Introduction
Following our previous guide on the critical properties tests for flexible packaging, this article comprehensively discusses what instruments are needed for professional modern packaging material testing and quality control processes.
To ensure product safety, regulatory compliance, and supply chain resilience, specialized equipment capable of simulating real-world conditions with high precision is needed. This guide introduces the essential instruments required across three core testing categories: barrier properties, mechanical integrity, and chemical safety.
Section 1: Equipment for Barrier Property Testing
Barrier testing is foundational to package performance, as it determines a material's ability to protect the product inside from external gases and moisture. Labthink is a leading provider of packaging barrier performance testing instruments and services, offering automated, high-precision instruments that meet global standards like ASTM and ISO.
1. Water Vapor Transmission Rate (WVTR)Tester
- What is a WVTR Tester?
A WVTR Tester (or a Permeation Analyzer) is used to precisely measure the rate at which moisture permeates through a film. This rate is critical for determining a product's shelf life.
- What is the Function of a WVTR Tester?
It quantifies the amount of water vapor (g) that passes through a standardized surface area (m^2) over 24 hours (Day), reported as g/m^2/day.
- How does a WVTR Tester work?
Instruments often use sophisticated technologies such as infrared sensors or electrolytic sensors for ultra-high precision, or the classic gravimetric method (weight change) for general-purpose and reference standards.
- Why is the WVTR test important?
This test is essential for packaging dry goods, pharmaceuticals, electronics, and any product sensitive to moisture ingress.
Labthink C306H and C390H Water Vapor Transmission Rate Test System are designed and manufactured based on infrared sensor method and conform to the requirements of ASTM F1249 and ISO15106-2. This instrument can be used to measure the water vapor transmission rate of barrier materials with high and medium moisture barrier properties with a wide testing range and high testing efficiency. C306H and C390H apply to the determination of water vapor permeability of plastic films, sheeting, paper, packages and other related packaging materials in food, pharmaceutical, medical apparatus, consumer goods, photovoltaic and electronic industries, etc.
2. Oxygen Transmission Rate (OTR) Tester
- What is an OTR Tester?
- What is the Function of an OTR Tester?
It quantifies the amount of oxygen (in cm^3) that passes through a film's surface area (m^2) over 24 hours (day), reported as cm^3/m^2/day.
- How does an OTR Tester work?
The most common high-precision method employs the coulometric sensor technique, which provides highly accurate measurements needed for demanding applications.
- Why is the OTR test important?
This is a critical test for packaging sensitive to oxidation, such as many fresh foods, beverages, and pharmaceuticals, where oxygen can cause spoilage, rancidity, and loss of efficacy.
3. Gas Permeability Testers
- What is a Gas Permeability Tester?
This category includes instruments designed to measure and verify the passage of various gases, whether through the material film or across the finished package.
- What is the Function of a Gas Transmission Rate (GTR) Tester?
This equipment confirms the effectiveness of the gas barrier for specific applications beyond oxygen and water vapor. This includes measuring gases like nitrogen or carbon dioxide through the material itself or a sealed package.
- Why is the GTR test important?
CO2 permeability is crucial for carbonated beverages and products where gas retention is required. Conversely, N2 permeability is important for materials used in inert gas flushing or Modified Atmosphere Packaging (MAP), where the inert gas must remain inside the package to prevent degradation.
- Can Hazardous or industrial gases permeability be tested?
While essential for packaging films, these highly accurate gas permeability testers are also utilized in broader industrial contexts. This includes testing materials used in gas filtration, safety membranes, or protective apparel for their effectiveness against the permeation of hazardous or industrial gases
Section 2: Mechanical & Physical Integrity
These instruments assess the material's durability, structural integrity, and ability to handle the rigors of high-speed manufacturing and the global supply chain.
1. Tensile Testing Machine
- What is a Tensile Testing Machine?
A Tensile Testing Machine measures the fundamental strength and deformation characteristics of a material when subjected to a controlled pulling force.
- What does a Tensile Testing Machine do?
It measures fundamental properties such as tensile strength (the maximum stress a material can withstand before breaking), elongation (how much the material stretches), and yield strength (the point at which the material begins to deform permanently).
- Why is tensile strength important for films and packaging materials?
This data is critical for predicting how a film will behave on high-speed form-fill-seal (FFS) machinery, resisting tearing, and enduring stress during handling and transportation.
2. Coefficient of Friction (COF) Tester
- What is a COF Tester?
A COF Tester measures the static and kinetic friction between two surfaces.
- What does a COF Tester do?
It determines the force required to initiate movement (static COF) and the force required to maintain movement (kinetic COF) when one packaging material slides over another(or over machine parts).
- Why is COF test important?
This measurement is crucial for materials used in automated, high-speed lines. Low COF ensures smooth, continuous movement through machinery, while a higher COF may be needed on the exterior of a stackable finished package to prevent slipping.
3. Heat Seal Tester
- What is a Heat Seal Tester?
A Heat Seal Tester is a specialized laboratory instrument used to determine the optimal sealing parameters for a given packaging material.
- What does a Heat Seal Tester do?
It creates controlled seal samples by precisely regulating the three critical variables: temperature, pressure, and dwell time.
- How does a Heat Seal Tester differ from a heat sealer?
Heat Seal Tester is the lab instrument that isolates variables to determine the material's ideal parameters, which are then transferred to the production equipment.
4. Leak and Seal Strength Testers
- What is a Leak and Seal Strength Tester?
These instruments are essential for verifying the integrity of the finished, sealed package, especially for sterile medical devices and sensitive food products.
- How does a Leak and Seal Strength Tester work?
Leak and Seal Strength Testers use either negative pressure (vacuum) or positive pressure (burst) to physically challenge the package. They detect failures, pinholes, and channel defects in the seals.
- What are the advantages of Non-Destructive CCI Testing?
Non-Destructive CCI Testing (Pressure Decay): Container Closure Integrity (CCI) testing using methods like the pressure decay method(regulated by standards like ASTM F2338). The key advantage of the pressure decay method for Container Closure Integrity (CCI) is its ability to detect very small leaks—often down to a few microns—in a sealed package. This high sensitivity is crucial. Since the method is non-destructive, it allows manufacturers to test high-value, often sterile, products (like vials, syringes, and blister packs used in the medical and pharmaceutical industries)without damaging the product itself.
The use of non-destructive CCI testing is strongly recommended, and in some cases, required, by regulatory bodies like the FDA for sterile and stability-critical products. Mentioning the specific standard (ASTM F2338)further solidifies the legitimacy of its application in highly regulated fields.
5. Impact, Tear, and Other Physical Testers
What other widely used equipment measures resistance to various specific physical stresses?
- Impact Tester (Falling Dart/Ball): Measures a material's resistance to puncture or rupture from a sudden, sharp force, simulating accidental drops or impacts.
- Tear Tester (Elmendorf type): Quantifies the force needed to propagate (continue) a tear once it has started. This indicates the material's toughness and helps predict performance when a package is intentionally or accidentally nicked.
- Thickness Tester: A high-precision digital micrometer used to ensure film gauge uniformity. This is vital for consistent barrier properties, mechanical performance, and accurate cost control.
- Rub Tester: Simulates abrasion and rubbing forces encountered during transport to test the durability and adhesion of printed inks, coatings, and labels on a package's surface.
Section 3: Equipment for Chemical Safety& Compliance
This category includes analytical instruments necessary for safety and compliance testing, ensuring food-contact and pharmaceutical-grade materials meet strict global health and regulatory requirements.
Migration Testing
- What is Migration Testing？
Migration and Non-Volatile Matter Testers comprise a suite of analytical equipment designed specifically to test for any chemical leaching from the packaging into the product, or vice versa.
- What does Migration Testing do?
These tests determine if any substances (like monomers, plasticizers, or other non-volatile compounds) migrate out of the packaging material and into a simulated food or drug solvent. This is often done by extracting the compound and then measuring the residue mass (gravimetric analysis).
- Why is Migration Testing Important?
This analysis is mandatory for compliance with strict food and drug safety regulations, such as those set by the FDA and various global regulatory bodies, ensuring the packaging does not contaminate the product and poses no health risk to the consumer.
Summary
The decision to invest in a laboratory is a commitment to product quality, consumer safety, and regulatory certainty. By equipping a lab with precision instruments for Barrier, Mechanical, and Chemical testing, manufacturers can move beyond mere compliance to achieve genuine quality excellence.
Labthink is your comprehensive partner in this endeavor, providing high-precision testing instruments for every category outlined above, ensuring your product meets the rigorous demands of global commerce and manufacturing.