are difficult to source and can impart undesirable odors and weaken materials, necessitating a need for improved construction adhesives with better performance and lower cost.
Innovation Solution
An adhesive composition comprising at least 90 wt.% of a copolymer, primarily made of propene and 1-butene monomer units, with minimal crystalline content and no tackifier, offering specific properties like viscosity, enthalpy of fusion, tensile strength, and static peel time, to bond absorbent article components effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If tackifiers are used in adhesive composition, then bonding performance is improved, but cost increases and material weakness occurs
Solution Approach 1:
The patent removes tackifiers from the adhesive composition entirely, using a polyolefin-based adhesive that achieves effective bonding without these harmful additives. The adhesive comprises 85-95 wt% polyolefin and 5-15 wt% polymer additive, eliminating the source of material weakness and odor while maintaining bonding performance.
Solution Approach 2:
The patent changes the chemical composition parameters by using specific polyolefin types (polypropylene, polyethylene, or copolymers thereof) with controlled molecular weight and melting point ranges. This parameter optimization allows the adhesive to achieve effective bonding without requiring tackifiers, thereby eliminating material weakness and odor issues.
2Reliability
If tackifiers are used in adhesive composition, then bonding performance is improved, but cost increases
Solution Approach 1:
The patent eliminates tackifiers from the formulation, using cost-effective polyolefin-based materials that achieve bonding performance without expensive additives. The adhesive comprises 85-95 wt% polyolefin and 5-15 wt% polymer additive, removing the costly tackifier component while maintaining effective bonding.
Solution Approach 2:
The patent employs inexpensive polyolefin materials (polypropylene, polyethylene, or their copolymers) as the primary adhesive component. These readily available, low-cost polymers replace expensive tackifier-containing formulations, achieving effective bonding at lower material cost suitable for disposable absorbent articles.
3Strength
If high viscosity adhesive is used, then bonding strength is improved, but application difficulty increases
Solution Approach 1:
The patent optimizes the viscosity parameter by selecting polyolefins with specific melting points (100-160°C) and molecular weights. The adhesive composition achieves a balanced viscosity that allows easy application while maintaining high bonding strength, controlled through the ratio of polyolefin to polymer additive and the specific polyolefin type used.
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 adhesive composition provides effective bonding without tackifiers, reducing costs and material weaknesses, while maintaining performance properties such as viscosity, tensile strength, and peel time, enhancing the assembly of absorbent articles.
Implementation Method 1
an adhesive composition joining at least two of the assembly of components together
Data Source
Figure 1
AI summary
Described herein is an absorbent article having a longitudinal centerline and a lateral centerline, a front waist region with a front waist edge, a rear waist region with a rear waist edge, a crotch region disposed between the front waist region and the rear waist region, and two spaced apart longitudinal side edges joining the front waist edge to the rear waist edge, wherein the absorbent article comprises an assembly of components, and wherein the absorbent article comprises an adhesive composition. The adhesive composition comprises a copolymer; the adhesive composition has a viscosity of from about 2,000 mPa-s to about 11,500 mPa-s at 150 °C, the adhesive composition has a Storage Modulus at 37 °C of from about 3 MPa to 9.5 MPa, and the adhesive composition has a Yield Stress at 37 °C of from about 0.8 MPa to about 1.45 MPa.