JP2003071852A - Plastic lens manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a plastic lens of good quality by suppressing the generation of a flaw in a plastic lens manufacturing method having a precuring process due to active energy beam. SOLUTION: In the precuring process, the plastic lens is successively irradiated with active energy beam while changing the angle of irradiation of the active energy beam or simultaneously irradiated with a plurality of active energy beams mutually having crossing angles.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a plastic lens, and more particularly to a method for manufacturing a plastic lens having a short polymerization time and good quality.

[0002]

2. Description of the Related Art The casting polymerization method is widely used as a method for producing a plastic lens such as a spectacle lens which requires high performance. In the casting polymerization method, a composition for plastic lenses is injected into a lens polymerization type, and heat treatment and / or irradiation with active energy rays such as ultraviolet rays is performed to polymerize and cure the composition for plastic lenses to obtain a desired plastic lens. Is the way.

The method of polymerizing and curing the plastic lens composition by irradiating it with active energy rays requires a long polymerization time of about 20 hours in contrast to the heat polymerization method of heat treatment, which takes several minutes. Since it cures in the polymerization time, it is possible to shorten the delivery time and reduce the inventory, making it a production method suitable for build-to-order manufacturing.

FIG. 5 shows an example of a manufacturing process of a plastic lens by irradiation with active energy rays. First, FIG.
As shown in (a), two circular glass molds 11 and 12
And two glass molds 1 separated from each other at a predetermined interval.
Glass type 1 with adhesive tape 13 wrapped around 1, 12
The gap between 1 and 12 is sealed to form a cavity 14,
A lens polymerization mold 10 is produced.

Next, as shown in FIG. 5 (b), the injection lens 20 is pierced through the adhesive tape 13 with the lens polymerization mold 10 set vertically, and the liquid plastic lens composition 30 is filled with the cavity of the lens polymerization mold 10. Inject into 14.

Next, as shown in FIG. 5 (c), in a pre-curing step, the ultraviolet rays are radiated from the ultraviolet ray irradiating source 40 by the reflecting plate 41 while the hole 131 through which the injection needle of the adhesive tape 13 is inserted is upwardly lens-polymerized. The plastic lens composition 30 is concentrated in the mold 10 and irradiated for several seconds, and the plastic lens composition 30 is prepolymerized and gelled so that the plastic lens composition 30 does not leak from the hole 131 through the injection needle.

Next, as shown in FIG. 5 (d), the polymerization reaction of the gelled plastic lens composition 30 is irradiated with ultraviolet rays from an ultraviolet ray irradiation source 51 in an ultraviolet ray irradiation furnace 50,
In some cases, thermal polymerization is added to the completion. After that, the adhesive tape 13 is peeled off, and the glass molds 11 and 12 are released from the mold to obtain a plastic lens.

[0008]

[Problems to be Solved by the Invention] However, in the past,
Although there was no problem with the plastic lens composition having a short gelling time in the pre-curing step, the plastic lens composition having a relatively long gelling time in the pre-curing step has It has been confirmed that there is a problem that aberrations and striae-like defects occur that cause a difference in the diopter between the vertical direction and the vertical direction.

In particular, when a method of irradiating a composition for a plastic lens containing an ultraviolet absorber with an active energy ray to cure the composition is adopted in order to impart an ultraviolet absorbing ability also to the active energy ray-curable plastic lens. Moreover, the gelation time in the pre-curing step is relatively long, and these defects are remarkable.

In order to suppress striae-like defects, frosted glass is arranged between the active energy ray source and the lens polymerization type,
It has been proposed to scatter and diffuse active energy rays with frosted glass, and to irradiate a lens polymerization type with active energy rays having no directionality to cure a composition for plastics (Japanese Patent Publication No. 7-206700).

However, as a result of the study by the present inventor, the method of scattering active energy rays by frosted glass can suppress striae-like defects, but cannot suppress the occurrence of aberration.

The present invention has been made in view of the above problems, and in a method of manufacturing a plastic lens having a pre-curing step using active energy rays, generation of aberrations and striae-like defects is suppressed and the quality is good. An object of the present invention is to provide a plastic lens manufacturing method capable of manufacturing a plastic lens.

[0013]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventor has found that the active energy rays in the pre-curing step are linear and the activity emitted from the linear irradiation source is The energy rays are intensively applied to the lens-polymerized type almost in parallel with the reflection by the reflection plate, and the reaction direction of the active energy rays causes the difference in the frequency in the direction orthogonal to the direction parallel to the active energy rays. It was found that aberrations and striae defects occur.

Therefore, in the first invention, polymerization of the active energy rays is performed by sequentially changing the relative angle between the linear irradiation source and the lens polymerization type in the direction parallel to the diameter direction of the lens polymerization type in the pre-curing step. It has become possible to manufacture a plastic lens that cancels the reaction directionality and suppresses the occurrence of aberrations and striae-like defects.

Further, in the second invention, by simultaneously irradiating using a plurality of linear irradiation sources having mutually intersecting angles in a direction parallel to the diametrical direction of the lens superposition type,
Cancel the direction of the polymerization reaction of active energy rays,
It has become possible to manufacture plastic lenses that suppress the occurrence of aberrations and striae defects.

The relative angle or intersection angle between the linear irradiation source and the lens superposition type is 180 ° or 360 ° in order to uniformly irradiate.
The most effective way is to make the angle approximately equal.

Further, the photopolymerizable composition containing an ultraviolet absorber and a photopolymerization initiator having absorption in the visible light region has a relatively long gelation time in the pre-curing step and has an aberration due to the directionality of active energy rays. The application of the present invention is effective because the above-mentioned problem easily occurs.

Therefore, according to the first aspect of the present invention, the plastic lens composition filled in the lens polymerization type is irradiated with an active energy ray from one side or both sides of the lens polymerization type to obtain the plastic lens composition. In the method for producing a plastic lens, which comprises a pre-curing step of pre-polymerizing and a main curing step of completing the polymerization by subjecting the pre-polymerized composition for a plastic lens to irradiation with active energy rays and / or heat treatment, The process is
A plastic lens characterized by sequentially irradiating active energy rays by changing a relative angle between the lens superimposing type and a linear irradiation source for emitting active energy rays in a direction parallel to the diameter direction of the lens superimposing type. A manufacturing method is provided.

According to a second aspect of the invention, the composition for plastic lenses filled in the lens polymerization type is irradiated with active energy rays from one side or both sides of the lens polymerization type to prepolymerize the composition for plastic lenses. In the method for producing a plastic lens having a pre-curing step of: and a main curing step of completing the polymerization by subjecting the pre-polymerized composition for a plastic lens to active energy ray irradiation and / or heat treatment, the pre-curing step comprises: A method for producing a plastic lens is characterized in that active energy rays are simultaneously irradiated from each of a plurality of linear irradiation sources having an intersecting angle in a direction parallel to a diameter direction of the lens superposition type.

According to a third aspect of the present invention, in the method for producing a plastic lens according to the first or second aspect, the relative angle between the lens superposition type and the linear irradiation source or the intersecting angle is 180 ° or 360 °. Provided is a method of manufacturing a plastic lens, which is characterized in that the angles are substantially evenly divided.

According to a fourth aspect of the present invention, in the method of manufacturing a plastic lens according to the second aspect, the plurality of linear irradiation sources are arranged on both sides of the lens superposition type plastic lens. A method for manufacturing the same is provided.

According to a fifth aspect of the present invention, in the method for producing a plastic lens according to the first or second aspect, the composition for a plastic lens comprises 100 parts by weight of a raw material monomer and 0.1 to 5 parts by weight of an ultraviolet absorber. Parts, and 0.0005 to 5 parts by weight of a photopolymerization initiator having an absorption property in the visible light region are provided.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the method for producing a plastic lens of the present invention will be described below, but the present invention is not limited to the following embodiments.

As described above, the method for producing a plastic lens of the present invention includes the preliminary curing step and the main curing step. In the first curing step, in the first invention, the irradiation angle of the active energy ray is changed. Irradiation is performed sequentially, and in the second invention, a plurality of active energy rays having mutually intersecting angles are simultaneously irradiated.

The steps in the method for producing a plastic lens of the present invention are improved in the pre-curing step as compared with the conventional method, and other steps are not particularly changed.

First, as shown in FIG. 5A, a glass mold 11 for forming a convex surface and a glass mold 12 for forming a concave surface are prepared, and two glass molds 11 and 12 are separated at a predetermined interval.
Wrap, for example, adhesive tape 13 around the
While fixing the glass molds 11 and 12 with the glass molds 11,
The gap between 12 is sealed. As a result, the lens polymerization mold 10 having the cavity 14 surrounded by the glass molds 11 and 12 on the both sides and the adhesive tape 13 on the side faces is manufactured. The lens stacking mold 10 is made up of a glass mold 11,1 by a gasket.
2 may be fixed. The lens polymerization type 10 is
When manufacturing a finish lens where both sides are glass type and the final lens surface is transferred, and when a slightly thick semi-finished lens in which one lens surface is transferred by the glass type and the other surface is formed by polishing is used. There are cases where it is produced.

Next, as shown in FIG. 5 (b), the lens superposition mold 10 is made vertical and the injection needle 20 is placed on the uppermost adhesive tape 1.
Liquid composition 30 for plastic lens
1 through the injection needle 20
Inject into 4. The composition for plastic lenses will be described later.

Next, the pre-curing step of the present invention is performed. In the pre-curing step, the liquid plastic lens composition 30 in the lens polymerization mold 10 is irradiated with an active energy ray, pre-polymerized to gel and lose fluidity, and the plastic is injected from the hole 131 through the injection needle 20. The purpose of the present invention is to prevent the lens composition 30 from leaking, alleviate the stress associated with polymerization shrinkage, reduce residual stress strain inside the lens, and obtain a plastic lens with good surface accuracy.

In the first aspect of the present invention, as described above, linear irradiation for emitting active energy rays to the lens superimposing mold 10 in a direction parallel to the diameter direction of the lens superimposing mold 10 (direction orthogonal to the lens center axis). The relative angle with the source 40 is changed, and active energy rays are sequentially irradiated.

As the irradiation method, the pre-curing step is divided into a plurality of steps for irradiation while intermittently changing the relative angle of the linear irradiation source 40 with respect to the lens polymerization mold 10, or the linear irradiation with respect to the lens polymerization mold 10 is performed. Irradiation is performed while continuously changing the relative angle of the irradiation source 40. The lens polymerization mold 10 is rotated, or the linear irradiation source 40 is rotated. Alternatively, the linear irradiation source 40 for the lens superimposing mold 10 is rotated by rotating both the lens superimposing mold 10 and the linear irradiation source 40.
The relative angle of can be changed.

A linear irradiation source 40 for the lens stack type 10
In order to cancel the directionality of the reactivity of the active energy ray, the relative angle of is preferably an angle that divides 180 ° or 360 ° substantially equally when irradiating in a divided manner. For example, 90 ° when divided into two, 60 ° or 120 ° when divided into three, and 45 ° or 90 ° when divided into four. On the other hand, when the irradiation angle is continuously changed, it is preferable to rotate the lens polymerization mold 10 or the linear irradiation source 40 once or twice or more during the pre-curing time.

When the irradiation is divided, the lens polymerization type 1
0 and the position of the linear irradiation source 40 may be fixed, respectively, or a plurality of linear irradiation sources 40 may be used, and the linear irradiation sources 40 with different angles are arranged and the lens superposition type 10 is sequentially arranged. Irradiation may be performed by arranging in front of each linear irradiation source 40. Alternatively, the first irradiation may be performed from one side of the lens overlapping type, and the second irradiation may be performed from the other side of the lens overlapping type so that irradiation is finally performed from both sides.

The illuminance of the entire prepolymerization step is 20 to 600.
range of mW / cm ^2, in particular in the range of 60~200mW / cm ² is preferred. The irradiation energy is, for example, 50 m.
J / cm ² ~30J / cm ^2, especially in the range 100 mJ / c
The range of m ^{2 to 4} J / cm ² is preferable. Irradiation time is from 1 second
It is a range of several minutes.

In the case of divided irradiation, when the polymerization rate is higher toward the beginning of the polymerization, the irradiation time can be assigned so that, for example, the progress of the polymerization is almost the same. Further, the irradiation time in the prepolymerization step may be an evenly divided irradiation time.

As the linear irradiation source, when ultraviolet rays are used as the active energy rays, an ultraviolet ray source which emits ultraviolet rays (including a visible light region) in the wavelength range of 200 to 800 nm can be used. Specifically, a chemical lamp, a xenon lamp, a mercury short arc lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, a fusion lamp, etc. can be used. X besides UV
Active energy rays such as rays, γ rays and electron rays can be used.

The atmosphere in the prepolymerization step may be air or an inert gas atmosphere. Room temperature is sufficient, but heating or cooling may be performed in some cases.

FIG. 1 shows the pre-curing step in the case where the pre-curing step is divided into the first pre-polymerization step and the second pre-polymerization step and the irradiation is performed twice. FIG. 1A is a conceptual diagram showing a positional relationship between a lens-stacked vertical section and a linear irradiation source.
(B) is a conceptual diagram in the direction of the central axis of the lens overlapping type showing the positional relationship between the linear irradiation source and the lens overlapping type. Figure 1 (a)
And (b), (1) is the first prepolymerization step,
(2) shows the second prepolymerization step.

In the first pre-polymerization step, the linear irradiation source 40 is moved in the horizontal direction, for example, in the horizontal direction while maintaining the arrangement in which the hole 131 through which the injection needle is inserted in the lens polymerization type is at the top.
It is arranged on the front side of the lens superimposing mold 10 in parallel with the diameter direction of 0. In FIG. 1 (1), the active energy ray from the linear irradiation source 40 is intensively applied to the glass mold 11 side for forming the convex surface of the lens superimposing mold 10 substantially parallel to the horizontal direction by the reflector 41. The polymerization type 10 and the linear irradiation source 40 are arranged.

Then, an active energy ray is emitted from the linear irradiation source 40, and the plastic lens composition 30 in the lens polymerization mold 10 is irradiated with the active energy ray. In the first prepolymerization step, the plastic lens composition 30 is gelled to such an extent that the composition 30 does not leak from the hole 131 through the injection needle.

Next, in the second preliminary polymerization step, the lens polymerization mold 10 or the linear irradiation source 40 and the reflection plate 41 are rotated, and the relative angle between the lens polymerization mold 10 and the linear irradiation source 40 is changed to the first preliminary polymerization. Change with the process. Lens stacking type 10 and linear irradiation source 4
It is preferable that the relative angle with respect to 0 changes by 90 ° with respect to the first prepolymerization step. In FIG. 1 (2), the linear irradiation source 40 is set in the vertical direction while the position of the lens superimposing mold 10 is left unchanged, that is, the lens superimposing mold 10 and the linear irradiation source 40 in the first pre-polymerization step.
It is arranged at a position rotated by 90 ° relative to.
Of course, the linear irradiation source 40 may be fixedly arranged, and the lens superimposing mold 10 may be rotated. Such a lens superposition type 10 and the linear irradiation source 40 are arranged, and the linear irradiation source 4
The active energy ray is emitted from 0, and the lens polymerization type 10
The composition 30 for a plastic lens in the above is irradiated with an active energy ray to gel the composition 30 for a plastic lens almost completely.

In FIG. 1, the linear irradiation source 40 is arranged on the central axis of the lens overlapping mold 10, but the position of the linear irradiation source 40 is parallel to the diameter direction of the lens overlapping mold 10. As long as it is sufficient, it may be deviated from the central axis of the lens superimposing mold 10.

Since the irradiation directions of the active energy rays to the lens polymerization mold 10 in the first pre-curing step and the second pre-curing step are orthogonal to each other, the directivity of the polymerization reaction of the active energy rays is canceled and the preliminary A uniform gelation can be achieved in the curing step, and it is possible to suppress the occurrence of aberrations and striae-like defects having different frequencies depending on the part in the plastic lens.

FIG. 2 shows an example in which the preliminary polymerization step is divided into three times. In this example, the lens superposition type is rotated. When the prepolymerization step is divided into three times, the relative angle between the lens polymerization type and the linear irradiation source is 60.
Irradiate by changing every ° or 120 °. First, in the first pre-irradiation, as shown in FIG. 2A, with respect to the lens polymerized mold 10 having the hole 131 through which the injection needle is placed,
For example, the linear irradiation source 40 is horizontally arranged and irradiation is performed. Next, in the second preliminary irradiation, as shown in FIG. 2B, the lens polymerizing mold 10 is rotated by 120 ° and fixed, and irradiation is performed. Next, in the third preliminary irradiation, as shown in FIG.
As shown in (3), the lens polymerization mold 10 is further rotated by 120 ° and fixed, and irradiation is performed. In addition, in FIG.
Are omitted, the active energy rays parallel to the linear irradiation source 40 are integrated with the linear irradiation source 40, and the lens polymerization type 10
It is designed to irradiate in a concentrated manner.

3 with changing the angle with respect to the lens stack type 10
Since the active energy rays are evenly radiated from the direction,
Cancel the direction of the polymerization reaction of active energy rays,
Uniform gelation can be achieved in the pre-curing step, and the occurrence of aberrations and striae-like defects can be suppressed.

On the other hand, in the second aspect of the present invention, active energy rays are simultaneously irradiated from each of a plurality of linear irradiation sources having an intersecting angle in a direction parallel to the diametrical direction of the lens superimposing mold 10 for precuring. Is.

The linear irradiation sources 40 having crossing angles with each other may be arranged on both sides of the lens superimposing mold 10, or the linear irradiation sources having crossing angles with each other may be arranged on one of the lens superimposing molds. .

An example of such a pre-curing step is shown in FIG. FIG. 3A is a conceptual diagram showing the positional relationship between the lens-overlapping type vertical section and the linear irradiation source, and FIG. 3B is a lens polymerization showing the positional relationship between the linear irradiation source and the lens overlapping type. It is a conceptual diagram of the central axis direction of a mold.

In the pre-curing step shown in FIG. 3, active energy rays having different directions are simultaneously irradiated from both surface sides of the lens polymerization mold 10. As the linear irradiation source 40, the same one as in the first embodiment can be used.

In FIG. 3, a first linear irradiation source 40a is provided on both sides of the lens-molding mold 10 along the diameter direction of the lens-molding mold.
And the second linear irradiation source 40b are arranged, and the first linear irradiation source 40a and the second linear irradiation source 40b are oriented in directions orthogonal to each other. First linear irradiation source 40a
The first active energy ray emitted from the second linear irradiation source 40b and the second active energy ray emitted from the second linear irradiation source 40b are respectively reflected by the reflection plate 41.
Lens stacking type 10 substantially parallel to and perpendicular to each other
It is designed to be irradiated intensively.

As shown in FIG. 3, the lens superimposing mold 10 with the hole 131 through which the injection needle is placed is arranged between the first linear irradiation source 40a and the second linear irradiation source 40b, and the first linear irradiation source 40a is arranged. The linear irradiation source 40a and the second linear irradiation source 40b are simultaneously irradiated.
The irradiation time and the irradiation amount may be the same as in the usual pre-curing step.

In FIG. 3, the first linear irradiation source 40a and the second linear irradiation source 40b are arranged on both sides of the lens superposition type 10, but these first linear irradiation source 40a and The two-line irradiation source 40b may be arranged on either side of the convex surface forming glass mold 11 or the concave surface forming glass mold 12. Further, although the first linear irradiation source 40a faces the horizontal direction and the second linear irradiation source 40b faces the vertical direction,
It may be in a state in which they are inclined at an angle of 45 ° while maintaining the mutual orthogonality.

Further, in FIG. 3, the first linear irradiation source 40a and the second linear irradiation source 40b are arranged so as to cross each other on the central axis of the lens superimposing mold 10. The relative arrangement of the irradiation source 40a and the second linear irradiation source 40b is not limited to this. For example, as shown in FIG. 4, the linear irradiation sources 40a in the horizontal direction and the linear irradiation sources 40b in the vertical direction may be arranged in a grid pattern. In this case, one side of the lens stacking mold 10 has a horizontal linear irradiation source 40a.
It is needless to say that the linear linear irradiation source 40b can be arranged on the other side of the lens superimposing mold 10 by arranging. Also,
Not limited to the horizontal direction and the vertical direction, a plurality of linear irradiation sources 40 whose crossing angles are changed may be arranged.

In the pre-curing step shown in FIG. 3, by irradiating the first active energy ray and the second active energy ray in directions substantially orthogonal to each other at the same time, the directionality of the active energy ray is suppressed and the pre-curing is performed. A uniform gelation can be achieved in the process, and it is possible to manufacture a high-quality plastic lens in which the occurrence of aberrations and striae-like defects whose power varies depending on the site is suppressed.

After the pre-curing step, as shown in FIG. 5 (d), the lens polymerization mold 10 is carried into an irradiation furnace 50 capable of irradiating active energy rays, for example, from above and below, and pre-polymerized to obtain a plastic lens composition. A main curing step is completed to complete the polymerization of. In this case, thermal polymerization may be used together.

In the main curing step, the directionality of the active energy rays does not affect the quality as much as in the pre-curing step, but the irradiation furnace used is such that the lens polymerization mold is rotated.
Alternatively, it is preferable to arrange the upper and lower linear irradiation sources in directions orthogonal to each other, or to arrange the linear irradiation sources orthogonal to each other in the upper and lower directions so as to cancel the directionality of the active energy rays.

After the main curing step, the adhesive tape 13 is peeled off,
The glass molds 11 and 12 can be demolded to obtain a plastic lens.

The plastic lens obtained by the method of the present invention can be subjected to a treatment such as a hard coating treatment, a non-reflection coating treatment, a dyeing treatment or the like on one side or both sides, if necessary.

As the plastic lens composition that can be used in the method for producing a plastic lens of the present invention, any active energy ray-curable composition can be used. Particularly, it is particularly effective for a plastic lens composition having a slow gelation rate in the pre-curing step. Examples of such a plastic lens composition include a plastic lens composition containing an ultraviolet absorber and a photopolymerization initiator having an absorption property in the visible light region.

A composition for a plastic lens containing such an ultraviolet absorber and a photopolymerization initiator having an absorption property in the visible light region has an ultraviolet ray because the photopolymerization initiator undergoes radical decomposition by light in the visible light region. Even if it contains an absorber, it is polymerized by irradiating it with ultraviolet rays containing visible light, and it cures in a short polymerization time like ordinary UV-curing plastic lenses. Is a suitable production method.

However, probably because the energy of light in the visible light region is weak, the gelling time in pre-curing is slightly longer than usual. For example, in the case of a plastic lens composition containing no ultraviolet absorber, the pre-curing time is about 2 seconds for the finish lens and about 8 seconds for the semi-finished lens, but it contains the ultraviolet absorber and polymerizes in the visible light region. In the case of the plastic lens composition, the finish lens has a time of about 5 seconds and the semi-finished lens has a time of about 8 seconds, and the finish lens has a slightly longer pre-curing time. Therefore, the influence of the directionality of ultraviolet rays is seen to be somewhat remarkable, and it is effective to apply the method for producing a plastic lens of the present invention.

Hereinafter, the composition for a plastic lens containing an ultraviolet absorber and a photopolymerization initiator having an absorption characteristic in the visible light region will be described.

In such a plastic lens composition, 100 parts by weight of the raw material monomer and 0.
It is preferable to contain 1 to 5 parts by weight and 0.0005 to 5 parts by weight of a photopolymerization initiator having absorption characteristics in the visible light region.

Any raw material monomer can be used as long as it can be photopolymerized, and is not limited. The raw material monomer has a monofunctional or polyfunctional reactive group, and is, for example, an acrylate or methacrylate of an aliphatic, alicyclic, or aromatic alcohol, urethane acrylate, urethane methacrylate, epoxy acrylate, epoxy methacrylate, polyester acrylate, polyester. It is possible to use a compound having one or more radically polymerizable double bonds in the molecule such as methacrylate.

For example, Japanese Unexamined Patent Publication No. 8-176243,
JP-A-11-152317 and JP-A-11-158.
229, JP-A-11-174201, JP-A-11-174202, and JP-A-11-17420.
Raw material monomers described in Japanese Patent Publication No. 3 and the like can be used. Specific examples of the raw material monomers are shown below.

(A) Epoxy dimethacrylate obtained by reacting bisphenol A diglycidyl ether with methacrylic acid, epoxy diacrylate obtained by reacting tetrabromobisphenol A diglycidyl ether with acrylic acid, bisphenol F Epoxy poly (meth) acrylate having two or more (meth) acryloyloxy groups in one molecule, represented by epoxy dimethacrylate obtained by reacting diglycidyl ether and methacrylic acid.

(B) Polybutylene glycol di (meth) acrylate represented by nonabutylene glycol dimethacrylate and dodecabutylene glycol dimethacrylate.

(C) Phenyl methacrylate, benzyl methacrylate, phenyl ethyl methacrylate, o-
Biphenyl methacrylate, nonaethylene glycol dimethacrylate, 2,2-bis (4-methacryloyloxyethoxyphenyl) propane, 2,2-bis (4-
Methacryloyloxydiethoxyphenyl) propane,
2,2-bis (4-acryloyloxydiethoxyphenyl) propane, 2-phenyl-2- (4-methacryloyloxyethoxyphenyl) propane, 2-phenyl-2- (4-acryloyloxyethoxyphenyl) propane, phenoxyethyl A (meth) acrylate compound having at least one methacryloyl group or acryloyl group in the molecule represented by acrylate.

(D) Isophorone diisocyanate and 2-
Urethane dimethacrylate obtained by reacting hydroxypropyl methacrylate, urethane dimethacrylate obtained by reacting methylenebis (4-cyclohexylisocyanate) with 2-hydroxyethyl methacrylate, and xylylene diisocyanate with 2-hydroxyethyl methacrylate Urethane polymethacrylate having two or more (meth) acryloyloxy groups in the molecule represented by urethane dimethacrylate obtained by reacting urethane dimethacrylate, 2-hydroxypropyl methacrylate, and m-xylylene diisocyanate obtained by (Meth) acrylate.

(E) Tris (2-hydroxyethyl) isocyanuric acid tri (meth) acrylic acid ester, tris (2-hydroxyethyl) isocyanuric acid di (meth) acrylic acid ester, etc. isocyanuric acid (meth)
Acrylate compound.

(F) A low-viscosity (meth) acrylate monomer typified by isobornyl methacrylate, nonaethylene glycol dimethacrylate, and 1,6-hexamethylene glycol dimethacrylate.

(G) A mixture of 2- (4-vinylbenzylthio) ethanol and 2- (3-vinylbenzylthio) ethanol, 2- (4-vinylbenzylthio) isopropanol and 2- (3-vinylbenzylthio). ) Mixtures of isopropanol, 2- (4-vinylbenzylthio) butanol and 2- (3-vinylbenzylthio)
An aromatic vinyl compound containing at least one hydroxyl group and a sulfur atom, represented by a mixture of butanol, isocyanatoethyl (meth) acrylate, m-xylylene diisocyanate, m-tetramethylxylylene diisocyanate, and isophorone diisocyanate. , Tris (isocyanatohexyl) isocyanurate, bis (4,4′-isocyanatocyclohexyl) methane,
1,3-bis (isocyanatomethyl) cyclohexane,
A sulfur-containing urethane-vinyl compound obtained by reacting with an isocyanate compound represented by bis (4,4′-isocyanatophenyl) methane.

(H) Containing a styryl group represented by o-bis (4-vinylbenzylthioethyl) phthalate, bis (4-vinylbenzylthioethyl) succinate and m-bis (4-vinylbenzylthioethyl) phthalate. Sulfur aromatic compounds.

(I) Hydroxyl-containing (meth) acrylate compounds such as 2-hydroxyethyl methacrylate and 2-hydroxyethyl methacrylate, and 4,4'-bis (isocyanatoethylthiomethyl) phenyl sulfide and 4,4'-bis (Isocyanatoethylthioethylidene)
A bisphenylthioether group-containing urethane (meth) acrylate compound obtained by reacting with a diisocyanate compound having a bisphenylthioether group such as phenyl sulfide.

(J) 4,4'-bis (methacryloyloxyethylidene) phenyl sulfide, 4,4'-bis (methacryloylethoxythiomethylene) phenyl sulfide, 4,4'-bis (methacryloylethoxythioethylidene) phenyl sulfide, etc. Bisphenyl thioether group-containing di (meth) acrylate compound.

(K) A phenyl group represented by p-bis (β- (meth) acryloyloxyethylthio) xylylene and m-bis (β- (meth) acryloyloxyethylthio) xylylene, a thioether group and an acryloyl group. A sulfur-containing di (meth) acrylate compound to which a group having is bonded.

The composition can be constituted by appropriately selecting from these groups. For example, (A) + (B) +
(C) + (D), (A) + (B) + (C) + (E) +
(F), (G) + (K) + (C), (H) + (K) +
(C), (I) + (K) + (C), (J) + (K) +
The combination of (C) can be illustrated.

As the ultraviolet absorber, any ultraviolet absorber can be used as long as it is excellent in compatibility with raw material monomers. Examples thereof include benzophenone type, benzotriazole type, phenyl salicylate type, triazine type, Examples thereof include nickel salt type. Among them, the benzotriazole type is preferable because it has good solubility in the raw material monomer, high ultraviolet absorption ability, and has a feature that the color of the compound alone is pale or white and the lens is difficult to be colored.

Examples of the benzotriazole type ultraviolet absorber include 2- (2-hydroxy-5-methylphenyl) -2H-benzotriazole, 2- (2-hydroxy-5-tert-butylphenyl) benzotriazole, 2- (2-Hydroxy-3,5-di.tert-butylphenyl) benzotriazole, 5-chloro-2-
(3,5-Di-tert-butyl-2-hydroxyphenyl) -2H-benzotriazole, 2- (3-ter
t-butyl-2-hydroxy-5-methylphenyl)-
5-chloro-2H-benzotriazole, 2- (3,5
-Di-tert-pentyl-2-hydroxyphenyl)
-2H-benzotriazole, 2- (3,5-di-te
rt-Butyl-2-hydroxyphenyl) -2H-benzotriazole, 2- (2H-benzotriazole-2)
-Yl) -4-methyl- (3,4,5,6-tetrahydrophthalimidylmethyl) phenol, 2- (2-hydroxy-5-tert-octylphenyl) -2H-benzotriazole, 1.6-bis (4-benzoyl-3
-Hydroxyphenoxy) -hexane, 1,4-bis (4-benzoyl-4-octylphenyl) -2H-benzotriazole, 2- (2-hydroxy-4-octyloxyphenyl) -2H-benzotriazole and the like are exemplified. be able to. Further, a reactive ultraviolet absorber having a polymerizable functional group such as a (meth) acryloyloxy group, for example, 2- (2-hydroxy-5-methacryloxyethylphenyl) -2H-benzotriazole can also be used.

The blending amount of the ultraviolet absorber is an amount sufficient to allow the plastic lens to sufficiently absorb ultraviolet rays of 400 nm or less, and specifically, 0.1 to 5 parts by weight with respect to 100 parts by weight of the raw material monomer. , Preferably 0.2 to 3 parts by weight. If the amount of the ultraviolet absorber blended is too small, it is not possible to sufficiently suppress the transmission of ultraviolet rays and it is impossible to protect the eyes from ultraviolet rays. On the other hand, if the blending amount of the ultraviolet absorber is too large, it will be difficult to dissolve it in the raw material monomer, and the ultraviolet absorber will be deposited on the surface of the plastic lens during molding, or the adhesiveness with the glass mold will be reduced, and the polymerization reaction However, there is an inconvenience that it is blocked. The ultraviolet-absorbing plastic lens thus obtained has a spectral transmittance of 10% or less at 400 nm in a thickness of 2 mm after curing.

The photopolymerization initiator needs to have absorption characteristics in the visible light region of 400 nm or more. Examples of such a photopolymerization initiator include bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide (BAPO1) and bis (2,2
4,6-Trimethylbenzoyl) -phenylphosphine oxide (BAPO2) can be mentioned. B
APO1 and BAPO2 are 400 to 440n in the visible light range
It has absorption characteristics in the wavelength range of m and is suitable for use in combination with an ultraviolet absorber. These compounds have in common that they have a bisacylphosphine oxide structure. The former BAPO1 is not supplied as a single item.
And 2-hydroxy-2-methyl-1-phenyl-propan-1-one in a 1: 3 mixture (Ciba Specialty Chemicals, trade name Irgacure 1700),
A 1: 3 mixture of BAPO1 and 1-hydroxy-cyclohexyl-phenyl-ketone (Ciba Specialty Chemicals, trade name Irgacure 1800), B
A 1: 1 mixture of APO1 and 1-hydroxy-cyclohexyl-phenyl-ketone (Ciba Specialty.
It is commercially available under the trade name Irgacure 1850) manufactured by Chemicals. The latter BAPO2 is supplied as a single item under the trade name Irgacure 819 manufactured by Ciba Specialty Chemicals. In addition, α-aminoalkylphenone-based 2-benzyl-2-dimethylamino-1-
(4-morpholinophenyl) -butanone-1 (Ciba
Specialty Chemicals, trade name Irgacure 369), titanocene-based bis (η ⁵ -2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrol-1-yl) ) -Phenyl) titanium (manufactured by Ciba Specialty Chemicals, trade name Irgacure 784) can also be used.

The compounding amount of the photopolymerization initiator is the amount of the raw material monomer 1.
The amount is 0.0005 to 5 parts by weight, preferably 0.01 to 2 parts by weight, based on 00 parts by weight. If the compounding amount of the photopolymerization initiator is too small, it may not be possible to sufficiently polymerize, while if it is too large, the lens may be colored.

Further, the mercury lamp used for irradiation of active energy rays at the time of photopolymerization has a spectral distribution not only in the ultraviolet light region but also in the visible light region.
Even if all the ultraviolet rays having a wavelength of 00 nm or less are absorbed by the ultraviolet absorber, the photopolymerization initiator having the absorption property in the visible light region can be radically decomposed in the visible light region to cause polymerization. Among mercury lamps, metal halide lamps and ultra-high pressure mercury lamps have a strong distribution in the visible light region, and thus can be used more preferably than mercury short arc lamps and high pressure mercury lamps.

Since such a composition for an ultraviolet absorbing plastic lens uses a photopolymerization initiator and an ultraviolet absorber having an absorption property in the visible light region, the obtained plastic lens may be slightly colored. . In this case, coloring can be prevented by adding a bluing agent.

In addition to the above-mentioned components, thermal polymerization is used in combination with the ultraviolet absorbing plastic lens composition,
A thermal polymerization initiator such as an organic peroxide or an azo compound can be used in combination. In addition, other antioxidants, pigments,
An antistatic agent, an internal mold release agent, etc. can be blended.

[0085]

EXAMPLES Example 1 (1) Preparation of Composition 40 g of epoxydimethacrylate obtained by reacting bisphenol A diglycidyl ether with methacrylic acid as the component (A) and nonabutylene as the component (B). 20 g of glycol dimethacrylate, 25 g of benzyl methacrylate as the component (C), 15 g of urethane dimethacrylate obtained by reacting isophorone diisocyanate and 2-hydroxypropyl methacrylate as the component (D), and 2- (3 as an ultraviolet absorber. , 5-
Di-tert-butyl-2-hydroxyphenyl) -2
H-benzotriazole 1.0 g, t-butyl peroxyisobutyrate 0.1 g as a thermal polymerization initiator, Irgacure 1850 0.08 g as a photopolymerization initiator, and triethyl phosphite 0.2 g as an antioxidant are mixed. After stirring well at room temperature, reduce the pressure to 50 mmHg and
Degas for 0 minutes. (2) Production of lens polymerization type and injection of resin with an index of refraction of 1.55: + 6.00D
Using two glass molds (having a mold diameter of 70 mm) for the convex surface and the concave surface, which were obtained, were wrapped around with a pressure-sensitive adhesive tape obtained by coating a polyethylene terephthalate film with a silicone-based pressure-sensitive adhesive to prepare a lens polymerization type. . The composition prepared in (1) was injected with an injection needle. After the injection, the injection site was not sealed. (3) Pre-curing lamp type: metal halide lamp, emission length 10 inches,
Lamp input 3 kW Lamp illuminance: 140 mW / cm ² (measured at the center of the molding die) How to apply light during pre-curing: 2 from the convex side of the lens polymerization type
Irradiated twice. In the first preliminary curing, irradiation was performed with the injection site facing upward for 2 seconds, and in the second preliminary curing, the injection site was rotated by 90 degrees and irradiation was performed for another 3 seconds. (4) Main curing Main curing carry-in condition: 0.5 m / min Main curing condition: Rotate at a speed of 2 rpm under the lamp for 250 seconds, Lamp type: Same as pre-curing lamp illuminance: 100 mW / cm ² on convex side, concave surface Side 140
mW / cm ² (measured at the center of the mold directly under the lamp) Atmosphere temperature during main curing Actual measurement: 120 ° C. After that, the plastic lens was removed from the mold, and 13
Annealing was performed by heating at 0 ° C. for 2 hours. (5) Obtained lens evaluation diopter measuring instrument: lens meter PL-2 manufactured by Nikon Corp. The longitudinal diopter and diopter diopter at the center of the lens were measured, and the absolute value of the difference was defined as the aberration amount. Visual appearance Visually evaluates optical defects (fluctuations) through the transmitted light of a fluorescent lamp. When there was no optical defect, it was evaluated as ○, and when there was, it was evaluated as ×. This optical defect indicates a phenomenon in which many fine scratch-like lines are visible near the lens surface when the lens is seen through a fluorescent lamp. Evaluation of Internal Distortion Two polarizing plates are made orthogonal to each other, and light from a fluorescent lamp is illuminated from below.
A lens was inserted between the polarizing plates, and the internal distortion (distortion in the traveling direction) generated by the light inserted from the tape while the conveyor was being carried in was evaluated. ○ indicates that there is no internal strain, and × indicates that there is internal strain.

The evaluation results are shown in Table 1.

Example 2 (1) Preparation of Composition The same composition for plastic lenses as in Example 1 was prepared. (2) Preparation and injection of lens polymerization type The same procedure as in Example 1 was performed. (3) Pre-curing lamp type: the same as in Example 1. Lamp illuminance: 100 mW / cm ² (measured at the center of the molding die) Pre-curing light application: 3 times from the convex side. Irradiation was carried out for 2 seconds with the injection site facing upwards, 120 seconds for the injection site for 2 seconds, and 120 degrees for rotation (240 degrees from the initial position) for 2 seconds. (4) Main curing Main curing carrying-in conditions: the same as in Example 1. Main curing condition: Stop immediately below the lamp for 250 seconds, lamp type: same as in Example 1. Lamp illuminance: same as in Example 1. Actual temperature measurement during main curing: same as in Example 1. After this, remove the plastic lens from the mold,
Annealing was performed by heating at 0 ° C. for 2 hours. (5) Evaluation of the Obtained Lens Evaluation was performed in the same manner as in Example 1. The results are shown in Table 1.

Example 3 (1) Preparation of Composition The same composition for plastic lenses as in Example 1 was prepared. (2) Preparation and injection of lens polymerization type The same procedure as in Example 1 was performed. (3) Pre-curing lamp type: the same as in Example 1. Lamp illuminance: same as in Example 1. How to apply light in pre-curing: First, irradiation was performed from the convex surface side, irradiation was performed with the injection site facing up for 2 seconds, then irradiation was performed from the concave surface side, and the injection site was rotated by 90 ° and irradiated for 2 seconds. (4) Main curing Same as in Example 1. Then, the plastic lens was removed from the mold and heated at 130 ° C. for 2 hours for annealing treatment. (5) Evaluation of the obtained lens The evaluation was performed in the same manner as in Example 1.

Example 4 (1) Preparation of Composition As a component (G), a mixture of 2- (4-vinylbenzylthio) ethanol and 2- (3-vinylbenzylthio) ethanol and m-xylylene diisocyanate. The sulfur-containing urethane-vinyl compound obtained by reacting with
g, 35 g of p-bis (β-methacryloyloxyethylthio) xylylene as the component (K), 15 g of 2,2-bis (4-acryloyloxydiethoxyphenyl) propane as the component (C), and as the component (C) 10 g of benzyl methacrylate, 0.5 g of triethylphosphite as an antioxidant, and bis (1,
0.5 g of 2,2,6,6-pentamethyl-4-puperidyl) sebacate and 2- (3,5-
Di-tert-butyl-2-hydroxyphenyl) -2
After adding 0.5 g of H-benzotriazole, 0.3 g of Irgacure 1700 as a photopolymerization initiator and 0.1 g of t-butylperoxyisobutyrate as a thermal polymerization initiator, and mixing, after stirring well at room temperature The pressure was reduced to 50 mmHg and degassed for 10 minutes. (2) Preparation of lens polymerization type and injection molding resin with a refractive index of 1.60 + 6.00D
Using two glass molds (having a mold diameter of 70 mm) for the convex surface and the concave surface obtained in (1), the periphery thereof was wrapped with an adhesive tape obtained by coating a polyethylene terephthalate film with a silicone-based adhesive to prepare a lens polymerization type. The composition prepared in (1) was injected into this lens polymerization type with an injection needle.
After the injection, the injection site was not sealed. (3) Pre-curing lamp type: the same as in Example 1. Lamp illuminance: same as in Example 1. How to apply light during pre-curing: Irradiate from the convex side. Irradiation was continued for 5 seconds with the injection site facing up, and the injection site was rotated 90 degrees for an additional 5 seconds. (4) Main curing Main curing carry-in condition: 0.5 m / min Main curing condition: Rotate at a speed of 2 rpm directly under the lamp for 250 seconds, Lamp type: Same as pre-curing lamp illuminance: Convex side 60 mW / cm ² , concave surface 90mW on the side
/ Cm ² (measured at the center of the mold directly under the lamp) Actual temperature measurement during main curing: 80 ° C. After that, the plastic lens was removed from the mold, and 13
Annealing was performed by heating at 0 ° C. for 2 hours. (6) Evaluation of Obtained Lens Evaluation was performed in the same manner as in Example 1.

Comparative Example 1 (1) Preparation of Composition The same composition for plastic lenses as in Example 1 was prepared. (2) Preparation and injection of lens polymerization type The same procedure as in Example 1 was performed. (3) Pre-curing lamp type: the same as in Example 1. Lamp illuminance: same as in Example 1. How to apply light during pre-curing: Irradiate from the convex side. Irradiation was performed for 2 seconds with the injection site facing up. (4) Main curing Main curing was performed under the same conditions as in Example 1. Then, the plastic lens was removed from the mold and heated at 130 ° C. for 2 hours for annealing treatment. (5) Evaluation of the Obtained Lens Evaluation was performed in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 2 (1) Preparation of Composition The same composition for plastic lenses as in Example 1 was prepared. (2) Preparation and injection of lens polymerization type The same procedure as in Example 1 was performed. (3) Pre-curing lamp type: the same as in Example 1. Lamp illuminance: same as in Example 1. How to apply light during pre-curing: Irradiate from the convex side. 5 seconds with the injection point up. (4) Main curing Main curing was performed under the same conditions as in Example 1. Then, the plastic lens was removed from the mold and heated at 130 ° C. for 2 hours for annealing treatment. (5) Evaluation of the Obtained Lens Evaluation was performed in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 3 (1) Preparation of Composition The same composition for plastic lenses as in Example 4 was prepared. (2) Preparation and injection of lens polymerization type The same procedure as in Example 1 was performed. (3) Pre-curing lamp type: The same as in Example 1. Lamp illuminance: same as in Example 1. How to apply light during pre-curing: Irradiate from the convex side. 10 seconds with the injection point up. (4) Main curing Main curing was performed under the same conditions as in Example 4. Then, the plastic lens was removed from the mold and heated at 130 ° C. for 2 hours for annealing treatment. (5) Evaluation of the Obtained Lens Evaluation was performed in the same manner as in Example 1. The results are shown in Table 1.

[0093]

[Table 1]

In Comparative Example 1, since the irradiation time in the pre-curing was short, the pre-polymerization was not sufficient and the main curing was distorted. In Comparative Example 2 and Comparative Example 3, the directionality of ultraviolet rays in pre-curing appears, the amount of aberration is large, and fluctuations (striated defects) also occur.

On the other hand, it is recognized that in the examples in which the pre-curing of the present invention is performed, a high quality plastic lens having a small amount of aberration and no fluctuation is obtained.

[0096]

According to the method for producing a plastic lens of the present invention, since a homogeneous prepolymerization can be carried out in the precuring step, a high quality plastic lens can be produced.

[Brief description of drawings]

FIG. 1 shows a relative angle of 90 degrees between a lens superposition type and a linear irradiation source.
It is a conceptual diagram explaining the precure process which changes ° and irradiates an active energy ray twice.

FIG. 2 shows the relative angle between the lens superposition type and the linear irradiation source as 12
It is a conceptual diagram explaining the preliminary hardening process which changes 0 degree and irradiates an active energy ray 3 times in total.

FIG. 3 is a conceptual diagram illustrating a pre-curing step of simultaneously irradiating active energy rays from each of two linear irradiation sources having 90 ° crossing angles.

FIG. 4 is a conceptual diagram showing linear irradiation sources arranged in a grid pattern.

FIG. 5 is a flowchart illustrating a manufacturing process of a plastic lens including a pre-curing process.

[Explanation of symbols]

10 Lens superposition type 11 Glass mold for forming convex surface 12 Glass mold for forming concave surface 13 Adhesive tape 131 Hole opened by injection needle 30 Composition for plastic lens 40 linear irradiation source 41 Reflector

Claims (5)

[Claims] 1. A pre-curing step of pre-polymerizing the plastic lens composition by irradiating the composition for plastic lenses filled in the lens polymerization type with active energy rays from one side or both sides of the lens polymerization type, In a method for producing a plastic lens, which comprises a pre-polymerization and a main curing step of irradiating the composition for a plastic lens with active energy rays and / or heating to complete the polymerization, the pre-curing step comprises A method for producing a plastic lens, which comprises sequentially irradiating active energy rays by changing a relative angle between the lens polymerization type and a linear irradiation source that emits active energy rays in a direction parallel to a diameter direction. 2. A pre-curing step of pre-polymerizing the plastic lens composition by irradiating the composition for plastic lenses filled in the lens polymerization type with active energy rays from one side or both sides of the lens polymerization type, In the method for producing a plastic lens, which comprises a main curing step of irradiating an active energy ray and / or a heat treatment to the pre-polymerized composition for a plastic lens to complete the polymerization, wherein the pre-curing step is the lens polymerization type A method for producing a plastic lens, characterized in that active energy rays are simultaneously irradiated from each of a plurality of linear irradiation sources having an intersecting angle in a direction parallel to the diametrical direction. 3. The method of manufacturing a plastic lens according to claim 1 or 2, wherein the relative angle between the lens superposition type and the linear irradiation source or the intersecting angle is an angle obtained by substantially dividing 180 ° or 360 °. A method of manufacturing a plastic lens, characterized by being present. 4. The method of manufacturing a plastic lens according to claim 2, wherein the plurality of linear irradiation sources are arranged on both sides of the lens polymerization type. 5. The method for producing a plastic lens according to claim 1, wherein the composition for a plastic lens contains 1 of a raw material monomer.
00 parts by weight, 0.1 to 5 parts by weight of an ultraviolet absorber, and 0.0005 to 0.005 parts of a photopolymerization initiator having absorption characteristics in the visible light region.
A method for producing a plastic lens, which comprises 5 parts by weight.