JPH053821B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a thermoplastic synthetic resin eyeglass frame having an elegant pattern.

(Prior Art) Conventionally, fiber-based resins such as celluloid and acetyloid have been used as materials for high-grade synthetic resin eyeglass frames, and they are usually supplied in the form of sheets with patterns, and these sheets are cut. Glass frames were created through a very labor-intensive process of cutting, bending, and so on.

Eyeglass frames made using this method have elegant patterns that are close to nature, such as shell patterns, amber patterns, wood grain patterns, marble patterns, and leather patterns, and their commercial value is extremely high. However, it had the disadvantage that the manufacturing process required to create the pattern was too long, and the price of the sheet was extremely high, making the cost extremely high. Moreover, cellulose resin has the disadvantage of deforming and deteriorating due to heat and moisture, so it is inexpensive, resistant to heat and moisture, and eyeglass frames that are not affected by hair styling products, sweat, and cosmetics. The emergence of eyeglass frames with a pattern made of synthetic fibers was eagerly awaited.

(Problems to be Solved by the Invention) Therefore, the present invention aims to reduce the weight of the eyeglass frame.
Moreover, it is an object of the present invention to provide an eyeglass frame which is not deformed by heat and moisture during use and is not attacked by sweat, cosmetics, and hair styling products.

(Means for Solving the Problems) The present invention includes a first step of molding a thermoplastic resin into an eyeglass frame using a thermoplastic resin injection molding machine, and a surface portion of the molded eyeglass frame. After contacting part or all with a sublimable dye,
A pattern characterized in that it is obtained through a second step of leaving it under high temperature conditions of 140°C to 170°C for 5 minutes to 1 hour, and a third step of painting part or all of the surface of the eyeglass frame with paint. This is a method of manufacturing an eyeglass frame having a pattern.

To explain the present invention in more detail, polymethylpentene resin is a transparent thermoplastic resin having the following structural formula.

(Weight average molecular weight: 400,000 to 1,000,000) Since this polymethylpentene resin is thermoplastic, it can be easily melt-molded using an injection molding machine for thermoplastic resins. This point is an advantage that is fundamentally different from thermosetting resins such as epoxy resins (obtyl), polyester resins, urethane resins, and silicone resins.

Thermoplastic resins have the advantage of being easily molded by hot melt molding, but on the other hand, they also soften, melt, and deform due to heat, and are usually subjected to various treatments at temperatures above the heat distortion temperature of the resin. will not be performed. However, although this polymethylpentene resin has a low heat distortion temperature of 85°C to 100°C (ASTM D648), it does not cause any deformation that would cause practical problems even if it is left at high temperatures of 140°C or higher. is other thermoplastic resin, such as polymethyl methacrylate resin,
Its properties are completely different from those of polycarbonate resin, transparent nylon resin, etc. This is the reason why polymethylpentene resin was used as the material for the eyeglass frame of the present invention.

The injection molding machine for thermoplastic resin used in the present invention may be one commonly used.

The methods of bringing the sublimable dye into contact with the surface of the eyeglass frame in the second step include: Direct application of sublimable dye powder onto the surface of the eyeglass frame; Method of applying or spraying in the form of ink, solution, or paint; Paper, Synthetic There is a method using the so-called "transfer paper method" in which sublimation dye ink is coated or printed on paper, metal foil, etc., and the paper, synthetic paper, metal foil, etc. is wrapped around the eyeglass frame. In the second step, after contacting part or all of the surface of the eyeglass frame with sublimable dye,
Leave it for 5 minutes to 1 hour, preferably 20 minutes to 40 minutes, under a high temperature condition of 170 degrees Celsius.This process allows the sublimation ink to diffuse into the interior of the eyeglass frame, giving the pattern a deep three-dimensional effect. can. This is a pattern that cannot be created by simple methods such as painting or dyeing. The leaving temperature in the second step is 140°C to 170°C; if it is too low, the dye will not sublimate and is not practical. Also, 170℃
In the above case, deformation of the eyeglass frame occurs, which is a problem. Also, leave it for 5 minutes to 1 hour, preferably 20 minutes to 40 minutes.
However, if the left time is too short, the pattern will not be sufficiently formed, and if the left time is too long, it is a waste of time.

Any paint can be used in the third step as long as it adheres closely to the polymethylpentene resin eyeglass frame and has practical durability as a coating film. Examples include acrylic paints, polyurethane paints, epoxy paints, polyester paints, aminoalkyd paints, melamine paints, and the like. This paint may be applied by any commonly used method, but any method such as spray painting, brush painting, dipping, electrostatic airless painting, etc. can be used.

In the third step, a part or all of the surface of the eyeglass frame obtained in the second step is coated with paint to prevent the surface of the eyeglass frame from being easily scratched, to prevent the pattern from fading, It is indispensable for the purpose of increasing the gloss of the surface or creating more complex patterns by adding colorants to the paint.

Further, the present invention will be explained in detail by examples, but the present invention is not limited to these examples.

(Example) In the first step, polymethylpentene resin pellets are melted in a thermoplastic resin injection molding machine to a resin temperature of 300°C and injection molded into a mold for an eyeglass frame. A resin eyeglass frame was obtained. This eyeglass frame was treated to remove burrs and parting lines.

In the second step, the three-color cross-over pattern transfer paper, which has been previously screen printed with sublimable dye ink, is wrapped around the eyeglass frame so that the sublimable ink and the eyeglass frame are in as close contact as possible. After that, it was left in an oven at 150°C for 30 minutes and then taken out, and after cooling at room temperature, the transfer paper was removed.

In the third step, the eyeglass frames obtained in the second step above were spray-painted with a colorless polyurethane resin paint (manufactured by Mikuni Paint KK, trade name: NY Nylon Clear), left indoors for 2 hours, and then 50℃
The paint was left in an oven for 3 hours to harden.

The thus obtained eyeglass frame had an excellent pattern, and the surface of the eyeglass frame also had excellent gloss. Further, no practical deformation occurred at all.

(Example) The present invention was carried out as follows using the eyeglass frame obtained in the first step of the example.

In the second step, a floral pattern is drawn on the surface of the eyeglass frame using a brush with sublimable dye ink, then left in an oven at 145℃ for 1 hour, taken out, cooled at room temperature, and then soaked in ethyl alcohol. Excess sublimable ink on the surface of the eyeglass frame was removed using soaked gauze.

In the third step, the eyeglass frames obtained in the second step above are spray-painted with an acrylic resin paint (Nippon Kagaku Toyo Co., Ltd., trade name: Neochemica Acryl C) colored in a light red transparent color. After being left at room temperature for 30 minutes, the glasses were left in an oven at 150°C for 30 minutes to harden the paint, and then taken out and allowed to cool.

The thus obtained eyeglass frame has a complex and excellent pattern as the sublimable dye ink used in the second step is partially transferred to the paint film applied in the third step.
The surface gloss was also excellent. Further, no practical deformation occurred.

Comparative Examples 1, 2, and 3 The polymethylpentene resin in the example was replaced with polymethyl methacrylate resin (Mitsubishi Rayon Co., Ltd., product name: Acrypet.Grade).
VH), polycarbonate resin (Teijin Kasei Ltd., product name: Panlite. Grade L1225),
Glass frames were obtained by changing to transparent nylon resin (Ms Japan Co., Ltd., product name: Grilamid, grade TR-55LX) and molding under the optimum injection molding conditions for each resin.

Next, as in the second step of the example, the sublimable dye was brought into contact with the surface of each eyeglass frame using transfer paper, and then left in an oven at 150°C for 30 minutes.
When I took it out, it was severely deformed and was practically unusable. By the way, the heat distortion temperature of each resin is acrylic. Grade VH 100℃, Panlite. Grade L1225 120℃, Grillamide. Grade TR-55LX 95°C was the same as or higher than polymethylpentene resin.

Furthermore, depending on the purpose and to increase commercial value, ultraviolet absorbers, antistatic agents, colorants, luminescent agents, infrared absorbers, metal powders, etc. can be added to the paint used in the present invention. .

(Effects) As is clear from the above, the eyeglass frames obtained by the present invention are approximately 40% lighter than eyeglass frames made of cellulose resin, and are not deformed by heat or moisture during use, and are free from sweat. It is not affected by cosmetics, hair styling products, and is an extremely excellent invention from a social perspective.

Claims (1)

[Claims] 1. A first step of molding a thermoplastic polymethylpentene resin into an eyeglass frame using an injection molding machine for thermoplastic resin, and after contacting part or all of the surface of the molded eyeglass frame with a sublimable dye. ,140℃
The pattern pattern consists of a second step of leaving it under high temperature conditions of ~170°C for 5 minutes to 1 hour, and a third step of painting part or all of the surface of the eyeglass frame obtained in the second step with paint. A method of manufacturing an eyeglass frame having the following.