JP2004358380A

JP2004358380A - Coating apparatus

Info

Publication number: JP2004358380A
Application number: JP2003160636A
Authority: JP
Inventors: Takeaki Tsuda; 武明津田; Hiroshi Yoshiba; 洋吉羽
Original assignee: Dai Nippon Printing Co Ltd
Current assignee: Dai Nippon Printing Co Ltd
Priority date: 2003-06-05
Filing date: 2003-06-05
Publication date: 2004-12-24
Anticipated expiration: 2023-06-05
Also published as: JP4612284B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating apparatus which has a coating means for applying a liquid or pasty coating material on the surface of a substrate moving relatively to one direction and can cope even with an unexpected fluctuation by preventing an influence due to disturbance factors. <P>SOLUTION: This apparatus is provided with one or more state quantity detecting means for detecting the state quantity interrelated to the state of a coating bead, one or more state quantity changing means for changing the prescribed state quantity correspondingly to the prescribed controlled variable and a calculation part. In order to maintain the state of the coating bead so as to obtain the coating quality as reference, the state quantity of the coating bead is controlled by repeating in real time a series of processings consisting of the detection processing that the state quantity detecting means detects the state quantity, the arithmetic processing that the calculation part calculates the controlled variable corresponded to the state quantity obtained by the detection processing and the state quantity changing processing that the state quantity changing means changes the state quantity according to the controlled variable obtained by the arithmetic processing, in this order. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、マニホールド部とスリット形状の吐出口を有するダイヘッドを備えた塗布手段により、塗布材料をシート状あるいはウェブ状の基材の表面に塗布する塗布装置に関し、特に、塗布の均一性を確保できる塗布装置に関する。
【０００２】
【従来の技術】
従来、マニホールド部とスリット形状の吐出口を有するダイヘッド部を備え、マニホールド部への塗布材料の供給は、配管を介してポンプにより行なわれる。塗布手段（塗布アプリケーションとも言う）にて、液状またはペースト状の塗布材料を、これと相対的に一方向に移動する連続ウエブまたは枚葉基板等の被塗布材料（以下基材とも言う）に塗布を行う際、基材と塗布手段間に形成される塗布ビードは、さまざまな外乱により影響を受けることによって、不安定となり、塗布面に段ムラと呼ばれる基材流れ方向に直交する方向の膜厚ムラ（以下、リビングとも言う）や、縦スジまたはストリークと呼ばれる流れ方向に対して水平な膜厚ムラを生じてしまうことがあり、この対応が求められていた。
特に、塗布速度が速くなると顕著となり、ムラの発生が多くなる傾向がある。
【０００３】
塗布ビードの状態に影響を与える外乱原因の１つとしては、基材の移動に伴ない移動する同伴空気が挙げられる。
塗布速度が低い時には影響が小さいが、ある塗布程度を境として影響は大きくなり、基材の全面に均一な塗布膜を得ることが困難となる。
そこでこの対策として、従来からさまざまな方法が考案されてきた。
スライドコーティング装置におけるチャンバーを使用したバキュウーム方式もその１つである。
これは前記した塗布ビードが同伴空気で乱されることがないように、塗布ビード近傍にチャンバーとバキュウーム装置を設け、チャンバー側に同伴空気を吸い込み、後部からビードを吸引してビードを安定に保つことによって、ムラを防いで良好な塗布面を得る方式である。（米特許第３７３５７２９号参照）
尚、上記のような塗布ビード近傍のチャンバーとバキュウーム装置とを合せて、ここでは、以降、減圧手段と言う。
ダイコーティング装置においては、塗布ロールを高電界に保ち、塗布ダイと塗布ロール間に静電界を生じせしめ、静電界の印加により空気の同伴を防止して塗布ビードを安定させる方式が知られている。（特公昭４６ー２７４２２号公報参照）
【０００４】
また、同伴空気以外の外乱要因としては、被塗布材料表面の微小な凹凸、塗布材料の不均一性、温度や湿度による変化、液供給系の不安定性が挙げられる。
これらに対しては、定常的に発生するものである場合には、被塗布材料や塗布材料の種類変更や環境の安定化、液供給系の高精度化等により対策を行っている。
【０００５】
【特許文献１】
米特許第３７３５７２９
【特許文献１】
特公昭４６ー２７４２２号公報
【０００６】
【発明が解決しようとする課題】
上記のように、塗布ビードが同伴空気で乱されることがないように、スライドコーティング装置においては、塗布ビード近傍にチャンバーとバキュウーム装置を設けており、ダイコーティング装置においては、塗布ダイと塗布ロール間に静電界を生じせしめ、静電界の印加により空気の同伴を防止して塗布ビードを安定させる方法が採られているが、チャンバーを設けるバキュウーム方式の場合、塗布ビードが幅方向全域に渡ってバキュウームすることによって制御が可能であれば良いが、部分的に乱れているようなものでは対応が難しく、また、静電方式の場合は、静電界の強度を上げるにも限界があるため、塗布速度の最大値もこれに依存してしまうという問題があった。
また、これらの同伴空気対応策では、被塗布材料や塗布材料の種類変更や環境の安定化、液供給系の高精度化などの対策もペースター等による突発的な変動については対応することができないという問題もあった。
本発明は、これらに対応するもので、具体的には、マニホールド部とスリット形状の吐出口を有するダイヘッドを備えた塗布手段により、塗布材料をシート状あるいはウェブ状の基材の表面に塗布する塗布装置で、且つ、塗布ビード近傍にチャンバーとバキュウーム装置からなる減圧装置を設け、塗布ビードの状態への外乱要因の１つである同伴空気による定常的な影響を無くした塗布装置であって、被塗布材料や塗布材料の種類変更や環境の安定化、液供給系の高精度化などの対策しても発生するペースター等による突発的な変動についても対応することができる塗布装置を提供しようとするものである。
【０００７】
【課題を解決するための手段】
本発明の塗布装置は、マニホールド部とスリット形状の吐出口を有するダイヘッドを備えた塗布手段により、塗布材料をシート状あるいはウェブ状の基材の表面に塗布する塗布装置であって、塗布ビードの状態と相関性がある所定の状態量を検出する１つ以上の状態量検出手段と、塗布ビードの状態と相関性がある所定の状態量を所定の制御量に対応して変化させる１つ以上の状態量変化手段と、前記１つ以上の状態量検出手段から検出された状態量データを用いて、基準となる塗布品質になるように塗布ビードの状態を変化させるべく、対応する所定の各状態量変化手段をそれぞれ制御するための制御量を演算し、対応する所定の状態量変化手段へ送る演算部とを備えたもので、基準となる塗布品質になるように塗布ビードの状態を維持すべく、順に、状態量検出手段による状態量を検出する検出処理、演算部による前記検出処理により得られた状態量に対応した制御量を演算する演算処理、状態量変化手段による前記演算処理により得られた制御量により状態量を変化させる状態量変化処理、からなる一連の処理をリアルタイムに繰り返す、状態量制御を行うものであることを特徴とするものである。
そして、上記の塗布装置であって、塗布手段は塗布材料を定量供給するポンプを有し、ダイヘッドに装着された減圧手段、および基材に塗布された塗布膜厚を測定する膜厚計を備え、基材に塗布された塗布材料の膜厚の、所定の短期間および長期間での経時的変化において、膜厚の変化量と、基材の進行方向（速度ムラ）および基材に直交する方向（機械振動）の振動量とを、状態量として検出し，これらの状態量を用いて、塗布ビード内の圧力の変動状態を推算し、この圧力の変動を打消すような、状態量変化手段の制御量を演算し、演算されて得た制御量を、前記状態量変化手段に与えて制御するもので、前記状態量変化手段としてポンプもしくは隔膜等を用い、塗布ビード内の圧力の変動を打消すような、圧力信号を与えるものであることを特徴とするものである。
あるいは、上記の塗布装置であって，塗布手段は塗布材料を定量供給するポンプを有し、ダイヘッドに装着された減圧手段、および基材に塗布された塗布膜厚を測定する膜厚計を備え、基材に塗布された塗布材料の膜厚の、所定の短期間および長期間での経時的変化において、膜厚の変化量と、基材の進行方向（速度ムラ）および基材に直交する方向（機械振動）の振動量とを、状態量として検出し，これらの状態量を用いて、塗布ビード内の圧力の変動状態を推算し、この圧力の変動を打消すような、状態量変化手段の制御量を演算し、演算されて得た制御量を、前記状態量変化手段に与えて制御するもので、前記状態量変化手段としてダイヘッドに装着された減圧手段を用い、塗布ビード内の圧力の変動を打消すような、圧力を与えるものであることを特徴とするものである。
【０００８】
また、請求項２ないし３のいずれか１項に記載の塗布装置であって、状態量検出手段として、塗布手段の塗布ヘッドのマニホールド内の圧力、ダイヘッドに装着された減圧手段の圧力を、それぞれ測定する圧力計を取り付け、ダイヘッドに装着された減圧手段を、連続的に発生するリビングやストリーク不良を解消する為の、状態量変化手段として、連続的に生じる膜厚量の幅方向の偏差値と、ダイヘッドに装着している減圧手段の圧力値と、マニホールド内の圧力値とを、それぞれ状態量Ｑ１、Ｑ２、Ｑ３として検出し、状態量Ｑ１が基準値内に収まるように、状態量Ｑ２、Ｑ３を用いて、塗布ビード内の圧力状態を推算し、状態量変化手段としての減圧手段の（ポンプの）、リビングやストリーク不良を解消する為の制御量を演算し、演算されて得た制御量を、前記状態量変化手段である減圧手段（のポンプ）に与えて制御するものであることを特徴とするものである。
あるいは、請求項２ないし３のいずれか１項に記載の塗布装置であって、状態量検出手段として、塗布手段の塗布ヘッドのマニホールド内の圧力、ダイヘッドに装着された減圧手段の圧力を、それぞれ測定する圧力計を取り付け、且つ、塗布ギャップ量を調整できるギャップ制御手段を備え、前記ギャップ制御手段を、また、連続的に発生するリビングやストリーク不良を解消する為の、状態量変化手段とするもので、連続的に生じる膜厚量の幅方向の偏差値と、ダイヘッドに装着している減圧手段の圧力値と、マニホールド内の圧力値、塗布ギャップ量を状態量とを、それぞれ状態量Ｑ１、Ｑ２、Ｑ３、Ｑ４として検出し、状態量Ｑ１が基準値内に収まるように、状態量Ｑ２、Ｑ３、Ｑ４を用いて、塗布ビード内の圧力状態を推算し、状態量変化手段としてのギャップ制御手段の、リビングやストリーク不良を解消する為の制御量を演算し、演算されて得た制御量を、ギャップ制御手段に与えて制御するものであることを特徴とするものである。
【０００９】
また、請求項２ないし５のいずれか１項に記載の塗布装置であって、状態量検出手段として、塗布手段の塗布ヘッドと、塗布材料を塗布ヘッドに供給するためのポンプ部と、配管部とに、それぞれ、圧力計を取り付け、また、塗布された基材の膜厚を測定するための膜厚計を備えたもので、膜厚計にて測定された膜厚のデータをもとに、基材表面に塗布されない箇所である塗布ヌケがあると判断した場合、前記、塗布ヘッドの圧力計の圧力、ポンプ部の圧力計の圧力、および配管部の圧力計の圧力の、各状態量をもとに、状態量変化手段としての塗布材料を供給するためのポンプの制御量、あるいは、状態量変化手段としてのギャップ制御手段の制御量を演算し、状態量変化手段としての塗布材料を供給するポンプのポンプ流量を上げる、あるいは、状態量変化手段としてのギャップ制御手段により基材と塗布手段の塗布ヘッドとの距離を調整するものであることを特徴とするものであり、塗布材料が水溶性であり、膜厚計が水分計であることを特徴とするものである。
また、上記のいずれか１項に記載の塗布装置であって、状態量検出手段として、塗布材料の供給用タンクに塗布材料の粘度を測定するための粘度計を取り付け、供給用タンク内の塗布材料の粘度を状態量として得るもので、また、状態量変化手段として、供給用タンク内の塗布材料の温度を制御する温度制御手段を有するもので、状態量検出手段としての粘度計にて測定された粘度のデータをもとに、状態量変化手段としての温度制御手段により、粘度調整のパラメータである温度を制御し、供給用タンク内の塗布材料の粘度調整を行うものであることを特徴とするものである。
【００１０】
尚、先にも述べた通り、上記において、減圧手段とは、塗布ビードが同伴空気で乱されることがないように、その近傍に設ける減圧チャンバーと、これを吸引するバキュウーム装置を合せたもので、「ダイヘッドに装着された減圧手段」とは、その減圧チャンバー（単にチャンバーとも言う）をダイヘッドの外側に、塗布ビードが同伴空気で乱されることがないように、塗布ビード近傍に設けられた減圧手段を言う。
また、通常、上記の「基材に塗布された塗布材料の膜厚の、所定の短期間および長期間での経時的変化において、」における所定の短期間はｎｓｅｃ（ナノ秒）レベルで、所定の長期間は時間レベルである。
また、塗布手段の塗布材料を供給する手段としてのポンプは、ギア、隔膜、チューブ等の電気、空圧等を動力に用い、流量を変えることができるものであればよい。
【００１１】
【作用】
本発明の塗布装置は、このような構成にすることにより、具体的には、マニホールド部とスリット形状の吐出口を有するダイヘッドを備えた塗布手段により、塗布材料をシート状あるいはウェブ状の基材の表面に塗布する塗布装置で、且つ、塗布ビード近傍にチャンバーとバキュウーム装置からなる減圧装置を設け、塗布ビードの状態への外乱要因の１つである同伴空気による定常的な影響を無くした塗布装置であって、被塗布材料や塗布材料の種類変更や環境の安定化、液供給系の高精度化などの対策しても発生するペースター等による突発的な変動についても対応することができる塗布装置の提供を可能としている。
詳しくは、塗布ビードの状態と相関性がある所定の状態量を検出する１つ以上の状態量検出手段と、塗布ビードの状態と相関性がある所定の状態量を所定の制御量に対応して変化させる１つ以上の状態量変化手段と、前記１つ以上の状態量検出手段から検出された状態量データを用いて、基準となる塗布品質になるように塗布ビードの状態を変化させるべく、対応する所定の各状態量変化手段をそれぞれ制御するための制御量を演算し、対応する所定の状態量変化手段へ送る演算部とを備えたもので、基準となる塗布品質になるように塗布ビードの状態を維持すべく、順に、状態量検出手段による状態量を検出する検出処理、演算部による前記検出処理により得られた状態量に対応した制御量を演算する演算処理、状態量変化手段による前記演算処理により得られた制御量により状態量を変化させる状態量変化処理、からなる一連の処理をリアルタイムに繰り返す、状態量制御を行うものであることにより、これを達成している。
検出する状態量としては、例えば、
（１）塗布直前の基材については、基準面との距離、表面粗さ、表面の反射率、光沢度、色合い、または透明な材料の場合には、光の透過量等、
（２）塗布直後については、塗布膜厚や基準面と塗布表面との距離、または塗布膜中のある特定の成分に着目して、その成分の濃度、吸収スペクトル等、
（３）塗布手段については、各内部における塗布材料の圧力や温度、粘度、密度及びポンプ等駆動装置からの電気信号等、
（４）同伴空気による定常的な影響を無くすために、塗布ビード近傍にチャンバーとバキュウーム装置からなる減圧手段を、塗布ビード安定化手段として使用する場合には、検出データとして、吸引する圧力または空気量等、
が挙げられ、これらを適宜、目的に応じて使用する。
通常は、塗布ビードの状態と相関性がある状態量として、塗布膜厚量、膜厚偏差量、振動量、塗布ギャップ量、温度、圧力値、塗布材料の物性値、基材の物性値等が用いられる。
塗布材料として、溶液状あるいはペースト状のものまで種々の粘度のものが、水系、溶剤系を問わず適用できる。
被塗布材料である基材として、ガラス、金属、紙、プラスチックフィルム等のシート状あるいはウェブ状のものが適用できる。
【００１２】
例えば、状態量検出手段がｎ個、状態量変化手段がｋ個ある場合、請求項１に記載の発明の塗布装置の各部と状態量、制御量との関係は、概略で図１のようになる。
ここで、図１に示す塗布装置の動作を簡単に説明しておく。
尚、図１において太線の実線矢印は処理の方向を示し、Ｓ０〜Ｓ５は処理動作のステップを示すものである。
先ずはじめに、塗布ビードの状態を良好に維持すべく制御される系である、塗布する基材を含めた塗布手段１１０（Ｓ０）から、塗布ビードの状態と相関性がある所定の状態量を、状態量検出手段１〜状態量検出手段ｎにより検出し（Ｓ１）、検出データをそのまま得て、あるいは検出データから更に求めて、状態量１〜状態量ｍを得る。（Ｓ２）
次いで、演算手段１３０は、基準となる塗布品質になるように塗布ビードの状態を変化させるべく、状態量変化手段１〜状態量変化手段ｋの各制御量を演算し（Ｓ３）、得られた制御量１〜制御量ｋ（Ｓ４）を、それぞれ、対応する状態量変化手段へと送る。
次いで、状態量変化手段１〜状態量変化手段ｋはそれぞれの制御量に対応して、塗布ビードの状態を良好に維持すべく制御される系である、塗布する基材を含めた塗布手段１１０の、状態量を変化させる。（Ｓ５）
塗布する基材を含めた塗布手段１１０における状態量は各制御量に対応して、変化する。
更に、このような一連の処理（ステップＳ０〜Ｓ５）をリアルタイムに繰り返して行う。
このようにして、状態量の制御を行うものであり、一連の処理（ステップＳ０〜Ｓ５）の間隔を適当に決めることにより、塗布ビードの状態の突発的な不安定化に対応できる。
【００１３】
具体的には、塗布手段は塗布材料を定量供給するポンプを有し、ダイヘッドに装着された減圧手段、および基材に塗布された塗布膜厚を測定する膜厚計を備え、基材に塗布された塗布膜厚の、所定の短期間および長期間での経時的変化においての、膜厚の変化量と、基材の進行方向（速度ムラ）および基材に直交する方向（機械振動）の振動量とを、状態量として検出し，これらの状態量を用いて、塗布ビード内の圧力の変動状態を推算し、この圧力の変動を打消すような、状態量変化手段の制御量を演算し、演算されて得た制御量を、前記状態量変化手段に与えて制御するものの場合、膜厚変動を抑制することができるものとしている。
尚、前記状態量変化手段としてポンプもしくは隔膜等を用い、塗布ビード内の圧力の変動を打消すような、圧力信号を与えるものや、前記状態量変化手段としてダイヘッドに装着された減圧手段を用い、塗布ビード内の圧力の変動を打消すような、圧力を与えるものが挙げられ、
状態量のデータから、塗布される基材の外乱による振動の振幅および位相をとらえ、例えば、逆位相の信号をポンプに与えることにより、ポンプの脈動を制御し、膜厚変動を抑制することができる。
このための演算処理は、ＰＣ上のＣＰＵ等により行われる。
【００１４】
また、状態量検出手段として、塗布手段の塗布ヘッドのマニホールド内の圧力、ダイヘッドに装着された減圧手段の圧力を、それぞれ測定する圧力計を取り付け、ダイヘッドに装着された減圧手段を、連続的に発生するリビングやストリーク不良を解消する為の、状態量変化手段として、連続的に生じる膜厚量の幅方向の偏差値と、ダイヘッドに装着している減圧手段の圧力値と、マニホールド内の圧力値とを、それぞれ状態量Ｑ１、Ｑ２、Ｑ３として検出し、状態量Ｑ１が基準値内に収まるように、状態量Ｑ２、Ｑ３を用いて、塗布ビード内の圧力状態を推算し、状態量変化手段としての減圧手段の（ポンプの）、リビングやストリーク不良を解消する為の制御量を演算し、演算されて得た制御量を、前記状態量変化手段である減圧手段（のポンプ）に与えて制御するものである場合、
あるいは、状態量検出手段として、塗布手段の塗布ヘッドのマニホールド内の圧力、ダイヘッドに装着された減圧手段の圧力を、それぞれ測定する圧力計を取り付け、且つ、塗布ギャップ量を調整できるギャップ制御手段を備え、前記ギャップ制御手段を、また、連続的に発生するリビングやストリーク不良を解消する為の、状態量変化手段とするもので、連続的に生じる膜厚量の幅方向の偏差値と、ダイヘッドに装着している減圧手段の圧力値と、マニホールド内の圧力値、塗布ギャップ量を状態量とを、それぞれ状態量Ｑ１、Ｑ２、Ｑ３、Ｑ４として検出し、状態量Ｑ１が基準値内に収まるように、状態量Ｑ２、Ｑ３、Ｑ４を用いて、塗布ビード内の圧力状態を推算し、状態量変化手段としてのギャップ制御手段の、リビングやストリーク不良を解消する為の制御量を演算し、演算されて得た制御量を、ギャップ制御手段に与えて制御するものである場合には、連続的に発生するリビングやストリーク不良を解消を可能としている。
【００１５】
また、状態量検出手段として、塗布手段の塗布ヘッドと、塗布材料を塗布ヘッドに供給するためのポンプ部と、配管部とに、それぞれ、圧力計を取り付け、また、塗布された基材の膜厚を測定するための膜厚計を備えたもので、膜厚計にて測定された膜厚のデータをもとに、基材表面に塗布されない箇所である塗布ヌケがあると判断した場合、前記、塗布ヘッドの圧力計の圧力、ポンプ部の圧力計の圧力、および配管部の圧力計の圧力の、各状態量をもとに、状態量変化手段としての塗布材料を供給するためのポンプの制御量、あるいは、状態量変化手段としてのギャップ制御手段の制御量を演算し、状態量変化手段としての塗布材料を供給するポンプのポンプ流量を上げる、あるいは、状態量変化手段としてのギャップ制御手段により基材と塗布手段の塗布ヘッドとの距離を調整するものである場合には、基材表面に塗布されない箇所である塗布ヌケの発生の防止を可能としている。
尚、塗布材料が水溶性である場合には、膜厚計として水分計が適用できる。
【００１６】
また、状態量検出手段として、塗布材料の供給用タンクに塗布材料の粘度を測定するための粘度計を取り付け、供給用タンク内の塗布材料の粘度を状態量として得るもので、また、状態量変化手段として、供給用タンク内の塗布材料の温度を制御する温度制御手段を有するもので、状態量検出手段としての粘度計にて測定された粘度のデータをもとに、状態量変化手段としての温度制御手段により、粘度調整のパラメータである温度を制御し、供給用タンク内の塗布材料の粘度調整を行うものである場合には、供給用タンク内の塗布材料の粘度調整を容易に行うことを可能としている。
【００１７】
塗布手段としては、ロールコート、カーテンコート、スライドコート、ダイコートの各方式は問わない、前計量により、膜厚を塗布材料（単に液とも言う）供給装置の流量により変えることができるものであればよい。
膜厚計としては、膜厚が、所望の精度で計れれば特に限定されないが、計測により塗布品質を損なわないものが好ましく、塗布材料が水溶性であるものを用いる場合には、膜厚計として水分計が挙げられる。
水分計は塗布後の塗布材料内の水分量を赤外線等を利用して測定するもので、予め得ている水分量と膜厚の関係のデータから水分量を知ることにより、膜厚を得るものである。
【００１８】
本発明の塗布装置は、紙、樹脂フィルム、金属箔等のウェブまたは板状のガラス、金属、樹脂等の枚葉基材を被塗布材料（基材とも言う）とし、塗布材料として、粘度の低い液状のものから粘度の高いペースト状のものまで、水系、溶剤系を問わず、また粒子を含むものについて適用してた場合、塗布した面を何らかの手段で検出することさえ可能であれば、有効で、突発的な外乱にも対応できる。
また、塗布技術分野も特に限定はされない。
【００１９】
【発明の実施の形態】
本発明の塗布装置の実施の形態例を図に基づいて説明する。
図２は本発明の塗布装置の実施の形態の１例の一部を詳しく示した概略構成図で、図３（ａ）〜図３（ｃ）は各種コーティング方式における塗布ビードと塗布ビード安定化装置を説明するための塗布ヘッド部近くの塗布状態を示した図である。
尚、図２において太線の実線矢印は状態量のデータの流れの方向、太線の点線矢印は制御の方向を示し、また、図２における細線矢印、図３における太線矢印は、基材の進行方向を示している。
図２において、２１０は塗布ヘッド（ダイヘッド）、２１１はマニホールド部、２１２はスリット形状の吐出口（単にスリットとも言う）、２２１はポンプ、２３１は搬送系コントローラ、２３２は搬送ロール、２４１はバキューム装置、２４２はチャンバー、２５０は状態量、２５１は膜厚計、２５１ａは測定ヘッド、２５２はレーザ変位計、２５２ａは測定ヘッド、２６０は演算部（演算制御部あるいは塗布制御部とも言う）、２７０は塗布材料、２８０は基材であり、
図３において、１１は塗布ヘッド、１１ａはマニホールド部、１１ｂはスリット部、１２は基材、１３は塗布材料、１３Ｂは塗布ビード、２１は塗布ヘッド、２１ａはマニホールド部、２１ｂはスリット部、２２は基材、２３は塗布材料、２３Ｂは塗布ビード、２５は吸引チャンバー、３１は塗布ヘッド、３１ａはマニホールド部、３１ｂはスリット部、３２は基材、３３は塗布材料、３３Ｂは塗布ビードである。
【００２０】
本発明の塗布の実施の形態の１例を、図２に基づいて説明する。
本例は、一方向に移動する基材２８０の表面に、液状またはペースト状の塗布材料２７０を塗布する塗布手段として、マニホールド部２１１とスリット形状の吐出口２１２を有するダイヘッドからなる塗布ヘッド２１０、塗布材料供給用のポンプ２２１やタンク（図示していない）を含む塗布材料供給部、搬送系コントローラ２３１、搬送ロール２３２を有する基材搬送部を備え、且つ、塗布ビードを同伴空気で乱されずに定常的に安定化する手段として吸引チャンバー２４２、バキューム装置２４１からなる減圧手段を備えた塗布装置で、マニホールド部２１１への塗布材料２７０の供給を、配管（図示していない）を介してポンプ２２１により行うものである。
そして、第１の状態量検出手段として、膜厚計２５１、測定ヘッド２５１ａを有する膜厚測定手段を備え、第２の状態量検出手段として、測定ヘッド２５１ａ、レーザ変位計２５２を有する変位量検出部を備えたもので、第１の状態量検出手段により、基材２８０に塗布された塗布材料２７０の膜厚変化を測定して、膜厚変化のデータを状態量として得、また、第２の状態量検出手段により、塗布前の基材の、基材進行方向と垂直な変位量を検出して、これを状態量として得、更に、演算部２６０により、検出され得られた膜厚変化のデータと、基材２８０の変位量のデータから、塗布される基材２８０の外乱による振動の振幅および位相をとらえ、これを打ち消すようような圧力信号を、状態量変化手段としての塗布材料供給用のポンプ２２１に生じせしめる制御量を演算し、該制御量を状態量変化手段としてのポンプ２２１に与え、膜厚変動を抑制するもので、この一連の制御を、繰り返しリアルタイムで行うものである。
【００２１】
また、本例の塗布装置は、図示してはいないが、更に、第３状態量検出手段として、塗布手段の塗布ヘッド２１０のマニホールド２１１には圧力計を取り付け、塗布材料２７０を塗布ヘッド２１０に供給するためのポンプ２２１および配管部（図示していない）にも、それぞれ、圧力計を取り付けたものであり、前記各部の圧力値を状態量として得るものである。
そして、第１の状態量検出手段としての膜厚計２５１、測定ヘッド２５１ａを有する膜厚測定手段にて測定された膜厚変化のデータを基に、基材２８０の表面に塗布されない箇所である塗布ヌケがあると判断した場合、塗布ヘッド２１０のマニホールド２１１の圧力計、ポンプ２２１および配管部の圧力計の圧力値を参照して、ポンプ流量が足らないと判定できればポンプ流量を上げ、ポンプ流量が足りていると判定できれば、基材１８０と塗布手段１００の塗布ヘッド１１０との距離を最適化するギャップ制御を行うもので、この一連の制御を、繰り返しリアルタイムで行うものである。
上記では、ポンプ流量を変化させる流量制御手段、ギャップ量の制御を行うギャップ制御手段が、塗布ヌケがある場合における状態量変化手段である。
【００２２】
また、本例の塗布装置においては、図示はしてはいないが、第４の状態量検出手段として、塗布材料２７０の供給用タンク（図示していない）に塗布材料２７０の粘度を測定するための粘度計（図示していない）を取り付けており、供給用タンク内の塗布材料２７０の粘度変化のデータを状態量として得るもので、状態検出手段から得た粘度計にて測定された粘度変化のデータをもとに、状態量変化手段としての供給用タンクの加熱用ヒータ（図示していない）を用い、粘度調整のパラメータである温度を制御し、供給用タンク内の塗布材料の粘度調整を行う。
勿論、この一連の制御を、繰り返しリアルタイムで行う。
上記では、加熱用ヒータが状態量変化手段である。
【００２３】
また、本例の塗布装置は、ダイヘッドに装着された減圧手段を、連続的に発生するリビングやストリーク不良を解消する為の、状態量変化手段としているもので、連続的に生じる膜厚量の幅方向の偏差値と、ダイヘッドに装着している減圧手段の圧力値と、マニホールド内の圧力値とを、それぞれ状態量Ｑ１、Ｑ２、Ｑ３として検出し、状態量Ｑ１が基準値内に収まるように、状態量Ｑ２、Ｑ３を用いて、塗布ビード内の圧力状態を推算し、状態量変化手段としての減圧手段のポンプの、リビングやストリーク不良を解消する為の制御量を演算し、演算されて得た制御量を、前記状態量変化手段である減圧手段のポンプに与えて制御するものである。
本例では、リビングやストリーク不良を解消する為の状態量変化手段としての減圧手段のポンプを用いているが、リビングやストリーク不良を解消する為の状態量変化手段としてのギャップ制御手段とすることもできる。
この場合には、例えば、連続的に生じる膜厚量の幅方向の偏差値と、ダイヘッドに装着している減圧手段の圧力値と、マニホールド内の圧力値、塗布ギャップ量を状態量とを、それぞれ状態量Ｑ１、Ｑ２、Ｑ３、Ｑ４として検出し、状態量Ｑ１が基準値内に収まるように、状態量Ｑ２、Ｑ３、Ｑ４を用いて、塗布ビード内の圧力状態を推算し、状態量変化手段としてのギャップ制御手段の、リビングやストリーク不良を解消する為の制御量を演算し、演算されて得た制御量を、ギャップ制御手段に与えて制御する。
【００２４】
尚、本発明の塗布装置に適用できる塗布方式としては、先にも述べた通り、図３（ａ）にヘッド部を拡大して示す、実施の形態例の塗布装置と同様の、ダイヘッドからなる塗布ヘッド１１０を用いたダイコートに限定されない。
図３（ｂ）に示すスライドコートや、図３（ｃ）に示すカーテンコートも適用できる。
いずれの方式についても、図３（ｂ１）に１例を示すように、基材の塗布後方側に吸引チャンバー２５を配設することにより、定常的な塗布ビードの安定化を計ることができるが、これだけでは、突発的な外乱には対応できない。
いずれの方式についても、本発明のような構成にすることにより、突発的な外乱にも対応できる塗布装置とすることができる。
【００２５】
また、制御する状態量によっては、例えば、前述のタンク内の塗布材料の粘度のように、単に、状態量の値が増えていれば減じる、減じていれば増やすような制御を行うこともあるが、予め塗布品質に対応した状態量の組みを用意しておき、適当な状態量の組みになるように制御し、塗布ビードを安定化してもよい。
【００２６】
【発明の効果】
本発明は、上記のように、マニホールド部とスリット形状の吐出口を有するダイヘッドを備えた塗布手段により、塗布材料をシート状あるいはウェブ状の基材の表面に塗布する塗布装置で、且つ、塗布ビード近傍にチャンバーとバキュウーム装置からなる減圧装置を設け、塗布ビードの状態への外乱要因の１つである同伴空気による定常的な影響を無くした塗布装置であって、被塗布材料や塗布材料の種類変更や環境の安定化、液供給系の高精度化などの対策しても発生する突発的な変動についても対応することができる塗布装置の提供を可能とした。
【図面の簡単な説明】
【図１】本発明の塗布装置の１例の各部と状態量、制御量との関係を示した概略図である。
【図２】本発明の塗布装置の実施の形態の１例の一部を示した概略構成図である。
【図３】図３（ａ）〜図３（ｃ）は各種コーティング方式における塗布ビードと塗布ビード安定化装置を説明するための塗布ヘッド部近くの塗布状態を示した図で、図３（ｂ１）は、図３（ｂ）において更に吸引チャンバーを装着した図である。
【符号の説明】
１１０塗布手段（塗布する基材を含む）
１２０状態量検出手段
１３０演算手段
１４０状態量変化手段
２１０塗布ヘッド（ダイヘッド）
２１１マニホールド部
２１１、２１２スリット形状の吐出口（単にスリットとも言う）
２２１ポンプ
２３１搬送系コントローラ
２３２搬送ロール
２４１バキューム装置
２４２チャンバー
２５０状態量
２５１膜厚計
２５１ａ測定ヘッド
２５２レーザ変位計
２５２ａ測定ヘッド
２６０演算部（演算制御部あるいは塗布制御部とも言う）
２７０塗布材料
２８０基材
１１塗布ヘッド
１１ａマニホールド部
１１ｂスリット部
１２基材
１３塗布材料
１３Ｂ塗布ビード
２１塗布ヘッド
２１ａマニホールド部
２１ｂスリット部
２２基材
２３塗布材料
２３Ｂ塗布ビード
２５吸引チャンバー
３１塗布ヘッド
３１マニホールド部
３１ｂスリット部
３２基材
３３塗布材料
３３Ｂ塗布ビード[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a coating apparatus for coating a coating material on the surface of a sheet-shaped or web-shaped substrate by a coating unit having a die head having a manifold portion and a slit-shaped discharge port, and in particular, to ensure uniformity of coating. It relates to a coating device that can be used.
[0002]
[Prior art]
Conventionally, a manifold section and a die head section having a slit-shaped discharge port are provided, and the supply of the coating material to the manifold section is performed by a pump via a pipe. Applying a liquid or paste-like coating material to a coating material (hereinafter also referred to as a base material) such as a continuous web or a single-wafer substrate which moves in one direction relative to the coating material by a coating means (also referred to as a coating application). When performing, the coating bead formed between the substrate and the coating means becomes unstable by being affected by various disturbances, the film thickness in the direction orthogonal to the substrate flow direction called step unevenness on the coating surface In some cases, unevenness (hereinafter, also referred to as “living room”) or unevenness in film thickness, which is called vertical streak or streak, occurs in the direction of flow, has been demanded.
In particular, the higher the coating speed, the more remarkable the unevenness tends to occur.
[0003]
One of the causes of disturbance that affects the state of the coating bead is entrained air that moves as the substrate moves.
The effect is small when the coating speed is low, but the effect becomes large after a certain coating degree, making it difficult to obtain a uniform coating film on the entire surface of the base material.
Therefore, various methods have conventionally been devised as this measure.
A vacuum system using a chamber in a slide coating apparatus is one of them.
This is to provide a chamber and a vacuum device near the coating bead, suck the entrained air into the chamber side, and suck the bead from the rear to keep the bead stable so that the coating bead is not disturbed by the entrained air. This is a method of obtaining a good coated surface while preventing unevenness. (See U.S. Pat. No. 3,735,729)
The chamber near the application bead and the vacuum apparatus as described above are hereinafter referred to as a decompression means.
In a die coating apparatus, a method is known in which a coating roll is maintained at a high electric field, an electrostatic field is generated between a coating die and a coating roll, and application of the electrostatic field prevents air entrainment to stabilize a coating bead. . (See Japanese Patent Publication No. 46-27422)
[0004]
Disturbance factors other than the entrained air include minute irregularities on the surface of the material to be coated, unevenness of the coating material, changes due to temperature and humidity, and instability of the liquid supply system.
If these occur regularly, countermeasures are taken by changing the type of the material to be applied or the applied material, stabilizing the environment, and increasing the accuracy of the liquid supply system.
[0005]
[Patent Document 1]
US Patent No. 3,735,729
[Patent Document 1]
Japanese Patent Publication No. 46-27422
[0006]
[Problems to be solved by the invention]
As described above, in the slide coating device, a chamber and a vacuum device are provided near the coating bead so that the coating bead is not disturbed by the entrained air, and the coating die and the coating roll are provided in the die coating device. A method has been adopted in which a static electric field is generated in between to prevent the entrainment of air by applying the static electric field to stabilize the coating bead.However, in the case of a vacuum system in which a chamber is provided, the coating bead extends over the entire width direction. It is only necessary to be able to control by vacuuming, but it is difficult to cope with partial disturbance, and in the case of the electrostatic method, there is a limit in increasing the strength of the electrostatic field, so coating is difficult. There is a problem that the maximum value of the speed also depends on this.
In addition, these countermeasures against entrained air cannot respond to sudden fluctuations caused by pasters, etc., such as changing the type of coating material or coating material, stabilizing the environment, and increasing the accuracy of the liquid supply system. There was also a problem.
The present invention corresponds to these, and specifically, applies a coating material to the surface of a sheet-like or web-like substrate by a coating unit having a die head having a manifold portion and a slit-shaped discharge port. A coating apparatus, and a coating apparatus provided with a decompression device consisting of a chamber and a vacuum device in the vicinity of the coating bead, and eliminating a steady influence of entrained air which is one of the disturbance factors to the state of the coating bead, Even if measures such as changing the type of coating material or coating material, stabilizing the environment, and improving the precision of the liquid supply system are provided, it is intended to provide a coating apparatus that can respond to sudden fluctuations caused by pasters and the like. Is what you do.
[0007]
[Means for Solving the Problems]
The coating device of the present invention is a coating device that applies a coating material to the surface of a sheet-shaped or web-shaped substrate by a coating unit having a die head having a manifold portion and a slit-shaped discharge port, and includes a coating bead. One or more state quantity detecting means for detecting a predetermined state quantity correlated with the state; and one or more means for changing the predetermined state quantity correlated with the state of the application bead in accordance with a predetermined control amount Using the state quantity data detected by the one or more state quantity detecting means, and changing the state of the coating bead so that the coating quality becomes a reference coating quality, by using a corresponding predetermined quantity. A calculation unit for calculating a control amount for controlling each of the state quantity changing means and sending the control quantity to the corresponding predetermined state quantity changing means, and maintaining a state of the coating bead so as to be a reference coating quality. You In order, a detection process for detecting a state amount by the state amount detection means, a calculation process for calculating a control amount corresponding to the state amount obtained by the detection process by the calculation unit, and the calculation process by the state amount changing means are sequentially performed. It is characterized by performing state quantity control in which a series of processes consisting of a state quantity change process of changing a state quantity by a given control amount is repeated in real time.
In the above-described coating apparatus, the coating unit includes a pump for supplying a constant amount of the coating material, a pressure reducing unit attached to the die head, and a thickness gauge for measuring a coating thickness applied to the substrate. In a time-dependent change in the film thickness of the coating material applied to the base material over a predetermined short period and long period, the amount of change in the film thickness is perpendicular to the direction of travel of the base material (uneven speed) and the base material. The amount of vibration in the direction (mechanical vibration) is detected as a state quantity, and using these state quantities, the fluctuation state of the pressure in the coating bead is estimated, and the state quantity change that cancels this pressure fluctuation The control amount of the means is calculated, and the calculated control amount is given to the state amount changing means for control. Using a pump or a diaphragm as the state amount changing means, the pressure fluctuation in the application bead is changed. To give a pressure signal that cancels out And it is characterized in and.
Alternatively, in the above-mentioned coating apparatus, the coating means includes a pump for supplying a constant amount of the coating material, a pressure reducing means mounted on a die head, and a thickness gauge for measuring a coating thickness applied to the substrate. In a time-dependent change in the film thickness of the coating material applied to the base material over a predetermined short period and long period, the amount of change in the film thickness is perpendicular to the direction of travel of the base material (uneven speed) and the base material. The amount of vibration in the direction (mechanical vibration) is detected as a state quantity, and using these state quantities, the fluctuation state of the pressure in the coating bead is estimated, and the state quantity change that cancels this pressure fluctuation The control amount of the means is calculated, and the control amount obtained by the calculation is given to the state amount changing means for control. Using the pressure reducing means attached to the die head as the state amount changing means, Apply pressure to cancel pressure fluctuation It is characterized in that it.
[0008]
Further, in the coating apparatus according to any one of claims 2 to 3, the state quantity detecting means includes a pressure in a manifold of a coating head of the coating means and a pressure of a pressure reducing means attached to a die head, respectively. Attach a pressure gauge to measure, and use the pressure reducing means attached to the die head as a state quantity changing means to eliminate continuous living and streak defects. And the pressure value of the pressure reducing means mounted on the die head and the pressure value in the manifold are detected as state quantities Q1, Q2 and Q3, respectively, and the state quantity Q2 is set so that the state quantity Q1 falls within the reference value. , Q3, the pressure state in the coating bead is estimated, and the control amount of the pressure reducing means (of the pump) as the state amount changing means for eliminating the living and streak defects is calculated. A control amount obtained by the, is characterized in that it is intended to control given to pressure reducing means (pump) is the state quantity changing means.
Alternatively, the coating apparatus according to any one of claims 2 to 3, wherein the state amount detecting means includes a pressure in a manifold of a coating head of the coating means and a pressure of a pressure reducing means mounted on a die head, respectively. A pressure gauge to be measured is attached, and gap control means for adjusting the application gap amount is provided, and the gap control means is used as a state quantity changing means for eliminating living and streak defects that occur continuously. The deviation value in the width direction of the continuously generated film thickness amount, the pressure value of the pressure reducing means mounted on the die head, the pressure value in the manifold, and the state amount of the application gap amount are each expressed by a state amount Q1. , Q2, Q3, and Q4, and estimate the pressure state in the application bead using the state quantities Q2, Q3, and Q4 so that the state quantity Q1 falls within the reference value. The gap control means as a changing means calculates a control amount for eliminating living and streak defects, and gives the calculated control amount to the gap control means to control the gap control means. It is.
[0009]
The coating apparatus according to claim 2, wherein the state quantity detecting unit includes a coating head of the coating unit, a pump unit for supplying the coating material to the coating head, and a piping unit. And a pressure gauge, respectively, and a thickness gauge for measuring the thickness of the coated base material, and based on the thickness data measured by the thickness gauge. When it is determined that there is a coating drop which is a portion that is not coated on the surface of the base material, the respective state quantities of the pressure of the pressure gauge of the coating head, the pressure of the pressure gauge of the pump section, and the pressure of the pressure gauge of the piping section Based on the above, the control amount of the pump for supplying the coating material as the state quantity changing means or the control amount of the gap control means as the state quantity changing means is calculated, and the coating material as the state quantity changing means is calculated. Increase the pump flow rate of the pump to be supplied. Alternatively, the distance between the substrate and the coating head of the coating means is adjusted by a gap control means as a state quantity changing means, wherein the coating material is water-soluble, Is a moisture meter.
Further, in the coating apparatus according to any one of the above, a viscometer for measuring the viscosity of the coating material is attached to the coating material supply tank as a state quantity detecting unit, and the coating in the supply tank is performed. It obtains the viscosity of the material as a state quantity, and has a temperature control means for controlling the temperature of the coating material in the supply tank as a state quantity changing means, and is measured by a viscometer as a state quantity detecting means. Based on the obtained viscosity data, a temperature control means as a state quantity changing means controls a temperature which is a parameter of the viscosity adjustment to adjust the viscosity of the coating material in the supply tank. It is assumed that.
[0010]
As described above, in the above description, the decompression means is a combination of a decompression chamber provided in the vicinity thereof and a vacuum device for sucking the same so that the coating bead is not disturbed by the accompanying air. The "decompression means mounted on the die head" means that the decompression chamber (also simply referred to as a chamber) is provided outside the die head and near the application bead so that the application bead is not disturbed by entrained air. Means decompression means.
Usually, in the above-mentioned "in the time-dependent change of the film thickness of the coating material applied to the base material over a predetermined short period and a long period," the predetermined short period is at the nsec (nanosecond) level. The long term is at the time level.
Further, the pump as a means for supplying the application material of the application means may be any pump that can change the flow rate by using electricity, pneumatics, etc. of gears, diaphragms, tubes, etc. as power.
[0011]
[Action]
The coating apparatus of the present invention is configured as described above. Specifically, the coating material is applied to a sheet-shaped or web-shaped substrate by a coating unit having a die head having a manifold portion and a slit-shaped discharge port. A coating device that applies to the surface of the coating, and a decompression device consisting of a chamber and a vacuum device is provided near the coating bead to eliminate the steady influence of entrained air, which is one of the disturbance factors on the state of the coating bead. It is an equipment that can respond to sudden fluctuations caused by pasters etc. even if measures such as changing the type of material to be applied or applied material, stabilizing the environment, improving the accuracy of the liquid supply system, etc. Equipment can be provided.
Specifically, one or more state quantity detecting means for detecting a predetermined state quantity correlated with the state of the coating bead, and a predetermined state quantity correlating with the state of the coating bead corresponding to a predetermined control amount. Using one or more state quantity changing means for changing the state of the application bead so as to obtain a reference coating quality using the state quantity data detected from the one or more state quantity detection means. A control unit for calculating a control amount for controlling each of the corresponding predetermined state amount changing means, and sending the control amount to the corresponding predetermined state amount changing means, so that the reference coating quality is obtained. In order to maintain the state of the application bead, in order, detection processing for detecting the state quantity by the state quantity detection means, calculation processing for calculating the control quantity corresponding to the state quantity obtained by the detection processing by the calculation unit, and state quantity change Said by means The state quantity change processing for changing the state quantity by the control amount obtained by the calculation process is repeated in real time a series of processes consisting of, by and performs state quantity control, have achieved this.
As the state quantity to be detected, for example,
(1) For the base material immediately before coating, the distance from the reference surface, the surface roughness, the surface reflectance, the gloss, the tint, or in the case of a transparent material, the light transmission amount, etc.
(2) Immediately after coating, focusing on the coating film thickness, the distance between the reference surface and the coating surface, or a specific component in the coating film, the concentration of the component, the absorption spectrum, etc.
(3) About the application means, the pressure, temperature, viscosity, and density of the application material in each interior, electric signals from a driving device such as a pump, etc.
(4) In order to eliminate the constant influence of the entrained air, if a pressure reducing means comprising a chamber and a vacuum device is used as a coating bead stabilizing means near the coating bead, suction pressure or air is used as detection data. Quantity etc.
These are appropriately used according to the purpose.
Usually, the state quantities that are correlated with the state of the coating bead include the coating film thickness, film thickness deviation, vibration, coating gap, temperature, pressure, physical properties of the coating material, physical properties of the base material, etc. Is used.
As the coating material, those having various viscosities, such as a solution or a paste, can be applied irrespective of an aqueous system or a solvent system.
As the substrate to be applied, a sheet-like or web-like material such as glass, metal, paper, or plastic film can be applied.
[0012]
For example, when the number of state quantity detecting means is n and the number of state quantity changing means is k, the relationship between each part of the coating apparatus according to the first aspect of the present invention, the state quantity, and the control quantity is roughly as shown in FIG. Become.
Here, the operation of the coating apparatus shown in FIG. 1 will be briefly described.
In FIG. 1, thick solid arrows indicate the direction of processing, and S0 to S5 indicate steps of the processing operation.
First, from a coating unit 110 (S0) including a substrate to be coated, which is a system controlled to maintain the state of the coating bead well, a predetermined state amount having a correlation with the state of the coating bead is obtained. The state quantities are detected by the state quantity detection means 1 to n (S1), and the detection data is obtained as it is or further obtained from the detection data to obtain the state quantity 1 to the state quantity m. (S2)
Next, the calculating means 130 calculates each control amount of the state quantity changing means 1 to the state quantity changing means k in order to change the state of the coating bead so that the coating quality becomes the reference coating quality (S3), and is obtained. The control amount 1 to the control amount k (S4) are sent to corresponding state amount changing means.
Next, the state quantity changing means 1 to the state quantity changing means k correspond to the respective control amounts, and are systems controlled to maintain the state of the application bead in good condition. Change the state quantity. (S5)
The state quantity in the application unit 110 including the base material to be applied changes according to each control amount.
Further, such a series of processes (steps S0 to S5) are repeatedly performed in real time.
In this way, the state quantity is controlled, and by appropriately determining the interval between the series of processes (steps S0 to S5), it is possible to cope with sudden instability of the state of the coating bead.
[0013]
Specifically, the coating means has a pump for supplying a constant amount of coating material, a pressure reducing means attached to the die head, and a thickness gauge for measuring the coating film thickness applied to the base material, The amount of change in the thickness of the applied coating film in a predetermined short-term and long-term time-dependent change and the amount of change in the traveling direction (speed unevenness) of the substrate and the direction perpendicular to the substrate (mechanical vibration) The amount of vibration is detected as a state quantity, and using these state quantities, the fluctuation state of the pressure in the coating bead is estimated, and the control amount of the state amount changing means for canceling this pressure fluctuation is calculated. In the case where the control amount obtained by the calculation is given to the state amount changing means for control, the variation in film thickness can be suppressed.
In addition, a pump or a diaphragm is used as the state quantity changing means, and a means for giving a pressure signal to cancel the fluctuation of the pressure in the application bead or a pressure reducing means attached to a die head is used as the state quantity changing means. , Such as giving pressure, such as to cancel the fluctuation of the pressure in the coating bead,
From the data of the state quantity, the amplitude and phase of the vibration due to the disturbance of the substrate to be coated are captured, and, for example, by giving an opposite-phase signal to the pump, it is possible to control the pulsation of the pump and suppress the variation in film thickness. it can.
The calculation process for this is performed by a CPU or the like on the PC.
[0014]
Further, as the state quantity detecting means, pressure gauges for measuring the pressure in the manifold of the coating head of the coating means and the pressure of the pressure reducing means attached to the die head are attached, and the pressure reducing means attached to the die head is continuously connected. In order to eliminate the living and streak defects that occur, as a state quantity changing means, the deviation value of the film thickness continuously generated in the width direction, the pressure value of the pressure reducing means attached to the die head, and the pressure in the manifold Are detected as state quantities Q1, Q2, and Q3, respectively, and the pressure state in the coating bead is estimated using the state quantities Q2 and Q3 so that the state quantity Q1 falls within the reference value. The control amount of the pressure reducing means (of the pump) as a means for eliminating living and streak defects is calculated, and the calculated control amount is reduced by the pressure reducing means (the state amount changing means) If it is intended to control given to the pump),
Alternatively, as the state amount detecting means, a pressure gauge for measuring the pressure in the manifold of the coating head of the coating means and the pressure of the pressure reducing means attached to the die head is attached, and a gap control means capable of adjusting the coating gap amount. The gap control means is used as a state quantity changing means for eliminating a living or streak defect which continuously occurs. , The pressure value in the manifold, the pressure value in the manifold, and the application gap amount as state quantities are detected as state quantities Q1, Q2, Q3, and Q4, respectively, and the state quantity Q1 falls within the reference value. As described above, the state of the pressure in the coating bead is estimated using the state quantities Q2, Q3, and Q4, and the gap and the space control means as the state quantity changing means are used for the living and the stream. In the case where the control amount for eliminating the defect is calculated and the calculated control amount is given to the gap control means for control, it is possible to eliminate the living and streak defects which continuously occur. I have.
[0015]
In addition, as a state quantity detecting means, a pressure gauge is attached to each of a coating head of the coating means, a pump unit for supplying the coating material to the coating head, and a pipe unit, and a film of the coated base material is provided. It is equipped with a film thickness gauge for measuring the thickness, based on the data of the film thickness measured by the film thickness meter, when it is determined that there is a coating drop that is not applied to the substrate surface, A pump for supplying a coating material as a state quantity changing means based on each state quantity of the pressure of the pressure gauge of the coating head, the pressure of the pressure gauge of the pump section, and the pressure of the pressure gauge of the pipe section. Or the control amount of the gap control means as the state amount changing means is calculated, and the pump flow rate of the pump for supplying the coating material as the state amount changing means is increased, or the gap control as the state amount changing means is performed. Substrate by means If it is intended to adjust the distance between the coating head of the coating means, which enables prevention of the occurrence of coating spots is a position not applied to the substrate surface.
When the coating material is water-soluble, a moisture meter can be used as a film thickness meter.
[0016]
Further, as a state quantity detecting means, a viscometer for measuring the viscosity of the coating material is attached to the coating material supply tank, and the viscosity of the coating material in the supply tank is obtained as a state quantity. As a change means, having a temperature control means for controlling the temperature of the coating material in the supply tank, based on viscosity data measured by a viscometer as a state quantity detection means, as a state quantity change means If the temperature control means controls the temperature, which is a parameter of viscosity adjustment, and adjusts the viscosity of the coating material in the supply tank, the viscosity of the coating material in the supply tank is easily adjusted. It is possible.
[0017]
The coating means is not limited to roll coating, curtain coating, slide coating, and die coating. Any means can be used as long as the film thickness can be changed by pre-weighing and the flow rate of a coating material (also referred to simply as a liquid) supply device. Good.
The film thickness meter is not particularly limited as long as the film thickness can be measured with a desired accuracy. However, a film thickness meter that does not impair coating quality by measurement is preferable. As a moisture meter.
A moisture meter measures the amount of water in a coating material after application using infrared rays, etc., and obtains the film thickness by knowing the water content from data on the relationship between the water content and the film thickness obtained in advance. It is.
[0018]
The coating apparatus of the present invention uses a sheet material such as a web such as paper, a resin film, or a metal foil or a sheet-like substrate such as a glass, a metal, or a resin as a material to be coated (also referred to as a substrate). From those of high viscosity to paste-like, regardless of aqueous system, solvent system, and when applied to those containing particles, it is effective if it is possible to detect the applied surface by some means It can respond to sudden disturbances.
Also, the application technical field is not particularly limited.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of a coating apparatus according to the present invention will be described with reference to the drawings.
FIG. 2 is a schematic configuration diagram showing a part of an embodiment of the coating apparatus of the present invention in detail. FIGS. 3A to 3C show coating beads and coating bead stabilization in various coating methods. FIG. 3 is a diagram illustrating an application state near an application head unit for explaining the apparatus.
In FIG. 2, a thick solid arrow indicates the direction of data flow of the state quantity, a thick dotted arrow indicates a control direction, and a thin arrow in FIG. 2 and a thick arrow in FIG. Is shown.
In FIG. 2, 210 is a coating head (die head), 211 is a manifold portion, 212 is a slit-shaped discharge port (also simply referred to as a slit), 221 is a pump, 231 is a transport system controller, 232 is a transport roll, and 241 is a vacuum device. 242 is a chamber, 250 is a state quantity, 251 is a film thickness gauge, 251a is a measurement head, 252 is a laser displacement gauge, 252a is a measurement head, 260 is a calculation unit (also called a calculation control unit or coating control unit), and 270 is The coating material 280 is a base material,
3, reference numeral 11 denotes a coating head, 11a denotes a manifold portion, 11b denotes a slit portion, 12 denotes a substrate, 13 denotes a coating material, 13B denotes a coating bead, 21 denotes a coating head, 21a denotes a manifold portion, 21b denotes a slit portion, and 22 denotes a coating portion. Is a base material, 23 is a coating material, 23B is a coating bead, 25 is a suction chamber, 31 is a coating head, 31a is a manifold portion, 31b is a slit portion, 32 is a base material, 33 is a coating material, and 33B is a coating bead. .
[0020]
One example of an embodiment of the coating of the present invention will be described with reference to FIG.
In this example, as a coating unit for coating a liquid or paste-like coating material 270 on the surface of a base material 280 that moves in one direction, a coating head 210 including a manifold unit 211 and a die head having a slit-shaped discharge port 212, A coating material supply unit including a coating material supply pump 221 and a tank (not shown), a transfer system controller 231, and a base material transfer unit having a transfer roll 232 are provided, and the coating bead is not disturbed by entrained air. A coating device provided with a pressure reducing means including a suction chamber 242 and a vacuum device 241 as means for constantly stabilizing the supply of the coating material 270 to the manifold portion 211 by a pump via a pipe (not shown). 221.
As a first state quantity detecting means, there is provided a film thickness measuring means having a film thickness meter 251 and a measuring head 251a, and as a second state quantity detecting means, a displacement amount detecting means having a measuring head 251a and a laser displacement meter 252 is provided. The first state quantity detecting means measures the change in film thickness of the coating material 270 applied to the base material 280 to obtain data of the film thickness change as a state quantity. The amount of displacement of the substrate before application is detected perpendicular to the direction of travel of the substrate by the state amount detecting means, and this is obtained as a state amount. Further, the change in film thickness detected by the arithmetic unit 260 is obtained. And the displacement data of the base material 280, the amplitude and phase of the vibration due to the disturbance of the base material 280 to be applied are captured, and a pressure signal for canceling the amplitude and phase is supplied. Pump 2 for Calculates the control amount allowed to occur in 1, applied to the pump 221 as the state quantity change means the control amount, intended to suppress the film thickness variation, the series of control is performed by repeating real time.
[0021]
Further, although not shown, the coating apparatus of the present example further has a pressure gauge attached to the manifold 211 of the coating head 210 of the coating means as a third state quantity detecting means, and applies the coating material 270 to the coating head 210. A pressure gauge is also attached to the pump 221 for supplying and a piping section (not shown), and the pressure value of each section is obtained as a state quantity.
Then, based on the data of the film thickness change measured by the film thickness measuring device 251 having the film thickness meter 251 as the first state quantity detecting device and the measuring head 251a, the portion is not applied to the surface of the base material 280. When it is determined that there is coating loss, the pump flow rate is increased if the pump flow rate can be determined to be insufficient by referring to the pressure values of the pressure gauge of the manifold 211 of the coating head 210, the pump 221 and the pressure gauge of the piping section. If it is determined that is sufficient, gap control for optimizing the distance between the base material 180 and the coating head 110 of the coating unit 100 is performed, and this series of controls is repeatedly performed in real time.
In the above description, the flow rate control means for changing the pump flow rate and the gap control means for controlling the gap amount are the state quantity change means when there is an application failure.
[0022]
Further, in the coating apparatus of this example, although not shown, as a fourth state quantity detecting means, a viscosity of the coating material 270 is measured in a supply tank (not shown) of the coating material 270. A viscosity meter (not shown) is attached, and the data of the viscosity change of the coating material 270 in the supply tank is obtained as a state quantity, and the viscosity change measured by the viscometer obtained from the state detecting means is obtained. Based on the above data, the temperature as a parameter of viscosity adjustment is controlled by using a heater (not shown) for heating the supply tank as a state quantity changing means, and the viscosity of the coating material in the supply tank is adjusted. I do.
Of course, this series of control is repeatedly performed in real time.
In the above description, the heater for heating is the state quantity changing means.
[0023]
Further, the coating apparatus of the present example uses the pressure reducing means attached to the die head as a state amount changing means for eliminating a living or streak defect which continuously occurs, and a film thickness amount which continuously occurs. The deviation value in the width direction, the pressure value of the pressure reducing means mounted on the die head, and the pressure value in the manifold are detected as state quantities Q1, Q2, and Q3, respectively, so that the state quantity Q1 falls within the reference value. Then, using the state quantities Q2 and Q3, the pressure state in the coating bead is estimated, and the control amount for eliminating the living and streak failure of the pump of the pressure reducing means as the state quantity changing means is calculated. The control amount obtained as described above is given to a pump of a pressure reducing means as the state quantity changing means for control.
In this example, the pump of the decompression means is used as the state quantity changing means for eliminating the living or streak defect. However, the gap control means is used as the state quantity changing means for eliminating the living or streak defect. You can also.
In this case, for example, the deviation value in the width direction of the film thickness amount continuously generated, the pressure value of the pressure reducing means attached to the die head, the pressure value in the manifold, the state value of the application gap amount, The state quantities Q1, Q2, Q3, and Q4 are detected, respectively, and the pressure state in the coating bead is estimated using the state quantities Q2, Q3, and Q4 so that the state quantity Q1 falls within the reference value, and the state quantity changes. A control amount of the gap control means for eliminating living and streak defects is calculated, and the calculated control amount is given to the gap control means for control.
[0024]
As described above, the coating method applicable to the coating apparatus of the present invention includes a die head similar to the coating apparatus of the embodiment, in which the head portion is enlarged in FIG. 3A. The invention is not limited to the die coat using the application head 110.
The slide coat shown in FIG. 3B and the curtain coat shown in FIG.
In either case, as shown in FIG. 3 (b1), by arranging the suction chamber 25 on the back side of the application of the base material, steady application bead stabilization can be achieved. This alone cannot respond to sudden disturbances.
Regardless of the method, by adopting the configuration as in the present invention, it is possible to provide a coating apparatus that can cope with a sudden disturbance.
[0025]
Further, depending on the state quantity to be controlled, for example, such as the above-described viscosity of the coating material in the tank, control may be performed such that the value of the state quantity simply decreases if the value increases, or increases if the value of the state quantity decreases. However, a set of state quantities corresponding to the coating quality may be prepared in advance, and control may be performed to obtain an appropriate set of state quantities to stabilize the coating bead.
[0026]
【The invention's effect】
The present invention is, as described above, a coating apparatus for coating a coating material on a surface of a sheet-shaped or web-shaped substrate by a coating unit having a die head having a manifold portion and a slit-shaped discharge port. A coating device in which a decompression device consisting of a chamber and a vacuum device is provided in the vicinity of the bead so as to eliminate the steady influence of entrained air which is one of the disturbance factors on the state of the coating bead. It has become possible to provide a coating apparatus that can cope with sudden changes that occur even when measures such as changing the type, stabilizing the environment, and increasing the accuracy of the liquid supply system are taken.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a relationship between each part of an example of a coating apparatus of the present invention, a state quantity, and a control quantity.
FIG. 2 is a schematic configuration diagram showing a part of an example of an embodiment of a coating apparatus of the present invention.
FIGS. 3 (a) to 3 (c) are views showing a coating state near a coating head for explaining a coating bead and a coating bead stabilizing device in various coating methods. 3) is a view in which a suction chamber is further attached in FIG.
[Explanation of symbols]
110 Coating means (including base material to be coated)
120 State quantity detection means
130 arithmetic means
140 State quantity changing means
210 Coating head (die head)
211 Manifold section
211, 212 Slit-shaped discharge port (also simply called slit)
221 pump
231 Transport system controller
232 transport roll
241 Vacuum device
242 chamber
250 state amount
251 film thickness gauge
251a measuring head
252 laser displacement meter
252a measuring head
260 arithmetic unit (also called arithmetic control unit or coating control unit)
270 coating material
280 substrate
11 coating head
11a Manifold section
11b slit part
12 Substrate
13 coating material
13B Application bead
21 coating head
21a Manifold section
21b slit part
22 Substrate
23 coating material
23B coating bead
25 Suction chamber
31 coating head
31 Manifold section
31b slit part
32 base material
33 coating material
33B coating bead

Claims

By coating means having a die head having a manifold portion and the discharge port of the slit-shaped, a coating apparatus for applying a coating material to the surface of the sheet or web of base material, there is a state correlated with the coating bead predetermined and one or more state quantity detecting means for detecting a state quantity of the one or more state quantity changing means for the predetermined state quantity condition that there is a correlation between the coating bead is changed in response to a predetermined control amount, Using the state quantity data detected by the one or more state quantity detecting means, each of the corresponding predetermined state quantity changing means is controlled in order to change the state of the coating bead so as to achieve the reference coating quality. a control amount for calculating, which was an arithmetic unit for sending to a corresponding predetermined state quantity changing means, to maintain the state of the coating bead so that the coating quality as a reference, in turn, the state quantity Inspection Detection processing, the state quantity by the detection processing calculation process for calculating a control amount corresponding to the state quantity obtained by the control amount obtained by the arithmetic processing by the state quantity change means by computing section for detecting a state quantity by means A state quantity control process for repeating in real time a series of processes consisting of a state quantity change process for changing the state amount.

Applicator apparatus according to claim 1, the coating means has a quantitative supply pump coating material, vacuum means mounted in the die head, and a film thickness meter which measures the coating film thickness, which is applied to a substrate the provided, the thickness of the coating material applied to a substrate, the variation with time at a given short and long term, and the film thickness variation, the traveling direction (velocity unevenness) of the substrate and the substrate The amount of vibration in the orthogonal direction (mechanical vibration) is detected as a state quantity, and using these state quantities, the fluctuation state of the pressure in the coating bead is estimated, and a state in which this pressure fluctuation is canceled out The control amount of the amount changing means is calculated, and the control amount obtained by the calculation is given to the state amount changing means for control, and a pump or a diaphragm type or the like is used as the state amount changing means. Gives a pressure signal that counteracts pressure fluctuations. Coating apparatus according to claim Rukoto.

2. The coating apparatus according to claim 1, wherein the coating unit has a pump for supplying a coating material at a constant rate, a pressure reducing unit mounted on a die head, and a film thickness meter for measuring a coating film thickness applied to the substrate. the provided, the thickness of the coating material applied to a substrate, the variation with time at a given short and long term, and the film thickness variation, the traveling direction (velocity unevenness) of the substrate and the substrate The amount of vibration in the orthogonal direction (mechanical vibration) is detected as a state quantity, and using these state quantities, the fluctuation state of the pressure in the coating bead is estimated, and a state in which this pressure fluctuation is canceled out The control amount of the amount changing means is calculated, and the control amount obtained by the calculation is given to the state amount changing means for control. The depressurizing means attached to the die head is used as the state amount changing means. Pressure to counteract pressure fluctuations within Coating and wherein the at.

Applicator apparatus according to any one of claims 2 to 3, as the state quantity detection means, the pressure in the manifold of the coating head of the coating means, the pressure of the pressure reducing means mounted on the die head, measured respectively A pressure gauge is attached, and the decompression means attached to the die head is used as a state quantity changing means for eliminating living and streak defects that occur continuously, and a deviation value in the width direction of the film thickness continuously occurring, The pressure value of the pressure reducing means mounted on the die head and the pressure value in the manifold are detected as state quantities Q1, Q2, Q3, respectively, and the state quantities Q2, Q3 are set so that the state quantity Q1 falls within the reference value. was used to estimate the pressure conditions within the coating bead, the decompression means as the state quantity changing means (pump), and calculates the control amount for eliminating a living room or streak defect, is calculated The resulting controlled variable coating apparatus wherein the a state quantity changing means and controls given to pressure reducing means (pump).

4. The coating apparatus according to claim 2, wherein a pressure in a manifold of a coating head of the coating unit and a pressure of a pressure reducing unit attached to a die head are measured as the state amount detecting unit. 5. A pressure gauge is attached, and a gap control means capable of adjusting an application gap amount is provided, and the gap control means is used as a state quantity changing means for eliminating a living or streak defect which continuously occurs. The width-wise deviation value of the film thickness continuously generated, the pressure value of the pressure reducing means mounted on the die head, the pressure value in the manifold, and the application gap amount as the state amount. , Q3, and Q4, and estimates the pressure state in the application bead using the state quantities Q2, Q3, and Q4 so that the state quantity Q1 falls within the reference value. A control amount of the gap control means for eliminating living and streak defects, and applying the calculated control amount to the gap control means to control the gap control means. .

Applicator apparatus according to any one of claims 2 to 5, as the state quantity detecting means, and the coating head of the coating device, a pump for supplying the coating material to the coating head, to the pipe section , respectively, fitted with a pressure gauge, also those with a film thickness meter for measuring the thickness of the coated substrate, based on the measured film thickness data to at film thickness meter, group If it is determined that there is applied missing a portion which is not applied to the wood surface, the pressure of the pressure gauge of the coating head, the pressure of the pressure gauge in the pump unit, and the pressure of the pressure gauge of the pipe section, even if the state quantities Doo, control of the pump for supplying the coating material as a state quantity changing means, or calculates the control amount of the gap control means as a state quantity changing means, supplying the coating material as a state quantity changing means Increase the pump flow rate of the pump, or Coating and wherein the by the gap control means of the state quantity changing means is for adjusting the distance between the application head substrate and the coating means.

The coating device according to claim 6, wherein the coating material is water-soluble, and the film thickness meter is a moisture meter.

Applicator apparatus according to any one of claims 1 to 7, as the state quantity detecting means, attached to the viscometer to measure the viscosity of the coating material in the supply tank of coating material, supply tank those obtaining viscosity of the coating material as the quantity of state, also, as the quantity of state change means, as it has a temperature control means for controlling the temperature of the coating material in the supply tank, the viscometer as a state quantity detection means Based on the measured viscosity data, the temperature control means as the state quantity changing means controls the temperature, which is a parameter of viscosity adjustment, to adjust the viscosity of the coating material in the supply tank. A coating device characterized by the above-mentioned.