Polyethylene (PE) is the most widely used plastic globally, valued for its versatility, cost-effectiveness, and adaptable properties. Its features vary by density (e.g., LDPE, HDPE, LLDPE), but core characteristics include:    Core Features:   1. Chemical Resistance      - Highly resistant to acids, bases, solvents, alcohols, and water.      - Ideal for containers holding cleaning agents, fuels, and chemicals.   2. Moisture Barrier      - Excellent water vapor barrier (low permeability), making it perfect for packaging films, bottles, and pipes.   3. Flexibility & Toughness      - LDPE/LLDPE: Highly flexible, impact-resistant (e.g., squeeze bottles, plastic bags).      - HDPE: Rigid yet tough (e.g., milk jugs, cutting boards).   4. Electrical Insulation      - Low electrical conductivity, widely used in wire/cable coatings.   5. Lightweight      - Low density (0.91–0.97 g/cm³), reducing transport costs.   6. Ease of Processing      - Easily molded via injection molding, blow molding, or extruded into films/fibers.   7. Food-Safe & Non-Toxic      - FDA/EC compliant grades available for food packaging and medical devices.   8. Recyclability      - Widely recycled (♳: HDPE, ♴: LDPE).   ---  Variants & Their Unique Traits:  Type  Density  Key Properties  Common Uses    ----------------------------------------------------------    HDPE  High (0.94–0.97 g/cm³)  Rigid, strong, weather-resistant  Pipes, fuel tanks, toys, hard hats     LDPE  Low (0.91–0.93 g/cm³)  Flexible, transparent, easy to seal  Plastic bags, cling film, squeezable bottles     LLDPE  Linear Low  Superior puncture/impact resistance  Stretch wrap, agricultural films, covers     UHMWPE  Ultra-High  Extreme abrasion resistance, low friction  Medical implants, conveyor belts, bulletproof vests    ---  Limitations:   - Low Heat Resistance: Softens at 80–120°C (varies by type).   - UV Degradation: Requires additives (e.g., carbon black) for outdoor use.   - Poor Adhesion: Surface treatments needed for printing/gluing.   - Permeable to Gases: Not ideal for carbonated drinks (often uses PET instead).     ---  Applications:   - Packaging: Bags, films, bottles, containers.   - Construction: Pipes, geomembranes, insulation.   - Consumer Goods: Toys, kitchenware, caps.   - Industrial: Chemical tanks, cutting boards, bearings.   PE’s balance of durability, processability, and recyclability ensures its dominance across industries, though selecting the 

 Key Limitations of AS Plastic: 1. Poor UV Resistance      - Turns yellow or becomes brittle when exposed to sunlight/UV rays.      - Impact: Unsuitable for transparent packaging meant for sun-exposed displays (e.g., storefronts). Requires UV stabilizers or opaque coatings.   2. Low Chemical Resistance to Solvents      - Vulnerable to strong solvents (e.g., acetone, ketones, chlorinated hydrocarbons).      - Impact: May crack or haze when filled with solvent-based cosmetics (e.g., nail polish removers, certain perfumes).   3. Moderate Barrier Properties      - Allows higher oxygen/moisture transmission than PET or PP.      - Impact: Not ideal for oxidation-sensitive formulas (e.g., vitamin C serums, organic oils) unless paired with special liners.   4. Thermal Sensitivity      - Low heat deflection temperature (∼90–100°C).      - Impact: Cannot withstand hot-fill processes or high-temperature sterilization (e.g., autoclaving). May deform in hot climates during transit.   5. Limited Impact Resistance      - More brittle than ABS, PC, or PP. Prone to cracking under sharp impacts.      - Impact: Risky for travel-friendly packaging or dense products (e.g., thick creams in large jars).   6. Scratch Vulnerability      - Softer surface than PMMA or glass. Easily scratched during handling.      - Impact: Loses clarity/gloss over time; affects premium aesthetics.   7. Not Food-Grade Compliant for All Regulations      - Some AS formulations may leach styrene monomers under extreme conditions.      - Impact: Requires strict compliance testing for lip/eye products in regulated markets (e.g., EU, FDA).    When to Avoid AS Plastic in Cosmetics: - Products requiring long-term UV exposure (e.g., sunscreen, window-displayed items).   - Formulas with high solvent content (e.g., nail polish, removers, alcohol-heavy toners >20%).   - Hot-fill processes (e.g., molten waxes, hot-pour formulations).   - Oxygen-sensitive actives (e.g., retinoids, unstable antioxidants).   - High-impact applications (e.g., thick cream jars, compacts prone to dropping).   ---    Alternatives for Demanding Applications: | Limitation          | Better Alternatives        | |---------------------|----------------------------| | UV Resistance       | PMMA (acrylic), UV-stabilized PET | | Chemical Resistance | PP, HDPE, COP/COC           | | Barrier Properties  | PET, EVOH-multilayer, Glass  | | Heat Resistance     | PP, PPSU, Glass    ...

AS Plastics (Acrylonitrile-Styrene) is a widely used thermoplastic material in cosmetic packaging due to its excellent clarity, rigidity, and chemical resistance. Below are its key features and applications in the cosmetic industry:    Features of AS Plastics in Cosmetic Packaging: 1. High Clarity & Gloss      - AS offers glass-like transparency, making it ideal for showcasing cosmetic products (e.g., serum bottles, lip gloss tubes).      - Maintains aesthetic appeal with a premium finish.   2. Good Rigidity & Durability      - Provides structural integrity for bottles, jars, and containers without being overly brittle.      - Resists cracking under stress, ensuring longevity.   3. Chemical Resistance      - Compatible with alcohols, oils, and common cosmetic ingredients, preventing degradation or cloudiness.      - Less prone to stress cracking compared to some other plastics.   4. Lightweight & Cost-Effective      - Lighter than glass, reducing shipping costs.      - More affordable than high-end plastics like PMMA or Tritan while maintaining good performance.   5. Ease of Processing      - Suitable for injection molding, blow molding, and extrusion, allowing for versatile designs (e.g., compact cases, dropper bottles).      - Can be colored or coated for branding purposes.   6. Barrier Properties      - Moderate resistance to moisture and gases, though not as strong as PET or PP. Often used for non-sensitive formulations (e.g., shampoos, lotions).    Applications in Cosmetic Packaging: 1. Bottles & Jars      - Clear or tinted containers for serums, toners, and lotions.      - Pump bottles for hand sanitizers or liquid soaps.   2. Compacts & Makeup Cases      - Rigid casings for pressed powders, blushes, and eyeshadows.     3. Dropper Bottles      - Used for essential oils, facial oils, and high-clarity liquid products.     4. Tubes & Caps      - Squeeze tubes for creams or caps for larger containers.     5. Secondary Packaging      - Transparent outer shells or display boxes for gift sets.      Comparison with Other Plastics: - VS PET: AS is more rigid but has slightly lower chemical resistance.   - VS PP/PE: AS is clearer but less flexible.   - VS PMMA: AS is cheaper but less scratch-resistant.      Limitations:   - Not suitable for highly abrasive or high-temperature applications.   - May require coatings for enhanced UV resistance.     AS plastics strike a balance between cost, clarity, and functionality, making them a popular choice for mid-to-h...

Although ABS plastic has certain applications in cosmetic packaging, its disadvantages are more obvious than other commonly used plastics (such as PP, PET, PE, AS, etc.), which are mainly reflected in the following aspects: 1. Poor chemical resistance Sensitivity to solvents: ABS is easily corroded by certain organic solvents (such as ketones, esters, and some alcohols), causing surface dissolution or cracking. Fragrances, essential oils, or certain active ingredients in cosmetics may react with it, affecting the integrity of the packaging. Long-term stability issues: Long-term contact with oils or acidic ingredients may cause ABS to age or discolor, affecting the appearance of the product. 2. Low transparency Not suitable for transparent packaging: ABS is usually translucent or opaque (unless specially modified), and cosmetic packaging often requires high transparency to display the contents (such as essence, toner). In contrast, materials such as PET, AS or PMMA have higher transparency. 3. Weak weather resistance and UV resistance Easy to yellow and embrittle: ABS is easily oxidized and yellowed under ultraviolet radiation or high temperature environment, affecting the appearance. If cosmetics need to be displayed for a long time or exposed to sunlight (such as sunscreen product packaging), ABS may not be suitable, while PET or PC have better UV resistance. 4. Environmental protection and recycling issues Difficulty in recycling: ABS is an engineering plastic, with complex recycling classification and lower recycling value than general plastics such as PP and PET. With the trend of emphasizing sustainable development, brands may tend to choose materials that are easier to recycle. No bio-based options: ABS is usually petroleum-based plastic, while some cosmetics brands prefer biodegradable materials (such as PLA) or recycled PET (rPET). 5. Cost and processing limitations Price fluctuations: The price of ABS raw materials is greatly affected by the market of monomers such as styrene and may not be as stable as PP or PE. High processing requirements: Temperature and humidity must be strictly controlled during ABS injection molding, otherwise defects (such as silver streaks) are prone to occur. PP has a wider processing adaptability and is suitable for rapid production. 6. Hygiene and safety concerns Residual monomer risk: Styrene monomer (potentially harmful substance) may remain in the ABS synthesis process, and strict testing is required to ensure compliance with the migration standards of cosmetic packaging (such as EU EC 1223/2009). PP, HDPE and other materials are more inert and safer. 7. Limitations of mechanical properties General temperature resistance: The heat resistance temperature of ABS (about 8085°C) is lower than that of PP (can withstand more than 100°C), and it is not suitable for high-temperature filling or sterilization processes. Insufficient wear resistance: The surface of cosmetic packaging often needs to be printed or coat...

ABS plastic (Acrylonitrile Butadiene Styrene copolymer) is widely used in cosmetic packaging due to its excellent comprehensive properties. Below is an analysis of its core applications and characteristics:  I. Primary Applications 1. Bottle Caps and Pump Heads       Its high hardness and dimensional stability make it suitable for threaded caps, press pumps, and other components requiring precise structures.   2. Cream Jars and Makeup Containers       Commonly used for foundation compacts, eyeshadow palettes, and other packaging due to its ease of dyeing and glossy surface, which enhances premium aesthetics.   3. ToolBased Packaging       Components like mascara wands and lipstick tubes benefit from its mechanical strength, ensuring durability with repeated use.   4. Secondary Processing Components       Combined with other materials (e.g., glass or PET bottles) as decorative brackets or functional accessories.    II. Core Properties and Advantages 1. Strong Mechanical Performance       Impact resistance (contributed by butadiene) suits shockproof needs during transport, while hardness (from acrylonitrile) prevents scratches.   2. Versatile Surface Treatment       Can be electroplated, spraypainted, or UVcoated to achieve metallic or matte finishes, elevating the product’s perceived value.   3. Chemical Resistance       Resists alcohols and oils (common in skincare) but should avoid strong solvents (e.g., acetone).   4. Ease of Processing       Highefficiency injection molding allows for complex structures (e.g., multilayer snap designs), reducing production costs.   5. Lightweight and CostEffective       Low density (~1.041.06 g/cm³) makes it lighter than glass, with costs lower than engineering plastics like PC.     III. Limitations and Considerations  Poor Weather Resistance: Prolonged UV exposure may cause yellowing, requiring UV stabilizers or opaque packaging.    Permeability: Unsuitable for highly volatile contents (e.g., perfumes) requiring airtight sealing.    Environmental Pressure: Nonbiodegradable; recycling systems (e.g., chemical recycling) are needed to comply with regulations.    IV. Comparison with Other Materials | Property             | ABS        | PP (Polypropylene) | Glass      | ||||| | Impact Resistance    | ★★★★☆      | ★★★☆☆             | ★☆☆☆☆       | | Surface Decoration   | ★★★★★      | ★★★☆☆             | ★★★★☆       | | Heat Resistance      |...

Since the invention of plastic, there are more than 300 types of plastic. However, no more than 10 types are commonly used in cosmetic plastic packaging: PET, PETG, PE, PP, PMMA, AS, PS, ABS, MS and PCR. The unique chemical and physical properties of each plastic affect its application in cosmetic packaging, resulting in different materials being suitable for each cosmetic packaging product. This also results in different packaging costs for different products. Today, we want to help you choose the best material for your product packaging by giving the characteristics, applications, advantages and disadvantages of these 10 common cosmetic packaging plastics. Plastics Used In Cosmetic Packaging Plastics have the following significant advantages over wood, metal and glass in cosmetic packaging: 1. Lightweight and portability - Lightweight: The density of plastics is much lower than that of glass and metal, which reduces transportation costs and improves user experience (especially for travel packs). - Drop resistance: Not easy to break, better than glass and ceramics, suitable for daily carry. 2. Cost-effectiveness - Raw materials and production: Petroleum-based raw materials are low in cost, and the injection molding/blow molding process is efficient, which is more economical than metal processing or glass blowing. - Transportation savings: Lightweight reduces logistics costs. 3. Design flexibility and functional integration - Various shapes: Can be injection molded into complex shapes (such as pump heads, hoses), with rich transparent/colorful effects (imitation glass texture). - Functional innovation: Easy to match with droppers, air cushions and other components to meet special cosmetic needs (such as vacuum preservation). 4. Durability and safety - Corrosion resistance: Unlike metals, it is not easily oxidized and avoids reactions with cosmetic ingredients (such as acidic products). - Sanitary protection: It can be modified to have antibacterial properties and good sealing properties (such as PET bottles are leak-proof). 5. Environmental adaptability - Mature recycling system: PP, PET, etc. have recycling channels, and biodegradable plastics (such as PLA) are gradually being used. - Reduction design: Thin-wall technology reduces material usage, and the carbon footprint may be lower than glass (full life cycle assessment is required). Shortcomings compared to other materials: - Wood: It is easy to get damp and breed bacteria, and the processing accuracy is low. - Metal: It is heavy and costly, and the thermal conductivity may affect the stability of the product. - Glass: High energy consumption (melting temperature > 1500℃), high risk of breakage. Trends: Sustainable upgrading: The application of bio-based materials such as recycled plastics (r PET) and sugarcane PE is increasing, and the environmental impact is further reduced in combination with light weighting. With the above-mentioned comprehensive advantages, plastic has become the main...

On the fifth day of the fifth lunar month, dragon boats race across the water, and the aroma of zongzi fills the air. As one of China's four major traditional festivals, the Dragon Boat Festival has long been woven into the cultural fabric of the Chinese nation. Amid the lively atmosphere of eating zongzi and watching dragon boat races, have we ever pondered the deeper cultural codes behind this festival? The Dragon Boat Festival is far more than a simple "Poet's Day" or "Zongzi Day"—it is a composite festival carrying multiple layers of cultural memory, its origins revealing a fascinating diversity. From ancient dragon totem worship to commemorating the great poet Qu Yuan, from seasonal customs for warding off epidemics in summer to celebrating loyalty and righteousness, the Dragon Boat Festival is like a prism, refracting the vibrant spectrum of Chinese civilization. The earliest origins of the Dragon Boat Festival can be traced back to summer solstice rituals during the pre-Qin period. Ancient Chinese observed celestial phenomena and noticed that in mid-summer during the fifth lunar month, the Azure Dragon constellation (Canglong Qixiu) ascended to the zenith of the southern sky, as described in the fifth line of the Qian hexagram in the *Book of Changes*: "The flying dragon is in the heavens." This period marked the peak of yang energy, while poisonous insects and diseases began to thrive. The people of the pre-Qin era regarded this day as the "evil month and evil day," forming customs such as bathing in orchid-infused water, hanging mugwort, and wearing fragrant sachets to ward off evil spirits. The *Xia Xiaozheng* records: "On this day, medicine is stored to eliminate toxic vapors," while the *Da Dai Liji* mentions "collecting orchids for bathing." These customs reflect the ancient people's observations of natural cycles and their wisdom in responding to them, forming the earliest cultural layers of the Dragon Boat Festival. As history progressed, the festival became closely intertwined with dragon totem worship. Scholar Wen Yiduo, in his work *Research on the Dragon Boat Festival*, proposed that the festival originated as a dragon totem sacrificial ceremony among the ancient Wu and Yue peoples of the middle and lower Yangtze River regions. With their water-rich environment, these communities revered the dragon as a totem, offering sacrifices through dragon boat racing and throwing zongzi into the water to pray for favorable weather and abundant harvests. Dragon boat races mimicked the form and movements of dragons, while zongzi may have been offerings to water deities. These primitive religious rituals gradually evolved into recreational activities, but their core—reverence for nature and prayers for life—has endured. In regions like the Miluo River in Hunan and Suzhou in Jiangsu, ancient rituals worshiping dragon gods are still preserved today, serving as vivid evidence of this origin theory. During the Warring States period, the cultural...

  Every year on May 1st, bright red flags flutter, and joyful songs fill the air as people enjoy their hard-earned holiday. Known as "Labor Day," this occasion is framed in official narratives as a celebration of the glory of labor and the spirit of dedication. Yet, when we peel back the layers of history, we discover that the true origins of International Workers' Day stand in stark contrast to today’s warm and fuzzy festivities—it was born from the bloody struggles of the working class, etched into the darkest chapters of capitalist development. The essence of this holiday is not an affirmation of the existing order but a call to remember the obscured history of class struggle.   On May 1, 1886, Chicago witnessed an unprecedented wave of worker strikes. More than 350,000 workers took to the streets with a simple and direct demand: an eight-hour workday. "Eight hours for work, eight hours for rest, eight hours for what we will"—a slogan that seems normal today, but back then, it was a right workers had to fight for with their lives. In late 19th-century America, laborers typically worked 14 to 16 hours a day, sometimes even longer, for meager wages that barely sustained survival, all while toiling in perilous conditions. Capital, like a ravenous beast, devoured the sweat and blood of the working class.     What began as a peaceful protest soon turned into a bloodbath. On May 3, clashes broke out between striking workers at the McCormick Harvesting Machine Company and strike-breakers, prompting police to open fire, killing and injuring several. The next day, workers gathered at Haymarket Square to protest. As police moved in to disperse the crowd, a bomb was thrown, killing seven officers and at least four workers—an event later dubbed the "Haymarket Affair" or "Haymarket Massacre." Authorities responded with brutal repression: eight labor leaders were arrested, sentenced to death, and four were ultimately hanged. These activists were branded as "anarchists," their real crime being nothing more than daring to fight for the basic rights of the working class.   This history has been quietly erased from today’s official Labor Day narratives. In the U.S., mainstream society deliberately set Labor Day on the first Monday of September, distancing it from the radical origins of May 1. In socialist countries, while International Workers' Day was retained, its original meaning—as a rebellion against capitalist oppression—was hollowed out into the vapid slogan of "glorifying labor." The class-struggle essence of the holiday was diluted, repurposed as a harmless endorsement of the existing economic order. This politics of memory amounts to a systemic erasure of labor movement history.   To grasp the true significance of International Workers' Day, we must revisit the living conditions of the 19th-century working class. Workers then endured not only grueling hours but also deadly environments. A survey from 1...