In the beauty and personal care industry, tubes have emerged as a core packaging solution for products such as facial cleansers, serums, lotions, and hand creams. Their popularity stems from three key advantages: portability, excellent sealing performance, and high flexibility in appearance design. The manufacturing process of these tubes is a tightly linked sequence—every step, from material selection to final delivery, directly impacts the end-user experience and the product’s market competitiveness. This process can be divided into four core stages: material selection, forming & processing, surface decoration, and quality inspection.
1. Material Selection: The Foundation for Matching Product Characteristics
The material of a beauty and personal care tube must be carefully selected based on the properties of the product it will contain, such as acidity/alkalinity, volatility, and oil content. Currently, there are three main types of mainstream materials:
1.1 Single-Layer PE Tubes
- Composition: Made entirely from polyethylene (PE) as a single raw material.
- Advantages: Boasts good chemical resistance, effectively withstanding corrosion from most weakly acidic and alkaline beauty products. It also features low raw material costs and simple processing, making it the first choice for affordable products like budget facial cleansers and hand creams.
- Disadvantages: Relatively weak barrier properties, making it unsuitable for products with high volatile ingredients or those requiring long-term storage.
- Processing Technology: Compatible with traditional extrusion molding. A single extruder is used to produce the tube by melting and shaping the PE.
1.2 Multi-Layer Composite Tubes
- Composition: Typically composed of 2 to 5 layers of different materials, with the key advantage lying in the middle EVOH (Ethylene-Vinyl Alcohol Copolymer) barrier layer.
- Advantages: The EVOH layer effectively blocks the penetration of oxygen, moisture, and volatile substances, significantly extending the shelf life of the contained product. This makes it ideal for high-demand products like serums and ampoule lotions that require strict storage conditions.
- Processing Technology: Relies on multi-layer co-extrusion. Multiple extruders simultaneously melt and co-extrude different materials (PE for outer/inner layers, EVOH for the barrier layer, and adhesive layers) into an integrated multi-layer tube. On-line testing equipment monitors the thickness of each layer (usually 20-50μm) to ensure no delamination and reliable barrier performance.
1.3 Aluminum-Plastic Composite Tubes
- Composition: Features aluminum foil as the core barrier layer, with PE or PP (Polypropylene) as the outer and inner layers.
- Advantages: Aluminum foil offers far superior light shielding, oxygen resistance, and water resistance compared to plastic. It completely isolates light and external air, providing excellent protection for light-sensitive products such as whitening serums and retinol-based functional products.
- Processing Technology: Differs from the above two types. First, aluminum foil and plastic films are combined into a flat composite roll via dry lamination. Then, the roll is fed into a tube-forming machine, which shapes it into an open-ended tube through mechanical rolling and heat bonding. Subsequent steps include cutting and sealing.
2. Forming & Processing: The Key to Ensuring Basic Tube Performance
Forming & processing is the core stage that transforms raw materials into tube blanks. It involves three precise steps—forming, cutting, and sealing—to ensure the tube meets size specifications and sealing standards:
2.1 Extrusion/Composite Forming
- Single-Layer PE Tubes: PE pellets are fed into an extruder, melted at a high temperature (approximately 180-220℃), and then extruded through a die of specific caliber to form a continuous tube blank. Strict control of temperature and extrusion speed is essential to avoid defects like air bubbles or uneven wall thickness.
- Multi-Layer Composite Tubes: Multiple extruders process raw materials for the PE outer/inner layers, EVOH barrier layer, and adhesive layers separately. The molten materials of each layer are precisely bonded in a composite die to form an integrated multi-layer tube. On-line testing equipment monitors the thickness of each layer to ensure uniform barrier layer thickness (20-50μm) and reliable barrier performance.
- Aluminum-Plastic Composite Tubes: First, aluminum foil and plastic films are bonded with adhesives to form a flat composite roll. During lamination, composite pressure (approximately 0.3-0.5MPa) and temperature (approximately 60-80℃) are controlled to ensure tight bonding between the aluminum foil and plastic layers. The composite roll is then fed into a tube-forming machine, which produces open-ended tubes through mechanical rolling and heat bonding—ensuring the tube body is round and free of wrinkles or deformation.
2.2 Precision Cutting
The continuous formed tube is cut to a fixed length based on the product’s preset capacity (e.g., 30ml, 50ml, 100ml). Cutting equipment is equipped with high-precision servo motors and blades, enabling a cutting accuracy of ±0.5mm or less. Infrared detection is used to ensure the cut is smooth and burr-free—uneven cuts can lead to liquid leakage in subsequent sealing steps.
2.3 Bottom Sealing
Sealing methods are selected based on material properties, with the core goal of achieving complete sealing and no liquid leakage:
- Single-Layer/Multi-Layer PE Tubes: Heat sealing is adopted. A heating block heats the tube bottom to the PE melting temperature (approximately 120-150℃), and a certain pressure (approximately 0.2-0.3MPa) is applied to melt and bond the bottom. After cooling, a sealed bottom is formed. Heat sealing time must be precisely controlled (usually 1-3 seconds)—excessively long time causes bottom deformation, while insufficient time results in weak sealing.
- Aluminum-Plastic Composite Tubes: Since aluminum foil cannot be bonded to plastic via simple heat sealing, ultrasonic sealing is used. Ultrasonic vibration (typically 20-40kHz) causes rapid friction and heat generation between the aluminum foil and plastic layers at the tube bottom, achieving local melting and bonding. This method delivers higher sealing strength without damaging the aluminum foil’s barrier properties.
3. Surface Decoration: Enhancing Product Aesthetics and Recognition
The “aesthetics” of beauty and personal care products directly influence consumers’ purchasing decisions. Surface decoration not only enhances the tube’s appearance but also conveys the brand’s tone. Common decoration processes include:
3.1 Screen Printing
Suitable for printing simple patterns, text, or brand logos, supporting single-color or multi-color overprinting (up to 6 colors). During printing, ink is transferred to the tube surface through a screen. Special inks compatible with PE/PP materials must be used to ensure strong adhesion and resistance to peeling.
- Advantages: Low cost and fast processing speed, ideal for mass-market products.
- Disadvantages: Low pattern precision, unable to reproduce complex gradients or fine textures.
3.2 Hot Stamping (Gold/Silver)
A heated stamping plate presses metal foils (gold, silver, or colored foils) onto the tube surface, creating shiny metallic patterns or text. Hot stamping significantly elevates the product’s premium feel, making it suitable for mid-to-high-end products like serums and face cream tubes. It can be combined with screen printing to achieve a “color pattern + metallic logo” effect. During processing, stamping temperature (approximately 80-120℃), pressure (approximately 0.1-0.2MPa), and speed must be controlled to prevent foil wrinkling or peeling.
3.3 Lamination
A transparent or matte film (usually PET or PP) is applied to the tube surface. Its main functions are scratch resistance, fingerprint resistance, and protecting screen-printed or hot-stamped patterns from friction damage. Lamination is available in glossy or matte finishes: glossy film enhances the tube’s luster, while matte film creates a understated frosted texture—both can be selected based on the brand’s tone. Some high-end products use “lamination + partial hot stamping” to further enhance visual layering.
4. Quality Inspection: The Final Line of Defense for Qualified Products
Before leaving the factory, tubes undergo multi-dimensional quality inspections. Only products that meet all standards proceed to the subsequent filling stage. Common inspection items include:
4.1 Sealing Test
- Method 1: Fill the tube with water (simulating the contained product), screw on the cap, invert or place it horizontally for 24 hours, and check for liquid leakage.
- Method 2: Use negative pressure testing—place the tube in a negative pressure environment and judge for micro-leaks based on pressure changes.
- Standard: Tubes with poor sealing (which cause product leakage) are rejected.
4.2 Pressure Resistance Test
Simulating consumer squeezing behavior, a certain pressure (usually 0.5-1MPa) is applied to the tube for 30 seconds. The tube is checked for cracks, deformation, or sealed bottom splitting. Tubes failing this test are prone to damage during use, compromising the user experience.
4.3 Adhesion Test
3M tape is applied to screen-printed, hot-stamped, or heat-transferred patterns, then torn off forcefully. The pattern is checked for peeling—patterns with peeling areas exceeding 5% are deemed unqualified, requiring re-adjustment of printing or stamping processes.
4.4 Dimensional Test
Calipers or image measuring instruments are used to inspect key dimensions such as tube length, diameter, and wall thickness. This ensures compliance with design standards and prevents mismatches with subsequent filling equipment due to dimensional deviations.
After the four stages of manufacturing and inspection outlined above, qualified beauty and personal care tubes are finally ready for delivery. They serve as crucial carriers for beauty products, connecting brands with consumers. With the industry’s growing demand for environmental protection and sustainability, new products such as degradable PE tubes and aluminum-foil-free eco-friendly composite tubes have emerged—driving the continuous development of tube manufacturing technology toward environmental friendliness and high performance.
