JPH06143339A - Composite resin molded body and manufacture thereof - Google Patents

Abstract

PURPOSE:To improve haze resistance, scratch resistance and productivity. CONSTITUTION:By moving movable retainer plates 14 and 14 and slide cores 13 in an injection mold 10, the injection mold 10 is brought into a closed state. When the injection mold 10 is brought into a closed state, a cavity 20 is partitioned. In the cavity 20, on which thermoplastic transparent cellulose resin layer is formed, molten resin is injected and filled so as to mold a swimming goggle. Further, alkali saponification treatment is applied to the thermoplastic transparent cellulose resin layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite resin molding and a method for producing the same. More specifically, the present invention relates to a composite molded article for preventing sunglasses, lenses for swimming goggles, windows for buildings, etc. from fogging or dew condensation due to changes in environmental temperature and humidity, and a method for producing the same.

[0002]

2. Description of the Related Art Various methods for performing anti-fog processing on transparent resins such as swimming goggles are known. A lens formed of a cellulosic resin or a lens further subjected to alkali saponification has advantages such as no optical problems and excellent antifogging property, but the cellulosic resin is weak in impact resistance. However, it has drawbacks such as poor heat resistance and weak water resistance.

There is a surface hydrolysis treatment with alkali which is one of the chemical treatments. This is a method in which sodium hydroxide and potassium hydroxide are mixed at a certain ratio and a cellulosic plastic base material is dipped in an aqueous solution (Japanese Patent Publication No. Sho 6).
0-32653, JP-B-60-32653).

The high anti-fogging property of this cellulosic plastic is considered to be due to its excellent wettability due to the chemical structure peculiar to cellulose, its deeper processing depth compared to physical processing, and its large effect of absorbing water inside. ing.

Polycarbonate (PC) lenses are
It is excellent in impact resistance, heat resistance, water resistance, etc., but in order to impart anti-fogging property, coating the anti-fogging material on the lens part causes coating thickness error, coating unevenness, traces of liquid flow However, there are drawbacks such as an optical defect caused by a shape error due to mixing of dust and the like, and the coating film may be peeled off.

Also known is a method of coating the surface of a base resin with a hydrophilic resin. The resin coating is composed of a combination of a hydrophilic polymer for imparting water absorbency and a cross-linking material, or a surface-active material for imparting further wettability. This method can impart antifogging property to the surface of various plastic molded products relatively easily. It is also used in goggles and spectacle lenses.

However, the film thickness is several μm to 10 μm, which is relatively thin. For this reason, it is necessary to consider various properties such as scratch resistance, weather resistance, chemical resistance, and adhesion to a base material of the coating film together with the antifogging performance. These coatings have a low degree of crosslinking in order to have water absorption,
The coating surface has low hardness and is very easily scratched. In short, it is very difficult for the coating method to achieve both antifogging property, impact resistance and scratch resistance.

[0008]

The present invention has been invented in the above technical background, and achieves the following objects.

An object of the present invention is to provide a composite resin molded product having improved antifogging property, impact resistance and scratch resistance, and a method for producing the same.

Another object of the present invention is to provide a composite resin molded article having improved productivity and a method for producing the same.

[0011]

The present invention adopts the following means in order to achieve the above object.

The gist of the present invention is a composite resin comprising a base material formed of a thermoplastic resin and a cellulosic thermoplastic transparent resin having an antifogging property, which is fixed to at least one surface of the base material by molding. It is a molded body. The substrate may be a transparent or opaque thermoplastic resin, but if one or more types selected from polycarbonate, vinyl chloride resin, polyarylate resin, transparent polyolefin resin and styrene copolymer resin are adopted. good.

Cellulose type thermoplastic transparent resins include, for example, triacetyl cellulose (TAC), cellulose acetate (CA), cellulose acetate butyrate (C).
AB), cellulose propionate (CP), and cellulose acetate propionate (CAP). All of these resins are known as resins capable of imparting antifogging property by alkali saponification treatment.

This composite resin molded body comprises a mounting step of mounting a preformed base material on an injection molding die and a cellulose resin molded body by injecting a thermoplastic transparent cellulose resin into a cavity of the injection molding die. And a fog-proofing step of saponifying the formed cellulose resin surface with an alkaline aqueous solution such as caustic soda or caustic potash. The cellulose resin may be molded in advance and the base material may be injected into the cellulose resin molded body.

[0015]

EXAMPLE An example of the present invention will be described below by taking a step of forming a swimming goggle as an example. FIG. 1 is a cross-sectional view when molding a cellulose resin layer in an injection molding die. The goggle body 1 and the lens 2 are integrally molded in advance with another injection molding die. This material is made of a relatively hard resin such as well-known plastics such as polycarbonate (PC) and vinyl chloride resin (PVC). This molding method is a well-known technique, and the content thereof is omitted here, but it is selected from well-known molding conditions according to the resin.

When the lens 2 has a degree, the lens outer surface 3 and the lens inner surface 4 of the lens 2 are spherical.
This spherical surface does not play the role of a lens for swimming swimming goggles in an inaccurate shape depending on the degree of the degree. Therefore, this shape must be precise. The lens for swimming goggles as described above is inserted and placed in the fixed-side mold plate 11 in the injection molding die 10.

In this state, the injection molding die 10, the movable side mold plates 14 and 14, and the slide core 13 move, and the injection molding die 10 is closed. When the injection mold 10 is closed, the cavity 20 is defined. The cavity 20 becomes a lens for swimming goggles by injecting and filling the melted resin forming the antifogging layer. This layer uses a transparent and cellulosic thermoplastic.

The cellulosic plastics are, for example, triacetyl cellulose (TAC), cellulose acetate (CA), cellulose acetate butyrate (CA).
B), cellulose propionate (CP), and cellulose acetate propionate (CAP). These resins are known as resins capable of imparting antifogging property by undergoing alkali saponification treatment. In this example, the cellulosic plastic is molded to a thickness of about 1 mm. In addition, since the outside of the swimming goggle lens is in contact with water, no fog will occur, so no need for anti-fog processing.

Next, an anti-fogging property is imparted by pouring a previously prepared alkaline saponification solution into the cellulose resin layer inside the laminated swimming goggle lens and leaving it to stand for about 3 minutes, followed by washing with water and drying. . The alkali saponification solution is obtained by mixing 10% aqueous solution of caustic soda with 10% alcohol and heating to about 40 ° C. As described above, a lens for swimming goggles having excellent impact resistance, scratch resistance, and anti-fogging property with excellent optical characteristics was obtained.

In this embodiment, cellulose acetate propionate (CA) is used as the cellulosic plastic.
P) which is a product of the Eastman Kodak Company, tenite propionate resin (364A). This resin absorbs strain due to the difference in thermal expansion coefficient from metal,
It is tough and rich in elasticity. Further, it is a transparent resin and has a feature that it can be colored if necessary.
Also, in the case of the prescription lens 2, the shape of the lens can be precisely formed.

Molding conditions Injection pressure: 700 to 2,000, which is the end pressure of the plunger.
0 kgf / cm ² Molding Shrinkage: 2-3 / 1000 cm / cm Second Example FIG. 2 is a sectional view showing another example in which the present invention is applied to a swimming goggle. In the above embodiment, the goggle body and the lens are made of the same material and are molded at the same time.

On the other hand, in this embodiment, the goggle body and the lens are made of different materials and are molded in different steps. That is, the goggle body 1 is made of a relatively hard resin such as polycarbonate (PC), which is a well-known plastic, or vinyl chloride resin (PVC) as in the above-described embodiment, but the goggle body 1 has a hole 1a for mounting the lens 2. Is molded into a shape with. The lens 2 is made of a transparent cellulosic plastic, and is selected from the materials listed in the above embodiment.

The lens 2 is formed by inserting the preformed goggle main body 1 into the injection molding die 10 and injecting a cellulosic thermoplastic resin. At the same time as molding, the lens 2 is fixed to the inner peripheral surface of the hole 1a of the goggle main body 1. To be done. After the molding of the lens 2, the antifogging treatment is performed as in the above embodiment.

As described above, when a cellulosic resin is used as a material for the entire goggles, there are problems in impact resistance and heat resistance, but since it is used only in the lens 2 in this embodiment, These problems are alleviated.

According to this embodiment, it is possible to mold the goggle body 1 in a color different from that of the lens 2 and also in an opaque color. Therefore, various combinations of the color of the goggle body 1 and the color of the lens 2 can be selected, and fashionability is enhanced. When the goggle body is made opaque, the size of the lens is selected within a range that does not interfere with the visual field of human eyes when the goggle is worn.

Molding conditions (1) Polycarbonate injection pressure: 97 kgf / cm ₂ mold temperature at nozzle pressure: 70 ° to 85 ° (2) Cellulose acetate propionate injection pressure: 100 kgf / cm ₂ mold temperature at nozzle pressure: 70 ° to 85 ° Molding shrinkage: 2 to 3/1000 cm / cm Other Examples In the above example, the cellulose resin layer was molded by injection molding, but other known molding methods such as compression molding, lamination molding, blow molding, etc. The method is also good. Further, in the above-mentioned embodiment, the swimming goggles are used, but other windows such as building windows and ski goggles may be used as long as anti-fog processing is required.

Then, an alkali saponification solution is injected into the inside of the lens which is the cellulose resin layer, and the lens is left for a certain period of time and then washed with water to impart antifogging property.

[0028]

As described above in detail, according to the composite resin molded article and the method for producing the same of the present invention, antifogging treatment can be easily performed, scratch resistance, impact resistance is high, and productivity is high. There is a feature of. In particular, when using goggles for swimming with a degree, the shape of the lens can be maintained precisely.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing another embodiment.

[Explanation of symbols]

 1 ... Goggle main body 1a ... Hole 2 ... Lens 3 ... Lens outer surface 4 ... Lens inner surface 10 ... Injection molding die 20 ... Cavity

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical display location B29L 11:00 4F (72) Inventor Kazumitsu Kanemitsu 6 (72) 1066, Daigyouji, Oyama City, Tochigi Prefecture Inventor Toshiaki Hayasaka Kotobuki Mold Co., Ltd., 17 595 Fujikubo, Miyoshi-cho, Iruma-gun, Saitama Prefecture (72) Inventor Shoichi Sakai 1551-72, Mito-cho, Iruma-gun, Saitama Prefecture (72) Inventor Tomio Matsuo 3-3-11 Honkomagome, Bunkyo-ku, Tokyo T & M Co., Ltd.

Claims (5)

[Claims] 1. A composite resin molding comprising a base material formed of a thermoplastic resin and a cellulosic thermoplastic transparent cellulose resin molding having antifogging property, which is fixed to at least one surface of the base material by molding. body. 2. The swimming goggle lens according to claim 1, wherein the base material is formed of a transparent thermoplastic resin, and the thermoplastic transparent cellulose resin molding is laminated on the lens. And a composite resin molded body. 3. The lens according to claim 1, wherein the base material is a goggle body of swimming goggles, and the thermoplastic transparent cellulose resin molding is a lens fixed to an inner peripheral surface of a lens mounting hole of the goggle body. A composite resin molded body characterized by being present. 4. A method of manufacturing a composite resin molded body according to claim 1, which is selected from claims 1, 2, and 3, wherein a mounting step of mounting the preformed base material on an injection molding die, Cellulose resin molding step of molding the thermoplastic transparent cellulose resin molding by injecting the thermoplastic transparent cellulose resin into the cavity of the injection molding die, and alkali-saponifying the molded thermoplastic transparent cellulose resin. An anti-fog treatment step for imparting anti-fog property, and a method for producing a composite resin molded article, comprising: 5. A selected one from claims 1, 2, 3, and 4.
In the paragraph, the base material is transparent polycarbonate, vinyl chloride resin,
A method for producing a composite resin molded body, which is selected from any one resin selected from a methylmethacrylic resin, a polyarylate resin, a transparent polyolefin resin and a styrene copolymer resin.