JPH0525611A - Formation of reflection mirror made of synthetic resin - Google Patents

Abstract

PURPOSE:To produce the reflection mirror which is made of a synthetic resin and satisfies optical characteristics and durability by exposing a base plate to UV rays and gaseous ozone before the formation of the film for the reflection mirror. CONSTITUTION:The surface of the synthetic resin base plate 1 consisting of a polycarbonate resin is irradiated with the UV rays of 185nm wavelength for 30 to 120 seconds. After the base plate is pretreated by exposing the base plate to the ozone generated by the UV rays, the base plate is put into a vacuum chamber into which gaseous Ar is introduced at 3X10<-3> Torr under 5X10<-6> Torr vacuum degree. An Al film 2 is then formed at 60nm by a DC magnetron sputtering method of 200W throwing electric power. The reflection mirror having such rear surface has >=80% spectral reflectivity at 400 to 700m visible light region. The results of the test on adhesion after an initial adhesion test and environmental resistance test are good.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、合成樹脂製基板上に金
属膜のコーティングを施した反射鏡の作成方法に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a reflecting mirror in which a synthetic resin substrate is coated with a metal film.

【０００２】[0002]

【従来の技術】近年、レンズ等の光学部品に合成樹脂製
部品を用いる頻度が高くなっており、特にカメラ用、Ａ
Ｖ用として今後さらに要求が高くなると思われる合成樹
脂製部品の一つに表面反射鏡・裏面反射鏡などの反射鏡
がある。合成樹脂製部品には、ガラス製光学部品に比較
して複雑形状化，低コスト化および軽量化を図る事がで
き、プリズム形成などではガラス製のものよりも加工し
易いという利点も有している。2. Description of the Related Art Recently, synthetic resin parts are frequently used for optical parts such as lenses, especially for cameras,
One of the synthetic resin parts for which V is expected to be in high demand in the future is a reflector such as a front reflector and a back reflector. Compared to glass optical parts, synthetic resin parts can have a more complicated shape, lower cost, and lighter weight, and also have the advantage that they can be processed more easily than glass parts in prism formation. There is.

【０００３】ところで、合成樹脂製部品を反射鏡として
用いるためには、射出成形や切削等で合成樹脂を加工し
た後、任意の表面に表面鏡あるいは裏面鏡としてのコー
ティングが要求される。従来このコーティングにはガラ
スに用いるものと同様な真空蒸着法が用いられてきた。By the way, in order to use a synthetic resin part as a reflecting mirror, it is required to coat synthetic resin on an arbitrary surface as a front surface mirror or a rear surface mirror after processing the synthetic resin by injection molding or cutting. Conventionally, the same vacuum deposition method as that used for glass has been used for this coating.

【０００４】しかしながら、合成樹脂製光学部品の場
合、ガラスに用いるものと同様の蒸着材料，膜構成およ
び成膜方法でコーティングを行うと、成膜後にマイクロ
クラックが発生したり、基板に対する膜の密着強度が不
十分であったり、あるいは蒸着後には異常がなくとも対
環境試験後にマイクロクラックを発生してしまった。However, in the case of synthetic resin optical parts, when coating is performed with the same vapor deposition material, film structure and film forming method as those used for glass, microcracks are generated after film formation and the film adheres to the substrate. The strength was insufficient, or even if there was no abnormality after vapor deposition, microcracks were generated after the environmental test.

【０００５】因って、上記欠点を解決する方法として以
下の様な発明が提案されている。例えば、特開平２−６
６１５７号公報記載の発明においては、基板側から第１
層目に物理的膜厚ｄ＝１００ｎｍのＣｅＦ₃ のような誘
電体層，第２層にｄ＝１００ｎｍのＡｌのような金属膜
層，第３層にｄ＝１００ｎｍのＣｅＦ₃ のような誘電体
層というような膜構成をとる事によって実用レベルの膜
強度を得る方法が開示されている。Therefore, the following inventions have been proposed as a method for solving the above-mentioned drawbacks. For example, Japanese Patent Laid-Open No. 2-6
In the invention described in Japanese Patent No. 6157, the first side from the substrate side
A dielectric layer such as CeF ₃ with a physical film thickness d = 100 nm, a metal film layer such as Al with d = 100 nm for the second layer, and a dielectric film such as CeF ₃ with d = 100 nm for the third layer. A method for obtaining a practical level of film strength by taking a film structure such as a body layer is disclosed.

【０００６】[0006]

【発明が解決しようとする課題】しかるに、前記特開平
２−６６１５７号公報記載の発明にように、基板と金属
反射膜との間に誘電体層を挟んで密着強度を上げようと
する場合、誘電体層を成膜することは材料費の増大およ
びタクトタイムの増加を招き、結果としてコストが増大
してしまう。従って、合成樹脂製基板を用いた場合の大
きな特徴であるコスト面でのメリットを充分に活かせな
いという結果になる。また、特に裏面反射鏡として用い
る場合は反射率の低下をも引き起こす。However, as in the invention described in JP-A-2-66157, when a dielectric layer is sandwiched between the substrate and the metal reflection film to increase the adhesion strength, Forming the dielectric layer causes an increase in material cost and an increase in tact time, resulting in an increase in cost. Therefore, the result is that the advantage in terms of cost, which is a major feature of using the synthetic resin substrate, cannot be fully utilized. Further, when it is used as a back surface reflecting mirror, it causes a decrease in reflectance.

【０００７】因って、本発明は前記従来技術における欠
点に鑑みて開発されたもので、誘電体層のアンダーコー
トなしに基本的な光学特性（分光反射率特性）を再現性
を含めて充分に満足するのみならず、密着性あるいは耐
久性試験後においても優れた性能を有する合成樹脂製反
射鏡の作成方法の提供を目的とする。Therefore, the present invention was developed in view of the above-mentioned drawbacks of the prior art, and the basic optical characteristics (spectral reflectance characteristics) including the reproducibility are sufficient without the undercoat of the dielectric layer. It is an object of the present invention to provide a method for producing a synthetic resin reflecting mirror which satisfies not only the above, but also has excellent performance even after an adhesion test or a durability test.

【０００８】[0008]

【課題を解決するための手段】本発明は、合成樹脂製基
板上に金属膜のコーティングを施す反射鏡の作成方法に
おいて、反射膜成膜の前に基板を紫外線およびオゾンガ
スにさらす方法である。SUMMARY OF THE INVENTION The present invention is a method for producing a reflecting mirror in which a metal film is coated on a synthetic resin substrate, and the substrate is exposed to ultraviolet rays and ozone gas before the formation of the reflecting film.

【０００９】[0009]

【作用】本発明では、合成樹脂製基板に紫外線を照射す
ることにより基板を構成する有機物のボンドが切られ
る。同時に、オゾンガスにさらされることにより低級分
子の酸化が起こり、基板表面に存在していた有機系不純
物が取り除かれる。また、紫外線によってボンドが切ら
れることにより、基板表面に活性基が形成され、金属と
の結合を起こし易くなる。このふたつの効果によって金
属反射膜と、合成樹脂製基板との密着強度を実用レベル
にまで向上させることができる。According to the present invention, the organic substance constituting the substrate is cut off by irradiating the synthetic resin substrate with ultraviolet rays. At the same time, exposure to ozone gas causes oxidation of lower molecules, and organic impurities existing on the substrate surface are removed. Further, when the bond is broken by the ultraviolet rays, an active group is formed on the surface of the substrate, which facilitates bonding with a metal. Due to these two effects, the adhesion strength between the metal reflection film and the synthetic resin substrate can be improved to a practical level.

【００１０】[0010]

【実施例１】本実施例では、入射角度４５°の光に対す
る裏面反射鏡を形成した。Example 1 In this example, a back reflector for light with an incident angle of 45 ° was formed.

【００１１】屈折率ｎ＝１．５８のポリカーボネート樹
脂（ＰＣ）からなる合成樹脂製基板の表面を波長１８５
ｎｍの紫外線光源から２０ｍｍの位置に配し、空気中で
それぞれ３０秒，６０秒，９０秒，１２０秒間紫外線を
照射することによって、紫外線およびその紫外線で空気
中の酸素から発生させたオゾンにさらす前処理を施した
のちに真空槽内にいれ、真空度５×１０^-6Ｔｏｒｒに達
した後に、Ａｒガスを３×１０^-3Ｔｏｒｒ導入し、投入
電力２００ＷのＤＣマグネトロンスパッタリング法によ
ってＡｌを６０ｎｍ成膜した。すなわち、図１に示すよ
うに、基板１上へ上記前処理を施したのちに第１層の膜
２を６０ｎｍ成膜した。A surface of a synthetic resin substrate made of a polycarbonate resin (PC) having a refractive index n = 1.58 has a wavelength of 185.
It is placed at a position of 20 mm from a UV light source of nm and exposed to UV rays and ozone generated from oxygen in the air by irradiating UV rays in the air for 30 seconds, 60 seconds, 90 seconds and 120 seconds, respectively. After pretreatment, put in a vacuum chamber, and after reaching a vacuum degree of 5 × 10 ⁻⁶ Torr, introduce Ar gas at 3 × 10 ⁻³ Torr, and apply Al to 60 nm by DC magnetron sputtering with an input power of 200 W. A film was formed. That is, as shown in FIG. 1, after performing the above-described pretreatment on the substrate 1, the first layer film 2 was formed to a thickness of 60 nm.

【００１２】[0012]

【表１】 [Table 1]

【００１３】以上の様にして得られた本実施例の裏面反
射鏡について、入射角４５°に対する分光反射率を測定
したところ、図２のようになった。図２は縦軸に分光反
射率を、横軸に波長をそれぞれとったもので、図２から
わかるように本実施例の裏面反射鏡は初期性能としての
基本的な光学特性（可視光域４００〜７００ｎｍで８０
％以上の分光反射率）を有していた。With respect to the rear surface reflecting mirror of this embodiment obtained as described above, the spectral reflectance at an incident angle of 45 ° was measured, and the result was as shown in FIG. FIG. 2 shows the spectral reflectance on the vertical axis and the wavelength on the horizontal axis. As can be seen from FIG. 2, the rear surface reflecting mirror of this embodiment has basic optical characteristics (visible light range 400) as initial performance. 80 at ~ 700 nm
% Or more).

【００１４】また、本実施例の裏面反射鏡の膜表面にセ
ロハンテープ（幅１８ｍｍ）を接着させた後、接着面と
約４５°の角度でセロハンテープを取り除く密着性試験
をサンプル２０個につき行った。Further, after adhering cellophane tape (width 18 mm) to the film surface of the back reflecting mirror of this embodiment, an adhesion test for removing the cellophane tape at an angle of about 45 ° with the adhering surface was carried out on 20 samples. It was

【００１５】さらに、本実施例の裏面反射鏡について、
対環境試験として、−２０℃→常温（２０〜２５℃）→
＋６０℃を各温度で２時間保持し、５回繰り返す熱衝撃
試験を行った。Further, regarding the rear surface reflecting mirror of this embodiment,
As an environmental test, -20 ° C → normal temperature (20 to 25 ° C) →
The temperature of + 60 ° C. was maintained for 2 hours at each temperature, and a thermal shock test was repeated 5 times.

【００１６】表３には本実施例（実施例１）およびその
比較例として本実施例と同様の成膜法であるが紫外線オ
ゾン処理をしていない基板について、初期の密着性試験
および対環境試験後の密着性試験の結果を示す。Table 3 shows the initial adhesion test and the environment resistance of the substrate of this example (Example 1) and its comparative example, which had the same film-forming method as this example but was not subjected to ultraviolet ozone treatment. The result of the adhesion test after the test is shown.

【００１７】[0017]

【表３】 [Table 3]

【００１８】表３からもわかるように、紫外線オゾン処
理を行ったものでは、成膜初期および対環境試験後の膜
剥離や異常はみられなかった。As can be seen from Table 3, no peeling or abnormality was observed in the film subjected to the ultraviolet ozone treatment at the initial stage of film formation and after the environmental test.

【００１９】[0019]

【実施例２】本実施例では、入射角４５°の光に対する
表面反射鏡を形成した。[Embodiment 2] In this embodiment, a surface reflecting mirror for light having an incident angle of 45 ° is formed.

【００２０】屈折率ｎ＝１．５３のアモルファスポリオ
レフィン樹脂（ＡＰＯ）からなる合成樹脂製基板の表面
を波長１８５ｎｍの紫外線光源から２０ｍｍの位置に配
し、空気中でそれぞれ３０秒，６０秒，９０秒，１２０
秒間紫外線を照射することによって、紫外線およびその
紫外線で空気中の酸素から発生させたオゾンにさらす前
処理を施したのちに真空槽内にいれ、真空度５×１０^-6
Ｔｏｒｒに達した後に、抵抗加熱を用いた真空蒸着法に
よってＡｌを６０ｎｍ成膜し、引き続き電子ビーム蒸着
法によりＳｉＯ₂ を２００ｎｍ成膜した。すなわち、図
３に示すように、基板３上へ上記前処理を施したのちに
第１層の膜４を６０ｎｍ成膜し、さらに膜４の上に第２
層の膜５を２００ｎｍ成膜した。The surface of a synthetic resin substrate made of an amorphous polyolefin resin (APO) having a refractive index n = 1.53 is placed at a position 20 mm away from an ultraviolet light source having a wavelength of 185 nm, and is placed in air for 30 seconds, 60 seconds, and 90 seconds, respectively. Second, 120
By irradiating with ultraviolet rays for 2 seconds, it is exposed to ultraviolet rays and ozone generated from oxygen in the air by the ultraviolet rays. After pretreatment, it is placed in a vacuum chamber and the degree of vacuum is 5 × 10 ^-6
After reaching Torr, Al was deposited to a thickness of 60 nm by a vacuum vapor deposition method using resistance heating, and subsequently, SiO ₂ was deposited to a thickness of 200 nm by an electron beam vapor deposition method. That is, as shown in FIG. 3, after performing the above-mentioned pretreatment on the substrate 3, a first layer film 4 is formed to a thickness of 60 nm, and a second layer 4 is formed on the film 4.
Layer film 5 was deposited to 200 nm.

【００２１】[0021]

【表２】 [Table 2]

【００２２】以上の様にして得られた本実施例の表面反
射鏡について、入射角４５°に対する分光反射率を測定
したところ、図４のようになった。図４は縦軸に分光反
射率を、横軸に波長をそれぞれとったもので、図４から
わかるように本実施例の表面反射鏡は、初期性能として
の基本的な光学特性（可視光域４００〜７００ｎｍで８
０％以上の分光反射率）を有していた。With respect to the surface reflecting mirror of this embodiment obtained as described above, the spectral reflectance at an incident angle of 45 ° was measured, and the result was as shown in FIG. FIG. 4 shows the spectral reflectance on the vertical axis and the wavelength on the horizontal axis. As can be seen from FIG. 4, the surface reflecting mirror of this embodiment has basic optical characteristics (visible light range) as initial performance. 8 at 400-700 nm
It had a spectral reflectance of 0% or more).

【００２３】また、本実施例の表面反射鏡の膜表面にセ
ロハンテープ（幅１８ｍｍ）を接着させた後、接着面と
約４５°の角度でセロハンテープを取り除く密着性試験
をサンプル２０個につき行った。Further, after adhering cellophane tape (width 18 mm) to the film surface of the surface reflecting mirror of the present embodiment, an adhesion test for removing the cellophane tape at an angle of about 45 ° with respect to the adhering surface was carried out on 20 samples. It was

【００２４】さらに、本実施例の表面反射鏡について、
対環境試験として、−２０℃→常温（２０〜２５℃）→
＋６０℃を角温度で２時間保持し、５回繰り返す熱衝撃
試験を行った。Furthermore, regarding the surface reflecting mirror of this embodiment,
As an environmental test, -20 ° C → normal temperature (20 to 25 ° C) →
A thermal shock test was carried out by keeping + 60 ° C. at an angular temperature for 2 hours and repeating 5 times.

【００２５】表３には本実施例（実施例２）およびその
比較例として本実施例と同様の成膜法であるが紫外線オ
ゾン処理をしていない基板について、初期の密着性試験
および対環境試験後の密着性試験の結果を示す。Table 3 shows this example (Example 2) and its comparative example, which had the same film forming method as this example but was not subjected to ultraviolet ozone treatment. The result of the adhesion test after the test is shown.

【００２６】[0026]

【表３】[Table 3]

【００２７】表３からもわかるように，紫外線オゾン処
理を行ったものでは、成膜初期および対環境試験後の膜
剥離や異常は見られなかった。As can be seen from Table 3, no peeling or abnormality was observed in the film subjected to the ultraviolet ozone treatment at the initial stage of film formation and after the environmental test.

【００２８】[0028]

【発明の効果】以上説明したように、本発明に係る合成
樹脂製反射鏡の作成方法によれば、誘電体層のアンダー
コートなしに基本的な光学特性（分光反射率特性）を満
足できるとともに、反射膜にマイクロクラックの発生が
ない。また、合成樹脂製基板の変形や劣化がなく、外観
特性が良好である。さらに、耐久性能試験後において
も、膜剥離やマイクロクラックの発生がなく、合成樹脂
製基板の変形や劣化もない。As described above, according to the method for producing a synthetic resin reflecting mirror of the present invention, basic optical characteristics (spectral reflectance characteristics) can be satisfied without undercoating the dielectric layer. No microcracks are generated in the reflective film. In addition, the synthetic resin substrate is not deformed or deteriorated, and the appearance characteristics are good. Further, even after the durability performance test, film peeling and microcracks are not generated, and the synthetic resin substrate is neither deformed nor deteriorated.

【図面の簡単な説明】[Brief description of drawings]

【図１】実施例１を示す部分断面図である。FIG. 1 is a partial cross-sectional view showing a first embodiment.

【図２】実施例１の光学特性を示すグラフである。FIG. 2 is a graph showing optical characteristics of Example 1.

【図３】実施例２を示す部分断面図である。FIG. 3 is a partial cross-sectional view showing a second embodiment.

【図４】実施例２の光学特性を示すグラフである。FIG. 4 is a graph showing optical characteristics of Example 2.

【符号の説明】[Explanation of symbols]

１，３ 基板 ２，４ 第１層の膜 ５ 第２層の膜 1,3 Substrate 2,4 First layer film 5 Second layer film

Claims (1)

【特許請求の範囲】 【請求項１】 合成樹脂製基板上に金属膜のコーティン
グを施す反射鏡の作成方法において、反射膜成膜の前に
基板を紫外線およびオゾンガスにさらすことを特徴とす
る合成樹脂製反射鏡の作成方法。Claim: What is claimed is: 1. A method for producing a reflecting mirror in which a synthetic resin substrate is coated with a metal film, wherein the substrate is exposed to ultraviolet rays and ozone gas before the formation of the reflecting film. How to make a resin mirror.