TWI588184B - Recycling method for discard optical film and recycling equipment thereof - Google Patents

Description

Waste optical film recycling method and recycling device thereof

The present invention relates to an optical film recycling method and a recycling apparatus thereof, and more particularly to a recycling optical film recycling method and a recycling apparatus therefor.

Conventional optical films are often incinerated or buried after they have been tested for poor quality. However, such a treatment method not only causes harm and burden to the environment, but also wastes materials for discarding the optical film. Therefore, there is an urgent need to propose a new technology to recover waste optical films.

The present invention provides a recycling method for a waste optical film and a recycling device thereof, which can improve the above-mentioned conventional problems.

According to another embodiment of the present invention, a method of recovering an optical film is proposed. The recycling method includes the following steps. Providing a waste optical film comprising: a first polymer and a second polymer; dissolving the first polymer using a first solvent to form a first polymer solution, wherein the first solvent does not dissolve the second a polymer; mixing the first polymer solution with a second solvent to precipitate the first polymer, The first polymer, the first solvent and the second solvent are mixed, wherein the first solvent and the second solvent constitute a mixed solution; and the precipitated first polymer is dried.

According to another embodiment of the present invention, a recycling apparatus for a film is proposed. The recycling device includes a first processing tank, a second processing tank, and a dryer. The first processing tank is configured to dissolve a first polymer of a waste optical film with a first solvent to form a first polymer solution, wherein the first solvent does not dissolve a second polymer of the waste optical film. The second treatment tank is configured to mix the first polymer solution and a second solvent to precipitate the first polymer, wherein the first polymer, the first solvent and the second solvent are mixed, and the first solvent and the second solvent are combined mixture. A dryer is used to dry the precipitated first polymer.

In order to better understand the above and other aspects of the present invention, the preferred embodiments are described below, and in conjunction with the drawings, the detailed description is as follows:

10‧‧‧Waste optical film

10’‧‧‧Second waste

11‧‧‧Four polymer layer

12‧‧‧ first layer

13‧‧‧First polymer layer

14‧‧‧Secondary layer

15‧‧‧Surface treatment layer

16‧‧‧Second polymer layer

100‧‧‧Recycling equipment

101‧‧‧First screen

102‧‧‧ third treatment tank

103‧‧‧Second filter

104‧‧‧First valve

106‧‧‧First filter

108‧‧‧First pump

109‧‧‧crushing mechanism

110‧‧‧Second valve

111‧‧‧cooler

112‧‧‧Evaporator

114‧‧‧First treatment tank

115‧‧‧Adjustment slot

116‧‧‧third valve

118‧‧‧Second filter

120‧‧‧Second pump

122‧‧‧fourth valve

124‧‧‧Second treatment tank

126‧‧‧ fifth valve

128‧‧‧ third filter

130‧‧‧The third pump

132‧‧‧ sixth valve

134‧‧‧Distillation tower

136‧‧‧Condenser

138‧‧‧ reboiler

140‧‧‧Solvent tank

142‧‧‧ seventh valve

144‧‧‧fourth pump

146‧‧‧fourth filter

148‧‧‧The eighth valve

150‧‧‧Regulator tank

152‧‧‧Ninth valve

154‧‧‧The fifth pump

156‧‧‧ tenth valve

158‧‧‧Eleventh valve

160‧‧‧Dryer

P1’‧‧‧polymeric jelly

P2‧‧‧ first polymer

P3’‧‧‧ Third Waste

P4‧‧‧ third polymer

S1‧‧‧ third solvent

S2‧‧‧Iodine solution

S2’‧‧‧Iodine-containing gel

S3‧‧‧ first solvent

S4‧‧‧First polymer solution

S5‧‧‧Second solvent

S6‧‧‧ mixed solution

S7, S10‧‧‧ pH adjuster

S8‧‧‧ Acid

S9‧‧‧Second polymer solution

S102, S104, S106, S108, S109, S110, S202, S204, S206, S208, S210, S212, S214, S216, S218, S220, S222, S224, S226, S302, S304, S306, S308‧‧

FIG. 1 is a flow chart showing the recovery of iodine adsorbed by an optical film according to an embodiment of the present invention.

2 is a cross-sectional view showing a waste optical film according to an embodiment of the present invention.

FIG. 3 is a partial schematic view of a recycling apparatus according to an embodiment of the present invention.

4 is a schematic view of a recycling apparatus according to another embodiment of the present invention.

FIG. 5 is a flow chart showing the recovery of the first polymer and the second polymer of the optical film according to another embodiment of the present invention.

FIG. 6 is a schematic view showing a recycling apparatus according to another embodiment of the present invention.

Figure 7 is a flow chart showing the reaction of the first polymer into a third polymer in accordance with another embodiment of the present invention.

The optical film comprises a plurality of polymer layers, and the materials of the polymer layers can be recovered in the embodiment of the invention to achieve environmental protection and cost reduction effects of waste recycling.

Referring to FIG. 1 , a flow chart for recovering iodine adsorbed by the waste optical film 10 according to an embodiment of the present invention is shown.

In step S102, the waste optical film 10 as shown in Fig. 2 is provided. 2 is a cross-sectional view of the waste optical film 10 in accordance with an embodiment of the present invention. The waste optical film 10 of the present embodiment is described by taking a polarizing film as an example, but is not limited thereto.

The waste optical film 10 (first waste) includes a fourth polymer layer 11, two first adhesive layers 12, two first polymer layers 13, two second adhesive layers 14, a surface treatment layer 15, and two second polymerizations. a layer 16, wherein the first polymer layer 13 passes through the first adhesive layer 12 and then the fourth polymer layer 11, and the surface treatment layer 15 is formed on one of the first polymer layers 13 and through the second adhesive layer 14 One of the second polymer layers 16 passes through the other second polymer layer 16 and the other second polymer layer 13 follows the other first polymer layer 13.

In terms of material, in one embodiment, the fourth polymer layer 11 includes a fourth polymer that adsorbs iodine. In one embodiment, the fourth polymer layer 11 may be formed by adsorbing a dichroic dye of a polyvinyl alcohol (PVA) film; for example, an iodine-based polarizer having iodine as a dichroic dye. The formation of the polarizer usually has the following steps: a swelling treatment, a dyeing treatment, a stretching treatment, a crosslinking treatment, a washing treatment, and a drying treatment. Among them, the stretching treatment causes the polyvinyl alcohol to have a polarizing effect.

The first adhesive layer 12 may be a transparent adhesive layer made of an aqueous adhesive, wherein the material of the transparent adhesive comprises polyvinyl alcohol powder. Alternatively, the first adhesive layer 12 may also be a UV curable adhesive such as an ultraviolet curable resin.

The first polymer layer 13 comprises a first polymer, such as, for example, Triacetate Cellulose (TAC) or Polymethylmethacrylate (PMMA). The second adhesive layer 14 is formed, for example, of acrylic rubber, silicone rubber, ultraviolet curable adhesive (for example, ultraviolet curable resin) or thermosetting adhesive (for example, thermosetting resin). In some embodiments, the second adhesive layer 14 is a Pressure Sensitive Adhesive (PSA) formed of acrylic resin.

The surface treatment layer 15 is a treatment layer of the first polymer layer 13, and is, for example, an antifouling layer that prevents surface contamination, an antistatic layer that prevents an electrostatic effect from occurring on the surface, a hard coat layer that prevents scratches, and the like. The above antistatic layer is, for example, (a) various cationic antistatic agents having a cationic group such as a quaternary ammonium salt, a pyridinium group, a primary amino group, a secondary amino group or a tertiary amino group; (b) having a sulfonic acid base and a sulfate base An anionic antistatic agent such as an anion group such as a phosphate base or a phosphonic acid base; (c) an amphoteric antistatic agent such as an amino acid or an aminosulfate; (d) an amino alcohol, a glycerin or a polyethylene a nonionic antistatic agent such as an alcohol; (e) a polymer type antistatic agent obtained by polymerizing the antistatic agent as described above. In another embodiment, the surface may also be modified on the surface of the first polymer layer 13 by a corona discharge technique to increase the second adhesive layer 14 Adhesion to the first polymer layer 13. Alternatively, an easy subsequent chemical treatment can be performed on the first polymer layer 13, so that the second adhesive layer 14 is easily adhered to the first polymer layer 13, and the amount of residual glue can be reduced or even avoided.

Further, the second polymer layer 16 is, for example, a release film or a protective film including a second polymer such as polyethylene terephthalate (PET).

In step S104, the waste optical film 10 can be crushed using the crushing mechanism 109, and the large waste optical film 10 can be made into a plurality of small waste optical films 10. The side length of either side of the broken waste optical film 10 may be not more than 15 cm, or the area of the discarded waste optical film 10 may be not more than 225 cm 2 to improve the recovery efficiency. In another embodiment, even if the waste optical film 10 is not broken, or the side length of either side of the broken waste optical film 10 is substantially equal to or greater than 15 cm, or the area is substantially equal to or greater than 225 cm 2 , The recycling purpose of the embodiment of the present invention is not affected.

In step S106, the iodine adsorbed by the fourth polymer is dissolved in a third solvent. This step can be accomplished by the recycling apparatus 100 as shown in FIG. FIG. 3 is a partial schematic view of a recycling apparatus 100 in accordance with an embodiment of the present invention.

The optical film recovery apparatus 100 includes a first screen 101, a third processing tank 102, a second screen 103, a first valve 104, a first filter 106, a first pump 108, a second valve 110, and an evaporator 112. In this step, the waste optical film 10 can be placed in the third treatment tank 102, and the iodine adsorbed by the fourth polymer is dissolved using the third solvent S1 to form the iodine solution S2. The third solvent S1 is, for example, hot water, glacial acetic acid, A potassium hydroxide solution or other liquid that allows iodine to be dissolved therein, wherein the temperature of the hot water may range from about 80 to about 100 degrees Celsius.

In one embodiment, the weight of the first solvent S1 may be 10 times or more the weight of the thermal waste optical film 10, and the waste optical film 10 and the first solvent S1 are heated to about 80 degrees Celsius, and/or about The waste optical film 10 and the first solvent S1 are stirred at a rate of between 5 rpm (revolutions per minute) to about 60 rpm for about 30 minutes or more to ensure that all or almost all of the iodine of the thermal waste optical film 10 is dissolved in the third solvent S1. in. As used herein, "almost all" refers to a ratio of at least 50%, such as between about 90% and about 99%.

The fourth polymer and the first adhesive layer 12 (which is similar in material to the fourth polymer) are capable of absorbing the third solvent S1 and forming a polymeric gel P1'. The polymerized gum P1' is converted into a softness, so that the upper layer structure and the lower layer structure of the fourth polymer layer 11 of the waste optical film 10 can be easily separated to become the second waste 10'. Since the third solvent S1 does not dissolve the second polymerization layer 13, the second adhesive layer 14, the surface treatment layer 15, and the third polymerization layer 16, the second polymerization layer 13, the second adhesive layer 14, the surface treatment layer 15, and the third The polymeric layer 16 remains solid. In summary, the waste optical film 10 becomes an iodine solution S2, a polymeric jelly P1', and a second waste 10' under the action of the third solvent S1, wherein the polymeric jelly P1' and the iodine solution S2 are in this step. Mix together to form an iodine-containing gum S2'.

In step S108, after the iodine adsorbed by the fourth polymer is completely or almost completely dissolved in the third solvent S1, the second waste 10' and the iodine-containing gum S2' can be separated. The polymeric gum P1' of the iodine-containing gum S2' and the iodine solution S2 can be followed The steps are separated by a first filter 106.

First, the separation of the second waste 10' and the iodine-containing gel S2' is exemplified, and the second waste can be separated by using the first filter 101 disposed in the third treatment tank 102 by forced pumping. 10' with iodine-containing gum S2'. Since the inner diameter of the mesh of the first filter 101 is smaller than either side of the waste optical film 10, the second waste 10' can be blocked by the first filter 101 and cannot enter the first filter 106. The iodine-containing gum S2' can then enter the first filter 106 through the mesh of the first screen 101. Additionally, the suction of the forced pumping may be provided by the first pump 108 or another pump. In another embodiment, the first filter 101 may also be disposed outside the third processing tank 102, such as between the third processing tank 102 and the first valve 104, or disposed in the first valve 104 and the first filter. Between the devices 106.

In step S109, after the iodine-containing gel S2' enters the first filter 106, the second filter 103 disposed in the first filter 106 can adsorb the polymer gel P1' to form a polymer gel. P1' does not pass through the second screen 103, but the liquid iodine solution S2 can pass through the second screen 103, so that the polymerized gel P1' and the iodine solution S2 can be separated. In one embodiment, the mesh of the second screen 103 can be substantially equal to or less than 5 microns, but can also be greater than 5 microns, such as 10 microns.

In step S110, after the iodine solution S2 passes completely or almost completely through the second filter 103, the second valve 110 can be opened to allow the iodine solution S2 to enter the evaporator 112 to increase the iodine concentration of the iodine solution S2 to a predetermined concentration. . This preset concentration is, for example, 10%, but may be lower or higher than 10%. Since the iodine concentration is increased to a preset concentration, the recovery efficiency of iodine can be improved. So far, the iodine in the waste optical film 10 is completed. Recycling.

Further, in an embodiment, the iodine solution S2 may be cooled using the cooler 111 and/or the pH value of the iodine solution S2 may be adjusted in the adjustment tank 115 before the iodine solution S2 enters the evaporator 112. For example, the temperature of the iodine solution S2 is cooled to about 65 degrees Celsius and/or the pH of the iodine solution S2 is adjusted to be between 10 and 11. Thus, the recovery efficiency of the iodine solution S2 can be improved.

As shown in the enlarged view of Fig. 3, since the polymerized gel P1' is adsorbed by the second screen 103, it does not pass through the second screen 103. Next, the polymeric gum P1' may be taken out from the first filter 106, and then the polymeric gel P1' may be dried using a dryer 160 as shown in Fig. 4 to obtain a dried fourth polymer. At this point, the recovery of the fourth polymer is completed. In another embodiment, the polymeric gum P1' can be dried directly within the first filter 106. Since the recovered fourth polymer is water-absorptive, it can be used as a moisture-proofing agent, a desiccant or a culture soil.

As can be seen from the above, since the second waste 10' already contains no iodine, it can be directly incinerated, but the material of the second waste 10' can be recovered. The following is an example.

4 and 5, FIG. 4 is a schematic diagram of a recycling apparatus 100 according to another embodiment of the present invention, and FIG. 5 is a first polymer of the optical film 10 according to another embodiment of the present invention. A recovery scheme for the second polymer.

As shown in FIG. 4, the recycling apparatus 100 further includes a first processing tank 114, a third valve 116, a second filter 118, a second pump 120, a fourth valve 122, a second processing tank 124, and a fifth valve 126. a third filter 128, a third pump 130, a sixth valve 132, a distillation column 134, a condenser 136, a reboiler 138, a solvent tank 140, The seventh valve 142, the fourth pump 144, the fourth filter 146, the eighth valve 148, the regulator tank 150, the ninth valve 152, the fifth pump 154, the tenth valve 156, and the eleventh valve 158.

In step S202, a waste optical film is provided, which may be the aforementioned second waste 10' or other optical film comprising the first polymer and the second polymer, for example, a raw material comprising the first polymer or the second polymer Membrane.

In step S204, the first polymer is dissolved with the first solvent S3 to form a first polymer solution S4. For example, the second waste 10' may be placed in the first processing tank 114, wherein the first solvent S3 may be pre-stored with the first solvent S3, and the first solvent S3 may dissolve the first polymer layer 13 One polymer, but does not dissolve the second polymer. During the dissolution process, the second waste 10' may be heated to the first solvent S3 to about 80 degrees Celsius and the second waste 10' and the first solvent S3 may be stirred at a rate between about 10 rpm and about 60 rpm. It lasted for 45 minutes to ensure that the first polymer in the first waste 10' was almost or completely dissolved in the first solvent S3. In an embodiment, the first solvent S3 is, for example, glacial acetic acid. Further, the ratio of the second waste 10' to the first solvent S3 is about 1:30, but may be other ratio values.

After the first solvent S3 dissolves the first polymer, the first polymer solution S4 is formed. Since the first solvent S3 does not dissolve the second polymer and the second adhesive layer 14, the second polymer and the second adhesive layer 14 become the third waste P3'. In summary, in step S204, the second waste 10' becomes the first polymer solution S4 and the third waste P3' by the action of the first solvent S3.

After the first polymer in the second waste 10' is dissolved or dissolved completely in the first solvent S3, the third valve 116 and the fourth valve 122 may be opened, and driven by the second pump 120, The first polymer solution S4 in the treatment tank 114 flows into the second treatment tank 124 through the third valve 116 and the fourth valve 122.

In step S206, after the first polymer solution S4 is almost or completely discharged out of the first treatment tank 114, the third waste P3' is taken out from the first treatment tank 114. Then, in step S208, nano-grade inorganic particles, organic acrylic particles, antistatic agents or anti-electromagnetic agents may be added to the third waste P3' to reduce the viscosity of the third waste P3'. Sex. Prior to this, the third waste P3' can be ground into a powder using a grinder. Then, in step S210, the third waste P3' is dried to complete the recovery of the second polymer. In application, the second polymer P3' can be reshaped into a transparent package after being melted at 260 degrees Celsius, and can be used as an optical film product package.

Next, the treatment of the first polymer solution S4 will be explained.

As shown in FIG. 4, the first polymer solution S4 flowing out of the first treatment tank 114 can enter the second filter 118 through the third valve 116. The second filter 118 can filter the solid matter remaining in the first polymer solution S4 to increase the purity of the first polymer solution S4.

In step S212, the first polymer solution S4 and the second solvent S5 are mixed to precipitate the first polymer. For example, the second solvent S5 may be preliminarily stored in the second treatment tank 124, and the first polymer solution S4 and the second solvent S5 may be mixed to precipitate a solid first polymer, which is in the form of particles or spheres. Controlled by the fourth valve 122 The flow rate of the first polymer solution S4 is made such that the first polymer solution S4 is titrated into the second treatment tank 124 and mixed with the second solvent S5. Since the titration method is employed, the purity of the precipitated first polymer is high (if the titration method is not used, the precipitated first polymer may contain a glacial acetic acid solution) and/or the particles are small. In one embodiment, the precipitated first polymer may have an outer diameter of between about 50 microns and about 3 mm. The first polymer having a small particle size facilitates subsequent drying treatment, for example, the time required to dry the first polymer is shortened (increased efficiency). After the first polymer is precipitated, the second treatment tank 124 simultaneously contains the precipitated first polymer, the first solvent S3 and the second solvent S5 are mixed together, wherein the first solvent S3 and the second solvent S5 form a mixed solution. S6 (The mixed solution S can be separated into the first solvent S3 and the second solvent S5 through the subsequent steps S216 to S220, which will be described later). Further, the second solvent S5 is, for example, water, glacial acetic acid, alcohols, ketones, esters or other liquids which are only dissolved with glacial acetic acid but are not dissolved with the first polymer, wherein the alcohol is, for example, methanol.

In step S214, after the first polymer in the first polymer solution S4 is completely or almost completely precipitated, the precipitated first polymer and the mixed solution S6 may be separated. For example, the fifth valve 126 and the sixth valve 132 may be opened, and the mixed solution S6 is discharged from the second processing tank 124 under the driving of the third pump 130. The discharged mixed solution S6 may first pass through the third filter 128 to filter out the solid matter remaining in the mixed solution S6, thereby increasing the purity of the mixed solution S6.

In step S216, the mixed solution S6 is driven into the distillation column 134 under the driving of the third pump 130 to separate the first solvent S3 from the second solvent S5. The first solvent S3 can be separated by the difference in boiling points of the first solvent S3 and the second solvent S5. With the second solvent S5. For example, the boiling point of the second solvent S5 is lower than the first solvent S3. In step S218, the reboiler 138 is controlled to adjust the temperature of the distillation column 134 to evaporate the second solvent S5 having a lower boiling point into a vapor state. The second solvent S5 in a vapor state is condensed into a liquid through the condenser 136 and then recovered into the solvent tank 140. The second solvent S5 stored in the solvent tank 140 can be recycled and reused.

In step S220, after the second solvent S5 is evaporated almost completely or completely from the mixed solution S6, the first solvent S3 having a higher boiling point remains. The first solvent S3 can be recovered into the first treatment tank 114 to achieve the effect of recycling.

As shown in Fig. 4, after the mixed solution S6 in the second treatment tank 124 is discharged almost or completely from the second treatment tank 124, the fifth valve 126 can be closed to facilitate the treatment of the precipitated first polymer.

For example, in step S222, the ninth valve 152 and the tenth valve 156 can be opened, and under the driving of the fifth pump 154, the pH adjusting agent S7 is allowed to enter the second processing tank 124 to mix the acid and alkali. The value adjuster S7 and the precipitated first polymer neutralize the first polymer by acid and base. For example, when the acidity of the precipitated first polymer is too high, the pH adjuster S7 may be an alkali solution such as potassium hydroxide to lower the acidity of the precipitated first polymer.

In step S224, after the acid-base neutralization of the precipitated first polymer is completed, the tenth valve 156 may be closed to stop the acid-base neutralization of the first polymer, and the seventh valve 142 and the eighth valve are turned on. Valve 148. And driven by the fourth pump 144, the pH adjusting agent S7 in the second processing tank 124 flows through the fourth filter 146 through the seventh valve 142. The fourth filter 146 can filter out the residual in the acid-base adjusting agent S7 The solid matter is left to increase the purity of the pH adjuster S7. Driven by the fourth pump 144, the filtered pH adjuster S7 flows into the conditioner tank 150 through the eighth valve 148 for recycling.

If it is necessary to use the pH adjusting agent S7 stored in the adjusting agent tank 150, the ninth valve 152 and the tenth valve 156 can be opened and stored in the adjusting agent tank 150 under the driving of the fifth pump 154. The pH adjuster S7 is supplied to the second treatment tank 124 through the ninth valve 152 and the tenth valve 156. Further, the eleventh valve 158 may be selectively opened or closed to adjust the mixing ratio of the pH adjuster S7 and the second solvent S5 stored in the solvent tank 140.

In step S226, after the acid-base adjusting agent S7 in the second processing tank 124 is recovered into the adjusting agent tank 150 almost or completely from the second processing tank 124, the precipitated portion can be taken out from the second processing tank 124. A polymer P2 is then dried using a dryer 160 to complete the recovery of the first polymer P2. In one embodiment, the drying conditions are, for example, from 60 degrees Celsius to 90 degrees Celsius for about 24 hours. In another embodiment, the precipitated first polymer may be retained in the second treatment tank 124 and heated directly in the second treatment tank 124 to dry the precipitated first polymer to complete the first polymerization. Recycling of things.

In the application, the first polymer is cellulose triacetate, and the solvent which can completely dissolve the cellulose triacetate such as dichloromethane or chloroform can be mixed and dissolved, and then added with additives such as ultraviolet absorbers and plasticizers, and then cast. After drying the film into a film of cellulose triacetate, or using high-temperature hot-melt cellulose acetate to inject various shapes of molds, such as cellulose acetate frames, automobile steering wheel, Filter the heart and so on.

Please refer to FIGS. 6 and 7 . FIG. 6 is a schematic diagram of a recycling apparatus 100 according to another embodiment of the present invention, and FIG. 7 illustrates a reaction of the first polymer P2 into a third embodiment according to another embodiment of the present invention. Flowchart of polymer P4.

As shown in FIG. 6, the recycling device 100 includes a first processing tank 114, a third valve 116, a second filter 118, a second pump 120, a fourth valve 122, a second processing tank 124, and a fifth valve 126. The third filter 128, the third pump 130, the sixth valve 132, the distillation column 134, the condenser 136, the reboiler 138, the solvent tank 140, the eleventh valve 158, and the dryer 160.

In step S302, the first polymer P2 and the first solvent S3 may be mixed to form a first polymer solution S4. For example, the first solvent S3 may be pre-stored in the first treatment tank 114, and the first polymer and the first solvent S3 may be mixed in the first treatment tank 114 after the first polymer is added. The first solvent S3 dissolves the first polymer to form the first polymer solution S4. During the dissolution process, the first polymer and the first solvent S3 may be heated to 80 degrees Celsius and the first polymer and the first solvent S3 may be stirred for 45 minutes to ensure that the first polymer is dissolved almost or completely in the first solvent S3. in. In an embodiment, the first solvent S3 is, for example, glacial acetic acid. Further, the ratio of the first polymer P2 to the first solvent S3 is about 1:30, but may be other ratios. In addition, the first processing tank 114 of this step may omit the first screen 101. The first polymer P2 of this step may be the dried first polymer of step S226 of Fig. 5, but may be the first polymer obtained in other forms.

In step S304, the first polymer P2 is dissolved almost or completely After the first polymer solution S4 is formed in the first solvent S3, the first polymer solution S4 and the acid solution S8 are mixed to form a second polymer solution S9. For example, the acid solution S8 is externally added to the first treatment tank 114 without taking out the first polymer solution S4 in the first treatment tank 114 to mix the first polymer solution S4 and the acid solution S8. After the first polymer solution S4 is mixed with the acid solution S8, the first polymer P2 therein may be esterified or hydrolyzed into the third polymer P4. In one embodiment, if the first polymer P2 is cellulose triacetate, the third polymer P4 may be cellulose diacetate (DAC), and the acid solution S8 used may be sulfuric acid. The chemical structure before and after the reaction is as follows.

In the esterification or hydrolysis process, the first polymer solution S4 and the acid solution S8 may be heated to between about 70 degrees Celsius and 90 degrees Celsius, and the first polymer solution S4 and the acid solution S8 may be stirred for 1 hour or more. It is ensured that the first polymer P2 in the first polymer solution S4 is almost or completely esterified or hydrolyzed into the third polymer P4.

In step S306, after the first polymer P2 is almost or completely esterified or hydrolyzed into the third polymer P4, the second polymer solution S9 and the pH adjuster S10 are mixed in the first treatment tank 114, Neutralizing the second polymer with acid and alkali Liquid S9. In an embodiment, the pH adjuster S10 may be sodium acetate.

After the acid and alkali are neutralized, the third valve 116 and the fourth valve 122 are opened, and under the driving of the second pump 120, the second polymer solution S9 flows into the second through the third valve 116 and the fourth valve 122. Processing tank 124. Before the second polymer solution S9 flows into the second treatment tank 124, it passes through the second filter 118 to filter the residual solid matter to increase the purity of the second polymer solution S9.

In step S308, the second polymer solution S9 and the second solvent S5 are mixed to precipitate a solid third polymer P4. For example, the second solvent S5 may be preliminarily stored in the second treatment tank 124, and the second polymer solution S9 may be mixed with the second solvent S5 to precipitate a third polymer P4 which is solid. The fourth valve 122 controls the flow rate of the second polymer solution S9 to allow the second polymer solution S9 to enter the second treatment tank 124 in a titrated manner. Since the titration method is employed, the purity of the precipitated third polymer P4 is high (if the titration method is not used, the precipitated third polymer P4 may contain a glacial acetic acid solution) and/or the particles are small. The third polymer P4 having a small particle size facilitates the subsequent drying treatment, for example, the time required to dry the third polymer P4 is shortened. After the third polymer P4 is precipitated, the second treatment tank 124 contains the precipitated third polymer P4, the first solvent S3 and the second solvent S5 are mixed together, wherein the first solvent S3 forms a mixture with the second solvent S5. Solution S6. The first solvent S3 and the second solvent S5 can be separated and recovered by the steps S216 to S220, and will not be described again.

In step S310, after the solution S6 to be mixed is almost or completely discharged from the second treatment tank 124, the third polymerization precipitated from the second treatment tank 124 is taken out. The substance P4 is then dried through a dryer 160. The drying conditions may be similar to the above first polymer P2, and will not be described herein.

In summary, the recycling apparatus and the recycling method thereof according to the embodiments of the present invention can recover the materials of the plurality of layer structures of the waste optical film, and the solvent used in the recycling process can also be recycled and reused to achieve environmental protection purposes. In one embodiment, the optical film is typically a composite of 5 to 14 layers of material and uses an aqueous polyvinyl alcohol adhesive, an acrylic adhesive, or various bridging forms of the adhesive, the composite of which covers Chemical and physical combination, such as hydrogen bonding, van der Waals force, wettability, adhesion, etc. Through the recycling method of the embodiment of the present invention, various bridging forms can be destroyed to recover the materials of the layer structures.

In conclusion, the present invention has been disclosed in the above preferred embodiments, and is not intended to limit the present invention. A person skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, the scope of the invention is defined by the scope of the appended claims.

S202, S204, S206, S208, S210, S212, S214, S216, S218, S220, S222, S224, S226‧‧ steps

Claims (14)

A method for recovering an optical film, comprising: providing a waste optical film comprising a first polymer and a second polymer; dissolving the first polymer using a first solvent to form a first polymerization a solution in which the first solvent does not dissolve the second polymer; mixing the first polymer solution with a second solvent to precipitate the first polymer, wherein the first polymer, the first solvent and the solution a second solvent mixture, wherein the first solvent and the second solvent form a mixed solution; and the precipitated first polymer, wherein after the first polymer is dissolved in the first solvent, the recovery method is further The method comprises: reducing viscosity of the second polymer by adding inorganic particles of nanometer grade, organic acrylic particles, antistatic or anti-electromagnetic wave agents; and drying the second polymer. The method of claim 1, wherein the first polymer is a triacetate cellulose (TAC) or a polymethylmethacrylate (PMMA), and the first solvent system Glacial acetic acid, and/or wherein in the step of dissolving the first polymer using the first solvent, the ratio of the first polymer to the first solvent is 1:30. The recycling method as described in claim 1, wherein the second gathering The compound is polyethylene terephthalate (PET), and the second solvent is water, methanol or glacial acetic acid. The recovery method of claim 1, wherein the dissolving the first polymer using the first solvent comprises: heating the first polymer and the first solvent to 80 degrees Celsius; and stirring the first A polymer is allowed to continue with the first solvent for 45 minutes. The recovery method of claim 1, further comprising: distilling the mixed solution to separate the first solvent and the second solvent. The recovery method of claim 1, wherein after the first polymer is dissolved in the first solvent, the recovery method further comprises: separating the precipitated first polymer and the mixed solution; mixing one a pH adjuster and the precipitated first polymer neutralize the first polymer with an acid base; and recover the pH adjuster. The recovery method of claim 1, wherein after the step of drying the first polymer, the recycling method further comprises: mixing the dried first polymer with the first solvent to form the first Polymer solution; Mixing the first polymer solution with an acid solution to form a second polymer solution, wherein the first polymer is reacted into a third polymer; the acid and alkali neutralize the second polymer solution; and mixing the first The second polymer solution and the second solvent are used to precipitate the third polymer. An apparatus for recovering an optical film, comprising: a first processing tank for dissolving a first polymer of a waste optical film with a first solvent to form a first polymer solution, wherein the first solvent is insoluble a second polymer of the waste optical film, wherein after the first polymer is dissolved in the first solvent, by adding nano-grade inorganic particles, organic acrylic particles, antistatic agents or anti-electromagnetic agents Reducing the viscosity of the second polymer; a second treatment tank for mixing the first polymer solution and a second solvent to precipitate the first polymer, wherein the first polymer, the first solvent And mixing with the second solvent, wherein the first solvent and the second solvent form a mixed solution; and a dryer for drying the precipitated first polymer. The recycling device of claim 8, wherein the first polymer is cellulose triacetate or polymethyl methacrylate, and the first solvent is glacial acetic acid, and/or the first polymer The ratio to the first solvent is 1:30. The recycling apparatus of claim 8, wherein the second polymer is polyethylene terephthalate, and the second solvent is water, methanol or glacial acetic acid. The recycling device of claim 8, wherein the first processing tank is further configured to: heat the first polymer and the first solvent to 80 degrees Celsius; and stir the first polymer and the first The solvent lasted for 45 minutes. The recycling device of claim 8, further comprising: a distillation column for distilling the mixed solution to separate the first solvent and the second solvent. The recycling device of claim 8, wherein the second processing tank is further configured to: separate the precipitated first polymer and the mixed solution; and mix the first acid value adjusting agent and the first one of the precipitation The polymer neutralizes the first polymer with an acid or a base; wherein the recycling device further comprises: a conditioning agent tank for recovering the pH adjusting agent. The recycling device of claim 8, wherein the first processing tank is further used to: Mixing the dried first polymer with the first solvent to form the first polymer solution; mixing the first polymer solution with an acid solution to form a second polymer solution, wherein the first The polymer is esterified into a third polymer; and the second polymer solution is neutralized by the acid and the base; wherein the second treatment tank is further configured to: mix the second polymer solution and the second solvent to precipitate the first Three polymers.