1288066 (1) 玖、發明說明 【發明所屬之技術領域】 本發明係有關構成液晶顯示板之液晶元件光源側表面 上進行黏貼層合之層合偏光薄膜的製造方法。 【先前技術】 如圖1所示，構成液晶顯示板之液晶元件光源側表面 上黏貼直線偏光薄膜。亦即，液晶元件10之光源側表面上 ，藉由黏著劑層12被黏貼層合直線偏光薄膜14，構成液晶 顯示板者。液晶顯示板逐年被要求更鮮明之影像，更減少 光源消耗電力者。因此，爲減少液晶顯示板之光源消耗電 力，有效利用光源之光爲目的下，一直被使用於直線偏光 薄膜之光源側暫時反射未平行於直線偏光薄膜之透光軸的 光，藉由另設置反射板使再度可透過反射光之直線偏光分 離薄膜進行黏貼層合之層合偏光薄膜者。此層合偏光薄膜 現狀再大亦不過1邊爲150cm左右。 圖2係代表層合偏光薄膜1 8之構成例者。直線偏光薄 膜20與直線偏光分離薄膜22係介著黏著劑層24被黏貼層合 者。於直線偏光薄膜20之另一面設置爲黏著層合偏光薄膜 於液晶元件之黏著劑層26以及保護該黏著劑層26之剝離薄 膜層28。且，直線偏光分離薄膜之反面被層合保護薄膜30 者。保護薄膜30於最終步驟被剝離去除之。 具有該構成之層合偏光薄膜係藉由黏著劑層合直線偏 光薄膜與直線偏光分離薄膜之步驟所製造者。（如：特開 -4- (2) 1288066 平11-271534號公報（段落〔0005〕~〔 0007〕及特開 2000-275436號公報（段落〔 0034〕）。 惟，放置該步驟取得之層合偏光薄膜後，黏貼於液晶 元件側之直線偏光薄膜側（圖2之A面側）產生凹陷之卷 縮（以下稱「逆卷縮」。），此逆卷縮其層合偏光薄膜之 1邊爲8cm以上，特別爲20cm以上最爲明顯。該大逆卷縮 於剝離剝離薄膜28後，黏貼於液晶元件10時，易殘留氣泡 於黏著面，產生不良液晶板之原因。 因此，該層合偏光薄膜被要求實質上未產生逆卷縮、 未卷縮、或即使卷縮，其直線偏光薄膜側亦呈凸卷縮（以 下稱「正卷縮」）者。 【發明內容】 本發明之目的係爲提供一種未產生實質之逆卷縮的層 合偏光薄膜製造方法者。 本發明者爲達成該目的，進行精密硏討取得未產生實 質逆卷縮之層合偏光薄膜後，發現調整直線偏光分離薄膜 之水分率於一定範圍下，藉由層合直線偏光薄膜後，可取 得未產生逆卷縮之層合偏光薄膜者，進而完成本發明。 亦即，本發明係層合直線偏光薄膜與直線偏光分離薄 膜之製造層合偏光薄膜的方法者。 其特徵係於層合前，具有調整直線偏光分離薄膜之水 分率爲0.3~0.8重量％之水分率調整步驟者。 藉由本發明方法後，可取得實質上無逆卷縮之層合偏 (4) 1288066 上述本發明中該直線偏光分離薄膜爲聚酯薄膜者宜。 直線偏光分離薄膜以聚酷做爲主成份之薄膜者宜，特 別是以聚乙細萘一甲酸醋、聚乙稀萘二甲酸酯單位做爲主 成份之共聚物做爲原料之薄膜者其性能上爲較佳者，如： 做爲商品名「DBEF」（住友3M公司）被市販者之例。此 聚酯所組成之直線偏光分離薄膜於製造後，直接做爲坏體 卷取後供給之，因此，坏體薄膜之水分率其實測後爲 0·1〜0.2重量％者，低於其薄膜之飽和水分率（約〇.8重 量％ )，與高水分率之直線偏光薄膜進行層合時藉由水份 之移動更易出現逆卷縮。 又，直線偏光分離薄膜如上述，透過平行透光軸方向 之光後，具有與透光軸交叉之平行反射軸方向之光進行反 射機能之薄膜者、反射型偏光薄膜、非吸收型偏光薄膜、 或被反射之光進行再利用後提昇亮度，因此，亦稱亮度提 昇薄膜者。 另外，針對此直線偏光薄膜透過平行透光軸方向之光 後，具有與透光軸交叉之平行吸收軸方向光之吸收機能薄 膜者，亦稱吸收型偏光薄膜。 直線偏光薄膜係使用公知之直線偏光薄膜者。直線偏 光薄膜一般以三乙醯纖維素（TAC )薄膜做爲主材料所構 成者，較理想之構成爲TAC薄膜與聚乙烯醇系薄膜相互 之層合薄膜，具體例如：至少具有3層TAC薄膜/聚乙烯 醇系薄膜/TAC薄膜之構成例者。構成此等直線偏光薄膜 之樹脂材料均爲高極性、高飽和水分率之材料者。一般使 (5) 1288066 用如上記之多層結構之直線偏光薄膜由於抑制其自體之卷 縮而水分率較高，被調整於2.5重量％者。爲此，藉由與 乾燥狀態之聚酯系直線偏光分離薄膜之層合後，水份由直 線偏光薄膜移行至直線偏光分離薄膜後，出現卷縮。 藉由設定調整直線偏光分離薄膜之水分率的水分率調 整步驟後，所取得層合偏光薄膜不易出現逆卷縮之理由仍 未明朗，惟，依水份由高水分率直線偏光薄膜往低水分率 之直線偏光分離薄膜移行後其各薄膜之尺寸變化被控制者 爲其一大主因可被推斷之。 通常，於直線偏光分離薄膜之一面被層合由聚乙烯對 苯二甲酸酯等所成之保護薄膜。直線偏光薄膜被層合於層 合此保護薄膜面之反面。保護薄膜係黏著於液晶元件後， 被剝離去除者。 【實施方式】 〔實施例〕 以下，針對具體所示之實施例等進行說明本發明之構 成與效果。 另外，卷縮量係將直線偏光薄膜側向下，置於平板上 ，求出由層合偏光薄膜四頂點平板之高度平均値。+代表 正卷縮、-代表逆卷縮。 (實施例1 ) 將厚度132 μπι之聚乙烯萘二甲酸酯製之直線偏光分離 (6) 1288066 薄膜「DBEF」（住友3M公司製’另一面層合聚乙烯萘二 甲酸酯之保護薄膜，水分率：約0.2重量％ )切成308mm X 235mm取5片備用，分別於相對濕度8〇%，溫度2〇 f之環 境下放置2 4小時。放置後水分率爲〇 . 6 2重量％ (水分率 於剝離保護膜下進行測定者）。此直線偏光分離薄膜立刻 置入防濕袋進行密封，2小時後取出，於未層合保護薄 膜面層合直線偏光薄膜後，取得層合偏光薄膜。層合時使 用黏著滾輥者。 所使用直線偏光薄膜其水分率約爲2.5重量％，具有 TAC /聚乙嫌醇系薄膜 /TAC ( 80 μιηχ25 μιηχ80 μιη)之 3 層結構，具25 μιη丙嫌系感壓型黏著劑層者。 將取得層合偏光薄膜置入防濕袋後進行密封，20 °C 下經過表1所示時間之後取出測定卷縮量。卷縮量之測定 結果如表1所不。 (實施例2 ) 於相對濕度64%，溫度22 °C之環境下放置直線偏光 分離薄膜「DBEF」24小時。放置後之水分率爲0·50重 量％ (水分率於剝離保護膜下進行測定者）。除使用此直 線偏光分離薄膜之外，與實施例1同法製成層合偏光薄膜 〇 將取得層合偏光薄膜置入防濕袋進行密封，20 °C下 經過表1所示之時間後，取出測定卷縮量。測定結果如表1 所示。 -9- 12880661288066 (1) Technical Field of the Invention The present invention relates to a method for producing a laminated polarizing film which is adhered and laminated on a light source side surface of a liquid crystal element constituting a liquid crystal display panel. [Prior Art] As shown in Fig. 1, a linear polarizing film is adhered to the surface of the light source side of the liquid crystal element constituting the liquid crystal display panel. That is, on the light source side surface of the liquid crystal element 10, the linear polarizing film 14 is adhered by the adhesive layer 12 to constitute a liquid crystal display panel. Liquid crystal display panels are required to produce more vivid images every year, and to reduce the power consumption of light sources. Therefore, in order to reduce the power consumption of the light source of the liquid crystal display panel and effectively use the light of the light source, the light source side of the linear polarizing film is always used to temporarily reflect the light that is not parallel to the transmission axis of the linear polarizing film, and is additionally provided. The reflecting plate is a laminated polarizing film which is adhered to the linear polarizing separation film which is again permeable to the reflected light. The current situation of this laminated polarizing film is as large as about 150 cm on one side. Fig. 2 is a view showing a configuration example of the laminated polarizing film 18. The linear polarizing film 20 and the linear polarizing separation film 22 are adhered to each other via the adhesive layer 24. The other surface of the linear polarizing film 20 is provided with an adhesive layer 26 for adhering the polarizing film to the liquid crystal element and a release film layer 28 for protecting the adhesive layer 26. Further, the reverse side of the linear polarization separation film is laminated with the protective film 30. The protective film 30 is peeled off at the final step. The laminated polarizing film having such a structure is produced by a step of laminating a linear polarizing film and a linear polarized light separating film by an adhesive. (e.g., Japanese Patent Publication No. 4-(2) No. 1288066, No. Hei 11-271534 (paragraphs [0005] to [0007] and JP-A-2000-275436 (paragraph [0034]). After the polarizing film is bonded, the side of the linear polarizing film on the side of the liquid crystal element (on the side of the A side of FIG. 2) is entangled (hereinafter referred to as "reverse crimping"), and the laminated film of the polarizing film is reversely crimped. The side is 8 cm or more, and particularly 20 cm or more. The large reverse shrinkage of the peeling and peeling film 28 causes adhesion of bubbles to the adhesive surface, resulting in a defective liquid crystal panel. The polarizing film is required to have substantially no crimping, unrolling, or curling, and the linear polarizing film side is also convexly crimped (hereinafter referred to as "positive crimping"). The object of the invention is to provide a method for producing a laminated polarizing film which does not produce substantial reverse crimping. In order to achieve the object, the inventors of the present invention have conducted a precise beating to obtain a laminated polarizing film which does not cause substantial reverse crimping, and found an adjustment straight line. Polarized separation film When the moisture content is within a certain range, by laminating the linear polarizing film, a laminated polarizing film which does not cause reverse crimping can be obtained, and the present invention is completed. That is, the present invention is a laminated linear polarizing film and linearly polarized light separation. A method for producing a laminated polarizing film for a film is characterized in that it has a water content adjustment step of adjusting a moisture content of a linear polarization separation film of 0.3 to 0.8% by weight before lamination. By the method of the present invention, substantial The laminate without reverse shrinkage is biased (4) 1288066. The linear polarized light separation film of the present invention is preferably a polyester film. The linear polarized light separation film is preferably a film based on polycool as a main component, especially polyethylene. A fine naphthalene-formic acid vinegar or a polyethylene naphthalate unit is used as a raw material as a raw material film, and its performance is preferred, such as: as the trade name "DBEF" (Sumitomo 3M) As a case of a market trader, the linear polarized light separation film composed of the polyester is directly supplied as a bad body after being wound up, and therefore, the moisture content of the bad body film is actually 0.1 to 0.2% by weight. By , which is lower than the saturated moisture content of the film (about 8% by weight), and is more likely to be reversely curled by the movement of moisture when laminating the linearly polarizing film having a high moisture content. Further, the linearly polarizing separation film is as described above. After passing through the light in the direction of the parallel transmission axis, the light having the parallel reflection axis direction intersecting the transmission axis is used as a film for reflecting function, a reflective polarizing film, a non-absorptive polarizing film, or a reflected light for reuse. After that, the brightness is increased, so that it is also called a brightness enhancement film. In addition, after the linear polarizing film passes through the light in the direction parallel to the transmission axis, the absorption film having the parallel absorption axis direction crossing the transmission axis is also called Absorptive polarizing film. The linear polarizing film is a known linear polarizing film. The linear polarizing film is generally composed of a triacetyl cellulose (TAC) film as a main material, and is preferably a laminated film of a TAC film and a polyvinyl alcohol film, for example, at least three layers of TAC film. / The structure of the polyvinyl alcohol film / TAC film. The resin materials constituting these linear polarizing films are all materials having high polarity and high saturated moisture content. In general, (5) 1288066 is a linear polarizing film having a multilayer structure as described above, which has a high moisture content due to suppression of its self-winding, and is adjusted to 2.5% by weight. For this reason, after laminating with the polyester-based linear polarized light separation film in a dry state, the moisture migrates from the linear polarizing film to the linear polarized light separation film, and curling occurs. After setting the moisture rate adjusting step of adjusting the moisture content of the linear polarizing separation film, the reason why the obtained laminated polarizing film is less likely to be reversely curled is still unclear, but the moisture is changed from the high moisture ratio linear polarizing film to the low moisture. The change in the size of each film after the linear polarized light separation film is transferred can be inferred by the controller. Usually, a protective film made of polyethylene terephthalate or the like is laminated on one side of the linear polarized light separation film. The linear polarizing film is laminated on the reverse side of the laminated protective film surface. After the protective film is adhered to the liquid crystal element, it is peeled off. [Embodiment] [Embodiment] Hereinafter, the configuration and effects of the present invention will be described with respect to specific examples and the like. Further, the amount of crimping was such that the linear polarizing film side was placed downward on the flat plate, and the height average 値 of the four-apex flat plate of the laminated polarizing film was determined. + stands for positive curling, - stands for reverse curling. (Example 1) Linear polarized light separation of polyethylene naphthalate having a thickness of 132 μm (6) 1288066 Film "DBEF" (manufactured by Sumitomo 3M Co., Ltd.) Protective film of another surface laminated polyethylene naphthalate , Moisture rate: about 0.2% by weight) Cut into 308mm X 235mm Take 5 pieces of spare, and place them in an environment of relative humidity of 8〇% and temperature of 2〇f for 24 hours. The moisture content after standing was 〇6.2% by weight (the moisture content was measured under a peeling protective film). The linear polarized separation film was immediately placed in a moisture-proof bag for sealing, and taken out after 2 hours, and a linear polarizing film was laminated on the unlaminated protective film surface to obtain a laminated polarizing film. Use adhesive roller when laminating. The linear polarizing film used had a moisture content of about 2.5% by weight, and had a three-layer structure of TAC / polyethyl alcohol film / TAC (80 μm χ 25 μιη χ 80 μιη), and a layer of 25 μM sensitizing pressure-sensitive adhesive layer. The laminated polarizing film was placed in a moisture-proof bag, sealed, and the amount of crimping was taken out after passing the time shown in Table 1 at 20 °C. The measurement results of the amount of crimping are as shown in Table 1. (Example 2) A linear polarized separation film "DBEF" was placed in an environment having a relative humidity of 64% and a temperature of 22 ° C for 24 hours. The moisture content after standing was 0.50% by weight (the moisture content was measured under a peeling protective film). A laminated polarizing film was produced in the same manner as in Example 1 except that the linear polarizing separation film was used. The laminated polarizing film was placed in a moisture-proof bag and sealed, and after passing the time shown in Table 1 at 20 ° C, Take out the measured curl amount. The measurement results are shown in Table 1. -9- 1288066
(比較例1 ) 將厚度132 μπι之直線偏光分離薄膜「DBEF」（水分 率〇·17重量％)切成308mmx2 3 5mm取5片備用，置於相對 濕度24%，溫度22 °C之環境下24小時，水分率仍呈〇·17 重量％ (水分率於剝離保護薄膜下進行測定者）。 以該水分率〇. 1 7重量％之薄膜做爲直線偏光分離薄 膜使用之外，與實施例1同法製成層合偏光薄膜。 將取得層合偏光薄膜置入防濕袋進行密封後，20 °C 下經過表1所示時間後取出進行測定卷縮量。卷縮量之測 疋結果如表1所不。 〔表1〕 實施例1 實施例2 比較例1 水分率（wt%) 0.62 0. 50 0.1 7 經過時 間 (hr) 0 0.5 0.3 0.0 13 9.1 3.8 -4.7 23 9.6 4.5 -5.0 85 9.7 4.9 -4.3 253 8.9 4.0 -3.6 由表1結果顯示，直線偏光分離薄膜進行加濕後，調 整水分率之後’層合直線偏光薄膜之本發明層合偏光薄膜 均呈正卷縮’與液晶元件相互黏貼時，呈未產生氣泡之良 品，惟，未設定水分率調整步驟之比較例層合偏光薄膜則 10 (8) 1288066 產生逆卷縮。 (實施例3 ) 利用圖3所示之加濕裝置進行調整直線偏光分離薄膜 之水分率。於附保護薄膜之狀態下以一定速度連續性使直 線偏光分離薄膜進行走行之同時，將水份噴霧於保護薄膜 後附著之後，直接卷取於另一蕊心。變更薄膜之走行速度 ，改變水份附著量。卷取薄膜滾筒靜置2天後，取得調整 水分率之直線偏光分離薄膜。 剝離直線偏光分離薄膜之保護薄膜後，進行測定水分 碑< 〇 將取得水分率調整過之直線偏光分離薄膜立刻置入防 濕袋進行密封，2小時後取出後與實施例1同法層合直線 偏光薄膜於未層合保護薄膜之面，取得20inch尺寸（ 420mmx318mm)之層合偏光薄膜。 取得之層合偏光薄膜置入防濕袋後進行密封後，20 °C下經過65小時取出後，測定卷縮量。卷縮量之測定結 果如表2所示。 11 (9) 1288066 〔表2〕 水分率 (wt %) 卷縮値（mm) (貼合後65Hrs) 外觀 使用之可否 1 0.30 -1.4 良 可 實施例3 2 0.42 + 0.4 良 可 3 0.61 + 5.8 良 可 4 0.73 + 13.9 良 可 水分率爲0.30重量％時，卷縮量爲-1.4mm，些許逆 卷縮而爲容許範圍者，所取得層合偏光薄膜可安心使用之 〔發明效果〕 本發明方法於黏著液晶元件時，可取得黏著面殘留氣 泡，產生不良液晶板原因之實質上未產生逆卷縮之直線偏 光薄膜與直線偏光分離薄膜所成之層合偏光薄膜者。 【圖式簡單說明】 〔圖1〕 代表於液晶元件層合偏光薄膜結構之截面圖。 〔圖2〕 代表層合偏光薄膜結構之截面圖。 〔圖3〕 連接於直線偏光分離薄膜後，噴霧水霧後進行加濕裝 ·-12 - (10) 1288066 置之槪略 【符號說 10 ： 12 ： 14 ： 18 : 20 ： 22 ： 24 : 26 ： 28 ： 30 ： 32 ： 34 ： 圖。 明】 液晶元件 黏著劑層 直線偏光薄膜 積層偏光薄膜 直線偏光薄膜 直線偏光分離薄膜 黏著劑層 黏著劑層 剝離薄膜 保護薄膜 薄膜送出滾輥 薄膜捲取滾輥 36 :重霧噴霧裝置(Comparative Example 1) A linear polarized light separation film "DBEF" (water content 〇·17% by weight) having a thickness of 132 μm was cut into 308 mm x 2 3 5 mm, and 5 sheets were taken for use, and placed in a relative humidity of 24% and a temperature of 22 ° C. The moisture content was still 〇17% by weight for 24 hours (the moisture content was measured under a peeling protective film). A laminated polarizing film was produced in the same manner as in Example 1 except that the film having a water content of 1.7 wt% was used as the linear polarized light separation film. The laminated polarizing film was placed in a moisture-proof bag and sealed, and then taken out at 20 ° C for the time shown in Table 1, and then taken out to measure the curl amount. The measurement of the amount of crimping is shown in Table 1. [Table 1] Example 1 Example 2 Comparative Example 1 Moisture content (wt%) 0.62 0. 50 0.1 7 Elapsed time (hr) 0 0.5 0.3 0.0 13 9.1 3.8 -4.7 23 9.6 4.5 -5.0 85 9.7 4.9 -4.3 253 8.9 4.0 -3.6 The results in Table 1 show that after the linear polarizing separation film is humidified, after adjusting the moisture content, the laminated polarizing film of the present invention which is laminated with a linear polarizing film is positively crimped, and when the liquid crystal elements are adhered to each other, The good result of the bubble generation, but the comparative example laminated light film which does not set the moisture rate adjustment step, 10 (8) 1288066 produces a reverse crimp. (Example 3) The moisture content of the linearly polarized light separation film was adjusted by the humidifying device shown in Fig. 3. The linear polarized light separation film is continuously conveyed at a constant speed in a state of a protective film, and the water is sprayed on the protective film and attached, and then directly taken up to the other core. Change the speed of the film and change the amount of moisture attached. After the film roll was taken up for 2 days, a linear polarized light separation film having a moisture content adjusted was obtained. After peeling off the protective film of the linear polarizing separation film, the moisture recording was measured. The linear polarizing separation film whose moisture content was adjusted was immediately placed in a moisture-proof bag and sealed, and after 2 hours, it was laminated in the same manner as in Example 1. A linear polarizing film was obtained on the surface of the unlaminated protective film to obtain a 20-inch (420 mm x 318 mm) laminated polarizing film. The obtained laminated polarizing film was placed in a moisture-proof bag, sealed, and taken out at 20 ° C for 65 hours, and then the amount of curl was measured. The measurement results of the crimp amount are shown in Table 2. 11 (9) 1288066 [Table 2] Moisture content (wt %) Curl 値 (mm) (65Hrs after bonding) Appearance can be used 1 0.30 -1.4 Good example 3 2 0.42 + 0.4 Good 3 0.61 + 5.8良 可 4 0.73 + 13.9 When the moisture content is 0.30% by weight, the amount of crimping is -1.4 mm, and the amount of crimping is somewhat tolerated, and the obtained laminated polarizing film can be used with ease. In the method of adhering a liquid crystal element, a residual polarizing film on the adhesive surface can be obtained, and a laminated polarizing film formed by a linear polarizing film and a linear polarizing separation film which are substantially not caused by a reverse liquid crystal is produced. BRIEF DESCRIPTION OF THE DRAWINGS [Fig. 1] A cross-sectional view showing a structure in which a polarizing film is laminated on a liquid crystal element. [Fig. 2] A cross-sectional view showing the structure of a laminated polarizing film. [Fig. 3] After connecting to a linear polarized light separation film, the water mist is sprayed and then humidified. -12 - (10) 1288066 is set aside [symbol 10:12:14:18:20:22:24:26 : 28 : 30 : 32 : 34 : Figure. Ming] Liquid crystal element Adhesive layer Linear polarizing film Laminated polarizing film Linear polarizing film Linear polarizing separation film Adhesive layer Adhesive layer Release film Protective film Film feeding roller Film winding roller 36: Heavy fog spray device