JPH05306348A - Reflection-preventing molded product and its production - Google Patents

Abstract

PURPOSE:To provide the reflection-preventing molded product excellent in the durability, while maintaining its good reflection-preventing function, and to provide the method for producing the molded product in simple processes and with an inexpensive installation. CONSTITUTION:The reflection-preventing molded product is characterized by forming a layer comprising a metal compound containing a metal element in the third to fifth periods in the periodic table of the elements on the surface of a polyester molded product having acid groups in an amount of 0.03-0.2mummol/cm<2>. The reflection-preventing molded product is produced by irradiating the surface of a polyester molded product with UV light having wavelengths of <=300nm in an amount of 500mJ/cm<2>, coating the surface with the solution of a metal compound containing the metal element of the third to fifth period in the elementary periodic table to form a mono- to multi-layered thin coating film and subsequently bringing the thin coating film into contact with a fluid heated at >=500 deg.C for a short time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molded article having excellent antireflection performance and a method for producing the same. The antireflection molded product of the present invention can be used in various display devices such as CRTs and LCDs.

[0002]

2. Description of the Related Art Polyester molded products such as polyethylene terephthalate molded products have a large optical refractive index.
The reflection of light is large. For this reason, for the purpose of preventing glare caused by reflection of external light on the surface of the molded product and reflection of a reflected image, an antireflection molded product such as a so-called non-glare sheet having an antireflection film formed on the surface. Is widely used.

[0003] This molded product can form a thin film having a lower refractive index than that of the molded product by applying light interference to the surface.
Alternatively, it can be obtained by alternately forming high refractive index and low refractive index thin films. A metal compound is used as the thin film forming material in order to increase the amount of transmitted light of the molded product. Therefore, the vacuum deposition method has been proposed as a thin film forming method.

[0004]

However, since the metal compound is an organic molded product, the adhesion is poor, and there is a limit to the high temperature heating for enhancing the adhesion, which leaves a problem in the durability of the deposited film. ing. Moreover, since the vacuum deposition method is an operation in a high vacuum, the productivity is relatively low and the equipment is large. Therefore, there are problems such as high manufacturing cost.

An object of the present invention is to provide an antireflection molded article having excellent durability while maintaining a good antireflection function, and to manufacture such a molded article by a simple process and inexpensive equipment. It is to provide a possible method.

[0006]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the inventors of the present invention radiated a specific ultraviolet ray to generate an acidic group in the surface layer, and a metal group was generated in this portion. The present invention has been completed based on the finding that it is very effective to attach a compound and then contact it with a hot fluid for a short time.

That is, according to the present invention, the surface layer portion has 0.03 to 0.2.
Provided is an antireflection molded article in which a layer made of a metal compound of the third to fifth periods in the periodic table of elements is formed on the surface of a polyester molded article having an acidic group of μmol / cm ² . In addition, the present invention, the surface of the molded polyester, 3
By irradiating with ultraviolet rays having a wavelength of 00 nm or less at 500 mJ / cm ² or more, a solution containing a metal compound containing a metal element of the third to fifth periods in the periodic table of elements is attached to the surface to a single layer or another layer. Provided is a method for producing an antireflection molded article, which comprises forming a thin film and then bringing the thin film surface into contact with a high heat fluid of 500 ° C. or higher for a short time.

In the present invention, the "molded product" means a product having a constant shape.

[0009]

The present invention will be described in detail below.

In the present invention, as the polyester,
Examples thereof include homopolymers or copolymers of polyethylene terephthalate, polybutylene terephthalate, polyethylene isophthalate and the like, and the molded products thereof include, for example, film-shaped products, plate-shaped products and other molded products.

A polyester molded product having an acid group of 0.03 to 0.2 μmol / cm ^{2 in} the surface layer is obtained by irradiating the surface of the polyester molded product with ultraviolet rays having a wavelength of 300 nm or less. This ultraviolet irradiation may be carried out by appropriately selecting a wavelength range and irradiation time capable of imparting energy enough to break a part of the ester bond of polyester, and the treatment conditions are the degree of polymerization of polyester and It can be appropriately changed depending on the degree of molecular orientation.

Therefore, although it cannot be specified unconditionally, about 4 eV
The ultraviolet region that gives the above energy is desirable. This UV region must have a wavelength below 300 nm, 1
More preferably, it comprises a wavelength of 80-260 nm. As the light source, a high-pressure mercury lamp that emits light containing ultraviolet rays having a wavelength of 300 nm or less, a low-pressure mercury lamp that mainly emits ultraviolet rays having a wavelength of 300 nm or less, and a deuterium lamp are used. Also,
The irradiation atmosphere may be in air or in vacuum, but irradiation in air is easy in operation and is advantageous in terms of equipment.

Regarding the irradiation amount, it is necessary that the total irradiation amount of ultraviolet rays of 300 nm or less is 500 mJ / cm ² or more. By irradiating at least 500 mJ / cm ² , 0.03 to 0.2 μmol / cm ² of acidic groups are formed on the surface of the irradiated part of the molded product.

When the irradiation dose is less than 500 mJ / cm ² ,
It is difficult to secure the required production amount of acidic groups. The upper limit of the irradiation dose cannot be specified unconditionally because it depends on the wavelength characteristics of the light source, but from the economical point of view it is about
It is about 20000 mJ / cm ² .

In the present invention, the value of the content of acidic groups is
It was expressed as the number of moles (μmol / cm ² ) of the basic dye that can be adsorbed per unit area of the surface of the molded product. This value is a value obtained by the following method.

(1) 0.1 normal sodium acetate buffer (pH
Create 4.5). (2) Prepare a solution with a basic dye methyl violet concentration of 1.0 g / liter using the buffer solution of (1). (3) A 50 × 50 (mm ² ) molded article of the present invention is immersed in this solution for 72 hours (temperature: 25 ° C.). (4) Take out the molded product and wash it with water. (5) Wipe off the water content of the molded product after washing with water. (6) The dye is extracted and dissolved by immersing the molded product in an N-dimethylformamide solution. (7) The absorbance of the dye extract is measured using 589 nm light. (8) Separately, a calibration curve of the dye concentration is obtained from the dye solution dissolved in the N-dimethylformamide solution, and the basic dye concentration per unit area of the molded product is calculated.

That is, the content of acidic groups specified in the present invention means the specific adsorption capacity of the surface. Therefore, if the molded product contains a large amount of acidic groups capable of exhibiting such adsorption ability, the distribution, type, etc. of the acidic group content are not particularly limited.

The polyester molded product of the present invention has a high concentration of acidic groups concentrated on its surface. Therefore, it exhibits a function of forming a coordinate bond between the acidic group and the metal compound in the subsequent treatment.

Therefore, the content of acidic groups is 0.03 to 0.2 μm.
The mol / cm ² is preferably 0.04 to 0.15 μmol / cm ² .

The reason why the wavelength of ultraviolet rays is limited to 300 nm or less is that ultraviolet rays having a wavelength exceeding 300 nm are
This is because even if the irradiation is performed at 500 mJ / cm ² or more, the difference in the amount of acidic groups before and after the irradiation of ultraviolet rays in the present invention is too small, and it becomes impractical.

In the polyester molded product thus obtained, an acidic group is produced in the surface layer portion, and the acidic group is mainly composed of a carboxyl group and a hydroxyl group.

Next, this molded product is treated with a metal compound containing a metal element of the third to fifth periods in the periodic table of the elements.

Examples of the metal element include silicon, aluminum, titanium, vanadium, indium, zirconium, tin, zinc, antimony and the like. Examples of the metal compound containing these elements include metal alkoxides, acetylacetone metal salts, naphthenic acid or octylic acid metal soaps, and inorganic chlorides thereof, and these are used alone or as a mixture, for example, the compound is used as a solvent. It can be dissolved in and used.

In the present invention, the solution containing a metal compound is, for example, a mixed solution obtained by adding an alcohol when a metal alkoxide is selected. When the metal alkoxide is a solid, alcohols as a solvent are appropriately selected, and water necessary for hydrolysis of the alcohol solution of the alkoxide and an acid (or ammonia) as a catalyst are added to the alcohol solution to form a solution. Prepare.

As the solvent, methanol, ethanol,
Alcohols such as propanol and butanol, as well as ethylene glycol, xylene, dimethylformamide, dioxane and the like are used.

Examples of the metal alkoxide used in the present invention include, but are not limited to, tetraisopropoxy titanium, tetramethoxy zirconia, and tetraethoxy silane.

As a method for forming a thin film by depositing a solution of a metal compound in the form of a single layer or multiple layers on the surface of a molded article as described above, a dipping and pulling method, a spinner method, a roll coater method, an offset printing method, etc. Can be used.

After the solvent solution of the metal compound is adhered to the surface of the molded product, in order to remove the solvent, it is dried at room temperature or higher to form a metal compound film. When removing the solvent, it is preferable to appropriately select a temperature that does not affect the molded product. In this case, if desired, a solvent solution of a metal compound having a different refractive index is attached to the surface of the molded article,
The step of drying may be repeated to form a multilayer film. Usually, a metal compound film having a single layer to seven layers is formed.

The metal compound film is for applying the interference of light to effectively cancel the reflected light generated at each boundary and reduce the reflection. For example, the literature (Ceramics 16, 1981,
176, Takahashi et al.) Have clarified the relationship between the refractive index and the thickness when a metal compound film is used.

Therefore, the film thickness of the metal compound of the present invention may be determined according to these documents.

The metal compound layer thus formed on the surface of the molded product is then brought into contact with a high-temperature fluid of 500 ° C. or higher for a short time. As a result, the metal compound film can be firmly adhered to the surface of the polyester molded product, and the strength of the adhered film can be significantly improved.

This contact treatment with the high-temperature fluid is extremely important and is one of the features of the present invention. This treatment can be performed by, for example, a method of contacting with a flame such as natural gas, propane gas, or acetylene gas, or a method of directly blowing high-temperature air onto the film-attached surface. The contact time should be set depending on the heat resistance of the polyester molded product and the contact temperature of the high-heat fluid, but in general, it is desirable to set the contact time to the same place once to 5 seconds or less. If the time is longer than this, problems such as deformation of the molded product occur.

According to such a short-time contact treatment with a high-heat fluid, the thermal conductivity of the organic material is smaller than that of the inorganic material, so that only the layer of the metal compound adhering to the surface of the molded article has a high heat treatment effect. The composition of the metal compound film changes due to the influence and high heat, and the denseness of the film is improved, whereby an antireflection molded product having excellent durability can be obtained.

According to the present invention, such a contact treatment is carried out by a method in which the metal compound film adhered to the surface of the molded product is continuously moved, for example, while the metal compound film is in contact with flame. It is now possible to manufacture a large number of large anti-reflection moldings.

[0035]

According to the present invention, a polyester molded article having an antireflection film having excellent durability can be obtained. Further, such a molded product can be implemented with inexpensive equipment by a simple manufacturing process.

[0036]

EXAMPLES The present invention will be further described below with reference to examples.

Example 1 Ultraviolet irradiation with a total irradiation amount of 1500 mJ / cm ² was performed from above a 125 μm thick polyethylene terephthalate film using a low-pressure mercury lamp giving a central wavelength of 254 nm. The amount of acidic groups in the surface layer of the film after irradiation, by the method described above,
As a result of measurement with the basic dye methyl violet, the amount of acidic groups was 0.08 μmol / in the irradiation surface by the low pressure mercury lamp.
It was cm ² . The amount of acidic groups in the film before irradiation was 0.
It was 01 μmol / cm ² , and an increase of 0.07 μmol / cm ² of acidic groups was observed. The refractive index of the surface of the obtained film was 1.65 [measured by an ellipsometer (manufactured by Mizojiri Optical Co., Ltd.)].

Next, the above film is immersed in a solvent solution of tetraethoxysilane to which ethyl alcohol and water are added, and then pulled up to adhere the solution to the surface of the film and dried at a temperature of 80 ° C. for 5 minutes. , 900Å
A first layer film having a thickness of 1 was formed. On top of that, add tetraisopropoxytitanium by the same method as 950Å
It was adhered so as to have a film thickness of. Next, the tetraethoxysilane solution used for the first layer was used to form the third layer to a film thickness of 1500Å.

Next, the obtained film was transported so that the flame forming portion of the ignited natural gas was in direct contact with the thin film forming portion. The temperature at the point where the flame is directly touched is 6
The temperature was 50 ° C, and the transportation speed was 100 m / min. Under these conditions, the film was reciprocated 3 times to perform high heat treatment.

The properties of the film thus obtained and the conventional film are shown in Table 1 below. Table 1 Luminous reflectance (%) Luminous transmittance (%) Film of this example 2.5 97.0 Conventional film ^* 9.0 88.5 ^* 125 μm polyethylene terephthalate (without coating of multilayer film)

From the table, it can be seen that the film of this example has an excellent antireflection function.

Further, the adhesion between the multilayer film and the film is
As a result of measuring by the cross-cut cellophane tape peeling test method, the grade was 5, and the durability was excellent.

The peeling test was carried out by putting 11 cutting lines on the surface multilayer film at intervals of 1 mm in each length and width to make 100 1 mm ² meshes, pressing cellophane tape on them, and peeling them rapidly upward. I went. The determination is as follows. 5th grade: No peeling 4th grade: 1 to 24 peeling 3rd grade: 25 to 49 peeling 2nd grade: 50 to 74 peeling 1st grade: 75 peeling or more

Comparative Example 1 On the same polyethylene terephthalate film surface as that used in Example 1, a glass plate that cuts ultraviolet rays having a wavelength of 300 nm or less and transmits ultraviolet rays having a longer wavelength than that is placed.
Irradiation was performed from above the glass plate at a dose of 2500 mJ / cm ² using a high-pressure mercury lamp with a central wavelength of 365 nm. The amount of acidic groups on the surface layer of the film after irradiation was 0.01 μmol / cm ² as a result of measurement by the above-mentioned method, which was the same as the amount of acidic groups before irradiation.

A multilayer film was formed on the surface of this film in the same manner as in Example 1, and flame treatment was performed.
Similarly, the adhesion between this film and the multilayer film was measured by a cross-cut cellophane tape peeling test, and the result was grade 1, and this product was inferior in durability.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location C23C 14/20 7308-4K // C08L 67:02 8933-4J

Claims (2)

[Claims] 1. A layer formed of a metal compound containing a metal element of the 3rd to 5th periods of the periodic table of elements on the surface of a polyester molded product having an acid group of 0.03 to 0.2 μmol / cm ² in the surface layer portion. Anti-reflective molding that is used. 2. The surface of the molded polyester article is irradiated with ultraviolet rays having a wavelength of 300 nm or less at 500 mJ / cm ² or more, and the surface is made of a metal compound containing a metal element of the third to fifth periods in the periodic table of elements. A method for producing an antireflection molded article, which comprises depositing a solution in a single layer or multiple layers to form a thin film, and then contacting the thin film surface with a high-temperature fluid of 500 ° C or higher for a short time.