JPH05337960A - Thermal polymerization of molded composite optical part - Google Patents

Abstract

(57) [Summary] [Object] To provide a good polymerization condition for a thermosetting resin when a thermosetting resin monomer is interposed between a glass substrate and a mold. [Structure] A method for heating and polymerizing a molded composite optical component, in which a mold is heated at an initial heating rate of 90 to 110 ° C / 5 minutes, and then the mold temperature is maintained at 100 to 110 ° C to complete polymerization.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for heat-polymerizing a molded composite optical component in which a synthetic resin layer made of a thermosetting resin is adhered and molded on a glass base material.

[0002]

2. Description of the Related Art A molded composite optical component, such as a composite aspherical lens, formed by molding a glass base material and a synthetic resin layer onto a preprocessed glass base material and dropping a measured resin material on the glass base material. The resin material is stretched with a mold and then polymerized and bonded to a glass base material.

As the resin material, a thermosetting resin, an ultraviolet curable resin or the like is used, but the ultraviolet curable resin has the following problems. The composite aspherical lens is obtained by adhering and molding an aspherical synthetic resin layer on a spherical glass. Therefore, if the amount of aspherical surface is increased, the difference in resin thickness between the central portion and the peripheral portion of the lens inevitably increases. However, since the ultraviolet curable resin is a resin that is polymerized and cured when it is irradiated with ultraviolet rays, it has a limited thickness due to the problem of absorption of ultraviolet rays. The speed is different, and as a result, curing distortion occurs and the performance as a lens deteriorates. Specifically, the maximum thickness is around 0.33 mm, and the maximum thickness difference is 0.20 mm.
The reality is that it is restricted before and after. For this reason, the effect to be used is limited as an aspherical lens which is required to have a large aperture and high performance like a photographic lens. Further, the ultraviolet curable resin tends to become yellow as a result of absorbing ultraviolet rays, and as a photographic lens, there is a problem in color reproducibility.

On the other hand, thermosetting resins have recently been drawing attention because they do not have the above problems of ultraviolet curable resins. When this thermosetting resin is polymerized and molded on a glass lens, no optical strain remains inside, no residual stress occurs inside, high processing accuracy (surface accuracy), curing speed ( It is required that the polymerization rate) be fast, that is, that the processability be good. In particular, the resin material layer of the compound aspherical lens is 1/100 m when it is a thermosetting resin.
Since it is as thin as m to several mm, it requires special heating conditions different from those for general thermosetting resins.

[0005]

It is an object of the present invention to provide polymerization conditions satisfying the above requirements in a method of heat-polymerizing a molded composite optical component which is formed by polymerizing a thermosetting resin on a glass substrate. To do.

[0006]

SUMMARY OF THE INVENTION In the heat polymerization method of the present invention, a thermosetting resin monomer is interposed between a glass base material and a mold, and the mold is heated to deposit and mold a polymer on the glass base material. In the heat polymerization method for molded optical parts, the mold is
Heat at an initial heating rate of ~ 110 ° C / 5 minutes, then 10
It is characterized in that it is maintained at 0 to 110 ° C. to complete the polymerization.

In the present invention, the initial heating rate is 90 to 110 ° C.
The first feature is that it is set to / 5 minutes. If the initial heating rate exceeds 110 ° C./5 minutes, that is, if the heating rate is faster than the above range, the polymerization reaction runs out of control, causing problems such as foaming of the resin material, residual internal strain, and deterioration of surface accuracy. .. If the initial heating rate is lower than 90 ° C / 5 minutes, the workability will be poor. By this initial heating, the monomer is provisionally cured. Temporary curing refers to a state in which the lens and the mold are bonded together via a resin material and the two do not separate unless an external force is applied. This temporarily cured resin material has a high viscosity, and the central portion has already been cured.

Next, in the present invention, after the mold reaches 90 to 110 ° C. by this initial heating, the mold is maintained at that temperature to complete the polymerization. By this temperature holding step, the resin material temporarily cured in the initial heating step is cured with good shape accuracy without internal strain.

The thickness of the polymer interposed between the glass substrate and the mold is preferably 1/100 mm to several mm.
The method of the present invention can be applied to optical components other than the composite aspherical lens, but when applied to the composite aspherical lens, the glass base material is a spherical glass lens, and the thickness of the spherical glass lens is A polymer layer composed of a non-uniform aspherical layer is formed.

The thermosetting resin is preferably an epoxy resin. As epoxy resin, Bisfer A
Type, bisfer AD type or bisfer F type epoxy resin can be used. These epoxy resins are cured with acid anhydride type, amine type or other curing agents.

Even if the thermosetting resin is directly formed on the glass base material without interposing the silane coupling agent layer or the like as the intermediate layer, sufficient adhesion can be obtained.

[0012]

The present invention will be described below with reference to the drawings.
The illustrated example shows a process of forming a compound aspherical lens,
A thermosetting resin material 12 preliminarily weighed according to the amount of aspherical surface is dropped on the glass spherical lens 11 which has been previously processed into a predetermined spherical surface. Next, the mold 14 having the aspherical surface 13 is brought close to the resin material 12 by a predetermined distance, and the resin material 12 is thinly spread on the glass lens 11. When the mold 14 is heated in this state to heat the resin material 12, the polymerization of the monomer proceeds, and the thermosetting resin material 12 having the aspherical surface 13 transferred is bonded onto the glass lens 11 to form a composite. The aspherical lens 15 is obtained. A mold release agent is previously applied to the surface of the aspherical surface 13 of the mold 14.

According to the present invention, in the method for heat-polymerizing the composite aspherical lens 15 formed as described above, in order to polymerize and cure the thermosetting resin material 12, as a first step, the mold 14 is heated at an initial heating rate. It is heated at 90 to 110 ° C. for 5 minutes to be temporarily cured, and as a second step, the mold 14 is used.
Is maintained at 100 to 110 ° C. to complete the polymerization.

FIG. 2 is a graph showing the heating rate and temperature range by the heat polymerization method according to the present invention. The first area A is an initial heating area, and the second area B is a constant temperature holding area. The hatched range is the range according to the present invention. According to the heating rate and temperature conditions in the hatched regions A and B, the thermosetting resin to be polymerized and molded does not have optical strain inside the thermosetting resin material 12 and does not cause residual stress inside. It was confirmed that high processing accuracy (surface accuracy) was obtained, the curing speed (polymerization speed) was fast, and the workability was excellent.

On the other hand, in the area C deviating from the hatched areas A and B to the upper side, the polymerization reaction goes out of control, resulting in problems such as foaming of the thermosetting resin material 12, residual internal strain, and deterioration of surface accuracy. Occurs. Further, in the region deviated to the lower side, the polymerization reaction is slow and the workability is poor.

The thickness of the thermosetting resin material 12 is 1/100 mm
The thickness can be about several mm, and the thickness can be changed according to the amount of aspherical surface. Although the present invention is applied to the composite aspherical lens in the above-mentioned embodiment, the present invention is also applicable to other composite optical elements in which a synthetic resin material is molded on a glass base material.

Next, preferred compounds as the thermosetting resin material 12 of the present invention will be shown. A, the following compounds (X) and (Y) compound (X) bisphenol A type epoxy resin as a main agent, and the molecular structure are shown below.

[Chemical formula 1] Compound (Y) One or a mixture of two or more of the following compounds, and the mixing ratio are arbitrary. The molecular structure of diglycidyl phthalate, diglydizyl hexahydrophthalate, diglycidyl tetrahydrophthalate, is shown below.

[Chemical formula 2] The compounds (X) and (Y) are from 10 to 90:90 to 10
It is mixed in a ratio of parts by weight.

B, the following compound (Z) as a curing agent: Compound (Z) One or a mixture of two or more acid anhydride curing agents represented by the following general formulas ,.

[Chemical formula 3]

C, benzyldimethylamine as a curing accelerator, and the molecular structure are shown below.

[Chemical formula 4] D, phosphate compound

The above A, B, C, and D are mixed in the following proportions to obtain the resin material 12. A: 40 to 60 parts by weight B: 60 to 40 parts by weight C: 0 to 5 parts by weight D: 0 to 5 parts by weight

Next, the present invention will be described with reference to Examples and Comparative Examples. "Example 1" Bisphenol A glycidyl ether and hixahydrophthalic acid glycidyl ether, and the following chemical formula

[Chemical formula 5] An acid anhydride-based curing agent represented by, benzyldimethylamine as an additive, the following chemical formula

[Chemical formula 6] 50: 50: 55: 1:
The composition 12 was mixed, and the mixture 12 was interposed between the aspherical mold 14 and the spherical glass lens 11 as shown in FIG. Resin layer 12 molded at this time
The outer peripheral portion had a thickness of about 0.1 mm, the central portion had a thickness of about 0.3 mm, and the resin amount was about 0.4 g. The curing process was divided into an initial curing and a post-curing to facilitate the control of the polymerization reaction. The temperature rising rate of the initial curing was assumed to have a certain amount of change that reached 100 ° C. in 5 minutes, and after reaching 100 ° C., it was held for 15 minutes. After this, further post-cure 12
The temperature was raised to 0 ° C. and maintained for 15 minutes to finish heating. After that, the lens-resin composite body 15 was released from the aspherical mold 14, and the resin surface was observed. As a result, no optical defect was observed and it was sufficient as an objective lens for photography. A release agent was previously applied to the surface 13 of the aspherical mold 14.

"Example 2" The initial polymerization rate of Example 1 was 5
The temperature gradient was changed to 110 ° C. per minute, and the others were changed to Example 1
Same as. When observing the molded resin surface,
No optical defect was observed, and it was sufficient as a photographic lens.

"Example 3" The initial polymerization rate of Example 1 was set to 5
The temperature was changed to a temperature gradient of 90 ° C. per minute, and the holding time was set to 20 minutes. Others were the same as in Example 1. When observing the molded resin surface, no optical defects were observed,
It was a good photographic lens.

"Comparative Example 1" The initial polymerization rate of Example 1 was 5
The temperature was changed to a temperature gradient of 80 ° C. per minute, and the holding time was set to 20 minutes. Others were the same as in Example 1. The molded lens did not complete the curing reaction of the resin material and could not be used as a lens. Was enough.

Comparative Example 2 The initial polymerization rate of Example 1 was 5
The temperature gradient was changed to 120 ° C. for 1 minute, and the others were changed to Example 1
Same as. The resin surface of the molded lens had irregularities due to the runaway of the curing reaction, and could not be used as a lens.

[0026]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, a thermosetting resin monomer is interposed between a glass base material and a mold, and the mold is heated to deposit and mold a polymer on the glass base material. In the heating polymerization method of the molded optical parts, the initial heating rate of the mold and the subsequent constant temperature holding temperature were set in a preferable range, so that the resin material to be polymerized and hardened was obtained with high accuracy and without optical and mechanical distortion. Moreover, it can be processed with good productivity.

[Brief description of drawings]

FIG. 1 is a schematic view showing a procedure for molding a thermosetting resin material onto a glass base material to which the present invention is applied.

FIG. 2 is a graph showing the initial heating rate and the holding constant temperature range of the polymerization method of the present invention.

[Explanation of symbols]

 11 Glass Lens 12 Thermosetting Resin Material 14 Mold A Initial Heating Area B Constant Temperature Holding Area

Claims (3)

[Claims] 1. A method for heat-polymerizing a molded optical component, wherein a thermosetting resin monomer is interposed between a glass base material and a mold, and the mold is heated to adhere and mold the polymer onto the glass base material. A method for heating and polymerizing a molded composite optical component, characterized in that the above-mentioned mold is heated at an initial heating rate of 90 to 110 ° C / 5 minutes, and then the mold temperature is maintained at 100 to 110 ° C to complete the polymerization. 2. The polymer according to claim 1, wherein the thickness of the polymer is
A heat polymerization method of 1/100 mm to several mm. 3. The heat polymerization method according to claim 1, wherein the glass substrate is a spherical lens and the polymer is an aspherical layer.