201105495 六、發明說明： 【發明所屬之技術領域】 本發明關於照明的反射板、液晶的螢光燈背面板等中 所用的高反射預塗之鋁合金板。 再者，於本發明中，鋁合金板係包含純鋁板及鋁合金 板。 【先前技術】 以往，作爲家電製品或OA機器的殼體等之材料，廣 泛使用預塗之鋁合金板。 預塗之鋁合金板係將鋁合金板的表面塗覆在合成樹脂 塗膜上所成，具有輕量且成形後不需要施予塗裝的優異特 性。 最近，於家電製品或OA機器中，除了輕量化、小型 化、高性能化，亦愈來愈往低價格化進展，隨著此，殼體 等中所用的材料之高性能化、低成本化係成爲重要課題。 又，最近，家電製品或OA機器係希望薄型類型，特 殊的形狀亦增加，對於殻體等中所用的材料，強烈要求可 成形爲各式各樣形狀的優異.成形性。 再者，於液晶顯示器的背側面所配置的液晶背面板， 會要求在可見光的全波長進行均勻的反射，而且對於來自 螢光燈的發熱，必須有耐熱性及高壽命。 而且，作爲上述液晶背面板，迄今爲此，使用高反射 的薄膜或在鋁合金板上黏貼有高反射的薄膜者等（專利文 201105495 獻1〜6 )。 [先前技術文獻] [專利文獻] [專利文獻1]特開平8- 1 60208號公報 [專利文獻2]特開平9-251805號公報 [專利文獻3]特開2002-254558號公報 [專利文獻4]特開平1 1 -29745號公報 [專利文獻5]特開2002-258020號公報 [專利文獻6] WO97/01 1 17號公報 【發明內容】 發明所欲解決的問題 然而，例如爲了製作黏貼有高反射的薄膜之鋁合金板 等，需要複雜的製程，製造成本高。此在液晶背面板之今 後的低價格化係成爲大問題。因此，希望開發出製造成本 低、具有高反射特性的材料。 又，作爲具有上述高反射特性的材料，亦要求具備即 使複雜的加壓成形也耐得住的成形性，而且薄壁g @胃 性。 本發明係鑒於如此以往的問題點而完成者，$ _丨共司· 薄壁輕量化、製造成本減低、成形性及反射特,丨生丨憂g @胃 反射預塗之鋁合金板。 解決問題的手段 -6 - 201105495 本發明爲一種高反射預塗之鋁合金板，其係具有由鋁 合金板所成的基板、與形成在該基板的一面或兩面上之預 塗層的預塗之鋁合金板，其特徵爲： 上述基板之至少一面上所形成的預塗層，係具有相對 於100重量份的基礎樹脂而言，含有30重量份以上的高反 射物質之高反射層， 上述基礎樹脂係在正反射率80%以上的鋁合金板上形 成厚度ΙΟμπι的塗膜之際的塗裝前後之正反射降低率爲10% 以下， 上述高反射物質係由硫酸鋇、氧化鈦、碳酸鈣、硫酸 鈣、氧化鋁、氧化鎂、硫酸鎂、矽酸鎂、氧化鋅、玻璃、 氮化鋁、氮化硼、矽石、氧化锆 '中空玻璃珠中的1種或2 種以上所構成， 上述高反射物質的平均粒徑係0.1〜ΙΟμιη， 上述高反射層的膜厚係20〜150μπι (申請專利範圍第i 項）。 發明的效果 本發明的高反射預塗之鋁合金板係使用鋁合金板當作 基板，而且在其一面或兩面上具有預塗層，該預塗層具有 具上述特定構成的高反射層。藉此，上述高反射預塗之鋁 合金板係可薄壁輕量化、製造成本減低，成爲成形性及反 射特性優異者。 上述高反射層係在具有透光性的基礎樹脂中含有特定 201105495 量的折射率大之上述特定高反射物質。即，侵入上述高反 射層的光，由於穿透上述基礎樹脂，在上述基礎樹脂與上 述高反射物質的界面進行反射，故高反射層可得到高的反 射率。因此，可對預塗之鋁板給予優異的反射特性。 又，上述高反射層，由於爲20〜150 μηι的膜厚且具有 充分的反射特性，故可能薄壁輕量化。 還有，構成上述高反射層的基礎樹脂以及高反射物質 係比較廉價。又，上述預塗層係可比較容易地形成。因此 ，可減低製造成本。 又，由於以上述預塗層來塗覆鋁合金板的表面，故具 備即使複雜的加壓成形也能耐得住的成形性。 如此，若依照本發明，可提供能薄壁輕量化、製造成 本減低、成形性及反射特性優異的高反射預塗之鋁合金板 【實施方式】 實施發明的形態 本發明的預塗之鋁合金板係如上述地，具有由鋁合金 板所成的基板、與形成在該基板的一面或兩面上之預塗層 〇 上述預塗層係可僅由上述高反射層所構成，亦可爲除 了高反射層，例如亦可層合用於確保與原材料的密接性之 底塗層、用於賦予加工性的潤滑層而構成。 又’上述高反射層本身係可僅由一層的高反射層所形 -8- 201105495 成，也可層合複數層的高反射層而形成。 於上述預塗層僅形成在上述基板的一面之情況中，該 預塗層必須具有高反射層，於上述預塗層設置在上述基板 的兩面之情況中，可爲一面上所形成的預塗層具有高反射 層，而另一面是僅由上述高反射層以外的層所成的預塗層 ，也可兩方的預塗層具有高反射層。 還有，上述高反射層中所含有的上述高反射物質之含 量（含有複數種類的高反射物質時，爲其合計含量），係 相對於100重量份的基礎樹脂而言爲30重量份以上。 於上述高反射物質的含量相對於100重量份的基礎樹 脂而言未達30重量份時，反射率有降低之虞。 又，於含有複數的成分的上述高反射物質時，各自單 獨的含量相對於1〇〇重量份的上述基礎樹脂而言較佳爲30 重量份以上。 還有，上述高反射物質的含量（含有複數種類的高反 射物質時，爲其合計含量），係相對於1 〇〇重量份的上述 基礎樹脂而言較佳爲3 00重量份以下（申請專利範圍第2項 )0 於上述高反射物質的含量相對於1〇〇重量份的基礎樹 脂而言超過300重量份時，高反射物質由塗膜的脫落數有 增加之虞。又，加工時在預塗層有容易發生裂紋之虞。再 者，於塗膜的加工性等的性能變差時，亦可爲超過300重 量份的含量。 又，上述高反射物質的含量係相對於100重量份的基 -9- 201105495 礎樹脂而言更佳爲100〜200重量份。 還有，上述基礎樹脂係具有在正反射率80%以上的鋁 合金板上形成厚度10 μπι的塗膜之際的塗裝前後之正反射降 低率爲10%以下的特性。 於正反射率80%以上的鋁合金板上形成由上述基礎樹 脂所成之厚度ΙΟμηι的塗膜之際的塗裝前後之正反射降低率 超過10%時，光的損失變大，反射率有降低之虞。 再者，上述正反射降低率係可由100— {(塗裝後正反 射率/塗裝前正反射率）xl〇〇}(%)來導出。 作爲上述基礎樹脂，例如可舉出不飽和聚酯樹脂、脂 肪酸改性的聚酯樹脂（醇酸樹脂）、無油的醇酸樹脂、綿 狀聚酯樹脂等的聚酯系樹脂、丙烯酸樹脂、環氧樹脂、聚 胺基甲酸酯樹脂、酚系樹脂等的塗料。 又，上述高反射物質係由硫酸鋇、氧化鈦、碳酸鈣、 硫酸鈣、氧化鋁、氧化鎂、硫酸鎂、矽酸鎂、氧化鋅、玻 璃、氮化鋁、氮化硼、矽石、氧化銷、中空玻璃珠中的1 種或2種以上所構成。 還有，作爲上述中空玻璃珠的玻璃成分，可採用矽酸 玻璃、硼酸鈉玻璃、矽石玻璃、其它各樣種類的玻璃。 再者，上述高反射物質的平均粒徑爲〇」〜ΙΟμηα。 當上述高反射物質的平均粒徑未達〇.1 μπι時，可見光 容易透過，反射率有降低之虞。另一方面，當上述高反射 物質的平均粒徑超過ΙΟμιη時，有上述高反射物質由塗膜的 脫落數增加之問題。又’加工時在預塗層有容易發生裂紋 -10- 201105495 之虞。 而且，上述高反射物質的平均粒徑更佳爲0.2〜1.0 μιη 〇 上述高反射物質的平均粒徑係一次粒子的中値粒徑（ D50 )，以電子顯微鏡來觀察，藉由圖像解析程式來測定 各自的粒徑而算出。 又，上述高反射層的膜厚爲20〜150 μιη。 爲了得到更高的高反射率，高反射層的膜厚較佳爲 ΙΟΟμπι以上，於加工嚴苛時，較佳爲未達ΙΟΟμιη。 於上述高反射層的膜厚未達20μιη時，反射率顯著降低 。另一方面，於上述高反射層的膜厚超過15 0μιη時，雖然 有利於反射率的提高，但是有成本升高的問題。又，加工 時在預塗層有容易發生裂紋之虞》 於具有上述高反射層的預塗層僅由高反射層所構成時 ，上述預塗層爲20〜150μιηβ 又，於具有上述高反射層的預塗層，但是層合高反射 層與不具有高反射特性的層而構成時，上述預塗層的膜厚 較佳爲40〜120μηι。 還有，於上述預塗之鋁合金板中，具有上述高反射層 的預塗層之最外層，較佳係相對於100重量份的上述基礎 塗膜而言，含有0.05〜3重量份的由動物性蠟、植物性蠟 、合成蠟、石油蠟中的1種或2種以上所構成的內蠟（i η n e r w a x )(申請專利範圍第3項）。 於此情況下，可對預塗之鋁合金板給予滑動性提高效 -11 - 201105495 果。 作爲上述動物性蠟，例如可舉出羊毛脂等。 又，作爲上述植物性蠟，例如可舉出巴西棕櫚蠟等。 還有’作爲上述合成蠟，例如可舉出聚乙烯蠟或費-托（Fischer-Tropsch)蠟等。 再者，作爲上述石油蠘，例如可舉出石蠟、微晶蠟或 石蠟脂等。 於上述內蠟的含量未達0.05%時，無法得到滑動性提 高的效果。另一方面，於上述內蠟的含量超過3重量份時 ，有成本升高的問題。 又，於上述預塗層與上述基板之間，較佳爲形成有化 成處理皮膜（申請專利範圍第4項）。 於此情況下，可有效地提高上述基板與上述預塗層的 密接性。又，可實現優異的耐蝕性，可抑制在水、氯化合 物等的腐蝕性物質滲透至鋁合金板的表面之際所引起的塗 膜下腐蝕，可謀求塗膜裂紋或塗膜剝離的防止。 作爲上述化成處理皮膜，可採用藉由磷酸鉻酸鹽、鉻 酸鉻酸鹽等的鉻酸鹽處理、鉻化合物以外的磷酸鈦或磷酸 錐、磷酸鉬、磷酸鋅等之非鉻酸鹽處理等的化學皮膜處理 的所謂化成處理而得之皮膜。 再者，於上述鉻酸鹽處理或非鉻酸鹽處理等的化成處 理方法中，有反應型及塗佈型，但於本發明中，可以採用 任何的手法。 -12- 201105495 〔實施例〕 (實施例1 ) 於本例中，使用圖1及圖2來說明本發明的實施例中之 高反射預塗之鋁合金板。本發明係不受此等實施例所限定 〇 於本例中，作爲本發明的實施例，製作1 2種類的預塗 之鋁合金板（試料E1〜試料E12)，及作爲本發明的比較 例，製作8種類的預塗之鋁合金板（試料C1〜試料C8)。 如圖1所示地，本例的高反射預塗之鋁合金板1 (試料 E1〜試料E12)係具有由鋁合金板所成的基板2、與形成在 該基板2的一面上之預塗層3的預塗之鋁合金板1。 於製作本例的高反射預塗之鋁合金板1時，首先準備 厚度0.5〇1111的1050-1124銘合金板當作由銘合金板所成的基 板2。 又，作爲構成上述預塗層3的基礎樹脂42，準備在正 反射率8 0 %以上的鋁合金板上形成厚度1 0 μιη的塗膜之際的 塗裝前後之正反射降低率爲5 %的聚酯樹脂、上述正反射降 低率爲20%的上述正反射降低率爲6%之胺基甲酸酯、上述 正反射降低率爲10 %之丙烯酸樹脂。 上述正反射降低率係藉由在正反射率84%爲鋁合金板 之表面上以單體塗佈ΙΟμηι的上述基礎樹脂，進行測定塗裝 後的正反射率之試驗，以正反射降低率=1 〇〇- {(塗裝後的 正反射率（％ ) / 8 4 % ) X 1 0 〇 } ( % )來算出。 又，作爲構成上述預塗層3的高反射物質41，準備平 -13- 201105495 均粒徑爲〇.5μιη、Ο.ίμιη、〇_〇4〇1的3種類之氧化鈦、平均 粒徑爲Ιμηι、ΙΟμηι、15μηι的3種類之硫酸鋇。 然後’以鹼系脫脂劑將上述基板2脫脂後，在磷酸鉻 酸鹽浴中實施磷酸鉻酸鹽處理而形成化成處理皮膜之鉻酸 鹽皮膜5。鉻酸鹽皮膜量係使皮膜中的Cr含量成爲 20士5mg/m2之量。 其次，關於各試料E1〜試料E12、試料C1〜試料C8， 使用桿塗機，將於表1所示的基礎樹脂42中含有表1所示含 量的表1所示高反射物質41之塗料，塗佈在上述基板2的化 成處理皮膜5上。然後，在24〇°C的烘箱中烘烤6〇秒，以使 鋁表面的溫度成爲230°C，進行硬化而形成預塗層3 (高反 射層4 )，得到預塗之鋁合金板1 (試料E 1〜試料E〗2及試 料C1〜試料C8 )。 上述預塗層3係具有如表1所示的膜厚’以一層或複數 層來形成。 -14- 201105495 (I撇)201105495 VI. Description of the Invention: [Technical Field] The present invention relates to a highly reflective precoated aluminum alloy plate used in an illumination reflector, a liquid crystal fluorescent lamp back panel, and the like. Further, in the present invention, the aluminum alloy sheet comprises a pure aluminum plate and an aluminum alloy plate. [Prior Art] Conventionally, a precoated aluminum alloy sheet has been widely used as a material for a home appliance or a casing of an OA machine. The precoated aluminum alloy sheet is formed by coating the surface of the aluminum alloy sheet on a synthetic resin coating film, and has excellent properties such that it is lightweight and does not need to be applied after molding. In recent years, in addition to weight reduction, miniaturization, and high performance, home appliances and OA machines are becoming more and more expensive, and the materials used in the casings and the like are improved in performance and cost. The system has become an important issue. Further, recently, home electric appliances and OA machines are expected to have a thin type, and a special shape is also increased. For materials used in a casing or the like, it is strongly required to be formed into various shapes and excellent formability. Further, the liquid crystal back panel disposed on the back side of the liquid crystal display is required to be uniformly reflected at the entire wavelength of visible light, and heat resistance and high life are required for heat generation from the fluorescent lamp. Further, as the above-mentioned liquid crystal back panel, a highly reflective film or a highly reflective film is adhered to the aluminum alloy plate (Patent Document 201105495, 1 to 6). [PATENT DOCUMENT] [Patent Document 1] JP-A-2002-254558 (Patent Document 3) JP-A-2002-254558 (Patent Document 4) [Patent Document 5] JP-A-2002-258020 (Patent Document 6) WO97/01 1 17 SUMMARY OF THE INVENTION Problems to be Solved by the Invention However, for example, in order to make a paste A highly reflective film of an aluminum alloy plate or the like requires a complicated process and is expensive to manufacture. This low cost of the liquid crystal back panel has become a big problem. Therefore, it has been desired to develop a material having low manufacturing cost and high reflection characteristics. Further, as a material having the above-mentioned high reflection property, it is also required to have moldability which is resistant even with complicated press molding, and a thin wall g @胃性. The present invention has been completed in view of such problems in the past, and has been reduced in thickness, reduced in manufacturing cost, formability, and reflective, and has been used to reflect pre-coated aluminum alloy sheets. Means for Solving the Problem-6 - 201105495 The present invention is a highly reflective precoated aluminum alloy plate having a substrate formed of an aluminum alloy plate and a precoat coated with a precoat formed on one or both sides of the substrate The aluminum alloy sheet characterized in that the precoat layer formed on at least one surface of the substrate has a highly reflective layer containing 30 parts by weight or more of a highly reflective substance with respect to 100 parts by weight of the base resin. The base resin is a positive reflection reduction rate of 10% or less before and after coating when a coating film having a thickness of ΙΟμπι is formed on an aluminum alloy plate having a regular reflectance of 80% or more, and the highly reflective substance is made of barium sulfate, titanium oxide, or carbonic acid. One or more of calcium, calcium sulfate, aluminum oxide, magnesium oxide, magnesium sulfate, magnesium niobate, zinc oxide, glass, aluminum nitride, boron nitride, vermiculite, and zirconia hollow glass beads The high-reflection material has an average particle diameter of 0.1 to ΙΟμιη, and the high-reflection layer has a film thickness of 20 to 150 μm (application patent range i). EFFECTS OF THE INVENTION The highly reflective precoated aluminum alloy sheet of the present invention uses an aluminum alloy sheet as a substrate and has a precoat layer on one or both sides thereof, the precoat layer having a highly reflective layer having the above specific configuration. As a result, the highly reflective precoated aluminum alloy sheet can be made thinner and lighter, and the manufacturing cost is reduced, and it is excellent in formability and reflection characteristics. The highly reflective layer contains the specific highly reflective material having a specific refractive index of a specific amount of 201105495 in a base resin having light transmissivity. In other words, the light that has entered the high-reflection layer is reflected by the interface between the base resin and the highly reflective material by penetrating the base resin, so that the high-reflection layer can obtain a high reflectance. Therefore, excellent reflection characteristics can be imparted to the precoated aluminum sheet. Further, since the highly reflective layer has a film thickness of 20 to 150 μm and has sufficient reflection characteristics, it is possible to reduce the thickness of the thin wall. Further, the base resin and the highly reflective material constituting the above-mentioned highly reflective layer are relatively inexpensive. Further, the above precoat layer can be formed relatively easily. Therefore, the manufacturing cost can be reduced. Further, since the surface of the aluminum alloy plate is coated with the above precoat layer, it has moldability which can withstand even complicated press molding. According to the present invention, it is possible to provide a highly reflective precoated aluminum alloy sheet which is thinner and lighter in weight, lower in manufacturing cost, and excellent in formability and reflection characteristics. [Embodiment] The precoated aluminum alloy of the present invention. As described above, the plate has a substrate made of an aluminum alloy plate and a precoat layer formed on one or both sides of the substrate. The precoat layer may be composed of only the high reflection layer, or may be The highly reflective layer may be formed, for example, by laminating an undercoat layer for ensuring adhesion to a material and a lubricating layer for imparting workability. Further, the above-mentioned highly reflective layer itself may be formed of only one layer of a highly reflective layer, -8 to 201105495, or may be formed by laminating a plurality of layers of a highly reflective layer. In the case where the precoat layer is formed only on one side of the substrate, the precoat layer must have a highly reflective layer. In the case where the precoat layer is disposed on both sides of the substrate, the precoat layer may be formed on one side. The layer has a highly reflective layer and the other side is a precoat layer formed only of layers other than the above-mentioned highly reflective layer, or both of the precoat layers may have a highly reflective layer. In addition, the content of the highly reflective material contained in the high-reflection layer (the total content of the high-reflection substance in a plurality of types) is 30 parts by weight or more based on 100 parts by weight of the base resin. When the content of the above highly reflective material is less than 30 parts by weight based on 100 parts by weight of the base resin, the reflectance is lowered. Further, in the case of the above-mentioned highly reflective material containing a plurality of components, the content of each of the above-mentioned high-reflection materials is preferably 30 parts by weight or more based on 1 part by weight of the base resin. In addition, the content of the high-reflection substance (the total content of the high-reflection substance in a plurality of types) is preferably 300 parts by weight or less based on 1 part by weight of the base resin (patent pending) When the content of the above-mentioned highly reflective material exceeds 300 parts by weight based on 1 part by weight of the base resin, the number of peeling off of the highly reflective material by the coating film is increased. Moreover, there is a tendency for cracks to occur in the precoat layer during processing. In addition, when the performance such as the processability of the coating film is deteriorated, the content may be more than 300 parts by weight. Further, the content of the above-mentioned highly reflective substance is more preferably from 100 to 200 parts by weight based on 100 parts by weight of the base -9 to 201105495 base resin. In addition, the base resin has a characteristic that the positive reflection reduction rate before and after coating is 10% or less when a coating film having a thickness of 10 μm is formed on an aluminum alloy plate having a regular reflectance of 80% or more. When the coating film having a thickness of ΙΟμηι formed of the base resin is formed on an aluminum alloy plate having a positive reflectance of 80% or more, the positive reflection reduction rate before and after coating is more than 10%, the light loss is increased, and the reflectance is increased. Reduce the embarrassment. Further, the above-described regular reflection reduction rate can be derived from 100 - {(positive reflectance after painting / positive reflectance before painting) xl 〇〇} (%). Examples of the base resin include a polyester resin such as an unsaturated polyester resin, a fatty acid-modified polyester resin (alkyd resin), an oil-free alkyd resin, and a cotton-like polyester resin, and an acrylic resin. A coating material such as an epoxy resin, a polyurethane resin, or a phenol resin. Further, the highly reflective substance is made of barium sulfate, titanium oxide, calcium carbonate, calcium sulfate, aluminum oxide, magnesium oxide, magnesium sulfate, magnesium niobate, zinc oxide, glass, aluminum nitride, boron nitride, vermiculite, oxidation. One or two or more types of pins and hollow glass beads are used. Further, as the glass component of the hollow glass beads, phthalic acid glass, sodium borate glass, vermiculite glass, and other various types of glass can be used. Further, the average particle diameter of the highly reflective material is 〇"~ΙΟμηα. When the average particle diameter of the above highly reflective material is less than 0.1 μm, visible light is easily transmitted, and the reflectance is lowered. On the other hand, when the average particle diameter of the highly reflective material exceeds ΙΟμηη, there is a problem that the number of peeling off of the highly reflective material is increased by the coating film. Also, during the processing, the precoat layer is prone to cracks -10- 201105495. Further, the average particle diameter of the highly reflective material is more preferably 0.2 to 1.0 μm. The average particle diameter of the highly reflective material is the median diameter (D50) of the primary particles, which is observed by an electron microscope, and is analyzed by an image analysis program. The particle diameters were measured and calculated. Further, the film thickness of the high reflection layer is 20 to 150 μm. In order to obtain a higher high reflectance, the film thickness of the highly reflective layer is preferably ΙΟΟμπι or more, and when the processing is severe, it is preferably less than ΙΟΟμιη. When the film thickness of the above-mentioned highly reflective layer is less than 20 μm, the reflectance is remarkably lowered. On the other hand, when the film thickness of the high-reflection layer exceeds 150 μm, the reflectance is improved, but there is a problem that the cost is increased. Further, in the case where the precoat layer is susceptible to cracking during processing, when the precoat layer having the high reflection layer is composed only of the high reflection layer, the precoat layer is 20 to 150 μm β and has the above-mentioned high reflection layer. The precoat layer is formed by laminating a highly reflective layer and a layer having no high reflection property, and the film thickness of the precoat layer is preferably 40 to 120 μm. Further, in the precoated aluminum alloy sheet, the outermost layer of the precoat layer having the high reflection layer is preferably contained in an amount of 0.05 to 3 parts by weight based on 100 parts by weight of the base coating film. An internal wax (i η nerwax ) composed of one or more of animal wax, vegetable wax, synthetic wax, and petroleum wax (application patent item 3). In this case, the slidability can be improved on the precoated aluminum alloy sheet -11 - 201105495. Examples of the animal wax include lanolin and the like. Moreover, as the vegetable wax, for example, carnauba wax or the like can be mentioned. Further, as the synthetic wax, for example, a polyethylene wax or a Fischer-Tropsch wax may be mentioned. Further, examples of the petroleum crucible include paraffin wax, microcrystalline wax, and paraffin wax. When the content of the above internal wax is less than 0.05%, the effect of improving the slidability cannot be obtained. On the other hand, when the content of the above internal wax exceeds 3 parts by weight, there is a problem that the cost increases. Further, between the precoat layer and the substrate, a chemical conversion treatment film is preferably formed (article 4 of the patent application). In this case, the adhesion between the substrate and the precoat layer can be effectively improved. Further, it is possible to achieve excellent corrosion resistance, and it is possible to suppress corrosion of the coating film caused by the penetration of corrosive substances such as water and chloride into the surface of the aluminum alloy plate, and to prevent coating film cracking or peeling of the coating film. As the chemical conversion treatment film, chromate treatment such as chromate phosphate or chromate chromate, non-chromate treatment such as titanium phosphate or phosphoric acid cone other than a chromium compound, molybdenum phosphate or zinc phosphate can be used. The chemical film treatment is obtained by a so-called chemical treatment. Further, in the chemical conversion treatment methods such as the chromate treatment or the non-chromate treatment, there are a reaction type and a coating type, but in the present invention, any method can be employed. -12-201105495 [Embodiment] (Embodiment 1) In this example, a highly reflective precoated aluminum alloy sheet according to an embodiment of the present invention will be described with reference to Figs. 1 and 2 . The present invention is not limited to the examples, and is used as an embodiment of the present invention to produce 12 types of precoated aluminum alloy sheets (samples E1 to E12), and as a comparative example of the present invention. Eight types of precoated aluminum alloy sheets (sample C1 to sample C8) were produced. As shown in Fig. 1, the highly reflective precoated aluminum alloy sheet 1 (sample E1 to sample E12) of this example has a substrate 2 made of an aluminum alloy sheet and a precoat layer formed on one side of the substrate 2. Layer 3 precoated aluminum alloy sheet 1. In the case of producing the highly reflective precoated aluminum alloy sheet 1 of this example, first, a 1050-1124 alloy plate having a thickness of 0.5 〇 1111 was prepared as the substrate 2 made of the alloy sheet. In addition, as the base resin 42 constituting the precoat layer 3, a positive reflection reduction rate of 5% before and after coating is prepared when a coating film having a thickness of 10 μm is formed on an aluminum alloy plate having a regular reflectance of 80% or more. The polyester resin has an acrylamide resin having a positive reflection reduction rate of 20% and a urethane resin having a positive reflection reduction rate of 10%. The normal reflection reduction rate is measured by measuring the normal reflectance after coating by applying the above-mentioned base resin to the surface of the aluminum alloy plate at a normal reflectance of 84% on the surface of the aluminum alloy plate, and reducing the regular reflection rate = 1 〇〇- {(positive reflectance after painting (%) / 8 4 % ) X 1 0 〇} ( % ) to calculate. Further, as the highly reflective material 41 constituting the precoat layer 3, three types of titanium oxide having a mean particle diameter of -13.5μιη, Ο.ίμιη, and 〇_〇4〇1 are prepared, and the average particle diameter is Three types of barium sulfate of Ιμηι, ΙΟμηι, and 15μηι. Then, the substrate 2 is degreased with an alkali-based degreaser, and then chromate treatment is carried out in a phosphoric acid chromate bath to form a chromate film 5 of a chemical conversion treatment film. The amount of chromate film is such that the Cr content in the film is 20 ± 5 mg/m 2 . Next, with respect to each of the samples E1 to E12 and the samples C1 to C8, a coating material of the highly reflective material 41 shown in Table 1 in the amount shown in Table 1 was contained in the base resin 42 shown in Table 1 using a bar coater. It is coated on the chemical conversion treatment film 5 of the above-mentioned substrate 2. Then, it was baked in an oven at 24 ° C for 6 seconds to make the temperature of the aluminum surface 230 ° C, and hardened to form a pre-coat layer 3 (high-reflection layer 4), thereby obtaining a pre-coated aluminum alloy plate 1 (sample E 1 to sample E 2 and sample C1 to sample C8). The above precoat layer 3 has a film thickness as shown in Table 1 formed of one layer or plural layers. -14- 201105495 (I撇)
綜合 評價 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 X X X X X X X X 加工性 <1 < 〇 〇 〇 〇 < 〇 ο 0 〇 < X 〇 〇 〇 X X 〇 〇 反射性 評價 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 X X X 〇 〇 X X 全反射率 (%) CO 〇\ 〇\ 00 »η σ\ σ\ ν〇 ON cn 00 荔 Ον Ον ΓΟ σ\ ON 高反射物質 含量 (重量份） t—Η 150 1—Η τ^Η ο ΓΟ 300 τ—Η 300 300 300 yn CA 350 r—Η Τ-Η τ-Η 平均粒徑 (μιη) Ο in ο 〇 〇 ^Ti Ο Ο Ο ο Ο Ο r—< r-H ο Τ—Η Ο Ο 0.06 · ο c5 in 〇 iTi 〇 物質名 氧化鈦 氧化鈦 氧化鈦 氧化鈦 氧化鈦 氧化鈦 氧化鈦 氧化鈦 氧化鈦 硫酸鋇 硫酸鋇 氧化鈦 氧化鈦 氧化鈦 氧化鈦 氧化鈦 氧化鈦 硫酸鋇 氧化鈦 氧化鈦 膜厚 (μιη) ο 100 Ο 120 120 120 120 120 § ο r-H Γ 120 120 ο (Ν r"H 〇 <Ν 正反射降低率 (%) ^Ti IT) in Ό Ό Ο ΙΟ 〇 ο CM 基礎樹脂 聚酯 聚酯 聚酯 聚酯 聚酯 聚酯 聚酯 1 聚酯 聚酯 胺基甲酸酯 胺基甲酸酯 丙烯酸酯 am 細 κ 聚酯 聚酯 聚酯 聚酯 胺基甲酸酯 聚酯 聚酯 試料 No. m CN W 寸 ω in ω Ό ω 00 ω m Ε10 Ell Ε12 Ο CN U cn U δ ΙΟ υ Ό U 卜 U 00 U -15- 201105495 接著，對於所得到的預塗之鋁合金板1，進行反射性 、加工性的評價。 <反射性> . 反射性係藉由測定全反射率來評價。全反射率的測定 係使用村上色彩技術硏究所公司製積分球分光測色計來進 行。以固結有硫酸鋇的微粉末的白色板之全反射率當作 100%，將各個樣品在5 5 0nm的波長的測定値定義爲全反射 率。表1中一倂顯不結果。 於預塗層3的膜厚爲ΙΟΟμηι以上時，將全反射率爲95 % 以上的情況評價爲〇，將全反射率未達9 5 %的情況評價爲X 。又，於預塗層3的膜厚未達ΙΟΟμπι時，將全反射率爲88% 以上的情況評價爲〇，將全反射率未達8 8 %的情況當作不 良，以X記號表示。 再者，圖2中顯示高反射層4的機構。如圖2中所示地 ，高反射層4係使折射率大的上述特定高反射物質41以特 定量含於具有透光性的基礎樹脂42中，而且具有特定的膜 厚。然後，由於侵入上述預塗層3 (高反射層4)的光係穿 透上述基礎樹脂42，在上述基礎樹脂42與述高反射物質41 的界面進行反射，故可得到高的反射率。 <加工性> 加工性係藉由進行90°彎曲及密合彎曲來評價。 將90°彎曲、密合彎曲皆沒有在塗膜上看到裂紋的情 -16- 201105495 況評價爲〇’將僅密合彎曲在塗膜上看到裂紋的情況評價 爲△，將90°彎曲而在塗膜上看到裂紋的情況評價爲X，表i 中一倂顯示結果。將評價爲〇及△的情況當作合格，將評 價爲X的情況當作不合格。 又，表1中所示的綜合評價係將反射性及加工性的評 價皆合格的情況當作合格（評價〇），將反射性、加工性 的任一個爲不合格的情況當作不合格（評價X )。 如表1中所示地，本發明的實施例之試料E 1〜試料E 1 2 皆顯示優異的反射性及加工性。 還有’上述試料E1〜試料12，由於預塗層3 (高反射 層4)的膜厚爲20〜140 μιη，故可薄壁輕量化。 再者’由於上述基礎樹脂42及高反射物質41係廉價， 而且可容易地形成上述預塗層3，故亦可減低製造成本。 如此地，若依照本例，能得到可薄壁輕量化、製造成 本減低、成形性及反射特性優異的高反射預塗之鋁合金板 〇 又，如由表1可知，比較例的試料C 1，雖然由於預塗 層（高反射層）的膜厚超過本發明.的上限，而反射率良好 ，但是加工性不合格。而且，製造成本增大。 還有，試料C2，由於預塗層的膜厚低於本發明的下限 ’故反射率顯著降低，反射性不合格。 再者，試料C3，由於高反射物質的平均粒徑低於本發 明的下限，故可見光容易穿透，反射率降低，反射性不合 格。 -17- 201105495 又’試料C4，由於高反射物質的含量低於本發明的下 限，故反射率降低，反射性不合格。 還有’試料C5，由於高反射物質的含量超過本發明的 較佳範圍之上限，故高反射物質由塗膜的脫落數容易增加 ’而且加工時在預塗層容易發生裂紋，加工性不合格。 再者’試料C6，由於高反射物質的平均粒徑超過本發 明的平均粒徑，故上述高反射物質由塗膜的脫落數容易增 加’而且加工時在預塗層容易發生裂紋，加工性不合格。 又’試料C7及試料C8，由於基礎樹脂的正反射降低率 超過本發明的上限，故樹脂所致的光吸收多，因此成爲全 反射率降低的原因，反射性不合格。 尙且，於本例中，上述預塗層3係僅形成在上述基板2 的一面，但是當然也可形成在上述基板的兩面。 又，於本例中，高反射物質爲單一種類，但是於組合 複數.種類的高反射物質時，亦可得到同樣的效果。 (實施例2 ) 本例係如圖3所示地，爲製作一種形成有由高反射層 402與底塗層6所層合成之預塗層3 02的高反射預塗之鋁合 金板1 02的例。 作爲構成上述底塗層6的底塗層用塗料，準備聚酯系 底漆。 對於與上述實施例1中所用基板相同之形成有鉻酸鹽 皮膜5的基板2，使用桿塗機在上述鉻酸鹽皮膜5上塗佈上 -18- 201105495 述底塗層用塗料。然後，於其上，使用桿塗機來塗佈相對 於100重量份的基礎樹脂（聚酯）而言含有150重量份的高 反射物質（氧化鈦）之塗料。之後，藉由在240 °C的烘箱 中烘烤60秒以使鋁表面的溫度成爲23 0°C而硬化，形成由 上述底塗層6及上述高反射層402所成的預塗層302，得到 高反射預塗之鋁合金板102。 上述底塗層6的膜厚爲5 μιη，上述高反射層402的膜厚 爲 4 0 μιη。 本例的高反射預塗之鋁合金板102，係與上述實施例1 中所得之高反射預塗之鋁合金板同樣地，可薄壁輕量化、 製造成本減低，成形性及反射特性優異》 (實施例3 ) 本例係如圖4所示地，爲製作一種形成有由第1高反射 層403與含內蠘43的第2高反射層404所成之預塗層303的高 反射預塗之鋁合金板1 03的例。 作爲上述內蠟43，準備巴西棕櫚蠟。 對於與上述實施例1中所用基板相同之形成有鉻酸鹽 皮膜5的基板2，使用桿塗機在上述鉻酸鹽皮膜5上塗佈相 對於100重量份的基礎樹脂42 (聚酯）而言含有150重量份 的高反射物質41 (氧化鈦）之塗料，然後使用桿塗機來塗 佈相對於100重量份的基礎樹脂42 (聚酯）而言含有60重 量份的高反射物質41 (氧化鈦）、2重量份的內蠟43之塗 料。之後，藉由在240°C的烘箱中烘烤60秒以使鋁表面的 -19- 201105495 溫度成爲2 3 0°C而硬化，形成由上述第1高反射層403及含 內蠟的第2高反射層404 (最外層）所成的預塗層3 03 ’得 到高反射預塗之鋁合金板1 。 上述第1高反射層403的膜厚爲40 μπι，最外層之上述第 2高反射層404的膜厚爲20μηι。 本例的高反射預塗之鋁合金板1〇3，由於在具有上述 高反射層403、404的預塗層303之最外層4 04中含有內蠟43 ，故可薄壁輕量化、製造成本減低，不僅成形性及反射特 性優異，而且具有良好的滑動性。 【圖式簡單說明】 圖1係顯示實施例1中的高反射預塗之鋁合金板之說明 圖。 圖2係顯示實施例1中的高反射層之機構的說明圖。 圖3係顯示實施例2中的高反射預塗之鋁合金板之說明 圖。 圖4係顯示實施例3中的高反射預塗之鋁合金板之說明 圖。 【主要元件符號說明】 1 :高反射預塗之鋁合金板 2 :基板 3 :預塗層 4 :高反射層 -20- 201105495 41 :高反射物質 42 :基礎樹脂 -21 -Comprehensive evaluation 〇〇〇〇〇〇〇〇〇〇〇〇XXXXXXXX Processability<1 <〇〇〇〇< 〇ο 0 〇< X 〇〇〇XX 〇〇Reflective evaluation〇〇〇〇〇〇 〇〇〇〇〇〇〇XXX 〇〇XX Total reflectance (%) CO 〇\ 〇\ 00 »η σ\ σ\ ν〇ON cn 00 荔Ον Ον ΓΟ σ\ ON Highly reflective substance content (parts by weight) t —Η 150 1—Η τ^Η ο ΓΟ 300 τ—Η 300 300 300 yn CA 350 r—Η Τ-Η τ-Η average particle size (μιη) Ο in ο 〇〇^Ti Ο Ο Ο ο Ο Ο r —< rH ο Τ—Η Ο Ο 0.06 · ο c5 in 〇iTi 〇 substance name titanium oxide titanium oxide titanium oxide titanium oxide titanium oxide titanium oxide titanium oxide barium sulfate barium sulfate titanium oxide titanium oxide titanium oxide titanium oxide Titanium oxide titanium oxide barium sulfate titanium oxide film thickness (μιη) ο 100 Ο 120 120 120 120 120 § ο rH Γ 120 120 ο (Ν r"H 〇<Ν regular reflection reduction rate (%) ^Ti IT) In Ό Ό Ο ΙΟ 〇ο CM base resin Polyester polyester polyester polyester polyester polyester 1 polyester polyester urethane urethane acrylate am fine κ polyester polyester polyester polyester urethane polyester polyester sample No. m CN W inch ω in ω Ό ω 00 ω m Ε10 Ell Ε12 Ο CN U cn U δ ΙΟ υ Ό U U U 00 U -15- 201105495 Next, for the obtained precoated aluminum alloy sheet 1, Evaluation of reflectivity and processability. <Reflective> The reflectivity was evaluated by measuring the total reflectance. The total reflectance was measured by using an integrating sphere spectrophotometer manufactured by Murakami Color Technology Research Institute. The total reflectance of the white plate to which the fine powder of barium sulfate was fixed was taken as 100%, and the measurement 値 of each sample at a wavelength of 550 nm was defined as total reflectance. In Table 1, there is no result. When the film thickness of the precoat layer 3 is ΙΟΟμηι or more, the case where the total reflectance is 95% or more is evaluated as 〇, and the case where the total reflectance is less than 95% is evaluated as X. Further, when the film thickness of the precoat layer 3 was less than ΙΟΟμπι, the case where the total reflectance was 88% or more was evaluated as 〇, and the case where the total reflectance was less than 88% was regarded as a defect, and it was represented by an X mark. Furthermore, the mechanism of the highly reflective layer 4 is shown in FIG. As shown in Fig. 2, the highly reflective layer 4 is such that the specific highly reflective substance 41 having a large refractive index is contained in a base resin 42 having light transmissivity in a specific amount, and has a specific film thickness. Then, since the light that has entered the precoat layer 3 (high reflection layer 4) penetrates the base resin 42 and is reflected at the interface between the base resin 42 and the highly reflective material 41, a high reflectance can be obtained. <Processability> The workability was evaluated by performing 90° bending and adhesion bending. When 90° is bent and tightly bent, no crack is observed on the coating film. The evaluation is 〇'. The case where only the bending is observed on the coating film is evaluated as △, and the bending is 90°. The case where the crack was observed on the coating film was evaluated as X, and the results are shown in Table i. The case where 评价 and △ were evaluated was regarded as pass, and the case where the evaluation was X was regarded as unacceptable. In addition, the comprehensive evaluation shown in Table 1 is regarded as a pass (evaluation) when both the reflectability and the workability are evaluated, and the case where either the reflectance or the workability is unacceptable is regarded as a failure ( Evaluation X). As shown in Table 1, the samples E 1 to E 1 2 of the examples of the present invention all exhibited excellent reflectivity and processability. Further, in the sample E1 to the sample 12 described above, since the film thickness of the precoat layer 3 (high reflection layer 4) is 20 to 140 μm, the thickness of the thin wall can be reduced. Further, since the base resin 42 and the highly reflective material 41 are inexpensive, and the precoat layer 3 can be easily formed, the manufacturing cost can be reduced. As described above, according to the present example, it is possible to obtain a highly reflective precoated aluminum alloy sheet which is thinner and lighter in weight, lower in production cost, and excellent in formability and reflection characteristics. As is apparent from Table 1, the sample C 1 of the comparative example is obtained. Although the film thickness of the precoat layer (high reflection layer) exceeded the upper limit of the present invention, the reflectance was good, but the workability was unacceptable. Moreover, manufacturing costs increase. Further, in the sample C2, since the film thickness of the precoat layer was lower than the lower limit of the present invention, the reflectance was remarkably lowered, and the reflectance was unacceptable. Further, in the sample C3, since the average particle diameter of the highly reflective substance is lower than the lower limit of the present invention, visible light is easily penetrated, the reflectance is lowered, and the reflectance is unqualified. -17- 201105495 In the sample C4, since the content of the highly reflective substance is lower than the lower limit of the present invention, the reflectance is lowered and the reflectivity is unacceptable. Further, in the sample C5, since the content of the highly reflective substance exceeds the upper limit of the preferred range of the present invention, the number of peeling off of the highly reflective substance by the coating film is easily increased, and cracking is likely to occur in the precoat layer during processing, and the workability is unacceptable. . Further, in the sample C6, since the average particle diameter of the highly reflective material exceeds the average particle diameter of the present invention, the number of peeling off of the highly reflective material by the coating film is likely to increase, and cracking is likely to occur in the precoat layer during processing, and the workability is not improved. qualified. Further, in the sample C7 and the sample C8, since the rate of decrease in the regular reflection of the base resin exceeds the upper limit of the present invention, the light absorption by the resin is large, so that the total reflectance is lowered, and the reflectance is unacceptable. Further, in the present embodiment, the precoat layer 3 is formed only on one surface of the substrate 2, but it may of course be formed on both surfaces of the substrate. Further, in the present embodiment, the highly reflective material is of a single type, but the same effect can be obtained when a plurality of types of highly reflective substances are combined. (Embodiment 2) This embodiment is shown in Fig. 3, in order to produce a highly reflective precoated aluminum alloy plate 102 formed with a precoat layer 032 composed of a highly reflective layer 402 and an undercoat layer 6. Example. As the coating material for the undercoat layer constituting the undercoat layer 6, a polyester primer was prepared. The substrate 2 on which the chromate film 5 was formed, which was the same as the substrate used in the above Example 1, was coated with the coating material for the undercoat layer on the chromate film 5 by a bar coater. Then, on the above, a bar coater was used to coat a coating containing 150 parts by weight of a highly reflective substance (titanium oxide) with respect to 100 parts by weight of the base resin (polyester). Thereafter, it is cured by baking in an oven at 240 ° C for 60 seconds to make the temperature of the aluminum surface become 23 ° C, thereby forming a precoat layer 302 formed by the undercoat layer 6 and the high reflection layer 402 described above. A highly reflective precoated aluminum alloy panel 102 is obtained. The undercoat layer 6 has a film thickness of 5 μm, and the high-reflection layer 402 has a film thickness of 40 μm. In the same manner as the high-reflection precoated aluminum alloy sheet obtained in the above-described first embodiment, the aluminum alloy sheet 102 of the high-reflection precoating of the present embodiment can be made thinner and lighter, and the manufacturing cost is reduced, and the moldability and the reflection property are excellent. (Embodiment 3) In this embodiment, as shown in Fig. 4, a high reflection pre-form is formed for forming a precoat layer 303 formed of a first high reflection layer 403 and a second high reflection layer 404 containing an inner crucible 43. An example of a coated aluminum alloy plate 103. As the inner wax 43, the carnauba wax is prepared. The substrate 2 on which the chromate film 5 was formed, which was the same as the substrate used in the above Example 1, was coated on the chromate film 5 with respect to 100 parts by weight of the base resin 42 (polyester) using a bar coater. A coating containing 150 parts by weight of the highly reflective substance 41 (titanium oxide), and then coated with a bar coater containing 60 parts by weight of the highly reflective substance 41 with respect to 100 parts by weight of the base resin 42 (polyester) ( Titanium oxide), 2 parts by weight of a coating of internal wax 43. Thereafter, it is baked by baking in an oven at 240 ° C for 60 seconds to cure the temperature of -19-201105495 of the aluminum surface to 2300 ° C, and the second high-reflection layer 403 and the second inner wax-containing layer are formed. The pre-coating 3 03 ' formed by the highly reflective layer 404 (outermost layer) gives a highly reflective precoated aluminum alloy sheet 1 . The first high-reflection layer 403 has a film thickness of 40 μm, and the outermost layer of the second high-reflection layer 404 has a film thickness of 20 μm. The highly reflective precoated aluminum alloy sheet 1〇3 of this example contains the inner wax 43 in the outermost layer 04 of the precoat layer 303 having the high reflection layers 403 and 404, so that the thin wall can be lightened and the manufacturing cost can be reduced. The reduction is excellent not only in formability and reflection characteristics, but also in good slidability. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an explanatory view showing a highly reflective precoated aluminum alloy sheet in the first embodiment. Fig. 2 is an explanatory view showing a mechanism of the highly reflective layer in the first embodiment. Fig. 3 is an explanatory view showing a highly reflective precoated aluminum alloy sheet in the second embodiment. Fig. 4 is an explanatory view showing a highly reflective precoated aluminum alloy sheet in the third embodiment. [Explanation of main component symbols] 1 : High-reflection pre-coated aluminum alloy plate 2 : Substrate 3 : Pre-coating 4 : High-reflection layer -20- 201105495 41 : Highly reflective substance 42 : Base resin -21 -