Medical packaging paper is a part of medical packaging materials and is used to package medical supplies or medical devices.

Due to the progress of polymer materials, plastic packaging materials have always occupied a dominant position in medical packaging materials. In recent years, with the continuous improvement of environmental protection requirements sfor packaging materials, degradable packaging materials have received more and more attention. At present, medical packaging material products are diversified. The demand for medical packaging paper is constantly increasing, and the requirements are becoming more diverse and refined. In addition to the traditional fluorescent whitening agents that cannot contain large toxic and side effects, there are further requirements in terms of water resistance, antibacterial and antibacterial, and impermeability. Since most of the packaging materials require a printing process, the requirements for the printing surface strength, gloss, and smoothness of paper are also increasing day by day.

As a part of medical packaging materials, medical packaging paper must first meet the requirements of "medical use", that is, it must meet the needs of hygiene and safety; secondly, it must meet the requirements of "packaging materials". That is to meet the printing adaptability requirements of wrapping paper.

Health and safety requirements

1. No fluorescence

The most basic requirement for medical packaging paper is that it must be non-fluorescent paper made of all wood pulp, because the radiation produced by fluorescence is not good for the product and harmful to the human body, and it will produce fluorescence under the light of the sterilization room. The standard stipulates that base paper manufacturers shall not add fluorescent whitening agents that are harmful to the human body during the production process. However, due to the improvement of the pulping process (for example, the bleaching process of some pulp mills first changed from the original "chlorine bleaching" to "semi-chlorine bleaching", it will gradually develop to "full chlorine-free" bleaching to meet the needs of international environmental protection. ). For this reason, some high-grade pulps that use "oxygen bleaching" will also show fluorescent effects under ultraviolet light because they contain some unsaturated double bonds. However this class exhibits "fluorescent fibers" that are not truly fluorescent. It is harmless to the human body. EN868 stipulates every 0.01m. There are no more than 5 fluorescent spots larger than 1mm.

2. Bacteria cannot exceed the standard

After testing by the Product Quality Supervision and Inspection Institute, the total arsenic, lead, and total bacterial colonies of medical packaging paper must meet industry standards or user requirements, and provide users with bacterial inspection reports when necessary.

3. Meet the antibacterial requirements

Whether the medical packaging paper inhibits bacteria is reflected in two aspects. One is the antibacterial test, also known as the agar contact challenge test. It detects whether the Bacillus subtilis can penetrate the medical packaging paper to indicate whether the product can block bacteria. The relevant authoritative testing organization provides the test report on the resistance to bacteria, which is generally submitted for inspection once in a batch or once a year when the process conditions are basically stable. Although this method is accurate, it lags behind and cannot reflect the antibacterial properties of the product in time. Another method is to control the pore size of the medical packaging paper. EN868 stipulates that the average pore size is not greater than 351xm, and the maximum value is not greater than 50txmt. This is because medical packaging must go through a sterilization process. At present, ethylene oxide is used for sterilization, and ethylene oxide sterilization requires air permeability. During use, medical packaging paper must not only meet the sterilization requirements of air permeability, but also prevent the invasion of bacteria. The minimum value of the average larvae diameter is set to ensure air permeability, and the maximum value of the aperture is set to control the invasion of bacteria, which can play a real role in realizing the protection of the product after sterilization.

4. Impermeable to pigments and toxic substances, the content of chloride and sulfate meets the requirements of EN868

According to EN868 regulations. The chloride content shall not be greater than 0.05% (calculated as sodium chloride. Measured according to GB/T2678.5-1996), the sulfate content shall not be greater than 0.25% (calculated as sulfate, determined according to GB/T2678.6-1996 Determination.

Printing requirements

1. Printing surface strength
If the printing surface is not strong enough, it will cause hair loss and powder loss. Hair loss and powder loss not only pollute the pattern, affect product quality, and produce defective products, but also increase the burden of cleaning the printing roller (plate), which brings losses to the printing factory.

2. Printing off powder

Printing powder, also known as printing "white dots". Since medical packaging paper is non-fluorescent paper made of all wood pulp, no filler is used in the production process, so there is no phenomenon of filler powder dropping during the printing process. There are basically three reasons for this printing problem. One is the paper powder produced during the paper roll slitting and sheet cutting process; the other is the ink residue produced by the ink; the third is the dust from the external environment. Generally, the former two are the majority. After a problem occurs, correct identification is the key to solving and preventing it. It is a more accurate method to collect debris from the printing roller for laboratory chemical analysis and microscopic observation, but it requires certain conditions and time. The easier way is to observe the shape of the white spots with a magnifying glass. Paper powder: in the shape of fiber bundles, sometimes in the form of single fibers. Ink residue: typical ring-shaped white spots, the color inside the ring is also darker, the outer ring is arc-shaped, and the inner ring is sharp-angled. The inner ring is more contoured than the outer ring.

3. Printing shedding

Printing lint, also known as napping, is a phenomenon of damage to the paper surface that occurs when the external tensile force applied to the paper surface is greater than the cohesive force of the paper during the production or printing process. Printing lint is mainly caused by insufficient surface strength of the paper. At present, the printing surface strength of medical packaging paper is tested by wax sticks, and the requirement is not less than 8 grades.

4. Printing gloss

Under the premise of satisfying the basic quality conditions, in order to improve the grade of printed matter, the surface gloss must be improved. The surface glossiness mentioned here includes glossiness and smoothness. The printing surface (front side, also called glossy surface) of medical packaging paper has high gloss and smoothness, and the printed pattern is beautiful. Glossiness for medical use: generally requires more than 18% (GB/T8941.1-1988); including smoothness: quantification has an impact on smoothness, and varies according to product quantification. Different degrees of smoothness are required. The general rule is not less than 80s.

Epilogue

At present, the common ones are medical packaging paper for direct printing, medical packaging paper for reverse side glued front printing, and medical packaging paper for reverse side and film composite front printing. Regardless of the use and processing method, the hygienic requirements and printing adaptability requirements of medical packaging paper must be met.

With the continuous development of sterilization methods and the continuous formation of global unified international standards in the medical packaging industry, the requirements for medical packaging paper are also constantly improving and improving. High hygiene safety and good printing adaptability are the development of medical packaging paper. direction.