JPS63178888A - Treatment of photoresist-containing waste liquid - Google Patents
Treatment of photoresist-containing waste liquidInfo
- Publication number
- JPS63178888A JPS63178888A JP62007449A JP744987A JPS63178888A JP S63178888 A JPS63178888 A JP S63178888A JP 62007449 A JP62007449 A JP 62007449A JP 744987 A JP744987 A JP 744987A JP S63178888 A JPS63178888 A JP S63178888A
- Authority
- JP
- Japan
- Prior art keywords
- waste liquid
- photoresist
- concentrated
- photoresist component
- component
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000007788 liquid Substances 0.000 title claims abstract description 109
- 239000002699 waste material Substances 0.000 title claims abstract description 103
- 229920002120 photoresistant polymer Polymers 0.000 title claims abstract description 79
- 238000011282 treatment Methods 0.000 title abstract description 24
- 239000012528 membrane Substances 0.000 claims abstract description 33
- 239000007787 solid Substances 0.000 claims abstract description 14
- 238000002485 combustion reaction Methods 0.000 claims abstract description 8
- 238000000034 method Methods 0.000 claims description 38
- 238000000108 ultra-filtration Methods 0.000 claims description 32
- 239000000126 substance Substances 0.000 claims description 13
- 238000006116 polymerization reaction Methods 0.000 claims description 8
- 230000001678 irradiating effect Effects 0.000 claims description 4
- 230000001737 promoting effect Effects 0.000 claims description 2
- 238000007711 solidification Methods 0.000 abstract description 3
- 230000008023 solidification Effects 0.000 abstract description 3
- 230000003247 decreasing effect Effects 0.000 abstract description 2
- 238000001914 filtration Methods 0.000 abstract description 2
- 239000000243 solution Substances 0.000 description 33
- 238000004519 manufacturing process Methods 0.000 description 13
- 239000000047 product Substances 0.000 description 13
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 11
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- 238000012545 processing Methods 0.000 description 8
- 239000003513 alkali Substances 0.000 description 7
- 238000011161 development Methods 0.000 description 6
- 239000000463 material Substances 0.000 description 6
- 239000011521 glass Substances 0.000 description 5
- 239000002253 acid Substances 0.000 description 4
- 239000002518 antifoaming agent Substances 0.000 description 4
- 239000003795 chemical substances by application Substances 0.000 description 4
- 238000001704 evaporation Methods 0.000 description 4
- 238000000926 separation method Methods 0.000 description 4
- 239000002904 solvent Substances 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 3
- 239000012141 concentrate Substances 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 3
- 230000008020 evaporation Effects 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 239000005416 organic matter Substances 0.000 description 2
- 239000012466 permeate Substances 0.000 description 2
- 229920002492 poly(sulfone) Polymers 0.000 description 2
- 238000003672 processing method Methods 0.000 description 2
- 238000001223 reverse osmosis Methods 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- NLHHRLWOUZZQLW-UHFFFAOYSA-N Acrylonitrile Chemical compound C=CC#N NLHHRLWOUZZQLW-UHFFFAOYSA-N 0.000 description 1
- 241000219122 Cucurbita Species 0.000 description 1
- 235000009852 Cucurbita pepo Nutrition 0.000 description 1
- 239000004642 Polyimide Substances 0.000 description 1
- MCMNRKCIXSYSNV-UHFFFAOYSA-N ZrO2 Inorganic materials O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 239000004480 active ingredient Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 238000011038 discontinuous diafiltration by volume reduction Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000005194 fractionation Methods 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000011147 inorganic material Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 230000003204 osmotic effect Effects 0.000 description 1
- RVTZCBVAJQQJTK-UHFFFAOYSA-N oxygen(2-);zirconium(4+) Chemical compound [O-2].[O-2].[Zr+4] RVTZCBVAJQQJTK-UHFFFAOYSA-N 0.000 description 1
- 238000006303 photolysis reaction Methods 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 239000002861 polymer material Substances 0.000 description 1
- 230000000379 polymerizing effect Effects 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 229920001059 synthetic polymer Polymers 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000013519 translation Methods 0.000 description 1
Landscapes
- Heat Treatment Of Water, Waste Water Or Sewage (AREA)
- Physical Water Treatments (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は、プリント基板製造工程、印刷工業。[Detailed description of the invention] [Industrial application field] The present invention is applicable to printed circuit board manufacturing process and printing industry.
半導体製造工業等より排出される廃液の処理方法に関す
る。特に、フォトレジスト成分含有廃液を濃縮する前処
理と電磁波または熱エネルギー照射により廃液を固化す
る処分方法に関する。This invention relates to a method for treating waste liquid discharged from the semiconductor manufacturing industry, etc. In particular, the present invention relates to a pretreatment method for concentrating a photoresist component-containing waste solution and a disposal method for solidifying the waste solution by electromagnetic waves or thermal energy irradiation.
［従来の技術］ 従来のプリント基板製造の廃液処理技術では。[Conventional technology] With conventional waste liquid treatment technology for printed circuit board manufacturing.
水溶性フォトレジストを含有する廃液は、第１図に示す
ように酸添加によりｐＨを下げ、溶解レジストを不溶化
し、固液分離した後９アルカリ剤でｐＨを中性にし、希
釈水により有機物の負荷を低減した後、生物処理、濾過
、活性戻吸着を行なうものであった。このような処理方
法では、多量の酸・アルカリを消費するとともに、大量
の希釈水と大型の単位処理装置を必要とするために廃液
の処理コストが極めて高いものであった。As shown in Figure 1, the pH of the waste liquid containing water-soluble photoresist is lowered by adding acid to insolubilize the dissolved resist, and after solid-liquid separation, the pH is made neutral with alkali agent 9, and organic substances are removed with diluted water. After reducing the load, biological treatment, filtration, and active back-adsorption were performed. Such a treatment method consumes a large amount of acid or alkali, and requires a large amount of dilution water and a large-sized unit treatment device, resulting in extremely high waste liquid treatment costs.
・亦、従来、このフォトレジスト含有廃液の処理法には
、逆浸透法によるものもあるが、これには１次のような
問題点がある。プリント基板製造より排出される廃液は
、無機質を２％程度含有しているため、高い濃縮倍率が
確保できない。即ち、浸透圧の上昇により５倍の濃縮の
程度が実用上の限界である。そのために、廃液の約１７
５程度の濃縮液が処理しなければならないものとして残
るものである。・In addition, conventional methods for treating this photoresist-containing waste liquid include reverse osmosis, but this method has the following problems. Since the waste liquid discharged from printed circuit board manufacturing contains about 2% inorganic substances, a high concentration ratio cannot be secured. That is, the practical limit is a 5-fold concentration due to an increase in osmotic pressure. Therefore, about 17
About 50% of the concentrate remains to be processed.
一方、フォトレジスト含有廃液に光エネルギー或いは熱
を与え、生成する不溶分を固液分離する方法、また、逆
に電磁波エネルギーで高分子フォトレジスト分を分解、
無害化する方法がある。然し乍ら、これらの方法は１重
合促進剤や光分解促進剤等の添加を必要とし、付与エネ
ルギーの必要とあいまって処理コストを高くする問題が
あった。On the other hand, there is a method of applying light energy or heat to photoresist-containing waste liquid and separating the generated insoluble content into solid and liquid, and conversely, a method of decomposing the polymeric photoresist content with electromagnetic energy.
There is a way to make it harmless. However, these methods require the addition of monopolymerization accelerators, photodecomposition accelerators, etc., which, together with the need for applied energy, poses a problem of increasing processing costs.
＝３一
本発明者らは廃液量と処理コストの大幅低減を可能にす
る第３図に示す廃液の回収再利用の方法を特許出願した
く特願昭６１−１７１８９４号〉。=31 The present inventors would like to apply for a patent for the method of collecting and reusing waste liquid shown in FIG. 3, which enables a significant reduction in the amount of waste liquid and processing cost.
この処理法では限外濾過膜で濃縮した濃縮液に酸を添加
しフォトレジスト成分を不溶化し、固液分離した後に、
逆浸透或いは紫外線分解及び活性炭吸着或いは生物処理
法を適用するものである。この濃縮液処理法は、濃縮液
量が大幅に減じているため処理コスト高に結びつかない
ものの、更に処理の簡便化が望まれていた。In this processing method, acid is added to the concentrated solution concentrated using an ultrafiltration membrane to insolubilize the photoresist components, and after solid-liquid separation,
Reverse osmosis, ultraviolet decomposition, activated carbon adsorption, or biological treatment methods are applied. Although this concentrated liquid processing method does not lead to high processing costs because the amount of concentrated liquid is significantly reduced, it has been desired to further simplify the processing.
［発明が解決しようとする問題点］
プリント基板製造で排出される現像廃液及び剥離廃液は
、水溶性フォトレジスト樹脂及び消泡剤等を溶解したア
ルカリ性廃液であり、また、ＣＯＤ、ＢＯＤが高く、廃
液処理コストも高いものである。廃液は全量処分しなけ
ればならなく、少しの減容では、コスト高を解決できな
い。これに対して９本発明は、廃液処理コストの低減さ
れた廃液処理方法を提供することを目的とする。また。[Problems to be Solved by the Invention] The developing waste liquid and stripping waste liquid discharged in printed circuit board manufacturing are alkaline waste liquids in which water-soluble photoresist resin, antifoaming agent, etc. are dissolved, and they have high COD and BOD. Waste liquid treatment costs are also high. The entire amount of waste liquid must be disposed of, and even a small volume reduction cannot solve the high cost. In contrast, it is an object of the present invention to provide a waste liquid treatment method with reduced waste liquid treatment costs. Also.
フォトレジスト成分含有廃液を薬剤を添加することなく
極めて簡便に且つ安価にフォトレジスト含有廃液を処理
できる方法を提供することをＩ」的とする。It is an object of the present invention to provide a method for processing a photoresist component-containing waste solution very easily and inexpensively without adding any chemicals to the photoresist component-containing waste solution.
［発明の構成コ
［問題点を解決するための手段］
本発明の要旨とするものは、フォトレジスト成分を含有
する廃液の処理方法おいて、フォトレジスト成分含有廃
液をフォトレジスト成分のみを排除する限外濾過膜によ
りフォトレジスト成分を濃縮し、得られた濃縮廃液に、
太陽光等の電磁波を照射し、または熱エネルギーを加え
、フォトレジスト成分を重合せしめ、固形物にして処理
することによるフォトレジスト含有廃液の処理方法であ
る。亦、得られた固形物を燃焼袋せて、その燃焼熱によ
り該濃縮廃液を更に蒸発せしめ、電磁波照射による重合
を促進せしめることができる。[Structure of the Invention [Means for Solving Problems] The gist of the present invention is to provide a method for treating waste liquid containing a photoresist component, in which only the photoresist component is removed from the waste liquid containing the photoresist component. The photoresist components are concentrated using an ultrafiltration membrane, and the resulting concentrated waste liquid is
This is a method for treating photoresist-containing waste liquid by irradiating electromagnetic waves such as sunlight or applying thermal energy to polymerize photoresist components and process them into a solid substance. Furthermore, the obtained solid matter can be placed in a combustion bag, and the concentrated waste liquid can be further evaporated by the heat of combustion, thereby promoting polymerization by electromagnetic wave irradiation.
［作用］
従来の廃液処理法では、廃液の全量を処理するが１本発
明による廃液処理法では、廃液自体を限外濾過により、
約１／１０〜１／２ｏ以上に濃縮し、その濃縮液に太陽
光などの電磁波または熱エネルギーを与え、含有フォト
レジスト成分などの有機物を重合させて固形分にし、固
形分は、自燃され、容易に処分され得るものである。[Function] In the conventional waste liquid treatment method, the entire amount of waste liquid is treated, but in the waste liquid treatment method according to the present invention, the waste liquid itself is treated by ultrafiltration.
Concentrate to approximately 1/10 to 1/2 o or more, apply electromagnetic waves such as sunlight or thermal energy to the concentrated liquid, polymerize the organic substances such as photoresist components contained therein, and make the solid content self-combustible. It can be easily disposed of.
限外濾過による廃液処理法では、現像、剥離廃液を各々
アルカリ性に保持しつ一つ、限外濾過膜を通して、濾過
し、これらフォトレジスト成分含有廃液は、フォトレジ
スト樹脂成分が、限外濾過膜を通過せずに、濃縮液とし
て残り、その他のアルカリ分、消泡剤等の有効添加成分
は限外濾過膜を自由に透過するため、透過液を現像液ま
たは剥離液としてもどし再び利用できる。従って、ａ縮
廃液はフォトレジスト成分を濃度高く含有し、原廃液址
の１／１０〜１／２０の程度にまで濃縮可能である。In the waste liquid treatment method using ultrafiltration, each of the developing and stripping waste liquids is kept alkaline and filtered through an ultrafiltration membrane. The permeated liquid remains as a concentrated liquid without passing through the ultrafiltration membrane, and other effective additives such as alkaline components and antifoaming agents freely pass through the ultrafiltration membrane, so the permeated liquid can be returned and reused as a developer or stripping liquid. Therefore, the a waste solution contains photoresist components at a high concentration, and can be concentrated to about 1/10 to 1/20 of the original waste solution.
水溶性フォトレジスト廃液は、プリント基板製造の場合
、 ＮａｔＣＯｓ 、 ＮａＯＨ或いはＫＯＨを１〜２
％含有するアルカリ性水溶液である。この廃液を分画分
子量５０００〜１００００の限外濾過膜に通しると、゛
ノオ］・レジストに起因する有機物の濃度は１．５重量
％程度から１５〜３０重量％にまで濃縮きれる。−・方
１分子量の小さい、フォトレジストの溶剤成分である無
機アルカリ剤は殆ど濃縮されずに、得られた濃縮液中に
は工ないし２％の含有率に留まるものである。In the case of printed circuit board manufacturing, water-soluble photoresist waste liquid contains 1-2% of NatCOs, NaOH or KOH.
It is an alkaline aqueous solution containing %. When this waste liquid is passed through an ultrafiltration membrane having a molecular weight cut off of 5,000 to 10,000, the concentration of organic matter originating from the ゛NO] resist can be concentrated from about 1.5% by weight to 15 to 30% by weight. The inorganic alkaline agent, which is a solvent component of photoresist and has a small molecular weight, is hardly concentrated and remains at a content of 1 to 2% in the obtained concentrated liquid.
フォトレジスト含有廃液は、フォトレジストの溶剤とし
てのアルカリが存在するために、アルカリを中和したｐ
Ｈ６以下で始めて重合し不溶分が析出するが１本発明に
より濃縮した液では、フォトレジスト成分がリッチにな
っているため高アルカリ性領域でも、水を含んだままで
容易に重合する性質を有し、何ら酸等の薬剤を添加する
ことなく太陽光などの電磁波または熱エネルギーの付与
によって容易に重合固化することが可能である。The photoresist-containing waste liquid contains alkali as a solvent for the photoresist, so the alkali is neutralized.
Polymerization begins and insoluble matter precipitates at temperatures below H6, but the concentrated solution according to the present invention is rich in photoresist components, so it has the property of easily polymerizing while still containing water, even in highly alkaline regions. It is possible to easily polymerize and solidify by applying electromagnetic waves such as sunlight or thermal energy without adding any chemicals such as acids.
重合、固化は、ｆｋ縮液の含水率が５０〜６０重量％付
近から生起し、含有水も含めて重合固化ができるために
従来法に見られるような固液分離の処理も必要ないもの
である。Polymerization and solidification occur when the water content of the FK condensate is around 50 to 60% by weight, and since the water content can be polymerized and solidified, there is no need for solid-liquid separation as seen in conventional methods. be.
本発明によるフォトレジスト成分濃縮廃液が。A concentrated waste liquid of photoresist components according to the present invention.
太陽光などの電磁波または熱エネルキー照射だけで容易
に重合され、フォトレジスト含有廃液を簡便に経済的に
処理できるためには以下の条件を満たすものでなければ
ならない。In order for photoresist-containing waste liquid to be easily polymerized by simply irradiating electromagnetic waves such as sunlight or thermal energy, and to be able to process photoresist-containing waste liquid simply and economically, it must satisfy the following conditions.
濃縮廃液は、アルカリ成分などの他の成分の含有レベル
が低く、主にフォトレジスト成分を含有しているもので
なければならない。そして１本発明により利用する限外
濾過膜は１次のようなものでなければならない。The concentrated waste liquid must contain mainly photoresist components, with low levels of other components such as alkaline components. The ultrafiltration membrane used in accordance with the present invention must be of the following order.
第１に限外濾過膜のモジュールは、処理すべきフォトレ
ジスト廃液がアルカリ性であるので、耐アルカリ性でな
（すればならない。First, the ultrafiltration membrane module must be alkali-resistant because the photoresist waste liquid to be treated is alkaline.
第２に、アルカリ性の廃液に溶解された無機質を透過し
、フォトレジスト成分を除くために、限外濾過膜の分画
分子量は、好適には５０００〜１００００の範囲である
。Secondly, the molecular weight cutoff of the ultrafiltration membrane is preferably in the range of 5,000 to 10,000 in order to pass through inorganic substances dissolved in the alkaline waste liquid and remove photoresist components.
これは２本発明方法によるフォトレジスト廃液の処理法
を、実際のフォトレジストの現像廃液及び剥離廃液の特
性を考慮して、この範囲が定められた。即ち、限外濾過
膜は一般に、ある一定の分子量範囲の溶質を除去する分
子量分画特性を有するが、この特性に基づくフォトレジ
ストの現像廃液及び剥離廃液中に含まれるフォトレジス
トに対する除去性能がすぐれたものでなければならない
。ここで除去性能とは、膜処理の供給原液成分濃度に対
する膜透過液成分濃度の低減率に相当し、換言すれば、
膜を透過しない成分濃度の比率である。This range was determined by considering the method of treating photoresist waste liquid according to the method of the present invention and the characteristics of actual photoresist developing waste liquid and stripping waste liquid. That is, ultrafiltration membranes generally have molecular weight fractionation characteristics that remove solutes within a certain molecular weight range, and based on these characteristics, ultrafiltration membranes have excellent removal performance for photoresist contained in photoresist development waste solutions and stripping waste solutions. It must be of the same type. Here, the removal performance corresponds to the reduction rate of the membrane permeate component concentration with respect to the concentration of the membrane treatment raw solution component; in other words,
It is the ratio of the concentration of components that do not pass through the membrane.
フォトレジスト成分を大部分濃縮でき、消泡剤及びアル
カリ成分をじゆうに透過できる範囲は。What is the range in which most of the photoresist components can be concentrated and the antifoaming agent and alkaline components can be passed through?
分画分子量が、５０００〜１ｏｏｏｏの範囲にあるもの
でなければならない。このような特性を有する限外濾過
膜を用いることによってフォトレジスト処理の現像廃液
及び剥離廃液中の有効成分たる消泡剤及びアルカリ成分
を経済的に回収することができる。一方、フォトレジス
ト成分は処理しやすい固形分として取り出すことができ
る。The molecular weight cutoff must be in the range of 5000 to 1oooo. By using an ultrafiltration membrane having such characteristics, it is possible to economically recover the antifoaming agent and alkaline components, which are the active ingredients in the development waste solution and stripping waste solution from photoresist processing. On the other hand, photoresist components can be extracted as solids that are easy to process.
従って１本発明により適合利用できる限外濾過膜モジュ
ールは、膜素材として金属酸化物の無機材例えば、二酸
化ジルコニウム系、及び合成高分子材の中で１例えば、
ポリスルホン系、ポリイミド系、アクリルニトリル系等
が良好である。Therefore, the ultrafiltration membrane module that can be used in accordance with the present invention includes, as membrane materials, metal oxide inorganic materials such as zirconium dioxide, and synthetic polymer materials such as:
Polysulfone type, polyimide type, acrylonitrile type, etc. are good.
プリント基板製造に用いるフォトレジストの感光の後に
、それを現像するため、即ち、フォトレジストを除去す
るための現像工程で使用される現像液、処理すべき現像
廃液、限外濾過された液の性質及び、プリント基板製造
で導体板等をエツチングした後、光重合したフォトレジ
ストを剥離するための剥離液、その剥離廃液、限外濾過
された液等の特性を第１表に示す。Characteristics of the developer used in the development process for developing the photoresist used in the manufacture of printed circuit boards after exposure, that is, for removing the photoresist, the developer waste to be treated, and the ultrafiltered solution. Table 1 shows the characteristics of the stripping solution used to strip photoresist photopolymerized after etching conductor plates and the like in the manufacture of printed circuit boards, the stripping waste solution, and the ultrafiltered solution.
以下余白
現像廃液を限外濾過により処理し、限外濾過膜を通過し
た透過液を再び使用するためには、前の現像処理でアル
カリ成分が消費きれて、ｐＨ値が低下しているために、
限外濾過膜通過液には、アルカリ液を補給してｐＨの調
整を行なう。亦、剥離液においても、同様にｐＨの調整
を行ない、限外濾過膜通過液を剥離液として戻す。Below, in order to process the margin development waste liquid by ultrafiltration and reuse the permeated liquid that has passed through the ultrafiltration membrane, the alkaline component has been consumed in the previous development process and the pH value has decreased. ,
The pH of the liquid passing through the ultrafiltration membrane is adjusted by replenishing the alkaline solution. In addition, the pH of the stripping solution is similarly adjusted, and the liquid passing through the ultrafiltration membrane is returned as the stripping solution.
再生現像液（７） ｐ Ｈｃ７）調整には、 Ｎａ ｔ
Ｃｏ ｓ 、ＮａＯＨ溶液を補給する。現像液中のＮ
ａイオンが増加すると、剥離工程で溶解すべきフォトレ
ジストまでが溶解する恐れがあるが、レジスト溶解前の
ｐＨに達するまでＮａ１ｌを加えるとともに膜濃縮廃液
量に対応してＮａ、ＣＯ，の補給量を設定することでＮ
ａイオンの蓄積を防止することができる。Regenerated developer (7) For pH Hc7) adjustment, use Na t
Replenish Cos, NaOH solution. N in developer
If the a ions increase, there is a risk that even the photoresist that should be dissolved in the stripping process will be dissolved.However, 1l of Na is added until the pH reaches the level before dissolving the resist, and the amount of Na, CO, and replenishment is adjusted according to the amount of membrane concentrated waste liquid. By setting N
Accumulation of a ions can be prevented.
再生剥離液の成分の調整は、ＮａＯＨ或いはＫＯＨ溶液
でｐＨを１４程度に調整することで十分である。It is sufficient to adjust the components of the regenerated stripping solution by adjusting the pH to about 14 with a NaOH or KOH solution.
本発明によるフォトレジスト成分含有廃液の処理方法で
は、現像廃液及び剥離廃液の両方を処理し、各々の系の
限外濾過膜からでるフォトレジスト成分の濃縮された濃
縮廃液を太陽光下に放置することにより重合せしめ、濃
縮廃液を固形化する。尚、太陽光線に限らず９人工光線
によっても重合せしめ得る。また、濃縮廃液に熱エネル
ギーを加え、更に蒸発・濃縮することにより廃液を重合
・固化することができる。In the method for treating photoresist component-containing waste liquid according to the present invention, both the developing waste liquid and the stripping waste liquid are treated, and the concentrated waste liquid containing the photoresist components coming out from the ultrafiltration membrane of each system is left under sunlight. This polymerizes and solidifies the concentrated waste liquid. Incidentally, polymerization can be effected not only by sunlight but also by artificial light. Further, by applying thermal energy to the concentrated waste liquid and further evaporating and concentrating it, the waste liquid can be polymerized and solidified.
本発明による廃液処理では、アルカリ調整、限外濾過膜
の種類及び数量の変更等により廃液に溶解しているフォ
トレジスト成分、その濃度の変化に対応する処理条件の
選択が必要である。In the waste liquid treatment according to the present invention, it is necessary to select processing conditions corresponding to changes in the photoresist components dissolved in the waste liquid and their concentrations by adjusting the alkali, changing the type and quantity of ultrafiltration membranes, etc.
この限外濾過膜によりフォトレジスト成分は。The photoresist components are filtered through this ultrafiltration membrane.
１０〜２０倍に濃縮され、ｆａ縮液のフォトレジストな
どの有機物濃度は、１５〜３０重量％に達することがで
きる。本発明は、この濃縮液に薬剤を加えることなく、
極めて簡便且つ安価に廃液の処理を行なうことができる
。Concentrated 10-20 times, the concentration of organic matter such as photoresist in the fa condensate can reach 15-30% by weight. The present invention does not add drugs to this concentrated solution,
Waste liquid can be treated extremely easily and inexpensively.
以上のように９本発明で、フォトレジスト含有廃液その
ものを、自燃し得る固形物として固化するには、フォト
レジストの溶剤成分例えば、アル力り成分及び重合に関
与しない低分子有機物（フォトレジストの分解物など）
の濃度を増加許せないで、レジスト成分などの有機物濃
度を１０重量％程度（当初の廃液濃度からは約１０倍濃
縮に相当する）以上に、濃縮しておくことが必要である
。この濃縮には高分子フォトレジスト成分のみを排除即
ち、１１！縮できる限外濾過膜を用いる。As described above, in order to solidify the photoresist-containing waste liquid itself as a self-combustible solid in the present invention, it is necessary to use photoresist solvent components such as alkaline components and low-molecular organic substances that do not participate in polymerization (photoresist solvent components). decomposition products, etc.)
It is necessary to concentrate the concentration of organic substances such as resist components to about 10% by weight or more (corresponding to about 10 times concentration from the initial concentration of waste liquid) without allowing an increase in the concentration of resist components. This concentration excludes only the polymeric photoresist components, ie, 11! Use a collapsible ultrafiltration membrane.
この濃縮液に太陽光線等の電磁波または熱エネルギーを
一定時間照射するのみで濃縮液自体が固化する。照射す
べき電磁波エネルギーは２通常太陽光線でよく、波長２
００〜４００ｎｍの紫外線を含むものが好適であり、フ
ォトレジスト成分水溶液の特性に適するものを用いる。Simply by irradiating this concentrated liquid with electromagnetic waves such as sunlight or thermal energy for a certain period of time, the concentrated liquid itself solidifies. The electromagnetic wave energy to be irradiated is usually sunlight, which has a wavelength of 2.
A material containing ultraviolet rays of 00 to 400 nm is suitable, and a material suitable for the characteristics of the photoresist component aqueous solution is used.
バット、プレートなどにいれて濃縮液に太陽光線を当て
放置すればよい。従って９重合固化物は、プレート中に
水を含んで固化析出し、容易にとりだせる。その固化物
は、自燃するために、燃やしその燃焼熱を回収する手段
を講しれば、更に、もとの濃縮液の蒸発、固化を促進す
ることができる。また、熱エネルギーを加える場合はド
ラムドライヤーなどによる間接加熱方式とし９重合固化
物はスクレーパ−で剥ぎ取る方式が好適である。また、
この場合前記した固化物の燃焼熱は加熱エネルギーの補
助として利用できる。このような本発明によるフォト、
レジスト成分含有廃液の処理システムを、第４図に示す
。All you have to do is put it in a vat, plate, etc. and leave it exposed to sunlight. Therefore, the 9-polymerized solidified product is solidified and precipitated while containing water in the plate, and can be easily taken out. Since the solidified product self-combusts, if a means is taken to recover the heat of combustion by burning it, the evaporation and solidification of the original concentrated liquid can be further promoted. In addition, when applying heat energy, it is preferable to use indirect heating using a drum dryer or the like, and to peel off the 9-polymerized solidified product with a scraper. Also,
In this case, the heat of combustion of the solidified material described above can be used as supplementary heating energy. Such a photo according to the present invention,
FIG. 4 shows a treatment system for resist component-containing waste liquid.
即ち、フォトレジスト成分含有廃液を限外濾過にかけ、
その膜透過液は回収しリサイクル使用或いは無害化して
処理し、透過せずに濃縮した液には太陽光線など電磁波
または熱エネルギーを付与し重合固化せしめ、フォトレ
ジスト成分などを処理する。固化したフォトレジスト成
分などよりなる固化物は自燃せしめ、その燃焼熱で更に
処理を経済的に効率化せしめる。That is, the waste liquid containing the photoresist component is subjected to ultrafiltration,
The liquid that permeates through the membrane is collected and recycled or treated to make it harmless, and the liquid that does not pass through and is concentrated is subjected to electromagnetic waves such as sunlight or thermal energy to polymerize and solidify, and process photoresist components and the like. The solidified material, such as the solidified photoresist component, self-combusts, and the heat of combustion makes the process more economical and efficient.
本発明による重合同化は、含水率５０〜６０重量％付近
で生じ、水分も含めて固化し、且つ容易に自燃する固化
物が得られる。従って、従来法のような固液分離等の処
理を必要と１．ない。The polymerization according to the present invention occurs at a water content of around 50 to 60% by weight, solidifies including water, and easily self-combustes. Therefore, treatments such as solid-liquid separation as in the conventional method are required.1. do not have.
次に本発明の処理法の実施例による実証テストを述べる
が７本発明は、これにより限定されるものではない。Next, a demonstration test using an example of the treatment method of the present invention will be described, but the present invention is not limited thereto.
［実施例１］
プリント基板製造工程より排出する水溶性フォトレジス
ト現像廃液（１％Ｎ ａ ｔ ＣＯｚ添加し、ｐＨ１０
，５に調整したもノテ、 ＴＯ０６０００ｍｇ／ｊりを
分画分子量１００００のポリスルホン膜で２０倍に濃縮
した液２００ｍｆｉを２００ｍｍＸ２５０ｍｍのガラス
製バット中で太陽光下に放置した。４時間で厚みが２ｍ
ｍ程度の固化物を得た。固化物は水分５５重量％であっ
た。この固化物の低位発熱量は４１００ｋｃａｌ／ｋｇ
で容易に自燃した。[Example 1] Water-soluble photoresist development waste solution discharged from the printed circuit board manufacturing process (1% Na t COz added, pH 10)
200 mfi of a solution prepared by concentrating TO06000 mg/j to 20 times using a polysulfone membrane with a molecular weight cutoff of 10000 was left under sunlight in a 200 mm x 250 mm glass vat. 2m thick in 4 hours
A solidified product of about 1.0 m was obtained. The solidified product had a moisture content of 55% by weight. The lower calorific value of this solidified product is 4100kcal/kg
It easily combusted.
［実施例２］
プリント基板製造工程より排出する水溶性フォトレジス
ト剥離廃液（２％ＫＯＨを添加し、ｐＨ１３，５に調整
したもので、ＴＯＣ１１０００ｍｇ／ｌ）を実施例１と
同一の限外濾過膜で１０倍濃縮した液２００ｍｊ２を２
００ｍｍＸ２５０ｍｍのガラス製バット中で太陽光下に
放置した。その結果３．５時間で実施例１と同様の固化
物を得た。固化物の水分量は、６０重量％であった。低
位発熱量は３６００ｋｃａｌ／ｋｇであった。この固形
物は、実施例１と同様に自燃した。[Example 2] Water-soluble photoresist stripping waste liquid discharged from the printed circuit board manufacturing process (adjusted to pH 13.5 by adding 2% KOH, TOC 11000 mg/l) was filtered through the same ultrafiltration membrane as in Example 1. 200 mj2 of the 10-fold concentrated solution
It was left under sunlight in a glass vat measuring 00 mm x 250 mm. As a result, a solidified product similar to that in Example 1 was obtained in 3.5 hours. The moisture content of the solidified product was 60% by weight. The lower calorific value was 3600 kcal/kg. This solid matter self-combusted in the same manner as in Example 1.
［２比較例１コ
実施例１と同し現像廃液２００ｍ１！を限外濾過での濃
縮を行なわずにそのままで２００ｍｍＸ２５０ｍｍのガ
ラスバット中で太陽光下に放置した。その結果、１２時
間放置したが含水率５２重量％となったが、固化物は認
められなかった。更に天日蒸発を継続した結果、１３時
間で乾固したが、殆ど白色の無機アルカリ剤に起因する
粉末状析出物しか残らなかった。[2 Comparative Examples 1 Same as Example 1 200 ml of developer waste! was left under sunlight in a 200 mm x 250 mm glass vat without being concentrated by ultrafiltration. As a result, the moisture content was 52% by weight after being left for 12 hours, but no solidified matter was observed. As a result of further continued solar evaporation, it was dried to solidity in 13 hours, but only an almost white powdery precipitate caused by the inorganic alkali agent remained.
［比較例２］
実施例１と同し現像廃液を実施例１と同じ限外濾過によ
り５倍に濃縮した液２００ｍｊ２を２００ｍｍＸ２５０
ｍｍのガラスバット中で太陽光下に放置した。その結果
、９時間放置したが含水率５５重量％となったが、固化
物は得られなかった。[Comparative Example 2] The same developer waste solution as in Example 1 was concentrated five times by the same ultrafiltration as in Example 1. 200 mj2 of the solution was placed in a 200 mm x 250
It was left under sunlight in a glass vat of 2.0 mm in size. As a result, the water content was 55% by weight after being left for 9 hours, but no solidified product was obtained.
更に天日蒸発を継続した結果、１０時間で乾固したが、
殆ど白色の無機アルカリ剤に起因する粉末状析出物しか
残らなかった。As a result of further solar evaporation, it became dry in 10 hours.
Only an almost white powdery precipitate caused by the inorganic alkaline agent remained.
［比較例３コ
実施例１と同じ現像廃液を実施例１と同し限外濾過で８
倍に濃縮した液２００ ｍ ｌを２００ｍｍＸ２５０ｍ
ｍのガラスバット中で太陽光下に放置した。その結果、
７時間放置したが部分的に固化物が得られたが、白色粉
末が混在する固形物であり、固化が不十分であった。[Comparative Example 3] The same developing waste solution as in Example 1 was subjected to ultrafiltration to
200 ml of the concentrated solution was placed in a 200 mm x 250 m
The sample was left exposed to sunlight in a glass vat of 500 mL. the result,
After being left for 7 hours, a partially solidified product was obtained, but the solid was mixed with white powder and was not sufficiently solidified.
［実施例３］
実施例１で用いた廃液と同一の現像廃液を限外濾過によ
り２０倍に濃縮して濃縮液を得、その濃縮液を遮光下で
１時間含水率５７重量％まで加熱蒸発した。その結果実
施例１と同様に固化し、自燃する固化物を得た。[Example 3] The same developer waste solution as that used in Example 1 was concentrated 20 times by ultrafiltration to obtain a concentrated solution, and the concentrated solution was heated and evaporated under light shielding for 1 hour to a water content of 57% by weight. did. As a result, a solidified product which solidified and self-combusted in the same manner as in Example 1 was obtained.
［発明の効果］
本発明のフォトレジスト含有廃液の処理方法は、高分子
フォトレジストのみを排除する限外濾過膜の濃縮液が重
合できるために。[Effects of the Invention] The method for treating photoresist-containing waste liquid of the present invention is because the concentrated liquid of the ultrafiltration membrane that excludes only the polymeric photoresist can be polymerized.
第１に、極めて簡便に安価にフォトレジスト廃液を処理
できる方法を提供できる５−と。First, 5- and 5- can provide a method for processing photoresist waste liquid extremely simply and inexpensively.
第２に、光または熱エネルギーを用いる重合のために何
等の薬剤を添加する必要がなく、廃液重合固化ができる
こと。Second, it is possible to polymerize and solidify waste liquid without the need to add any chemicals for polymerization using light or thermal energy.
第３に９重合固化したものは、容易に自燃するために従
来の処理法のような固液分離水の処理を必要としないこ
と。Thirdly, since the 9-polymerized and solidified material easily self-combustes, it does not require treatment of solid-liquid separated water as in conventional treatment methods.
第４に、廃液を濃縮したものを更に含水率を下げるため
に、この固化物の燃焼熱を利用して、効率化が図かれる
こと。Fourthly, in order to further reduce the moisture content of the concentrated waste liquid, efficiency can be improved by utilizing the combustion heat of this solidified product.
第４に、従って、短時間に且つ極めて低コストで廃液を
固化処理することができることなどの技術的効果が得ら
れた。Fourthly, technical effects such as being able to solidify waste liquid in a short time and at extremely low cost were obtained.
第１図は、従来のプリント基板製造の廃液処理のシステ
ムを示すフローシートである。
第２図は、従来のプリント基板製造の廃液処理のシステ
ムを示すフローシートである。
第３図は、先願の発明によるプリント基板製造の現像廃
液又は剥離廃液を処理するシステムを示す説明図である
。
第４図は１本発明によるフォトレジスト含有廃液の処理
システムの１例を示すフローシートである。
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Ｌ５ （資）Ｈ興 耶 ＨセFIG. 1 is a flow sheet showing a conventional waste liquid treatment system for manufacturing printed circuit boards. FIG. 2 is a flow sheet showing a conventional waste liquid treatment system for manufacturing printed circuit boards. FIG. 3 is an explanatory diagram showing a system for treating developing waste liquid or stripping waste liquid from printed circuit board manufacturing according to the invention of the prior application. FIG. 4 is a flow sheet showing an example of a treatment system for photoresist-containing waste liquid according to the present invention. Patent Applicant: Sumitomo Heavy Industries, Ltd. ±1P Miyo 5 ni 9 廿凶wa Heng Weir Lotto 1 Cheek 1 look 1 look
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Claims (3)
いて、 フォトレジスト成分含有廃液をフォトレジスト成分のみ
を排除する限外濾過膜によりフォトレジスト成分を濃縮
し、得られた濃縮廃液に、電磁波を照射し、フォトレジ
スト成分を重合せしめ、固形物にして処理することを特
徴とするフォトレジスト含有廃液の処理方法。(1) A method for treating waste liquid containing a photoresist component, in which the photoresist component is concentrated in the waste liquid containing the photoresist component using an ultrafiltration membrane that removes only the photoresist component, and electromagnetic waves are applied to the resulting concentrated waste liquid. A method for treating photoresist-containing waste liquid, which comprises irradiating the photoresist component to polymerize the photoresist component and converting it into a solid substance.
該濃縮廃液を更に蒸発せしめ、電磁波エネルギー照射に
よる重合を促進せしめる特許請求の範囲第１項記載のフ
ォトレジスト含有廃液の処理方法。(2) A method for treating a photoresist-containing waste liquid according to claim 1, wherein the obtained solid substance is combusted, and the concentrated waste liquid is further evaporated by the heat of combustion, thereby promoting polymerization by electromagnetic energy irradiation.
いて、 フォトレジスト成分含有廃液をフォトレジスト成分のみ
を排除する限外濾過膜によりフォトレジスト成分を濃縮
し、得られた濃縮廃液に、熱エネルギーを加え、固形物
にして処理することを特徴とするフォトレジスト含有廃
液の処理方法。(3) In a method for treating waste liquid containing a photoresist component, the photoresist component is concentrated in the waste liquid containing the photoresist component using an ultrafiltration membrane that removes only the photoresist component, and thermal energy is applied to the resulting concentrated waste liquid. 1. A method for treating photoresist-containing waste liquid, the method comprising adding and treating it as a solid substance.
Priority Applications (7)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62007449A JPS63178888A (en) | 1987-01-17 | 1987-01-17 | Treatment of photoresist-containing waste liquid |
| US07/076,372 US4786417A (en) | 1986-07-23 | 1987-07-22 | Management of photoresist materials containing waste solution |
| AT87306477T ATE81476T1 (en) | 1986-07-23 | 1987-07-22 | TREATMENT OF A WASTE SOLUTION CONTAINING PHOTORESIST MATERIALS. |
| KR1019870007965A KR950014323B1 (en) | 1986-07-23 | 1987-07-22 | Management of photoresist materials containing waste solution |
| EP87306477A EP0254550B1 (en) | 1986-07-23 | 1987-07-22 | Treatment of photoresist materials containing waste solution |
| DE8787306477T DE3782205T2 (en) | 1986-07-23 | 1987-07-22 | TREATING A WASTE SOLUTION CONTAINING PHOTORESIST MATERIALS. |
| CN87105308A CN1010555B (en) | 1986-07-23 | 1987-07-23 | Management of photoresist materials containing waste solution |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62007449A JPS63178888A (en) | 1987-01-17 | 1987-01-17 | Treatment of photoresist-containing waste liquid |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63178888A true JPS63178888A (en) | 1988-07-22 |
| JPH0314518B2 JPH0314518B2 (en) | 1991-02-26 |
Family
ID=11666146
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62007449A Granted JPS63178888A (en) | 1986-07-23 | 1987-01-17 | Treatment of photoresist-containing waste liquid |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63178888A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1992015633A2 (en) * | 1991-03-01 | 1992-09-17 | E.I. Du Pont De Nemours And Company | Improved management of waste solution containing photoresist materials |
| JPH10504662A (en) * | 1994-08-24 | 1998-05-06 | バイエル・コーポレーション | Method and apparatus for rejuvenating developer in plate development |
| WO2006137194A1 (en) * | 2005-06-22 | 2006-12-28 | Toagosei Co., Ltd. | Method and apparatus for removing organic film on substrate surface |
| JP2020196013A (en) * | 2015-02-23 | 2020-12-10 | 東京応化工業株式会社 | Liquid refining method, chemical liquid or cleaning liquid manufacturing method, filter media, and filter device |
| WO2021215442A1 (en) * | 2020-04-24 | 2021-10-28 | ニプロ株式会社 | Pretreatment method and pretreatment system for drainage |
-
1987
- 1987-01-17 JP JP62007449A patent/JPS63178888A/en active Granted
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1992015633A2 (en) * | 1991-03-01 | 1992-09-17 | E.I. Du Pont De Nemours And Company | Improved management of waste solution containing photoresist materials |
| WO1992015633A3 (en) * | 1991-03-01 | 1992-10-29 | Du Pont | Improved management of waste solution containing photoresist materials |
| JPH10504662A (en) * | 1994-08-24 | 1998-05-06 | バイエル・コーポレーション | Method and apparatus for rejuvenating developer in plate development |
| WO2006137194A1 (en) * | 2005-06-22 | 2006-12-28 | Toagosei Co., Ltd. | Method and apparatus for removing organic film on substrate surface |
| JPWO2006137194A1 (en) * | 2005-06-22 | 2009-01-08 | 東亞合成株式会社 | Method and apparatus for removing organic coating on substrate surface |
| JP2020196013A (en) * | 2015-02-23 | 2020-12-10 | 東京応化工業株式会社 | Liquid refining method, chemical liquid or cleaning liquid manufacturing method, filter media, and filter device |
| WO2021215442A1 (en) * | 2020-04-24 | 2021-10-28 | ニプロ株式会社 | Pretreatment method and pretreatment system for drainage |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0314518B2 (en) | 1991-02-26 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |