Cosmetic Packaging Materials and Compatibility Testing Research

With the rapid improvement of people’s living standards, China’s cosmetics industry is booming. Nowadays, the group of “ingredient party” continues to expand, the ingredients of cosmetics are becoming more transparent, and their safety has become the focus of consumers’ attention. In addition to the safety of cosmetic ingredients themselves, packaging materials are closely related to the quality of cosmetics. While cosmetic packaging plays a decorative role, its more important purpose is to protect cosmetics from physical, chemical, microbial and other hazards. Choose appropriate packaging The quality of cosmetics can be guaranteed. However, the safety of the packaging material itself and its compatibility with cosmetics should also stand the test. At present, there are few testing standards and relevant regulations for packaging materials in the cosmetic field. For the detection of toxic and harmful substances in cosmetic packaging materials, the main reference is to the relevant regulations in the field of food and medicine. On the basis of summarizing the classification of commonly used packaging materials for cosmetics, this paper analyzes the possible unsafe ingredients in packaging materials, and the compatibility testing of packaging materials when they come into contact with cosmetics, which provides certain guidance for the selection and safety testing of cosmetic packaging materials. refer to. At present, in the field of cosmetic packaging materials and their testing, some heavy metals and toxic and harmful additives are mainly tested. In the compatibility testing of packaging materials and cosmetics, the migration of toxic and harmful substances to the contents of cosmetics is mainly considered.

1. Types of commonly used packaging materials for cosmetics

At present, the commonly used packaging materials for cosmetics include glass, plastic, metal, ceramic and so on. The choice of cosmetic packaging determines its market and grade to a certain extent. Glass packaging materials are still the best choice for high-end cosmetics due to their dazzling appearance. Plastic packaging materials have increased their share of the packaging material market year by year due to their sturdy and durable characteristics. Airtightness is mainly used for sprays. As a new type of packaging material, ceramic materials are gradually entering the cosmetics packaging material market due to their high safety and ornamental properties.

1.1 Glass

Glass materials belong to a class of amorphous inorganic non-metallic materials, which have high chemical inertness, are not easy to react with cosmetic ingredients, and have high safety. At the same time, they have high barrier properties and are not easy to penetrate. In addition, most of the glass materials are transparent and visually beautiful, and they are almost monopolized in the field of high-end cosmetics and perfumes. The types of glass commonly used in cosmetic packaging are soda lime silicate glass and borosilicate glass. Usually, the shape and design of this type of packaging material are relatively simple. In order to make it colorful, some other materials can be added to make it appear different colors, such as adding Cr2O3 and Fe2O3 to make the glass appear emerald green, adding Cu2O to make it red, and adding CdO to make it appear emerald green. Light yellow, etc. In view of the relatively simple composition of glass packaging materials and no excessive additives, only heavy metal detection is usually carried out in the detection of harmful substances in glass packaging materials. However, no relevant standards have been established for the detection of heavy metals in glass packaging materials for cosmetics, but lead, cadmium, arsenic, antimony, etc. are limited in the standards for pharmaceutical glass packaging materials, which provides a reference for the detection of cosmetic packaging materials. In general, glass packaging materials are relatively safe, but their application also has some problems, such as high energy consumption in the production process and high transportation costs. In addition, from the perspective of the glass packaging material itself, it is very sensitive to low temperature. When the cosmetic is transported from a high temperature area to a low temperature area, the glass packaging material is prone to freezing cracks and other problems.

1.2 Plastic

As another commonly used cosmetic packaging material, plastic has the characteristics of chemical resistance, light weight, firmness and easy coloring. Compared with glass packaging materials, the design of plastic packaging materials is more diverse, and different styles can be designed according to different application scenarios. Plastics used as cosmetic packaging materials on the market mainly include polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), styrene-acrylonitrile polymer (AS), polyparaphenylene Ethylene glycol dicarboxylate-1,4-cyclohexanedimethanol (PETG), acrylic, acrylonitrile-butadiene[1]styrene terpolymer (ABS), etc., among which PE, PP, PET , AS, PETG can be in direct contact with cosmetic contents. The acrylic known as plexiglass has high permeability and beautiful appearance, but it cannot directly contact the contents. It needs to be equipped with a liner to block it, and care should be taken to prevent the contents from entering between the liner and the acrylic bottle when filling. Cracking occurs. ABS is an engineering plastic and cannot be directly contacted with cosmetics.

Although plastic packaging materials have been widely used, in order to improve the plasticity and durability of plastics during processing, some additives that are not friendly to human health are usually used, such as plasticizers, antioxidants, stabilizers, etc. Although there are certain considerations for the safety of cosmetic plastic packaging materials at home and abroad, relevant evaluation methods and methods have not been clearly proposed. The European Union and the United States Food and Drug Administration (FDA) regulations also rarely involve the inspection of cosmetic packaging materials. standard. Therefore, for the detection of toxic and harmful substances in cosmetic packaging materials, we can learn from relevant regulations in the field of food and medicine. Commonly used phthalate plasticizers are prone to migration in cosmetics with high oil content or high solvent content, and have liver toxicity, kidney toxicity, carcinogenicity, teratogenicity and reproductive toxicity. my country has clearly stipulated the migration of such plasticizers in the food field. According to GB30604.30-2016 “Determination of Phthalates in Food Contact Materials and Products and Determination of Migration” The migration of diallyl formate should be lower than 0.01mg/kg, and the migration of other phthalic acid plasticizers should be lower than 0.1mg/kg. Butylated hydroxyanisole is a class 2B carcinogen announced by the World Health Organization’s International Agency for Research on Cancer as an antioxidant in the processing of commonly used plastics. The World Health Organization has announced that its daily intake limit is 500μg/kg. my country stipulates in GB31604.30-2016 that the migration of tert-butyl hydroxyanisole in plastic packaging should be less than 30mg/kg. In addition, the EU also has corresponding requirements for the migration of light blocking agent benzophenone (BP), which should be lower than 0.6 mg/kg, and the migration of hydroxytoluene (BHT) antioxidants should be lower than 3 mg/kg. In addition to the above-mentioned additives used in the production of plastic packaging materials that may cause safety hazards when they come into contact with cosmetics, some residual monomers, oligomers and solvents may also cause hazards, such as terephthalic acid, styrene, chlorine Ethylene, epoxy resin, terephthalate oligomer, acetone, benzene, toluene, ethylbenzene, etc. The EU stipulates that the maximum migration amount of terephthalic acid, isophthalic acid and their derivatives should be limited to 5~7.5mg/kg, and my country has also made the same regulations. For residual solvents, the state has clearly stipulated in the field of pharmaceutical packaging materials, that is, the total amount of solvent residues shall not exceed 5.0mg/m2, and neither benzene nor benzene-based solvents shall be detected.

1.3 Metal

At present, the materials of metal packaging materials are mainly aluminum and iron, and there are fewer and fewer pure metal containers. Metal packaging materials occupy almost the entire field of spray cosmetics due to the advantages of good sealing, good barrier properties, high temperature resistance, easy recycling, pressurization, and the ability to add boosters. The addition of the booster can make the sprayed cosmetics more atomized, improve the absorption effect, and have a cool feeling, giving people a feeling of soothing and revitalizing the skin, which is not achieved by other packaging materials. Compared with plastic packaging materials, metal packaging materials have fewer safety hazards and are relatively safe, but there may also be harmful metal dissolution and corrosion of cosmetics and metal materials.

1.4 Ceramic

Ceramics were born and developed in my country, are famous overseas, and have great ornamental value. Like glass, they belong to inorganic non-metallic materials. They have good chemical stability, are resistant to various chemical substances, and have good hardness and hardness. Heat resistance, not easy to break in extreme cold and heat, is a very potential cosmetic packaging material. The ceramic packaging material itself is extremely safe, but there are also some unsafe factors, such as lead may be introduced during sintering in order to reduce the sintering temperature, and metal pigments that resist high temperature sintering may be introduced in order to improve the aesthetics of the ceramic glaze, such as cadmium sulfide , lead oxide, chromium oxide, manganese nitrate, etc. Under certain conditions, the heavy metals in these pigments may migrate into the cosmetic content, so the detection of heavy metal dissolution in ceramic packaging materials cannot be ignored.

2. Packaging material compatibility testing

Compatibility means that “the interaction of the packaging system with the contents is insufficient to cause unacceptable changes to the contents or the packaging”. Compatibility testing is an effective way to ensure the quality and safety of cosmetics. It is not only related to the safety of consumers, but also to the reputation and development prospects of a company. As an important process in the development of cosmetics, it must be strictly checked. Although testing cannot avoid all safety problems, failure to test may lead to various safety problems. Packaging material compatibility testing cannot be omitted for cosmetic research and development. The compatibility testing of packaging materials can be divided into two directions: the compatibility testing of packaging materials and contents, and the secondary processing of packaging materials and the compatibility testing of contents.

2.1 Compatibility testing of packaging materials and contents

Compatibility testing of packaging materials and contents mainly includes physical compatibility, chemical compatibility and biocompatibility. Among them, the physical compatibility test is relatively simple. It mainly investigates whether the contents and related packaging materials will undergo physical changes when stored under high temperature, low temperature and normal temperature conditions, such as adsorption, infiltration, precipitation, cracks and other abnormal phenomena. Although packaging materials such as ceramics and plastics usually have good tolerance and stability, there are many phenomena such as adsorption and infiltration. Therefore, it is necessary to investigate the physical compatibility of packaging materials and contents. Chemical compatibility mainly examines whether the contents and related packaging materials will undergo chemical changes when stored under high temperature, low temperature and normal temperature conditions, such as whether the contents have abnormal phenomena such as discoloration, odor, pH changes, and delamination. For biocompatibility testing, it is mainly the migration of harmful substances in packaging materials to the contents. From a mechanism analysis, the migration of these toxic and harmful substances is due to the existence of a concentration gradient on the one hand, that is, there is a large concentration gradient at the interface between the packaging material and the cosmetic content; It interacts with the packaging material, and even enters the packaging material and causes harmful substances to be dissolved. Therefore, in the case of long-term contact between packaging materials and cosmetics, toxic and harmful substances in packaging materials are likely to migrate. For the regulation of heavy metals in packaging materials, GB9685-2016 Food Contact Materials and Additives Use Standards for Products specifies the heavy metals lead (1mg/kg), antimony (0.05mg/kg), zinc (20mg/kg) and arsenic (1mg/kg). kg), the detection of cosmetic packaging materials can refer to the regulations in the food field. The detection of heavy metals usually adopts atomic absorption spectrometry, inductively coupled plasma mass spectrometry, atomic fluorescence spectrometry and so on. Usually these plasticizers, antioxidants and other additives have low concentrations, and the detection needs to reach a very low detection or quantification limit (µg/L or mg/L). Proceed with etc. However, not all leaching substances will have a serious impact on cosmetics. As long as the amount of leaching substances complies with relevant national regulations and relevant testing standards and is harmless to users, these leaching substances are normal compatibility.

2.2 Secondary processing of packaging materials and content compatibility testing

The compatibility test of the secondary processing of packaging materials and the contents usually refers to the compatibility of the coloring and printing process of packaging materials with the contents. The coloring process of packaging materials mainly includes anodized aluminum, electroplating, spraying, drawing gold and silver, secondary oxidation, injection molding color, etc. The printing process of packaging materials mainly includes silk screen printing, hot stamping, water transfer printing, thermal transfer printing, offset printing, etc. This type of compatibility test usually refers to smearing the contents on the surface of the packaging material, and then placing the sample under high temperature, low temperature and normal temperature conditions for long-term or short-term compatibility experiments. The test indicators are mainly whether the appearance of the packaging material is cracked, deformed, faded, etc. In addition, because there will be some substances harmful to human health in the ink, the ink to the inner content of the packaging material during the secondary processing. The migration in the material should also be investigated.

3. Summary and Outlook

This paper provides some help for the selection of packaging materials by summarizing the commonly used cosmetic packaging materials and possible unsafe factors. In addition, it provides some reference for the application of packaging materials by summarizing the compatibility testing of cosmetics and packaging materials. However, there are currently few relevant regulations for cosmetic packaging materials, only the current “Cosmetic Safety Technical Specifications” (2015 edition) stipulates that “the packaging materials that directly contact cosmetics shall be safe, shall not have chemical reactions with cosmetics, and shall not migrate or release to the human body. Hazardous and toxic substances”. However, whether it is the detection of harmful substances in the packaging itself or the compatibility testing, it is necessary to ensure the safety of cosmetics. However, in order to ensure the safety of cosmetic packaging, in addition to the need to strengthen supervision by relevant national departments, cosmetics companies should also formulate Corresponding standards to test it, packaging material manufacturers should strictly control the use of toxic and harmful additives in the production process of packaging materials. It is believed that under the continuous research on cosmetic packaging materials by the state and relevant departments, the level of safety testing and compatibility testing of cosmetic packaging materials will continue to improve, and the safety of consumers using makeup will be further guaranteed.