TWI598157B - Polarizer waste disposal methods - Google Patents

Description

偏光板廢品處理方法Polarizer waste disposal method

本發明係有關於一種偏光板廢品處理方法，尤其是指一種有效將偏光板中的部件分離以利回收塑料或埋焚處理之偏光板廢品處理方法。 The invention relates to a method for treating a waste material of a polarizing plate, in particular to a method for treating a polarized plate waste product which is effective for separating components in a polarizing plate for recycling plastic or embedding treatment.

按，液晶顯示器被廣泛地應用於電腦、通訊、消費性電子產品等多種用途，其中偏光板為液晶顯示器之關鍵零組件，其功能主要在於主要控制特定光波的偏振方向，再加上液晶扭轉特性來達到控制光線的通過與否，形成明暗並提供必要之顯示特性，故偏光板對LCD具有相當之重要性。 According to the liquid crystal display, it is widely used in computers, communication, consumer electronics and other applications. The polarizing plate is a key component of the liquid crystal display. Its function is mainly to control the polarization direction of specific light waves, plus the liquid crystal torsional characteristics. In order to achieve control of the passage of light, to form light and dark and to provide the necessary display characteristics, the polarizing plate is of considerable importance to the LCD.

參照第1圖所示，偏光板1主要結構包含聚對苯二甲酸乙二酯(polyethylene terephthalate,PET)保護層、感壓性黏著劑(Pressure Sensitive Adhesive,PSA)、三醋酸纖維素(Tri-cellulose Acetate,TAC)支撐層、聚乙烯醇(Polyvinyl Alcohol,PVA)及離型膜所組成，其結構依序為上支撐層10(PET/TAC)、偏光層20(PVA)、下支撐層30(PET/TAC)、感壓膠40(PSA)以及離型層50(PET)所構成，而在上支撐層10通常會再覆蓋一層透明表面保護層(PET)。目前普遍的偏光板1製作方式，是將PVA薄膜先進行碘染色後再進行拉伸，使得碘分子在PVA薄膜上形成有向的排列，即可製得透過電場控制光線偏振化之作用。 Referring to Fig. 1, the main structure of the polarizing plate 1 comprises a polyethylene terephthalate (PET) protective layer, Pressure Sensitive Adhesive (PSA), and triacetate (Tri- Cellulose Acetate (TAC) consisting of a support layer, a polyvinyl alcohol (PVA) and a release film, the structure of which is the upper support layer 10 (PET/TAC), the polarizing layer 20 (PVA), and the lower support layer 30. (PET/TAC), pressure sensitive adhesive 40 (PSA), and release layer 50 (PET) are formed, and the upper support layer 10 is usually covered with a transparent surface protective layer (PET). At present, the polarizing plate 1 is generally produced by first performing iodine dyeing and then stretching, so that iodine molecules form a directed arrangement on the PVA film, and the polarized light can be controlled by the electric field.

目前廢棄的偏光板1中由於含有碘，掩埋或焚化時均有產生二次環境污染之虞，而且偏光板1中的PET及TAC等塑膠材料均有資源化再利用之潛勢，特別是TAC材質的上支撐層10、下支撐層30即占偏光板1整體成本之一半以上，因此如公告第I462786號「偏光板回收方法」即提供一種以生物鹼常溫浸泡以移除偏光板中的碘並回收塑料之方法，但該方法所消耗的反應 時間相當長，且生物鹼等有機化學原料具有易揮發的特性，在處理過程中須要不斷地監控、加藥方能維持處理效率及品質。故如何以低成本之處理方法將廢偏光板1中的碘去除，以利後續的資源化或處理/處置，乃是當前重要的研究課題。 At present, the discarded polarizing plate 1 contains iodine, which causes secondary environmental pollution during burial or incineration, and the plastic materials such as PET and TAC in the polarizing plate 1 have the potential to be reused, especially TAC. The upper support layer 10 and the lower support layer 30 of the material account for more than one-half of the overall cost of the polarizing plate 1. Therefore, as disclosed in the publication No. I462786 "Polarization method for polarizing plate", a immersion of alkaloid at room temperature to remove iodine in the polarizing plate is provided. And the method of recycling plastic, but the reaction consumed by the method The time is quite long, and the organic chemical materials such as alkaloids have volatile characteristics, and it is necessary to continuously monitor and add drugs in the process to maintain the treatment efficiency and quality. Therefore, how to remove the iodine in the waste polarizing plate 1 by a low-cost treatment method for subsequent resource utilization or treatment/disposal is an important research topic at present.

本發明之目的，在於解決上述先前技術中偏光板無法有效地處理或回收之問題。 The object of the present invention is to solve the problem that the polarizing plate cannot be effectively processed or recovered in the above prior art.

為達上述目的，本發明提供一種偏光板廢品處理方法，包含有以下步驟：步驟S1.提供偏光板廢品，並依預設尺寸將該偏光板廢品粉碎為碎片；步驟S2.運送該些碎片至一鹼洗槽，該鹼洗槽中具有含氫氧化鈉之鹼性溶液；步驟S3.浸泡該些碎片於該鹼性溶液中一段預定時間，並調節該鹼性溶液維持在預設溫度，待該等碎片中的碘分子溶於該鹼性溶液後，餘下初步處理碎片；步驟S4.傳送該些初步處理碎片及該鹼性溶液至一脫水機，利用脫水機將該些初步處理碎片及該鹼性溶液分離，並將該些初步處理碎片清洗再脫水至少一次後取得成品。 In order to achieve the above object, the present invention provides a method for processing a polarized plate waste product, comprising the steps of: step S1. providing a polarizing plate waste product, and pulverizing the polarized plate waste product into pieces according to a preset size; and step S2. transporting the pieces to the An alkali washing tank, the alkaline washing tank has an alkaline solution containing sodium hydroxide; step S3. soaking the pieces in the alkaline solution for a predetermined time, and adjusting the alkaline solution to maintain the preset temperature, After the iodine molecules in the fragments are dissolved in the alkaline solution, the preliminary processing of the fragments is carried out; step S4. transferring the preliminary treated chips and the alkaline solution to a dehydrator, and using the dehydrator to treat the preliminary processed fragments and the The alkaline solution is separated, and the preliminary treated chips are washed and dehydrated at least once to obtain a finished product.

進一步地，所述之偏光板廢品處理方法，更包含有一於步驟S1前執行之步驟S0：依偏光板廢品種類決定是否剝膜，並將偏光板廢品清洗、脫水。 Further, the method for processing the polarized plate waste product further includes a step S0 performed before the step S1: determining whether to peel the film according to the waste type of the polarizing plate, and cleaning and dehydrating the polarized plate waste product.

進一步地，該些碎片之任一邊長為2~3公分。 Further, either side of the fragments is 2 to 3 cm long.

進一步地，該鹼性溶液之氫氧化鈉濃度為1%~5%。 Further, the alkaline solution has a sodium hydroxide concentration of 1% to 5%.

進一步地，該些碎片浸泡於該鹼性溶液之該預定時間為1~6小時。 Further, the predetermined time for the fragments to be immersed in the alkaline solution is 1 to 6 hours.

進一步地，該鹼性溶液之預設溫度為40~80℃。 Further, the preset temperature of the alkaline solution is 40 to 80 °C.

進一步地，於步驟S3中該鹼性溶液與該些碎片之液固比為3至10。 Further, the liquid-solid ratio of the alkaline solution to the fragments in step S3 is 3 to 10.

是以，本發明較先前技術具有以下有益功效： Therefore, the present invention has the following beneficial effects over the prior art:

1.本發明偏光板廢品處理方法可有效地將偏光板中帶有碘分子的PVA膜與PET、TAC分離，而使PET及TAC可回收利用或是進行焚化掩埋作業，且用於鹼洗之氫氧化鈉溶液可循環至下一階段中重覆反應利用，在整體處理成本上較低廉，不似有機化學溶液易揮發而難以回收利用、且廢水處理上較為困難容易汙染環境等缺點。 1. The method for treating waste paper of the polarizing plate of the invention can effectively separate the PVA film with iodine molecules in the polarizing plate from PET and TAC, so that the PET and the TAC can be recycled or incinerated and buried, and used for caustic washing. The sodium hydroxide solution can be recycled to the next stage for repeated reaction utilization, and the overall treatment cost is relatively low, and it is not like the organic chemical solution is volatile and difficult to recycle, and the wastewater treatment is difficult and easily pollutes the environment.

1‧‧‧偏光板 1‧‧‧Polar plate

10‧‧‧上支撐層 10‧‧‧Upper support layer

20‧‧‧偏光層 20‧‧‧ polarizing layer

30‧‧‧下支撐層 30‧‧‧ lower support layer

40‧‧‧感壓膠 40‧‧‧pressure adhesive

50‧‧‧離型層 50‧‧‧ release layer

S0~S4‧‧‧步驟 S0~S4‧‧‧Steps

第1圖：為習用偏光板之平面示意圖。 Figure 1: A schematic plan view of a conventional polarizing plate.

第2圖：為本發明之方法流程圖。 Figure 2 is a flow chart of the method of the present invention.

茲就本申請案的技術特徵暨操作方式舉數個較佳實施態樣，並配合圖示說明謹述於后，俾提供審查參閱。再者，本發明中之圖式，為便於說明其比例未必按實際比例繪製，圖式中之比例並不用以限制本發明所欲請求保護之範圍。 For a more detailed description of the technical features and operation modes of the present application, and with reference to the illustrations, please refer to the review. In addition, the present invention is not intended to limit the scope of the invention as claimed.

關於本發明之技術，請參考第2圖所示，係為本發明偏光板廢品處理方法之流程圖。由於偏光板廢品的原料來源不同可能有結構上的差異，如一般廠造之偏光板不良品、瑕疵品等成品，其結構依序有TAC/PET保護層、PVA偏光層、TAC/PET保護層、PSA感壓膠、PET離型層等五個部分，但若是廢棄的偏光板半成品，則是包含了上TAC/PET膜、PVA以及下TAC/PET膜。為達到更佳的工作效率，在開始處理偏光板廢品之前可預先執行步驟S0：依偏光板廢品種類決定是否剝膜，並將偏光板廢品清洗、脫水。如前述若偏光板廢品為半成品時，可直接進行清洗與脫水，若為不良品或瑕疵品等成品時，則將PSA感壓膠撕除後再進行清洗脫水。經以上前置作業後，開始執行本發明之方法主要步驟： Regarding the technology of the present invention, please refer to FIG. 2, which is a flow chart of the method for processing the polarized plate waste of the present invention. Due to the different material sources of polarized plate waste materials, there may be structural differences, such as defective products such as polarized plates and defective products made by general factories. The structure is TAC/PET protective layer, PVA polarizing layer and TAC/PET protective layer. Five parts, such as PSA pressure sensitive adhesive and PET release layer, but if it is a semi-finished polarized plate, it contains the upper TAC/PET film, PVA and lower TAC/PET film. In order to achieve better work efficiency, step S0 can be performed in advance before starting to process the polarized plate waste product: whether the film is stripped according to the type of the polarized plate waste, and the polarized plate waste product is cleaned and dehydrated. If the polarized plate waste product is a semi-finished product as described above, it can be directly washed and dehydrated. If it is a defective product such as a defective product or a defective product, the PSA pressure sensitive adhesive is removed and then washed and dehydrated. After the above pre-operations, the main steps of the method of the present invention are started:

步驟S1：提供偏光板廢品，並依預設尺寸將該偏光板廢品粉碎為碎片。本發明中係將該偏光板廢品粉碎為任一邊邊長約2~3公分之碎片，其最長邊以不超過3公分為原則，此一規格可由粉碎機粉碎後過篩實現，以避免尺寸過厚影響後續鹼洗溶碘之效率。 Step S1: providing a polarized plate waste product, and pulverizing the polarized plate waste product into pieces according to a preset size. In the present invention, the polarized plate waste product is pulverized into pieces of any side length of about 2 to 3 cm, and the longest side thereof is not more than 3 cm. This specification can be smashed by a pulverizer and sieved to avoid oversize. The thickness affects the efficiency of subsequent alkali washing and iodine dissolution.

步驟S2：運送該些碎片至一鹼洗槽，該鹼洗槽中具有含氫氧化鈉之鹼性溶液。於本步驟中，可於該鹼洗槽中預先置放固態之苛性鈉，並注入溫水攪拌使鹼洗槽內溶液呈現鹼性。 Step S2: transporting the pieces to an alkali washing tank having an alkaline solution containing sodium hydroxide. In this step, solid caustic soda may be preliminarily placed in the alkali washing tank, and stirred in warm water to make the solution in the alkali washing tank alkaline.

步驟S3：浸泡該些碎片於該鹼性溶液中一段預定時間，並調節該鹼性溶液維持在預設溫度，待該等碎片中的碘分子溶於該鹼性溶液後，餘下初步處理碎片。於本步驟中，該鹼性溶液之氫氧化鈉濃度較佳為1%~5%，液固比則在3至10之間，該預定時間為1~6小時，而該預設溫度為40~80℃之範圍。實驗中，提高反應溫度有助於溶出碘分子，但由於PVA為聚醋酸乙烯酯經部分或全部水解後得到的水溶性高分子聚合物，其性能介於塑膠與橡膠之間，玻璃轉移溫度約為60~85℃，當溫度較高時，在浸漬溶洗液中的半成品廢偏光板樣品將變得黏稠，造成浸漬溶洗液的黏度增加而影響攪拌效果，因此建議反應溫度較適當為50~70℃之範圍，特別在於55℃以下時PVA不會呈現黏結成團之特性，較易進行攪拌等作業。於一實施態樣中，可提供氣罩收集反應期間所產生之蒸汽，捕集蒸汽並冷卻後導回該鹼洗槽中循環使用。 Step S3: soaking the pieces in the alkaline solution for a predetermined time, and adjusting the alkaline solution to maintain a preset temperature, and after the iodine molecules in the pieces are dissolved in the alkaline solution, the preliminary processing of the pieces is left. In this step, the sodium hydroxide concentration of the alkaline solution is preferably 1% to 5%, and the liquid-solid ratio is between 3 and 10, and the predetermined time is 1 to 6 hours, and the preset temperature is 40. ~80 °C range. In the experiment, increasing the reaction temperature helps to dissolve the iodine molecules, but since PVA is a water-soluble polymer obtained by partially or completely hydrolyzing polyvinyl acetate, its performance is between plastic and rubber, and the glass transition temperature is about For 60~85 °C, when the temperature is high, the semi-finished waste polarizer sample in the impregnation solution will become thicker, which will increase the viscosity of the impregnation solution and affect the stirring effect. Therefore, it is recommended that the reaction temperature be 50. In the range of ~70 ° C, especially when it is below 55 ° C, PVA does not exhibit the characteristics of sticking into agglomerate, and it is easier to perform stirring and the like. In one embodiment, steam generated during the hood collection reaction can be provided, trapped and cooled, and then returned to the caustic tank for recycling.

步驟S4：傳送該些初步處理碎片及該鹼性溶液至一脫水機，利用脫水機將該些初步處理碎片及該鹼性溶液分離，並將該些初步處理碎片清洗再脫水至少一次後取得成品。於本實施態樣中，分離出的該鹼性溶液可回收至下一次鹼洗作業中再次利用，或是排入廢水處理設備中進行過濾、化學混凝、浮除、中和、離子交換及活性碳吸附作業，在此不予限制。取得之成品 即為PET或TAC塑膠碎片，可直接進行焚化或掩埋而不產生環境汙染，亦可將其融煉回收作為其他塑料成品。 Step S4: transferring the preliminary treatment fragments and the alkaline solution to a dehydrator, separating the preliminary treatment fragments and the alkaline solution by using a dehydrator, and washing the preliminary treatment fragments and dehydrating at least once to obtain the finished product. . In this embodiment, the separated alkaline solution can be recycled to the next alkali washing operation for reuse, or discharged into a wastewater treatment facility for filtration, chemical coagulation, flotation, neutralization, ion exchange, and The activated carbon adsorption operation is not limited herein. Finished product It is a piece of PET or TAC plastic that can be directly incinerated or buried without causing environmental pollution. It can also be melted and recycled as other finished plastic products.

為進一步說明本案之功效，請參照以下具體例，並針對半成品廢偏光板進行浸漬溶洗除碘溶出進行探討。 In order to further illustrate the efficacy of this case, please refer to the following specific examples, and discuss the immersion washing and iodine dissolution of the semi-finished waste polarizing plate.

《具體例》 Specific case

取400g洗淨之半成品廢偏光板並粉碎成碎片，再置入1600g濃度為4%之氫氧化鈉溶液中，隔水加熱至溫度50℃並維持120分鐘後，測得發現半成品廢偏光板碎片浸漬溶液中碘的濃度為4864mg/l，由肉眼觀之，能查覺成品之顏色由原本半成品廢偏光板碎片的藍黑色轉為透明或淡棕色，由透過拉曼光譜儀分析之，亦能觀察到拉曼數約108及160cm^-1的頻譜上PVA中碘之特徵峰消失，因此本案之方法確實能達到去除偏光板中碘分子之效果。 Take 400g of the washed semi-finished waste polarizing plate and pulverize it into pieces, then put it into 1600g of 4% sodium hydroxide solution, heat it to 50 ° C and maintain it for 120 minutes, then find the semi-finished waste polarizer fragments. The concentration of iodine in the impregnation solution is 4864mg/l. From the naked eye, it can be seen that the color of the finished product is changed from blue black of the original semi-finished waste polarizing plate to transparent or light brown. It can also be observed by Raman spectroscopy. The characteristic peak of iodine in PVA disappears in the spectrum of Raman number of about 108 and 160 cm ^-1 , so the method of the present invention can achieve the effect of removing iodine molecules in the polarizing plate.

綜上所述，本發明利用氫氧化鈉溶液浸洗廢偏光板，可將偏光板廢品中用以染色PVA薄膜的碘分子完善地去除，處理後之PET/TAC碎片掩埋或焚化時均不會產生二次環境污染之虞，而所得之成品亦可作為紡織業或塑膠製造業之回收塑料使用。 In summary, the present invention utilizes a sodium hydroxide solution to immerse the waste polarizing plate, and the iodine molecules used for dyeing the PVA film in the polarized plate waste product can be perfectly removed, and the treated PET/TAC fragments are not buried or incinerated. After the secondary environmental pollution, the finished product can also be used as recycled plastic in the textile or plastics manufacturing industry.

S0~S4‧‧‧步驟 S0~S4‧‧‧Steps

Claims (2)

一種偏光板廢品處理方法，包含有以下步驟：步驟S1.提供偏光板廢品，並依預設尺寸將該偏光板廢品粉碎為碎片；步驟S2.運送該些碎片至一鹼洗槽，該鹼洗槽中具有含氫氧化鈉之鹼性溶液；步驟S3.浸泡該些碎片於該鹼性溶液中一段預定時間，並調節該鹼性溶液維持在預設溫度，待該等碎片中的碘分子溶於該鹼性溶液後，餘下初步處理碎片；以及步驟S4.傳送該些初步處理碎片及該鹼性溶液至一脫水機，利用脫水機將該些初步處理碎片及該鹼性溶液分離，並將該些初步處理碎片清洗再脫水至少一次後取得成品；其中該些碎片之任一邊長為2~3公分，該鹼性溶液之氫氧化鈉濃度為1%~5%，該些碎片浸泡於該鹼性溶液之該預定時間為1~6小時，該鹼性溶液之預設溫度為40~80℃，且於步驟S3中該鹼性溶液與該些碎片之液固比為3至10。 A method for treating a waste material of a polarizing plate comprises the following steps: Step S1. Providing a waste material of a polarizing plate, and pulverizing the waste material of the polarizing plate into pieces according to a preset size; Step S2: transporting the pieces to an alkali washing tank, the alkali washing The tank has an alkaline solution containing sodium hydroxide; step S3. soaking the fragments in the alkaline solution for a predetermined time, and adjusting the alkaline solution to maintain a preset temperature, and the iodine molecules in the fragments are dissolved. After the alkaline solution, the preliminary treatment of the fragments is left; and step S4. transferring the preliminary treated chips and the alkaline solution to a dehydrator, separating the preliminary treated chips and the alkaline solution by using a dehydrator, and The preliminary treatment of the debris is washed and then dehydrated at least once to obtain a finished product; wherein the sides of the fragments are 2 to 3 cm long, and the alkaline solution has a sodium hydroxide concentration of 1% to 5%, and the fragments are soaked in the The predetermined time of the alkaline solution is 1 to 6 hours, the preset temperature of the alkaline solution is 40 to 80 ° C, and the liquid-solid ratio of the alkaline solution to the fragments in step S3 is 3 to 10. 如申請專利範圍第1項所述之偏光板廢品處理方法，更包含有一於步驟S1前執行之步驟S0：依偏光板廢品種類決定是否剝膜，並將偏光板廢品清洗、脫水。 The method for processing a polarized plate waste product according to claim 1 further includes a step S0 performed before the step S1: determining whether to strip the film according to the waste type of the polarizing plate, and cleaning and dehydrating the polarized plate waste product.