201142375 、發明說明： 【發明所屬之技術領域】 本發明是有關於一種偏光膜之製法及偏光板，特別是 指一種含有特殊水洗處理步驟之偏光膜之製法及含有此偏 光膜之偏光板。 【先前技術】 偏光板主要是由一偏光膜，以及利用接著劑貼合至該 偏光膜之至少一側的保護膜。用於偏光板之偏光膜主要係 使一親水性高分子之聚乙烯醇（p〇lyvinyl alc〇h〇l，pvA)系薄 膜經由拉伸、染色、交聯、水洗、乾燥等處理步驟所製成 。由於能源短缺問題的日益嚴重，各種電子裝置都希望朝 向節能方向去改善，就顯示器之偏光板而言，目前業界則 希望提高偏光板之單體透過率及偏光度，以及降低吸光度 等性質。 偏光板之性質的改善主要可針對偏光膜製程及後續貼 合製程的改善、接著劑的改良等方面進行。在眾多改善方 法中，以偏光膜製程的改善較符合環保與節能需求，例如 CN 101371172A之偏光膜製法，係、使聚乙婦醇系薄膜進行 拉伸、染色及交聯工序，最後進行清洗卫序，該清洗工序 是利用含有U0 wt%之醇及0.5〜10 wt%之碘化合物的水溶 液來進行。此專利需特別配製含有醇及魏合物之水溶液 ’尚？法符合環保之需求，且後續所獲得之偏光板的偏光 度至高僅達99.97%。 由上述說明可知’如能有效改善偏光膜之製程，將有 201142375 助於改善偏光板之性質， 望丄m 特別疋提昇單體透過率及偏光度 尊光學性質以及解決# ,θ 及赤變等問題，更可讓後續所製 传之偏光板符合業界之需求。 【發明内容】 因此，本發明之目的， 透過率及偏光度等光學性質 題之偏光膜之製法。 即在提供一種可有效提昇單體 ’更可解決染色色斑及赤變問BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polarizing film and a polarizing plate, and more particularly to a method for producing a polarizing film containing a special washing step and a polarizing plate comprising the polarizing film. [Prior Art] The polarizing plate is mainly composed of a polarizing film and a protective film adhered to at least one side of the polarizing film by an adhesive. The polarizing film for a polarizing plate is mainly made of a hydrophilic polymer polyvinyl alcohol (p〇lyvinyl alc〇h〇l, pvA) film by a processing step of stretching, dyeing, crosslinking, water washing, drying, and the like. to make. Due to the increasing shortage of energy, various electronic devices are hoping to improve toward energy saving. In the case of polarizers for displays, the industry is now hoping to improve the transmittance and polarization of the polarizing plates and to reduce the absorbance. The improvement of the properties of the polarizing plate can be mainly made for the improvement of the polarizing film process and the subsequent bonding process, and the improvement of the adhesive. Among the many improvement methods, the improvement of the polarizing film process is more in line with environmental protection and energy saving requirements. For example, the polarizing film manufacturing method of CN 101371172A is used to stretch, dye and crosslink the polyethylene glycol film, and finally to clean the bathroom. In this order, the cleaning step is carried out using an aqueous solution containing U0 wt% of an alcohol and 0.5 to 10 wt% of an iodine compound. This patent requires special preparation of an aqueous solution containing an alcohol and a Wei compound. The method meets the requirements of environmental protection, and the polarizing plate obtained in the subsequent period has a polarization degree of only 99.97%. It can be seen from the above description that if the process of polarizing film can be effectively improved, there will be 201142375 to help improve the properties of the polarizing plate, and it is particularly important to improve the monomer transmittance and the optical property of the polarizing degree and to solve #, θ and reddening. The problem is that the polarizers that are subsequently produced can meet the needs of the industry. SUMMARY OF THE INVENTION Accordingly, the object of the present invention is a method for producing a polarizing film of optical properties such as transmittance and polarization. That is to provide a kind of effective improvement of the monomer', which can solve the staining and reddening
本發明之另一 光板。 目的在於提供一種含有上述偏光膜之偏 ”於是，本發明偏光膜之製法包含：⑷使—聚乙稀醇系 4膜進行拉伸、染色及交聯處理；⑻使該經步驟⑷處理之 薄、進行至ν _人的水洗處理，該水洗處理是以溫度範圍 為9〜25。〇：之水清洗該經處理薄膜之兩側區域，同時以溫度 範圍為5〜14 C之水清洗該經處理薄膜之位於該兩側區域以 外的中央區域；及⑷使該經步驟⑻處理後之薄膜進行乾燥 ’以製得一偏光膜。Another light panel of the present invention. The object of the invention is to provide a polarizing film comprising the above-mentioned polarizing film. Thus, the method for producing a polarizing film of the present invention comprises: (4) stretching, dyeing and crosslinking the film of the polyvinyl alcohol-based film; (8) thinning the step (4). And performing a water washing treatment to the ν _ person, the water washing treatment is to wash the side of the treated film at a temperature ranging from 9 to 25. The water is washed with water having a temperature ranging from 5 to 14 C. Processing the film in a central region outside the two side regions; and (4) drying the film treated in the step (8) to obtain a polarizing film.
在偏光膜製作時，因為中央區域的膜厚較薄，且在後 續染色後，會讓中央區域的碘含量減少，因此中央區域較 易產生色斑；而兩側區域則因為延伸強度較差，對濕熱抵 抗力較弱，所以在乾燥加熱後，碘含量可能下降而容易發 生赤變現象。一般偏光膜製程大多在同一水溫下進行水洗 處理’並無法解決染色色斑及赤變等問題。為了有效解決 上述問題’本發明製法透過對經拉伸、染色及交聯之薄膜 的中央及兩側區域分別施予不同水溫並進行水洗處理，藉 201142375 此有效降低偏光膜產生色斑及赤變之機率，使得後續所製 得之偏光板具有不錯的單體透過率及偏光度，更讓偏光板 更符合業界需求。 【實施方式】 該步驟（a)可依據習知步驟進行染色、交聯及拉伸處理 〇 該步驟（b)之「兩側區域」係泛指接近薄膜之左右邊緣 的兩側區域，特別是經拉伸後較厚的區域。而「中央區域 」則為位在該兩側區域以外的其他區域，特別是指中央膜 厚較薄的區域。上述之「中央區域」及「兩側區域」可依 據實際施作狀況加以調整及改變。 較佳地，該步驟（c)之乾燥溫度範圍為4〇〜1〇〇CJC。更佳 地，該乾燥溫度範圍為50〜95。C。 本發明之偏光膜後續可依據習知偏光板的製程，進一 步製成一偏光板。 本發明之偏光板含有上述製法所製得之偏光膜。 較佳地，s亥偏光板具有高於42 7%之單體透過率。 較佳地，s亥偏光板具有高於99·99%之偏光度。 加熱30分鐘後，於波長 較佳地’該偏光板在l05〇c加熱 700 nm下之吸光度2 1.6。 一步說明，但應瞭解的 而不應被解釋為本發明 較佳地’該偏光板之色差為蕊12。 本發明將就以下實施例來作進一 d 是，該實施例僅為例示說明之用 實施之限制。 201142375 <實施例> I貫施例lj ⑷將厚75㈣之聚乙稀醇（平均聚合度為_，專化产為 "挪以上）單軸拉伸至乾燥狀態原尺寸（長度）的5~6倍 。將標開狀態的拉伸薄膜浸潰在染料溶液(依據破：举In the production of polarizing film, because the film thickness in the central region is thin, and after the subsequent dyeing, the iodine content in the central region is reduced, so the central region is more likely to produce stains; while the two regions are poor in elongation strength, The damp heat resistance is weak, so after drying and heating, the iodine content may decrease and the reddening phenomenon is likely to occur. In general, the process of polarizing film is mostly washed at the same water temperature, and the problem of staining and reddening cannot be solved. In order to effectively solve the above problems, the method of the present invention effectively treats the polarizing film to produce color spots and red by applying different water temperatures to the central and both sides of the stretched, dyed and crosslinked film, respectively, and performing water washing treatment. The chance of change makes the polarizing plate prepared in the future have a good single transmittance and polarization degree, which makes the polarizing plate more in line with the needs of the industry. [Embodiment] The step (a) can be dyed, cross-linked and stretched according to the conventional steps. The "two-sided area" of the step (b) generally refers to the two sides of the film which are close to the left and right edges of the film, especially Thicker areas after stretching. The "central area" is another area outside the two side areas, especially the area where the central film thickness is thin. The above-mentioned "central area" and "two-sided area" can be adjusted and changed according to the actual application conditions. Preferably, the drying temperature of the step (c) ranges from 4 〇 to 1 〇〇 CJC. More preferably, the drying temperature ranges from 50 to 95. C. The polarizing film of the present invention can be further formed into a polarizing plate in accordance with the process of the conventional polarizing plate. The polarizing plate of the present invention contains the polarizing film obtained by the above process. Preferably, the s-hai polarizing plate has a monomer transmittance higher than 42 7%. Preferably, the s-hai polarizing plate has a degree of polarization higher than 99.99%. After heating for 30 minutes, the absorbance of the polarizing plate at a wavelength of 100 μm at a wavelength of 20.5 〇c was 2 1.6. One step description, but should be understood, should not be construed as a preferred embodiment of the invention. The color difference of the polarizing plate is the core 12. The invention will be further described in the following examples, which are merely illustrative of the limitations of the embodiments. 201142375 <Examples> I Example 1j (4) The urethane of a thickness of 75 (four) (average degree of polymerization is _, the specialized yield is "over) is uniaxially stretched to the original size (length) of the dry state 5 to 6 times. Dip the stretched film in the open state in the dye solution (according to the break: lift
化卸：水=〇.〇5: 5:100之重量比例調製）内60秒，接 者再浸潰於㈣之硼酸處理溶液（依據蛾化卸：喊： 水= 2.5 : 7.5 : 1〇〇之重量比例調製）内3〇〇秒； ⑼然後依據下表i之水洗次數、中央區域水洗溫度及兩 側區域水洗溫度，對經步驟⑷處理之薄膜進行水洗處 理；及 ⑷使上述經步驟⑻處理後之薄膜於乾燥溫度為 40°C〜100°C之PVA乾燥爐中進行薄膜乾燥處理，最後 製得實施例1之偏光膜。 [實施例2~5】 除了依據下表1改變「水洗次數」、「中央區域水洗溫 度」及「兩側區域水洗溫度」之外，其餘製備方式及流程 皆與實施例1相同，最後分別製得實施例2〜5之偏光膜。 【比較例1〜4】 除了依據下表1改變「水洗次數」、「分區水洗溫度（即 中央區域水洗溫度及兩側區域水洗溫度）」或「不分區水洗 溫度」之外，其餘製備方式及流程皆與實施例1相同，最 後分別製得比較例1〜4之偏光膜。 201142375 表1 水洗次數 分區水洗溫度(°c) 不分區水洗溫度(。〇 中央區域 兩側區域 實施例1 3 10 15 / 實施例2 3 14 25 實施例3 1 5 15 實施例4 1 5 9 實施例5 1 13 18 比較例1 3 18 比較例2 3 16 19 比較例3 1 5 比較例4 1 13 [測試】 分別於上述實施例1〜5及比較例1~4之偏光膜的上下 兩面塗佈一接著劑（含有聚乙烯醇樹脂及交聯劑，其中，該 交聯劑係擇自於二醛類），以於該偏光膜的上下表面分別形 成一接著層。接著’於該兩接著層上分別貼合一層厚度 80μπι且由三乙醯基纖維素所構成之保護層以及一層厚 70μηι且由環烯烴共聚物所構成之保護層，再於貼合乾燥爐 中進行一貼合乾燥（貼合乾燥的溫度為40cC)，以分別製得 一偏光板。 再使上述實施例1〜5及比較例1〜4分別製得之偏光板 進行以下測試’測試結果如下表2所示： U)單體透過率（％)··利用配置有積分球之分光光度計（曰本 201142375 分光株式會社製造，型號為v_7100)進行測試。目前業 界可接受之單體透過率為高於42%。 (2) 偏光度:利用配置有積分球之分光光度計進行測試 。目前業界可接受之偏光度為g 99,99%。 (3) 色差（ΔΕ广為國際照明委員會（intemati〇nal c〇mmissi〇n on illuminati〇n，CIE)所提出用以定義一 αΕ p ^於 (CIELAB)之色彩空間所採用的標準，其三個基本坐標 (ΖΛ α*，6*)分別表示顏色的亮度: £*=〇指示黑色， 而[*=100指示白色），以及顏色在紅色和綠色之間的位 置（α*為負值指示趨向綠色，而正值指示趨向紅色）和顏 色在黃色和藍色之間的位置（b*負值指示趨向藍色而 正值指示趨向黃色）。本發明利用光度計（由日本分光株 式會社製造，型號為V_71〇〇)測試所製得之各偏光板所 呈現之色相所具有之“與色度值，再代入公式 Μ = λ/(Δ^)2+(Δα)2+(Δό)2，即分別獲得色差值。 (4) 染色色斑：利用肉眼目視所製得之偏光板，並進行評 4貝，6平價等級為：「〇」表示幾乎無色斑；「△」表示 有少數但不影響後續效能之色斑；Γχ」表示有多塊色 斑°「0」及「^」為業界可接受之範圍。 (5) 加熱後於700 nm之吸光度：分別使上述所製得之偏光 板於105〇C下加熱30分鐘，接著再利用紫外線吸收儀（ 曰本分光株式會社製造，型號為v_71〇〇)測試吸光度。 (6) 加熱後之赤變狀況：由上述測試（5)之吸光度進行評價 ，砰價等級為「〇」表示吸光度為>2;「八」表示吸 201142375 光度為1.6〜2;「x」表示吸光度為<16。「〇」及「八 」為業界可接受之範圍。 單體 透過率(％) 偏光度 (%) 色差 ΛΕ 實施例1 42.82 99.9965 1.2 加熱後700nm 吸光度 染色 加熱後 赤變 1.71 色斑Discharge: water = 〇. 〇 5: 5:100 weight ratio modulation) within 60 seconds, the receiver is then immersed in the (b) boric acid treatment solution (according to the moth unloading: shout: water = 2.5: 7.5: 1 〇〇 The weight ratio is adjusted within 3 sec.; (9) and then the water treated by the step (4) is subjected to a water washing treatment according to the number of times of washing in the following table i, the water washing temperature in the central region, and the water washing temperature in the both sides; and (4) the above step (8) is performed. The treated film was subjected to film drying treatment in a PVA drying oven having a drying temperature of 40 ° C to 100 ° C, and finally the polarizing film of Example 1 was obtained. [Examples 2 to 5] The preparation methods and procedures are the same as those in the first embodiment except that the "washing frequency", "central area washing temperature" and "two-side area washing temperature" are changed according to the following Table 1. The polarizing films of Examples 2 to 5 were obtained. [Comparative Examples 1 to 4] In addition to changing the "washing frequency", "divisional washing temperature (ie, central area washing temperature and water washing temperature on both sides)" or "non-partitioned washing temperature" according to the following Table 1, the other preparation methods and The procedure was the same as in Example 1, and finally, the polarizing films of Comparative Examples 1 to 4 were separately produced. 201142375 Table 1 Washing times Partition washing temperature (°c) Non-partitioning washing temperature (.〇 Both sides of the central area Example 1 3 10 15 / Example 2 3 14 25 Example 3 1 5 15 Example 4 1 5 9 Implementation Example 5 1 13 18 Comparative Example 1 3 18 Comparative Example 2 3 16 19 Comparative Example 3 1 5 Comparative Example 4 1 13 [Test] The upper and lower surfaces of the polarizing films of the above Examples 1 to 5 and Comparative Examples 1 to 4 were respectively coated. a cloth-based adhesive (containing a polyvinyl alcohol resin and a crosslinking agent, wherein the crosslinking agent is selected from a dialdehyde) to form an adhesive layer on the upper and lower surfaces of the polarizing film, respectively. A protective layer composed of triacetyl cellulose and a protective layer composed of a cyclic olefin copolymer having a thickness of 80 μm and a thickness of 70 μm are respectively adhered to the layer, and then subjected to a bonding drying in a bonding drying oven ( The temperature of the bonding and drying was 40 cC to prepare a polarizing plate. The polarizing plates prepared in the above Examples 1 to 5 and Comparative Examples 1 to 4 were subjected to the following tests. The test results are shown in Table 2 below: U ) Monomer transmittance (%)··With configuration, there are points The ball spectrophotometer (manufactured by Sakamoto 201142375, Ltd., model v_7100) was tested. The monomer permeability currently accepted by the industry is higher than 42%. (2) Polarization: Tested using a spectrophotometer equipped with an integrating sphere. The industry currently accepts a degree of polarization of g 99,99%. (3) Chromatic aberration (ΔΕ广 is the standard adopted by the International Commission on Illumination (intemati〇nal c〇mmissi〇n on illuminati〇n, CIE) to define a color space of αΕ p ^ in (CIELAB), three The basic coordinates (ΖΛ α*, 6*) indicate the brightness of the color: £*=〇 indicates black, and [*=100 indicates white), and the position of the color between red and green (α* is negative) It tends to green, while positive values indicate a tendency to red) and the color is between yellow and blue (b* negative values indicate a trend toward blue and positive values indicate a trend toward yellow). The present invention uses a photometer (manufactured by JASCO Corporation, model number V_71〇〇) to test the hue value of each of the polarizing plates obtained by the test, and then enters the formula Μ = λ/(Δ^ 2+(Δα)2+(Δό)2, that is, the color difference values are respectively obtained. (4) Staining stain: The polarizing plate obtained by visual inspection by the naked eye is evaluated, and the rating of 6 is: "〇 "There is almost no stain; "△" means that there are a few stains that do not affect the subsequent performance; "" indicates that there are many stains "0" and "^" are acceptable for the industry. (5) Absorbance at 700 nm after heating: The polarizing plate prepared above was heated at 105 ° C for 30 minutes, and then tested by an ultraviolet absorber (manufactured by Sakamoto Seiko Co., Ltd., model: v_71〇〇) Absorbance. (6) Reddening condition after heating: evaluated by the absorbance of the above test (5), the price level of "砰" means absorbance is >2; "eight" means that absorbance of 201142375 is 1.6~2; "x" Indicates that the absorbance is <16. "〇" and "八" are acceptable to the industry. Monomer Permeability (%) Polarization (%) Color Difference 实施 Example 1 42.82 99.9965 1.2 700nm absorbance after heating Dyeing After heating, reddening 1.71
在表2中，可知實施例丨〜5所製得之偏光膜在後續製 成偏光板後，具有42.7%以上之單體透過率、99 99%以上之 偏光度、1.2以下之色差及在加熱後仍具有16以上之吸光 度，且幾乎不會產生染色色斑及赤變問題，證明本發明之 偏光膜的製法確實可有效提昇偏光板之光學性質，更可解 決染色色斑及赤變問題。 將實施例1與比較例1之結果進行比較，可發現實施 例1之染色色斑及赤變問題皆屬於業界接受之範圍，但是 比較例1之偏光板卻有嚴重的染色色斑問題（比較例2及4 中亦有相同問題’而比較例3則出現赤變問題）’證實本發 10 201142375 明製法經由分區施予不同水溫清洗之步驟，確實可同時解 決染色色斑及赤變問題。 另將實施例2及比較例2之結果進行比較，可發現比 較例2會產生染色色斑問題，主要因素為中央區域：水溫 為16°C，可見中央區域及兩側區域之水溫範圍須特別控制 ，且由實施例1〜5之結果，可知中央區域水溫需控制在 5〜14°C，而兩側區域之水溫則需控制在9〜25〇c：。 表 τ、上所述’本發明製法透過對經拉伸、染色及交聯後 ® 之薄膜的中央及兩側區域分別施予不同水溫範圍之水洗處 理’有效地提昇偏光板之光學性質，並可解決染色色斑及 赤變問題。 惟以上所述者’僅為本發明之較佳實施例而已，當不 此以此限定本發明實施之範圍，即大凡依本發明申請專利 範圍及發明說明内容所作之簡單的等效變化與修飾，皆仍 屬本發明專利涵蓋之範圍内。 【圖式簡單說明】 201142375 【主要元件符號說明】 無In Table 2, it is understood that the polarizing film obtained in Examples 丨 to 5 has a monomer transmittance of 42.7% or more, a polarization degree of 99 99% or more, a color difference of 1.2 or less, and heating under a polarizing plate. After that, it still has an absorbance of 16 or more, and hardly produces staining spots and reddening problems. It proves that the method for producing the polarizing film of the present invention can effectively improve the optical properties of the polarizing plate, and can solve the problem of staining and reddening. Comparing the results of Example 1 with Comparative Example 1, it can be found that the staining and reddening problems of Example 1 are within the accepted range of the industry, but the polarizing plate of Comparative Example 1 has a serious staining problem (Comparative The same problem was also found in Examples 2 and 4, and the reddening problem occurred in Comparative Example 3. 'Confirming that the method of applying the different water temperature cleaning by the method of the Mingfa 10 201142375 can solve the problem of staining and reddening at the same time. . Comparing the results of Example 2 and Comparative Example 2, it can be found that the dyeing stain problem occurs in Comparative Example 2. The main factor is the central region: the water temperature is 16 ° C, and the water temperature range of the central region and the two sides is visible. It must be specially controlled, and from the results of Examples 1 to 5, it can be known that the water temperature in the central region should be controlled at 5 to 14 ° C, and the water temperature in the two regions should be controlled at 9 to 25 ° C:. Table τ, the above-mentioned method of the present invention effectively improves the optical properties of the polarizing plate by applying a water washing treatment to the central and both sides of the film which is stretched, dyed and cross-linked, respectively, to different water temperature ranges. It can solve the problem of staining and reddening. However, the above description is only a preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent change and modification of the patent application scope and the description of the invention. All remain within the scope of the invention patent. [Simple description of the schema] 201142375 [Explanation of main component symbols]
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