KR20030012840A - Polymer Composites for ultraviolet ray interception - Google Patents

Abstract

PURPOSE: Provided is a UV-screening resin composition obtained by mixing an inorganic UV-screening agent with a base resin, which can be used for packing materials and containers for UV-screening. CONSTITUTION: The UV-screening resin composition contains inorganic particles(1) having an average particle diameter of less than 500nm, wherein more than 90% of Rutile type titanium dioxide, cerium oxide, or zinc oxide are used as the inorganic particles(1). The inorganic particles(1) can be coated with silicone oil, fatty acid, silicone oxide, or zirconium oxide(2) to prevent the decomposition of polymers by the inorganic particles.

Description

Resin composition for UV protection {Polymer Composites for ultraviolet ray interception}

Many products, such as certain fruit juices, soft drinks, beer, wine, foodstuffs, dairy products, cosmetics, shampoos, vitamins and pharmaceuticals, when packaged in plastic containers that allow light to be transmitted, are adversely affected by UV light, causing them to deteriorate, discolor and decompose. . Ultraviolet rays have shorter wavelengths and higher energy than visible light or infrared rays, and change organic materials. Ultraviolet rays can be classified into the ultraviolet rays A (320-400nm), ultraviolet B (280-320nm), and ultraviolet C (200-280nm) by the wavelength range. The ozone layer is removed by the ozone layer and does not reach the ground surface. The ultraviolet B region is a region capable of causing burns caused by sunlight, and the ultraviolet A region is known to act as a cause of aging and deterioration. Because of their high energy, ultraviolet light can activate many chemicals, altering their structure or paralyzing their function. Therefore, the packaging materials and storage containers are made of resin with added sunscreen, or the packaging materials and surface of the storage containers are treated with sunscreen to block harmful 320 ~ 400nm UV rays so that food, beverages, alcoholic beverages, fruits, daily sundries, It can prevent various destruction phenomena that can be caused by ultraviolet rays such as the inherent taste, color, and aroma of the UV rays of articles such as clothing, and can extend the shelf life, thereby improving the storage and transportation methods. As a result, the price competitiveness of the product can be increased and storage advantages can be obtained. In addition, it can be used as a packaging material for fish or seafood, which should be packaged with foamed polystyrene (Styrofoam), which is difficult to recycle, and can replace aluminum cans that depend only on imports, thereby contributing to cost reduction.

The sunscreen agent has been developed various types of sunscreen agents, which are largely referred to as organic ultraviolet absorbers and inorganic ultraviolet scatterers, and has been performed to reduce the influence of ultraviolet rays by adding them to the resin. Organic ultraviolet absorbers include salicylic acid, benzophenone, cyanoacrylate, etc. having a bonding group capable of absorbing ultraviolet rays in the molecular structure. Recently, there are problems such as lack of heat resistance and weather resistance and stability of the decomposition products. . In order to solve these problems, particulate titanium dioxide or particulate zinc oxide, which is an inorganic ultraviolet scattering agent having an ultraviolet ray blocking effect, has been developed mainly by scattering ultraviolet rays as a metal oxide having a high refractive index, but this also causes problems such as catalytic action. It is becoming. In the present invention, using a titanium dioxide, zinc oxide and zirconium oxide and cerium oxide having a UV blocking function to provide a resin composition having a UV blocking function to increase the stability with the resin, improve dispersibility, catalyst of inorganic sunscreen In order to prevent the deterioration of the resin which may be caused by the activity, the UV-blocking resin composition is made by using an organic-inorganic composite obtained by coating silicon oil, fatty acid salts, and inorganic materials, or inorganic UV-blocking materials that have reduced catalytic activity through physical treatment. For the purpose of providing

1 is a particle (a) coated with a film of silicon oil, a fatty acid salt, a surface treatment inorganic powder in the form of a film on the surface of the ultraviolet protective inorganic powder, and the shape (b) of the particles adhered to the particles.

※ Explanation of code for main part of drawing

1: UV-blocking inorganic powder particles, 2: Surface treatment materials (silicone oil, fatty acid salts, inorganic powder for surface treatment)

2 is a state in which the ultraviolet (organic) inorganic (composite) powder is dispersed in the base resin

1: UV blocking (organic) inorganic (composite) powder, 2: base resin

Hereinafter, the present invention will be described in more detail. As mentioned above, the resin composition for ultraviolet rays blocking of this invention is obtained by mixing an inorganic type sunscreen agent with a base resin in order to block harmful ultraviolet rays.

Resin used in the present invention is, for example, a group of polyethylene (PE), polypropylene (Polypropylene, PP), polyolefin resin and nylon (Nylon). The polyethylene or polypropylene resin is a transparent or translucent solid, has excellent resistance to acids, alkalis, solvents, and has excellent electrical insulation, water resistance, moisture resistance, and cold resistance, so that various containers, wire coatings, pipes, fibers, linings, food containers, Used for hemp, stretching fibers and various packaging films.

Generally used sunscreens can be classified into organic and inorganic based on broadly divided, and organic sunscreens include salicylic acid, benzophenone, cyanoacrylate, etc. Recently, the lack of heat resistance and weather resistance and its decomposition Since the stability of the product and the like is problematic, it is difficult to use. In order to block the ultraviolet ray A region (320-400 nm) which acts as one cause of the deterioration, an inorganic sunscreen was used in the present invention. In the present invention, titanium dioxide, zinc oxide, cerium oxide and zirconium oxide are basically used.

In the case of titanium dioxide, there are four types of amorphous, anatase, rutile, rutile, and brookite. The basic structure of the other three types of crystal structure except the amorphous state is composed of octahedrons formed of six zero atoms and Ti atoms located at the center thereof.The Rutile type shares the octahedron edges, and Anatase octahedrons. Sharing the sides, Brookite is sharing the sides. Anatase transfers to Rutile at 915 ℃ and Brookite transfers to Rutile at 800 ~ 1040 ℃. Rutile is stable in the entire temperature range from room temperature to melting point. Conventionally known techniques for producing UV-blocking resin compositions using titanium dioxide are used without distinguishing between crystalline forms. However, Anatase titanium dioxide has photocatalytic activity, and the photocatalytic effect is detrimental to the base resin and storage contents. In particular, it is pointed out that the generation of single oxygen by photocatalysis causes problems. In order to solve this problem, in the present invention, titanium dioxide having a Rutile content of 98% or more was used to improve the problems caused by the photocatalytic activity of titanium dioxide. In addition, considering that the refractive index is amorphous 2.1, Anatase 2.49, and Rutile 2.70, it can be seen that in the case of Rutile type titanium dioxide, the UV scattering effect is turned on to increase the UV blocking effect. As another method, a titanium dioxide-based composite powder designed in a form capable of reducing catalytic activity by coating hydrophobic silicone oils, fatty acid salts or other inorganic materials was also used.

Zinc oxide, cerium oxide and zirconium oxide can also be used as sunscreens. Like titanium dioxide, hydrophobic silicone oils, fatty acid salts or inorganic materials can be coated to solve the problems caused by catalytic activity (especially cerium oxide). Composite powder forms designed to reduce catalytic activity were also used.

One of the most important matters when preparing a resin composition using the inorganic sunscreen as described above is transparency of films or containers, which are final products obtained from the resin composition. In the case of the secondary packaging shrink film for which the contents do not need to be clearly visible, this opacity is not a big problem, but it can be seen that the primary packaging film and containers used for direct packaging of the product should be transparent from an aesthetic point of view. Especially in the case of films or containers used for packaging fish, juices, vegetables, etc., which are displayed at retail or wholesale stores in bottles or containers, and where consumers first visually determine the freshness and contents of the contents, such a tendency is obvious. Do. From this point of view, the particle size and concentration should be considered very important for the inorganic composite material for UV protection, which is a major factor affecting transparency.

Any suitable process for preparing the resin composition as described in the present invention, such as a master badge manufacturing technique and a compounding manufacturing technique, which is a process for preparing a resin composition known in the art, may be used, and packaging materials and Methods of preparing storage containers also used methods known in the art.

EXAMPLE

Example 1

A resin composition having a UV blocking function was prepared by mixing titanium dioxide having an average particle diameter of 300 nm or less and a rutile type content of 98% or more with a PES resin 1: 9.

Example 2

A cerium oxide surface treated with Silica quality having an average particle diameter of 30 nm was mixed with a PES resin in a 1:99 ratio to prepare a resin composition having a UV blocking function.

Example 3

A resin composition having a UV blocking function was prepared by mixing zirconium oxide having an average particle diameter of 10 nm with a resin in a 5:95 ratio.

By developing packaging materials such as films and containers that have UV blocking function by mixing nano size sunscreen with resin, it can block UVA (320 ~ 400nm) area that changes and alters organic matters with short wavelength and high energy. The present invention provides a resin composition and a method for reducing the catalytic activity of the inorganic material for sunscreen, which is a problem that may occur when using an inorganic UV blocker. Stability was improved.

Claims (7)

Resin composition containing inorganic particles with an average diameter of 500 nm or less for the purpose of blocking UV rays in films or containers made of a polymer material Method of using the inorganic particles uniformly dispersed in the polymer material in the addition of the inorganic particles in claim 1 Method of using the inorganic particles in the coating of the polymer film or the container by mixing the inorganic particles and the coating liquid for the purpose of UV protection in claim 1 Composition of the polymer material using titanium dioxide having a rutile type of 90% or more as an inorganic particle in claim 1 Composition of the polymeric material using cerium oxide particles as inorganic particles in claim 1 Composition using zinc oxide as an inorganic particle in claim 1 Composition of the polymeric material used by coating the surface of the inorganic particle with silicone oil, fatty acid, silicon oxide or zirconium oxide for the purpose of preventing decomposition of the polymeric material by the inorganic particles in claim 1