KR101145947B1 - Light-blocking member for optical instrument - Google Patents

Abstract

Provided is a light blocking member for an optical device having gloss removal properties and maintaining physical properties of a light shielding film such as light shielding properties and sliding properties.

The light shielding member 1 for optical apparatuses of this invention is comprised from the base material 2 used as a synthetic resin film, and the light shielding film 3 formed in at least one surface of this base material 2. This light shielding film 3 shall contain binder resin and carbon black 31, the lubricating agent 32 of a particle | grain, and the specific fine particle 33. The specific fine particles 33 are organic fine particles or inorganic fine particles having an oil absorption amount of 250 (g / 100 g) or more, and among them, silica is particularly suitably used.

Light blocking member for optics, carbon black, lubricant, light blocking, sliding

Description

Light-shielding member for optical instruments {Light-blocking member for optical instrument}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to light shielding members suitably used as shutters and diaphragm members of optical devices such as high performance single lens reflex cameras, compact cameras, compact cameras, video cameras, cellular phones, and projectors.

In recent years, with the demand for miniaturization and weight reduction of high-performance single-lens reflex cameras, compact cameras, video cameras, and the like, shutters and diaphragm members of optical devices formed of metal materials have been replaced by plastic materials.

As a diaphragm of such a plastic material, the light-shielding film which provided the light shielding film containing carbon black, a lubricating agent, and microparticles | fine-particles in the base film is known (patent document 1).

Patent Document 1: Japanese Patent Application Laid-Open No. 9-274218

DISCLOSURE OF INVENTION

Problems to be Solved by the Invention

However, in the light-shielding film as described above, since a large amount of fine particles must be contained in the light-shielding film to impart delustering properties, the content rate of carbon black and lubricant in the light-shielding film is lowered, and as a result, There is a problem that sliding properties are not sufficiently exhibited.

In order to solve the above-mentioned problem, the light-shielding member which has glossiness removal property and maintained the physical property of the light-shielding film, such as light-shielding property and sliding property, is urgently desired.

Means to solve the problem

MEANS TO SOLVE THE PROBLEM As a result of earnestly researching in order to solve the above-mentioned subject, the present inventors found that it can provide glossiness removal property even if it uses a small amount of specific microparticles | fine-particles.

That is, although the reason is not clear, by using fine particles having a high oil absorption amount, glossiness removal property can be obtained in a small amount, and as a result, the content rate of carbon black and lubricant in the light shielding film can be increased, The inventors have found that the physical properties of the light shielding film can be maintained and the present invention has been reached.

The light shielding member for an optical device of the present invention comprises a substrate made of a synthetic resin film and a light shielding film formed on at least one side of the substrate, wherein the light shielding film is binder resin, carbon black, particulate lubricant and oil absorption amount of 250 (g / 100 g) or more. It is characterized by containing fine particles.

The light shielding member for an optical device of the present invention is characterized in that the content of the fine particles in the light shielding film is 3% by weight or less in the light shielding film.

The light shielding member for an optical device of the present invention is characterized in that the average particle diameter of the lubricant is larger than the average particle diameter of the fine particles.

Effects of the Invention

According to the present invention, by including specific fine particles in the light shielding film, that is, fine particles having oil absorption of 250 (g / 100 g) or more, glossiness removal property can be obtained in a small amount, so that the content rate of carbon black and lubricant in the light shielding film can be increased. It is possible to obtain a light shielding member for an optical device having gloss removal properties and retaining physical properties of the light shielding film such as light shielding properties and sliding properties. Therefore, such a light shielding member for optical devices can be suitably used for high performance single-lens reflex cameras, compact cameras, video cameras, mobile phones, projectors and the like.

Further, according to the present invention, by employing a lubricant whose average particle diameter is larger than the average particle size of the fine particles, the unevenness of the surface of the light shielding film can be complicated in the state capable of exhibiting the function of the lubricant, and even if the content of the fine particles is small, Better gloss removal can be realized.

Carrying out the invention  Best form for

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of the light shielding member for optical instruments of this invention is described.

As shown in FIG. 1, the light blocking member 1 for an optical device of the present invention is composed of a base material 2 made of a synthetic resin film and a light blocking film 3 formed on at least one surface thereof, and the light blocking film 3 is formed of a binder resin and carbon black. (31), particulate lubricant 32 and fine particles 33 having an oil absorption amount of 250 (g / 100g) or more.

Examples of the substrate used as the light shielding member for the optical device of the present invention include synthetic resin films such as polyester films, polyimide films, polystyrene films, and polycarbonate films. Among them, polyester films are suitably used. In particular, a biaxially stretched polyester film is particularly preferable in terms of excellent mechanical strength and dimensional stability. In addition, it is also possible to use a synthetic resin film containing not only transparent but also expanded polyester film, black pigments, such as carbon black, and another pigment. In this case, the above-mentioned base material can select an appropriate thing according to each use. For example, when used as a light shielding member, the light collected by a lens or the like is adversely affected in the synthetic resin film portion of the cross section of the member, so that when a high light shielding property is required, a synthetic resin film containing black pigment such as carbon black is used. In other cases, a transparent or foamed synthetic resin film can be used.

In the present invention, since sufficient light shielding properties as the light shielding member can be obtained by the light shielding film itself, when the black resin is contained in the synthetic resin film, the synthetic resin film is contained in such a degree that the optical density becomes about 3, that is, to the naked eye. Just do it. Therefore, since the black pigment is not contained in the synthetic resin film to the limit that the physical properties of the substrate are impaired as in the prior art, it can be obtained at low cost without changing the physical properties of the synthetic resin film.

Although the thickness of a base material changes with uses, it is generally preferable to set it as 25 micrometers-250 micrometers from a viewpoint of light weight, the strength as a light shielding member, rigidity, etc.

In addition, from the viewpoint of improving the adhesion to the light shielding film, the substrate may be subjected to anchor treatment or corona treatment as necessary.

Next, the light shielding film formed on at least one surface of the base material used as the light shielding member for optical devices of the present invention contains binder resin, carbon black, particulate lubricant, and fine particles having oil absorption of 250 (g / 100 g) or more.

As binder resin contained in a light shielding film, poly (meth) acrylic-acid resin, polyester resin, polyvinyl acetate resin, polyvinyl chloride, polyvinyl butyral resin, a cellulose resin, polystyrene / polybutadiene resin, a polyurethane resin, an alkyd resin , Acrylic resin, unsaturated polyester resin, epoxy ester resin, epoxy resin, epoxy acrylate resin, urethane acrylate resin, polyester acrylate resin, polyether acrylate resin, phenol resin, melamine resin, Thermoplastic resins or thermosetting resins, such as urea resin and diallyl phthalate type resin, are mentioned, It is also possible to use these 1 type, or in mixture of 2 or more types.

50 weight%-80 weight% are preferable in a light shielding film, and, as for the content rate of binder resin, it is more preferable to set it as 55 weight%-75 weight%. By setting it as 50 weight% or more in a light shielding film, it can prevent that the adhesiveness of a base material and a light shielding film falls, and by setting it as 80 weight% or less, it can prevent that the physical property of light shielding films, such as light shielding property, sliding property, glossiness removal property, falls. Can be.

Next, the carbon black contained in the light shielding film is used to color the binder resin in black to impart light shielding properties, to impart conductivity, and to prevent electrostatic charging.

In order to obtain sufficient light-shielding property, 1 micrometer or less is preferable and, as for the average particle diameter of carbon black, it is more preferable to set it as 0.5 micrometer or less.

5 weight%-20 weight% are preferable in a light shielding film, and, as for the content rate of carbon black, it is more preferable to set it as 10 weight%-20 weight%. By setting it as 5 weight% or more in a light shielding film, it can prevent that light-shielding property and electroconductivity fall, and by setting it as 20 weight% or less, adhesiveness and abrasion resistance improve, and also the fall of coating film strength and high cost Can be prevented.

Next, the particulate lubricant contained in the light shielding film is intended to improve the sliding property of the surface of the light shielding member, to reduce the frictional resistance during operation and to improve the scratch resistance of the surface when processed with a diaphragm member or the like. As such a solid, any organic or inorganic type can be used. For example, hydrocarbon type lubricants such as polyethylene wax and paraffin wax, fatty acid type lubricants such as stearic acid and 12-hydroxy stearic acid, oleic acid amide, Amide lubricants such as erucic acid amide, ester lubricants such as stearic acid monoglyceride, alcohol lubricants, solid lubricants such as metal soap, talc, molybdenum disulfide, silicone resin particles, and polytetrafluor Fluorine resin particles, such as ethylene wax, crosslinked polymethylmethacrylate particle, crosslinked polystyrene particle, etc. are mentioned, Especially organic thing is used preferably. Moreover, these 1 type, or 2 or more types can be mixed and used.

3 micrometers-20 micrometers are preferable, and, as for the average particle diameter of a lubricant, it is more preferable to set it as 5 micrometers-10 micrometers. It is because an unevenness | corrugation suitable for a surface is formed by setting it as such a range, and slidability can be obtained.

1, it is preferable to make the average particle diameter of the lubricant 32 larger than the average particle diameter of the microparticles | fine-particles 33. Moreover, as shown in FIG. By making the average particle diameter of the lubricant 32 larger than the average particle diameter of the fine particles 33, fine unevenness is formed by the fine particles on the unevenness of the surface formed by the lubricant, so that the reflection of incident light is reduced to obtain sufficient gloss removal property. This is because it can be obtained and also the slidability.

The content of the lubricant is preferably 5% by weight to 20% by weight in the light shielding film, and more preferably 10% by weight to 20% by weight. By setting it as 5 weight% or more in a light shielding film, an appropriate unevenness | corrugation is formed in a surface, and slidability can be obtained, and by setting it as 20 weight% or less, the relative content of carbon black can be made high and light-shielding property and electroconductivity are prevented from falling. can do.

Next, the fine particles contained in the light shielding film reduce the reflection of incident light by forming fine unevenness on the surface to lower the glossiness (mirror glossiness) of the surface, thereby improving glossiness removal when the light shielding member is used.

The fine particles are indispensable in order to impart gloss removability to the surface when the light shielding member is used, but the ratio of the fine particles to be contained in the light shielding film is limited as follows. First, when the content of the fine particles is increased without changing the ratio of the resin and the other components, the content of carbon black, lubricant, and the like decreases accordingly, resulting in a decrease in physical properties such as light shielding and sliding properties as the light shielding member. In order to maintain physical properties such as light shielding properties, when the content of the binder resin is decreased while the content of the binder resin is increased while the content of the carbon black and the lubricant in the light shielding film is increased, the adhesion between the substrate and the light shielding film is insufficient. The deterioration is normal. In other words, when fine particles having sufficient gloss removal properties are contained in the light shielding film, physical properties such as light shielding properties and sliding properties cannot be maintained or scratch resistance is poor.

In the present invention, unlike the fine particles used as a gloss remover in the conventional light-shielding member, by using specific fine particles, that is, fine particles having oil absorption of 250 (g / 100 g) or more, preferably fine particles having oil absorption of 300 (g / 100 g) or more The glossiness removal property of the surface was obtained in a small amount, and it became possible to increase the content rate of carbon black, a lubricating agent, etc. in a light shielding film. As a result, by using the fine particles described above, it is possible to obtain a remarkable effect, which has not been achieved in the past, that the light shielding film can be sufficiently exerted to exhibit physical properties such as light shielding properties and sliding properties.

In addition, in this specification, oil absorption amount is based on ISO787 / V-1968, and it is the amount (g) of oil required to wet-mix linseed oil to 100 g of fine particles, and to form a hard paste.

As such specific microparticles | fine-particles, any of organic type, such as crosslinked acrylic beads, and inorganic type, such as a silica, metasilicate, magnesium aluminate, and titanium oxide, can be used, but it is preferable that it is an inorganic type, Especially, a viewpoint of dispersibility of a microparticle, low cost, etc. Preference is given to using silica in the process. Moreover, it is also possible to use these 1 type or in mixture of 2 or more types.

1 micrometer-10 micrometers are preferable, and, as for the average particle diameter of microparticles | fine-particles, it is more preferable to set it as 1 micrometer-6 micrometers. It is because fine unevenness | corrugation is formed in the surface of a light shielding member by setting it as such a range, and glossiness removal property can be obtained.

1 weight%-10 weight% are preferable, and, as for the content rate of microparticles | fine-particles, it is more preferable to set it as 1 weight%-5 weight%. By setting it as 1 weight% or more in a light shielding film, the glossiness (mirror glossiness) of a surface can increase and glossiness removal property can be prevented from falling, and by setting it as 10 weight% or less, the particle | grains fall by sliding of a light shielding member generate | occur | produce. It is possible to prevent or reduce the sliding.

When especially high light-shielding property and sliding property are calculated | required, it is preferable to make content rate of microparticles | fine-particles into 3 weight% or less in a light shielding film further in the range mentioned above. Since the fine particles used in the present invention can obtain high gloss removal property even in a small amount as described above, by setting it as 3% by weight or less, sufficient gloss removal property can be obtained and the content of carbon black and lubricant is relatively increased. It becomes possible to make it possible to improve physical properties, such as light-shielding property and sliding property.

If the light shielding film of this invention does not impair the function of this invention, it can contain various additives, such as a flame retardant, an antibacterial agent, an antifungal agent, antioxidant, a plasticizer, a leveling agent, a flow regulator, an antifoamer, and a dispersing agent.

5 micrometers-30 micrometers are preferable, and, as for the thickness of a light shielding film, it is more preferable to set it as 5 micrometers-20 micrometers. By setting it as 5 micrometers or more, a pinhole etc. can be prevented from occurring in a light shielding film, and sufficient light-shielding property can be obtained. Moreover, by making it 30 micrometers or less, it can prevent that a crack arises in a light shielding film.

The light shielding member for an optical device of the present invention dips a coating liquid for a light shielding film containing the above-described binder resin, carbon black, particulate lubricant, and specific fine particles onto one or both surfaces of a substrate which is a synthetic resin film as described above. After coating and drying by conventionally well-known coating methods, such as a coat, a roll coat, a bar coat, a die coat, a blade coat, and an air knife coat, it can obtain by heating and pressurization etc. as needed. As a solvent of a coating liquid, water, an organic solvent, the mixture of water and an organic solvent, etc. can be used.

As described above, the light shielding member for an optical device of the present invention has a light shielding film configured as described above on at least one side of a substrate made of a synthetic resin film as described above, and thus has a gloss removal property, Since the physical properties of the light shielding film are maintained, it can be suitably used as a shutter and a diaphragm member of an optical device such as a high-performance single-lens reflex camera, a compact camera, a video camera, a mobile phone, a projector and the like.

Hereinafter, the present invention will be further described by way of examples. In addition, "part" and "%" are taken as a basis of weight unless there is particular notice.

1. Fabrication of light blocking member for optical equipment

[Examples 1 and 2 and Comparative Examples 1 to 6]

Using the black polyethylene terephthalate film (lumirror X30: Toray Corporation) of thickness 50micrometer as a base material, the coating liquid (a)-(h) for light-shielding films of the following prescriptions, respectively, was applied to both surfaces by the bar coat method. Was applied so that the thickness at the time of drying became 10 micrometers, and it dried and formed the light shielding films A-H, and the light-shielding member for optical instruments of Examples 1 and 2 and Comparative Examples 1-6 was produced. In addition, Table 1 shows content (part), such as the acryl polyol of the coating liquids (a)-(h) for light shielding films of the following prescription. In addition, the content rate (%) of acrylic polyol etc. of formed light shielding films A-H are shown in Table 2.

<Prescription of coating liquid (a)-(b) for light shielding film>

Acrylic polyol (50% solids) (part of Table 1)

(Accredit A804: Dainippon Inkoki Kagaku High School)

Isocyanate (75% solids) (part of Table 1)

(Burnock DN980: Dainippon Inky Kagaku High School)

Carbon black (part of table 1 mention)

(Barcan XC-72: Gyabottosa)

Activation (part of table 1 mention)

(Average particle size: 8.5 μm) (Serdust 3620: Hexto)

Particulates (silica) (particulates and parts listed in Table 1)

? Methyl ethyl ketone 60 parts

Toluene 40 parts

Fine particles P: TS100: Degussa, oil absorption 390 (g / 100 g), average particle size 4 ㎛

Microparticles | fine-particles Q: AZ-200: Doso-silica company, oil absorption amount 330 (g / 100g), average particle diameter 2.4 micrometers

Fine particle R: TK900: Degussa, oil absorption 90 (g / 100 g), average particle diameter 8 micrometers

Particles S: Silisia 730: Fuji silician Kagakusa, oil absorption 95 (g / 100 g), average particle size 4 ㎛

2. Evaluation

The physical properties of the light shielding members for optical devices obtained in Examples 1 and 2 and Comparative Examples 1 to 6 as described above were evaluated by the following method. Each result is shown in Table 3. However, about evaluation of the following (1) light-shielding property, the prescription of the said Example 1, 2 and Comparative Examples 1-6 on one surface of the 50-micrometer-thick transparent polyethylene terephthalate film (Lumirror T60: Toray Corporation) It carried out using the sample formed with the light shielding films A-H of 10 micrometers in thickness.

(1) evaluation of light shielding properties

The samples of Examples 1 and 2 and Comparative Examples 1 to 6 were measured for optical density using an optical densitometer (TD-904: Gretag Macbeth Co., Ltd.) based on JIS K7651: 1988 and exceeded 4.0. The thing of the density | concentration of an area | region was made into "(circle)", and the thing of 4.0 or less was made into "x". In addition, the measurement used the UV filter.

(2) evaluation of sliding

Based on JIS K7125: 1999, the light shielding members for optical devices obtained in Examples 1 and 2 and Comparative Examples 1 to 6 were subjected to static friction coefficients and copper under conditions of a load of 200 (g) and a speed of 100 (mm / min). The coefficient of friction (μk) was measured. The thing with a static friction coefficient of 0.35 or less "(circle)" and the thing of 0.35 or more were made into "x". In addition, "(circle)" and thing with 0.30 or more were made into "(circle)" that the dynamic friction coefficient (muk) is 0.30 or less. In addition, it was set as "?" That the shading film was shaved and became impossible to measure.

(3) Evaluation of gloss removal

The glossiness (mirror glossiness) (%) of the surface of the light shielding member for optical instruments obtained in Examples 1 and 2 and Comparative Examples 1 to 6 was measured based on JIS Z8741: 1997.

(4) Evaluation of conductivity

The surface resistivity (Ω) of the light shielding members for optical devices obtained in Examples 1 and 2 and Comparative Examples 1 to 6 was measured based on JIS K6911: 1995. That the surface resistivity is less than 1.0 × 10 ⁵ Ω or more "○", "△" to 1.0 × 10 ⁵ Ω or more is less than 1.0 × 10 ⁸ Ω, 1.0 × 10 ⁸ Ω was set to "×."

(5) Evaluation of adhesiveness

The light shielding members for optical instruments obtained in Examples 1 and 2 and Comparative Examples 1 to 6 were measured based on the checkerboard eye tape method in JIS K5400: 1990. "X" and the thing of less than 5% were made into "(circle)" that the area of the board | substrate eye part peeled 5% or more.

(6) evaluation of scratch resistance

Using the light-shielding member for optical apparatuses obtained in Examples 1 and 2 and Comparative Examples 1 to 6 as a camera diaphragm member, it was operated 1 million times to examine the presence or absence of abrasion and peeling of the coating film surface. ", And the thing where abrasion and peeling were recognized was made into" x ".

As is apparent from the results in Table 3, the light shielding members for optical devices obtained in Examples 1 and 2 have binder resins, carbon black, particulate lubricant and specific fine particles on both surfaces of the substrate, that is, oil absorption of 250 (g / 100 g) or more. Since the light-shielding film containing fine particles is formed, the glossiness removal property can be obtained with a small amount of fine particles. As a result, the light-removing properties of the light-shielding film such as light-shielding properties and sliding properties are maintained while the gloss-removing property is retained. This became excellent.

On the other hand, since the light shielding members for optical instruments obtained in Comparative Examples 1 and 2 contain fine particles having low oil absorption in the light shielding film at the same content as those used in Examples 1 and 2, the light shielding members for optical instruments of Examples 1 and 2 Compared to the gloss removal property was inferior.

In addition, since the light shielding members for optical devices obtained in Comparative Examples 3 and 4 contain a large amount of fine particles having a low oil absorption in order to impart gloss removal property, the content rate of carbon black and lubricant in the light shielding film is lowered, and Example 1 The light shielding property, the sliding property, and the electroconductivity were inferior to the light shielding member for optical devices of 2 and 2. Furthermore, since the content of the lubricant is low, appropriate irregularities are not formed on the surface, and the content of the carbon black is low. Therefore, even though the content of the fine particles is increased for the purpose of providing gloss removal property, Glossiness removal property was also inferior compared with Examples 1 and 2.

In addition, in order to maintain physical properties such as light shielding properties, the light shielding members for optical devices obtained in Comparative Examples 5 and 6 lower the content of binder resin while maintaining the content of carbon black and lubricant in the light shielding film, and a large amount of fine particles having low oil absorption. As a result, the adhesiveness of the base material and the light shielding film was insufficient, and the scratch resistance was inferior.

Brief description of the drawings

1 is a view showing one embodiment of a light blocking member for an optical device of the present invention.

Explanation of the sign

One… … Light blocking member for optical equipment

2… … materials

3 ... … Shading

31... … Binder Resin and Carbon Black

32... … Lubricant

33... … Particulate

Claims (7)

And a light shielding film formed on at least one surface of the base material, wherein the light shielding film contains binder resin, carbon black, particulate lubricant and fine particles having oil absorption of 250 (g / 100 g) or more, and the average of the lubricants. A light shielding member for an optical device, wherein a particle diameter is larger than an average particle diameter of the fine particles. The light blocking member for optical apparatus according to claim 1, wherein the average particle diameter of the lubricant is in the range of 3 to 20 m, and the average particle diameter of the fine particles is in the range of 1 to 10 m. The light blocking member for optical apparatus according to claim 1 or 2, wherein a content rate of the fine particles in the light shielding film is 3% by weight or less in the light shielding film. The light blocking member for optical apparatus according to claim 1, wherein the content rate of the carbon black, the lubricant, and the fine particles in the light shielding film is in the range of 5 to 20% by weight, 5 to 20% by weight, and 1 to 10% by weight, respectively. . The light blocking member for optical apparatus according to claim 4, wherein the content rate of the carbon black, the lubricant, and the fine particles in the light shielding film is in the range of 10 to 20% by weight, 10 to 20% by weight, and 1 to 5% by weight, respectively. . And a light shielding film formed on at least one surface of the base material, wherein the light shielding film contains binder resin, carbon black, particulate lubricant and fine particles having oil absorption of 250 (g / 100 g) or more. The light-shielding member for optical apparatuses characterized by the content rate of the said microparticles | fine-particles of being 3 weight% or less in a light shielding film. The light blocking member for optical apparatus according to claim 1 or 6, wherein the fine particles are silica.

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