Patent Publication Number: US-11649553-B2

Title: Electrolytic solution generator

Description:
RELATED APPLICATIONS 
     This application is a Divisional of U.S. patent application Ser. No. 16/509,386, filed on Jul. 11, 2019, which claims the benefit of foreign priority of Japanese Patent Application No. 2018-133658, filed on Jul. 13, 2018, and Japanese Patent Application No. 2018-133659, filed on Jul. 13, 2018, the contents of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to an electrolytic solution generator. 
     2. Description of the Related Art 
     A conventional electrolytic solution generator is known, which includes an electrolyzing unit composed of a stack of an anode, a conductive film, and a cathode and in which the electrolyzing unit generates ozone (electrogenerated product) to obtain ozonized water (electrolytic solution) (see, for example, PTL 1). 
     The electrolyzing unit described in PTL 1 has grooves where holes formed on the cathode serving as an electrode communicate with holes formed on the conductive film. By applying a voltage to the electrolyzing unit, water lead into the grooves is electrolyzed to produce ozone. 
     CITATION LIST 
     Patent Literature 
     
         
         PTL 1: Unexamined Japanese Patent Publication No. 2017-176993 
       
    
     SUMMARY 
     According to the above conventional technique, the electrolyzing unit is placed in a housing such that an outer periphery of the electrolyzing unit is in contact with an inner surface of the housing. 
     However, even if the outer periphery of the electrolyzing unit is brought into contact with the inner surface of the housing, a positional shift that occurs during stacking work creates a minute gap between the outer periphery of the electrolyzing unit and the inner surface of the housing. This raises a concern that water may enter the minute gap created along the periphery of the electrolyzing unit to stay in the gap. 
     If water is electrolyzed to produce ozone as water stays along the periphery of the electrolyzing unit, a pH value of water staying along the periphery of the electrolyzing unit rises. In such a case, scales mainly made of a calcium component tend to develop, raising a concern that the scales may pile up in the minute gap. 
     When scales produced by electrolyzation of water pile up in the minute gap formed along the periphery of the electrolyzing unit, the housing and the electrolyzing unit are pressurized by the scales piling up in the minute gap, which may lead to deformation of the housing and the electrolyzing unit. 
     An object of the present disclosure is to provide an electrolytic solution generator that can inhibit pressure application by scales to a housing and an electrolyzing unit. 
     An electrolytic solution generator according to the present disclosure includes an electrolyzing unit having a stacked structure in which a conductive film is interpose between a cathode and an anode, the electrolyzing unit electrolyzing a liquid, and a housing in which the electrolyzing unit is placed. 
     In the housing, a channel is disposed, the channel having an inlet into which a liquid to be supplied to the electrolyzing unit flows and an outlet from which an electrolytic solution generated by the electrolyzing unit flows out and causing a liquid to flow in a liquid-flow direction intersecting a stacking direction of the stacked structure. 
     In the electrolyzing unit, a groove is disposed as a groove which is open to the channel and to which at least a part of an interface between the conductive film and the cathode and an interface between the conductive film and the anode is exposed. 
     A space is disposed between at least either an outer periphery of the cathode or an outer periphery of the anode and an inner surface of the housing. 
     According to the present disclosure, the electrolytic solution generator that can inhibit pressure application by scales to the housing and the electrolyzing unit can be obtained. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is an exploded perspective view of an electrolyzed water generator according to one exemplary embodiment of the present disclosure; 
         FIG.  2    is a sectional view taken by cutting the electrolyzed water generator according to the one exemplary embodiment of the present disclosure along a plane perpendicular to a liquid-flow direction; 
         FIG.  3    is an enlarged sectional view of a part of an electrolyzing unit according to the one exemplary embodiment of the present disclosure, the part having a conductive film-side groove formed therein; 
         FIG.  4    is an enlarged plan view of a part of an anode stacked on a feeder, according to the one exemplary embodiment of the present disclosure; 
         FIG.  5    is an enlarged plan view of a part of a conductive film stacked on the anode, according to the one exemplary embodiment of the present disclosure; 
         FIG.  6    is an enlarged plan view of a part of a cathode stacked on the conductive film, according to the one exemplary embodiment of the present disclosure; 
         FIG.  7    is an enlarged view of a part of an electrolyzed water generator according to a first modification of the present disclosure, showing a sectional view corresponding to the sectional view of  FIG.  3   ; 
         FIG.  8    is an enlarged view of a part of an electrolyzed water generator according to a second modification of the present disclosure, showing a sectional view corresponding to the sectional view of  FIG.  3   ; 
         FIG.  9    is an enlarged view of a part of an electrolyzed water generator according to a third modification of the present disclosure, showing a sectional view corresponding to the sectional view of  FIG.  3   ; 
         FIG.  10    is an enlarged view of a part of an electrolyzed water generator according to a fourth modification of the present disclosure, showing a sectional view corresponding to the sectional view of  FIG.  3   ; 
         FIG.  11    is an enlarged view of a part of an electrolyzed water generator according to a fifth modification, showing a sectional view corresponding to the sectional view of  FIG.  3   ; 
         FIG.  12    is an enlarged view of a part of the electrolyzing unit according to the one exemplary embodiment of the present disclosure, the part having the conductive film-side groove formed therein; 
         FIG.  13    is an enlarged plan view of a part of the conductive film stacked on the anode, according to the one exemplary embodiment of the present disclosure; 
         FIG.  14    is an enlarged plan view of a part of the cathode stacked on the conductive film, according to the one exemplary embodiment of the present disclosure; 
         FIG.  15    depicts the conductive film shifted in position relatively against the cathode in a liquid-flow direction, according to the one exemplary embodiment of the present disclosure, showing a plan view corresponding to the plan view of  FIG.  14   ; and 
         FIG.  16    depicts the conductive film shifted in position relatively against the cathode in a width direction, according to the one exemplary embodiment of the present disclosure, showing a plan view corresponding to the plan view of  FIG.  14   . 
     
    
    
     DETAILED DESCRIPTION 
     Exemplary embodiments of the present disclosure will hereinafter be described with reference to drawings. It should be noted that the following exemplary embodiments do not limit the present disclosure. 
     In the following description, an ozonized water generator that generates ozone (electrogenerated product), causes ozone to dissolve into water (liquid), thereby generates ozonized water (electrolyzed water, i.e., electrolytic solution), will be explained exemplarily as an electrolytic solution generator. 
     Ozonized water, which is effective for sterilization and organic material decomposition, is widely used in fields of water processing, food, and medical practice. Ozonized water has advantages of causing no residual effect and creating no byproduct. 
     In the following description, a direction in which a channel extends is defined as liquid-flow direction X (in which a liquid flows), a widthwise direction of the channel as a width direction Y (which intersects the liquid-flow direction), and a direction in which electrodes and a conductive film are stacked as stacking direction Z (see  FIG.  1   ). 
     In the following exemplary embodiments, a vertical direction of the electrolytic solution generator that is disposed with its electrode case lid located on the upper side represents stacking direction Z. 
     First Exemplary Embodiment 
     As shown in  FIGS.  1  and  2   , ozonized water generator  1  according to an exemplary embodiment includes housing  10 , in which channel  11  is formed (see  FIG.  2   ). 
     Inside housing  10 , where channel  11  is formed, electrolyzing unit  50  is disposed in such a way as to face channel  11 . Water flowing through channel  11  is electrolyzed by electrolyzing unit  50 . According to the present exemplary embodiment, electrolyzing unit  50  is disposed in housing  10  such that upper surface  50   a  of electrolyzing unit  50  (one surface of electrolyzing unit  50  that is on the upper side in stacking direction Z) faces channel  11 , as shown in  FIGS.  2  and  3   . 
     As shown in  FIGS.  1  and  2   , electrolyzing unit  50  has stacked structure  51 . Stacked structure  51  has anode (electrode)  54 , cathode (electrode)  55 , and conductive film  56 , which are stacked such that conductive film  56  is interposed between anode (electrode)  54  and cathode (electrode)  55 , that is, interposed between a plurality of electrodes adjacent to each other. 
     Channel  11  has inlet  111  into which a liquid to be supplied to electrolyzing unit  50  flows, and outlet  112  from which ozonized water generated by electrolyzing unit  50  flows out. Channel  11  is formed in housing  10  such that liquid-flow direction X intersects stacking direction Z of stacked structure  51 . 
     In stacked structure  51 , grooves  52  are formed as grooves which are open to channel  11  and to which at least a part of interfaces  57  and  58  between conductive film  56  and the electrodes (anode  54  and cathode  55 ) is exposed (see  FIG.  3   ). When at least one groove  52  is formed in stacked structure  51 , groove  52  functions effectively. 
     Since grooves  52  are formed in stacked structure  51 , water supplied from inlet  111  to channel  11  can be lead to grooves  52 . Water lead to grooves  52  is subjected to electrolyzing that causes an electrochemical reaction, which creates ozonized water containing ozone as an electrogenerated product. 
     Housing  10  is made of, for example, a non-conductive resin, such as polyphenylene sulfide (PPS). According to the present exemplary embodiment, housing  10  has electrode case  20  and electrode case lid  40 . Electrode case  20  has an opening on its top, and has recession  23  in which electrolyzing unit  50  is placed. Electrode case lid  40  covers the opening of electrode case  20 . 
     As shown in  FIG.  1   , electrode case  20  has bottom wall  21  and peripheral wall  22  formed consecutively on a periphery of bottom wall  21 , thus being formed substantially into a box shape with an open top. In other words, in electrode case  20 , recession  23  is formed as a recession that is demarcated by inner surface  21   a  of bottom wall  21  and inner surface  22   a  of peripheral wall  22  and that has an open top. 
     Electrolyzing unit  50  is inserted from an opening side (upper side) into recession  23  and is therefore placed in recession  23 . The opening of recession  23  is formed to be larger in outline than electrolyzing unit  50  in a view along stacking direction Z. This allows electrolyzing unit  50 , of which the stacking direction matches the vertical direction (stacking direction Z), to be inserted into recession  23  as an original position of electrolyzing unit  50  is maintained. 
     According to the present exemplary embodiment, electrolyzing unit  50  is placed in recession  23  via elastic material  60 . Specifically, electrolyzing unit  50  is placed in recession  23  such that elastic material  60  is interposed between electrolyzing unit  50  and electrode case  20  and that elastic material  60  is in contact with lower surface  50   b  of electrolyzing unit  50 . Elastic material  60  is made of, for example, a material having elasticity, such as rubber, plastic, and metal spring. 
     According to the present exemplary embodiment, when electrode case lid  40  is attached to electrode case  20 , channel  11  is formed between electrolyzing unit  50  and electrode case lid  40 . It is preferable that channel  11  be formed such that sectional areas of its part facing electrolyzing unit  50  (areas of sections of channel  11  that are taken by cutting channel  11  along a plane perpendicular to liquid-flow direction X) are substantially equal at a plurality of locations on channel  11 . 
     Electrode case lid  40  has lid body  41  of a substantially rectangular plate-like shape, and protrusion  42  that protrudes downward from a center of a lower part of lid body  41  and that is inserted in recession  23  of electrode case  20 . 
     On a periphery of protrusion  42  of lid body  41 , fitting recession  411  for welding is formed along the entire periphery. When electrode case lid  40  is attached to electrode case  20 , fitting protrusion  241  for welding, which is formed along the entire periphery of the opening of electrode case  20 , is inserted in fitting recession  411  (see  FIG.  2   ). 
     According to the present exemplary embodiment, flange  24 , which extends outward substantially in the horizontal direction, is formed consecutively on an upper end of peripheral wall  22  of electrode case  20  to extend along the whole of peripheral wall  22 . On flange  24 , fitting protrusion  241 , which protrudes upward, is formed in such a way as to encircle the opening of electrode case  20 . Protrusion  42  is inserted in recession  23  as fitting protrusion  241  is inserted in fitting recession  411 . In this state, electrode case lid  40  and electrode case  20  are welded together. 
     It is possible that electrode case lid  40  is attached to electrode case  20  by screwing electrode case lid  40  onto electrode case  20  as a sealing material is interposed between electrode case lid  40  and electrode case  20 . 
     On both ends and a center in width direction Y of a lower surface of protrusion  42 , protrusions  421  are formed, respectively, protrusions  421  pushing electrolyzing unit  50  downward. When electrolyzing unit  50  is placed in recession  23  via elastic material  60  and electrode case lid  40  is attached to electrode case  20 , protrusions  421  formed on electrode case lid  40  pushes electrolyzing unit  50  downward. 
     In this manner, according to this exemplary embodiment, when electrolyzing unit  50  is pushed downward, fixed pressure is applied by elastic material  60  to the whole of electrolyzing unit  50 . This enhances a state of adherence of components making up electrolyzing unit  50 . 
     According to the present exemplary embodiment, elastic material  60  has a plurality of through-holes  61  penetrating elastic material  60  in stacking direction Z and being lined up in the lengthwise direction (liquid-flow direction X). Because of this structure, when pushed down by electrolyzing unit  50 , elastic material  60  is allowed to deform toward through-holes  61 . In this manner, allowing elastic material  60  to deform toward through-holes  61  inhibits elastic material  60  pushed down by electrolyzing unit  50  from putting pressure on electrode case  20 . 
     According to the present exemplary embodiment, grooves  412  are formed on an upper surface of lid body  41 . These grooves  412  are used to position ozonized water generator  1  or prevent it from being caught by other components or being inserted in an inverted position when ozonized water generator  1  is fixed. By providing ozonized water generator  1  with grooves  412 , ozonized water generator  1  can be incorporated in an apparatus requiring an ozone generation function more easily without an error. 
     Ozonized water generator  1  is incorporated in a different apparatus or equipment and is used in such a state. It is preferable that when ozonized water generator  1  is incorporated in a different apparatus or equipment, ozonized water generator  1  be set in a standing position in which inlet  111  is located on the lower side while outlet  112  is located on the upper side. If ozonized water generator  1  is set with its inlet  111  located on the lower side and outlet  112  located on the upper side, ozone generated at electrode interfaces can be separated quickly by buoyancy, from the electrode interfaces. In other words, ozone generated at the electrode interfaces can be separated quickly from the electrode interfaces before ozone grow into bubbles of ozone. As a result, ozone tends to dissolve into water swiftly, which improves ozonized water generation efficiency. The setting position of ozonized water generator  1  is not limited to the above position, and ozonized water generator  1  may be set properly in other positions. 
     A specific configuration of electrolyzing unit  50  will then be described. 
     Electrolyzing unit  50  is of a substantially rectangular shape of which the lengthwise direction matches liquid-flow direction X in a plan view (view in stacking direction Z). Electrolyzing unit  50  has stacked structure  51  formed by stacking anode  54 , conductive film  56 , and cathode  55  in increasing order. In this manner, according to this exemplary embodiment, stacked structure  51  is formed such that conductive film  56  is interposed between anode  54  and cathode  55  that are the electrodes adjacent to each other. 
     Under anode  54 , feeder  53  is disposed. Via this feeder  53 , electricity is supplied to anode  54 . 
     According to the present exemplary embodiment, in a plan view, each of feeder  53 , anode  54 , conductive film  56 , and cathode  55  is of a tabular shape having a rectangular plane, of which a lengthwise direction matches liquid-flow direction X and a widthwise direction matches width direction Y, and having a thickness in stacking direction Z. At least either anode  54  or cathode  55  may be of a film-like, meshed, or linear form. 
     Feeder  53  may be made of, for example, titanium. Feeder  53  is in contact with a side of anode  54  that is opposite to a side of anode  54  that is in contact with conductive film  56 . To one end in the lengthwise direction of feeder  53  (upstream side in liquid-flow direction X), feeder shaft  53   b  for anode is electrically connected via spiral spring  53   a . Feeder shaft  53   b  is inserted in though-hole  211  formed on one end in liquid-flow direction X of bottom wall  21 . A part of feeder shaft  53   b  that projects out of electrode case  20  is electrically connected to a positive electrode of a power supply unit (not depicted). 
     Anode  54  is formed by, for example, coating a conductive substrate, which is made of silicon and is about 10 mm in width and 100 mm in length, with a conductive diamond film. In another case, for example, a pair of conductive substrates each of which is about 10 mm in width and 50 mm in length may be used together to form anode  54 . The conductive diamond film has boron-doped conductivity. The conductive diamond film of about 3 μm in thickness is deposited on the conductive substrate by plasma chemical vapor deposition (plasma CVD). 
     Conductive film  56  is disposed on anode  54  having the conductive diamond film deposited on the conductive substrate. Conductive film  56  is a proton-conducting ion-exchange film, having a thickness ranging from 100 μm to 200 μm. Conductive film  56  has a plurality of conductive film-side holes (conductive film-side grooves)  56   c  penetrating conductive film  56  in its thickness direction (stacking direction Z) (see  FIG.  5   ). 
     According to the present exemplary embodiment, each of conductive film-side holes  56   c  is substantially the same in shape. Specifically, each of conductive film-side holes  56   c  is an elongated hole that is long and narrow in width direction Y. Conductive film-side holes  56   c  are lined up at a given pitch along the lengthwise direction (liquid-flow direction X). Conductive film-side holes  56   c  may be of a shape and in arrangement that are different from the shape and arrangement shown in  FIG.  5   . When at least one conductive film-side hole  56   c  is formed, conductive film-side hole  56   c  functions effectively. 
     Cathode  55  is disposed on conductive film  56 . Cathode  55  is provided as, for example, a titanium electrode plate of about 0.5 mm in thickness. To the other end in the lengthwise direction of cathode  55  (downstream side in liquid-flow direction X), feeder shaft  55   b  for cathode is electrically connected via spiral spring  55   a . Feeder shaft  55   b  is inserted in though-hole  211  formed on the other end in in liquid-flow direction X of bottom wall  21 . A part of feeder shaft  55   b  that projects out of electrode case  20  is electrically connected to a negative electrode of the power supply unit (not depicted). 
     Cathode  55  has a plurality of cathode-side holes (cathode-side grooves, i.e., electrode-side grooves)  55   e  penetrating cathode  55  in its thickness direction (see  FIG.  6   ). According to this exemplary embodiment, each of cathode-side holes  55   e  is substantially the same in shape. Specifically, in a plan view, each cathode-side hole  55   e  is of a V shape in which a bent portion  55   f  is located on the downstream side. 
     Cathode-side holes  55   e  are lined up at a given pitch along the lengthwise direction (liquid-flow direction X). 
     The pitch of cathode-side holes  55   e  may be equal to the pitch of conductive film-side holes  56   c  or may be different from the same. Cathode-side holes  55   e  may be of a shape and in arrangement that are different from the shape and arrangement shown in  FIG.  6   . When at least one cathode-side hole  55   e  is formed, cathode-side hole  55   e  functions effectively. 
     In this manner, according to the present exemplary embodiment, conductive film-side holes  56   c  and cathode-side holes  55   e  are different in shape (at least in outline or size) from each other in a plan view (view along the stacking direction of stacked structure  51 ). In this structure, even if conductive film  56  is shifted against cathode (electrode)  55  relatively in a direction intersecting stacking direction Z, a change in a contact area between conductive film  56  and cathode (electrode)  55  can be suppressed. It is possible to make conductive film-side holes  56   c  and cathode-side holes  55   e  equal in shape (in outline and size) with each other in a plan view. 
     It is necessary that when conductive film  56  and cathode  55  are stacked, at least some of their holes (conductive film-side holes  56   c  and cathode-side holes  55   e ) communicate with each other and a sufficient electrical contact area between them be secured. If conductive film  56  and cathode  55  meet the above condition, they may be equal or different in projection dimensions (size in a plan view) with each other or from each other. 
     According to the present exemplary embodiment, cathode  55  is larger in width in width direction Y than conductive film  56  (see  FIG.  3   ). 
     Projection dimensions of anode  54  may be equal to projection dimensions of at least either conductive film  56  or cathode  55  or may be different from the same. It is nevertheless preferable that anode  54  have a size that allows it to cover conductive film-side holes  56   c  from below when anode  54  is stacked. 
     According to the present exemplary embodiment, anode  54  and conductive film  56  are substantially equal in projection dimensions with each other. 
     It is preferable that feeder  53  be capable of supplying electricity efficiently to anode  54  and that elastic material  60  have projection dimensions that subject elastic material  60  to pressurization by the whole of a lower surface of feeder  53  (lower surface  50   b  of electrolyzing unit  50 ). 
     According to the present exemplary embodiment, a dimension of feeder  53  in width direction Y is made smaller than that of anode  54  and of conductive film  56 , while a dimension of elastic material  60  in width direction Y is made substantially equal to that of anode  54  and of conductive film  56 . Projection dimensions of feeder  53  and elastic material  60  may be determined to be various dimensions. 
     Electrolyzing unit  50  configured in this manner can be placed in recession  23  of electrode case  20 , for example, by the following method. 
     First, feeder  53  is disposed on elastic material  60  inserted in recession  23  of electrode case  20 . Specifically, feeder  53  with feeder shaft  53   b  having its front end directed downward is put in recession  23  of electrode case  20 . Then, feeder shaft  53   b  is inserted into one through-hole  211  to stack feeder  53  on elastic material  60 . 
     Subsequently, anode  54  is put in recession  23  of electrode case  20  to stack anode  54  on feeder  53 . 
     Subsequently, conductive film  56  is put in recession  23  of electrode case  20  to stack conductive film  56  on anode  54 . 
     Subsequently, cathode  55  with feeder shaft  55   b  having its front end directed downward is put in recession  23  of electrode case  20  as feeder shaft  55   b  is inserted into the other through-hole  211 . Cathode  55  is thus stacked on conductive film  56 . 
     Subsequently, the part of feeder shaft  53   b  for anode, the part projecting out of electrode case  20 , and the part of feeder shaft  55   b  for cathode, the part projecting out of electrode case  20 , are inserted into O-rings  31 , washers  32 , wavy washers  33 , and hexagon nuts  34 , respectively. 
     By tightening hexagon nuts  34 , electrolyzing unit  50  is placed and fixed in recession  23  in a state in which electrolyzing unit  50  is pushed against elastic material  60 . 
     According to the present exemplary embodiment, electrode case lid  40  is moved relatively toward electrode case  20  in stacking direction Z. As a result, protrusion  42  is inserted in recession  23  as fitting protrusions  241  are inserted in fitting recessions  411  for welding. 
     In this manner, ozonized water generator  1  according to the present exemplary embodiment can be assembled by merely moving each component relatively toward electrode case  20  in the vertical direction (stacking direction Z). 
     Operations and effects of ozonized water generator  1  will then be described. 
     To supply ozonized water generator  1  with water, water is fed through inlet  111  into channel  11 . Part of water fed to channel  11  flows into grooves  52  and comes in contact with interfaces  57  and  58  of grooves  52 . 
     In this state (state in which electrolyzing unit  50  is immersed in supplied water), the power supply unit (not depicted) applies a voltage across anode  54  and cathode  55  of electrolyzing unit  50 . This creates a potential difference between anode  54  and cathode  55  via conductive film  56 . The potential difference created between anode  54  and cathode  55  generates a current flowing through anode  54 , conductive film  56 , and cathode  55 . As a result, an electrolyzing process takes place mainly in water in grooves  52 , leading to creation of ozone near interface  57  between conductive film  56  and anode  54 . 
     Ozone created near interface  57  between conductive film  56  and anode  54  is carried by waterflow toward the downstream side of channel  11 , during which ozone dissolves into water. Ozone is caused to dissolves into water in this manner. Hence dissolved ozonized water (ozonized water, i.e., electrolytic solution) is generated. 
     Ozonized water generator  1  can be applied to electrical equipment that uses an electrolytic solution generated by an electrolytic solution generator and to liquid reformer or the like equipped with an electrolytic solution generator. 
     Such electrical equipment and liquid reformers include water processing equipment, such as water purifiers, washing machines, dish washers, washlets, refrigerators, water heaters/servers, sterilizers, medical instruments, air conditioners, and kitchen utensils. 
     According to the present exemplary embodiment, pressure application to peripheral wall  22  (housing  10 ) and electrolyzing unit  50  by scales produced by water electrolyzation is inhibited. 
     Specifically, space S is formed between an outer periphery of at least either cathode  55  or anode  54  and inner surface  22   a  of peripheral wall  22  (inner surface of housing  10 ), and this space S inhibits water from staying on a periphery of electrolyzing unit  50 . 
     By forming space S for letting water flow between the periphery of electrolyzing unit  50  and peripheral wall  22  (inner surface of housing  10 ), water stagnation on the periphery of electrolyzing unit  50  is inhibited. Space S has a gap larger than a manufacturing tolerance that arises when ozonized water generator  1  is assembled. 
     According to the present exemplary embodiment, as described above, cathode  55  is larger in width in width direction Y than conductive film  56 . Anode  54  and conductive film  56  are substantially equal in projection dimensions with each other. 
     When stacked structure  51  is formed, both ends in width direction Y of cathode  55  protrude to be further outside than those of anode  54  and conductive film  56 . 
     In other words, outer periphery (side face)  55   c  of cathode  55  protrudes to be further outside in width direction Y (direction intersecting stacking direction Z) than outer periphery (side face)  54   a  of anode  54 . A part of cathode  55  that protrudes to be further outside in width direction Y than outer periphery  54   a  of anode  54  is defined as cathode-side protrusion  55   g  (see  FIG.  3   ). In this manner, if cathode-side protrusion  55   g , which protrudes to be further outside than respective ends of anode  54  and conductive film  56 , are formed on both ends in width direction Y of cathode  55 , space S is formed between inner surface  22   a  of peripheral wall  22  and anode  54  when stacked structure  51  is placed in recession  23 . Space S is formed also in an area below cathode-side protrusion  55   g  of cathode  55  (area closer to anode  54  in stacking direction Z). 
     According to the present exemplary embodiment, space S has anode-side space (second space) S 2  formed between outer periphery (side face)  54   a  of anode  54  and inner surface  22   a  of peripheral wall  22  (inner surface of housing  10 ). Space S has also lower-side space (third space) S 3  formed in an area closer to anode  54  than to cathode  55  in stacking direction Z. 
     According to the present exemplary embodiment, in a state in which cathode-side protrusion  55   g  is formed, a gap larger than the manufacturing tolerance is formed also between outer periphery (side face)  55   c  of cathode  55  and inner surface  22   a  of peripheral wall  22  (inner surface of housing  10 ). In other words, space S has cathode-side space (first space)  51  formed between outer periphery (side face)  55   c  of cathode  55  and inner surface  22   a  of peripheral wall  22  (inner surface of housing  10 ). 
     In this manner, according to the present exemplary embodiment, space S having cathode-side space (first space)  51 , anode-side space (second space) S 2 , and lower-side space (third space) S 3  is formed between outer periphery (side face)  51   a  of stacked structure  51  and inner surface  22   a  of peripheral wall  22 . 
     According to the present exemplary embodiment, space S is formed at least on the periphery in the lengthwise direction of stacked structure  51 . In other words, at least a part of cathode-side space (first space) S 1  is formed along side faces  51   a . Side faces  51   a  are on both sides in width direction Y of stacked structure  51 , respectively, and extend in the lengthwise direction (liquid-flow direction X). 
     It is preferable that cathode-side space (first space) S 1  communicate with inlet  111  and with outlet  112  and cause water lead to cathode-side space (first space) S 1  to efficiently flow out of outlet  112 . However, cathode-side space (first space) S 1  may communicate with channel  11  at its midpoint. 
     Forming such space S inhibits scales made of a calcium component or the like, the scales being produced by water electrolyzation, from piling up between stacked structure  51  and peripheral wall  22 . 
     For example, vicinity of interface  58  between conductive film  56  and cathode  55  is an area where a pH value tends to rise and therefore scales tend to develop. However, forming space S described in the present exemplary embodiment creates a relatively large space near interface  58 . Specifically, an outer part of interface  58  in width direction Y is exposed to space S in a state in which a space of a give size (lower-side space, i.e., third space S 3 ) is formed in an area (lower side) closer to anode  54  in stacking direction Z and a space of a given size (anode-side space, i.e., second space S 2 ) is formed outside anode  54  in width direction Y. 
     According to the present exemplary embodiment, the outer part of interface  58  in width direction Y is exposed to space S along the lengthwise direction (liquid-flow direction X), which means that almost the entire outer part of interface  58  in width direction Y is exposed to space S. 
     As a result, water lead into space S flows downstream along the liquid-flow direction X. This means that water lead to the vicinity of interface  58  exposed to space S also flows downstream relatively quickly along the liquid-flow direction X. This waterflow, therefore, carries scales produced near interface  58  away to the downstream side before scales stick to stacked structure  51  and housing  10 . In this manner, forming space S described in the present exemplary embodiment inhibits water from staying near interface  58 , where scales tend to be produced, and allows water to carry scales produced near interface  58  away quickly to the downstream side. This inhibits piling of scales between stacked structure  51  and peripheral wall  22 . Hence pressure application by scales to peripheral wall  22  (housing  10 ) and electrolyzing unit  50  is inhibited. 
     It should be noted, however, that although forming space S inhibits piling of scales between stacked structure  51  and peripheral wall  22 , a relatively small amount of scales stick to stacked structure  51  and peripheral wall  22 , nevertheless. When ozonized water generator  1  is used for a long period, therefore, scales sticking to stacked structure  51  and peripheral wall  22  may grow bigger and put pressure onto peripheral wall  22  (housing  10 ) and electrolyzing unit  50 . It is preferable for this reason that space S be given a size large enough to an extent that even when ozonized water generator  1  is used in a period longer than its service life by an ordinary use method, sticking scales do not block up space S. The ordinary use method is determined based on, for example, quality of water (quality of a liquid) supplied into the housing, an average flow velocity/flow rate of water flowing through the housing, ozone generation efficiency (voltage applied across the electrodes and an electrolyzation area), and an estimated service frequency. 
     On the interior of peripheral wall  22  of electrode case  20 , a plurality of positioning protrusions  221  extending in the vertical direction (stacking direction Z) are formed along the lengthwise direction (liquid-flow direction X) (see  FIG.  4   ). These positioning protrusions  221  inhibit a positional shift of anode  54  when anode  54  is stacked (see  FIG.  4   ). According to the present exemplary embodiment, positioning protrusions  221  are formed on a part of the inner surface of peripheral wall  22  (inner surface of the housing), the part being counter to outer periphery  51   a  of stacked structure  51 . Positioning protrusions  221  are equivalent to housing protrusions protruding toward stacked structure  51 . 
     As a result of formation of positioning protrusions (housing protrusions)  221  on peripheral wall  22 , when stacked structure  51  is just placed in recession  23 , space S is formed between outer periphery (side face)  51   a  of stacked structure  51  and inner surface  22   a  of peripheral wall  22 . 
     According to the present exemplary embodiment, conductive film-side recessions  56   b , which serve as relief portions, are formed on outer periphery (side face)  56   a  of conductive film  56  (outline of conductive film  56  in a plan view) (see  FIG.  5   ). Conductive film-side recessions  56   b  are formed on part of conductive film  56  that correspond to positioning protrusions (housing protrusions)  221  when stacked structure  51  is placed in recession  23 . 
     When conductive film  56  is put in recession  23  and is stacked on anode  54 , therefore, conductive film-side recessions  56   b  are set counter to positioning protrusions  221  of peripheral wall  22  (see  FIG.  5   ). Because of this structure, when ozonized water is generated, conductive film  56  having swollen due to its absorption of water is inhibited from interfering with positioning protrusions  221 . 
     Cathode-side recessions  55   d , which serve as relief portions, are formed on outer periphery (side face)  55   c  of cathode  55  (outline in a plan view), which is larger in width in width direction Y than conductive film  56  (see  FIG.  6   ). Cathode-side recessions  55   d  are formed on part of cathode  55  that correspond to positioning protrusions (housing protrusions)  221  when stacked structure  51  is placed in recession  23 . 
     When cathode  55  is put in recession  23  and is stacked on conductive film  56 , therefore, cathode-side recessions  55   d  are set counter to positioning protrusions  221  of peripheral wall  22  (see  FIG.  6   ). Because of this structure, cathode  55 , which is larger in dimension in width direction Y, is inhibited from interfering with positioning protrusions  221 . In other words, cathode-side recessions  55   d  are formed so that interference between cathode  55  and positioning protrusions  221  is inhibited as a surface area of cathode  55  is made larger as much as possible. 
     Space S is effective if it is formed between the outer periphery of at least either cathode  55  or anode  54  and inner surface  22   a  of peripheral wall  22  (inner surface of housing  10 ). For example, stacked structure  51  may have configurations shown in  FIGS.  7  to  11   . 
     Modifications of space S according to the present exemplary embodiment will hereinafter be described. 
       FIG.  7    depicts stacked structure  51  in which outer periphery (side face)  56   a  of conductive film  56  protrude to be further outside in width direction Y (direction intersecting stacking direction Z) than outer periphery (side face)  54   a  of anode  54 . A part of conductive film  56  that protrude to be further outside in width direction Y than outer periphery (side face)  54   a  of anode  54  is defined as conductive film-side protrusion  56   d.    
     In  FIG.  7   , cathode  55  and conductive film  56  are substantially equal in projection dimensions with each other. 
     In this manner, in  FIG.  7   , cathode-side protrusion  55   g  protruding to be further outside than the outer periphery of anode  54  is formed on both sides in width direction Y of cathode  55  as conductive film-side protrusion  56   d  protruding to be further outside than the outer periphery of anode  54  is formed on both sides in width direction Y of conductive film  56 . As a result, when stacked structure  51  is placed in recession  23 , space S having cathode-side space (first space) S 1 , anode-side space (second space) S 2 , and lower-side space (third space) S 3  is formed between outer periphery (side face)  51   a  of stacked structure  51  and inner surface  22   a  of peripheral wall  22 . 
     This configuration also inhibits piling of scales between stacked structure  51  and peripheral wall  22 . 
     As a result of expanding conductive film  56  to both ends in width direction Y of cathode  55 , conductive film  56  comes in contact also with lower surfaces of cathode-side protrusions  55   g . This allows more effective use of an increased area of cathode  55 . This means that the contact area (electrolyzation area) between cathode  55  and conductive film  56  is further increased. 
       FIG.  8    depicts stacked structure  51  in which cathode-side protrusion  55   g , which protrudes to be further outside than respective outer peripheries of anode  54  and conductive film  56 , is formed on both sides in width direction Y of cathode  55  in the same manner as in stacked structure  51  described in the present exemplary embodiment. 
     Outer periphery (side face extending along the lengthwise direction)  55   c  of cathode  55  is in contact with inner surface  22   a  of peripheral wall  22 , and space S is formed between outer periphery  54   a  of anode  54 , outer periphery  56   a  of conductive film  56  and inner surface  22   a  of peripheral wall  22 . In other words, when stacked structure  51  is placed in recession  23 , space S having anode-side space (second space) S 2  and lower-side space (third space) S 3  is formed between outer periphery (side face)  51   a  of stacked structure  51  and inner surface  22   a  of peripheral wall  22 . 
     This configuration also inhibits piling of scales between stacked structure  51  and peripheral wall  22 . 
     In the configuration shown in  FIG.  8    (configuration in which outer periphery  55   c  of cathode  55  is brought into contact with inner surface  22   a  of peripheral wall  22 ), conductive film-side protrusion  56   d  shown in  FIG.  7    can be formed on conductive film  56 . Bring conductive film-side protrusion  56   d  into contact with inner surface  22   a  of peripheral wall  22 , however, raises a concern that water may stay in the area between interface  58  and inner surface  22   a  of peripheral wall  22 , where scales tend to develop. It is preferable for this reason that when conductive film-side protrusion  56   d  is formed, a gap with an adequate size for inhibiting water stagnation (space  5 ) be formed between outer periphery  56   a  of conductive film  56  and inner surface  22   a  of peripheral wall  22 . 
       FIG.  9    depicts stacked structure  51  in which at least a part of outer periphery  54   a  of anode  54  that extends in the lengthwise direction, a part of outer periphery  55   c  of cathode  55  that extends in the lengthwise direction, and a part of outer periphery  56   a  of conductive film  56  that extends in the lengthwise direction are substantially flush with each other. Space S is formed between side face  54   a  of anode  54  that extends lengthwise, side face  55   c  of cathode  55  that extends lengthwise, side face  56   a  of conductive film  56  that extends lengthwise and inner surface  22   a  of peripheral wall  22 . In other words, when stacked structure  51  is placed in recession  23 , space S having cathode-side space (first space)  51  and anode-side space (second space) S 2  is formed between outer periphery (side face)  51   a  of stacked structure  51  and inner surface  22   a  of peripheral wall  22 . 
     This configuration also inhibits piling of scales between stacked structure  51  and peripheral wall  22 . 
       FIG.  10    depicts stacked structure  51  in which the size in width direction Y of anode  54  is made large than that of conductive film  56 , and cathode  55  and conductive film  56  are made substantially equal in projection dimensions with each other. 
     When this stacked structure  51  is formed, both ends in width direction Y of anode  54  are protruded to be further outside than both ends of cathode  55  and of conductive film  56 , and a part of anode  54  that protrudes to be further outside in width direction Y than outer periphery  55   c  of cathode  55  is defined as anode-side protrusion  54   b.    
     In this manner, if anode-side protrusion  54   b , which protrudes to be further outside than the outer periphery of cathode  55  and of conductive film  56 , is formed on both ends in width direction Y of anode  54 , space S is formed between inner surface  22   a  of peripheral wall  22  and cathode  55  when stacked structure  51  is placed in recession  23 . Space S is formed also in an area above anode-side protrusion  54   b  of anode  54  (area closer to cathode  55  in stacking direction Z). 
     In this manner, in  FIG.  10   , space S has cathode-side space (first space)  51  formed between outer periphery (side face)  55   c  of cathode  55  and inner surface  22   a  of peripheral wall  22  (inner surface of housing  10 ). Space S has also upper-side space (fourth space) S 4  formed in an area closer to cathode  55  than to anode  54  in stacking direction Z. 
     In  FIG.  10   , in a state in which anode-side protrusion  54   b  is formed, a gap larger than the manufacturing tolerance is formed also between outer periphery (side face)  54   a  of anode  54  and inner surface  22   a  of peripheral wall  22  (inner surface of housing  10 ). In other words, space S has anode-side space (second space) S 2  formed between outer periphery (side face)  54   a  of anode  54  and inner surface  22   a  of peripheral wall  22  (inner surface of housing  10 ). 
     In this manner, in  FIG.  10   , space S having cathode-side space (first space) S 1 , anode-side space (second space) S 2 , and upper-side space (fourth space) S 4  is formed between outer periphery (side face)  51   a  of stacked structure  51  and inner surface  22   a  of peripheral wall  22 . 
     This configuration also inhibits piling of scales between stacked structure  51  and peripheral wall  22 . 
     In the configuration shown in  FIG.  10   , conductive film-side protrusion  56   d  depicted in  FIG.  7    can be formed on conductive film  56 . Specifically, conductive film-side protrusion  56   d  protruding to be further outside than the outer periphery of cathode  55  can be formed on both sides in width direction Y of conductive film  56  as anode-side protrusion  54   b  protruding to be further outside than the outer periphery of cathode  55  is formed on both sides in width direction Y of anode  54 . 
     This configuration also inhibits piling of scales between stacked structure  51  and peripheral wall  22 . 
     As a result of expanding conductive film  56  to both ends in width direction Y of anode  54 , conductive film  56  comes in contact also with upper surfaces of anode-side protrusions  54   b . This allows more effective use of an increased area of anode  54 . This means that the contact area (electrolyzation area) between anode  54  and conductive film  56  is further increased. 
       FIG.  11    depicts stacked structure  51  in which anode-side protrusion  54   b , which protrudes to be further outside than the outer periphery of cathode  55  and of conductive film  56 , is formed on both sides in width direction Y of anode  54  in the same manner as in stacked structure  51  depicted in  FIG.  10   . 
     Outer periphery (side face extending along the lengthwise direction)  54   a  of anode  54  is in contact with inner surface  22   a  of peripheral wall  22 , and space S is formed between outer periphery  55   c  of cathode  55 , outer periphery  56   a  of conductive film  56  and inner surface  22   a  of peripheral wall  22 . In other words, when stacked structure  51  is placed in recession  23 , space S having cathode-side space (first space) S 1  and upper-side space (fourth space) S 4  is formed between outer periphery (side face)  51   a  of stacked structure  51  and inner surface  22   a  of peripheral wall  22 . 
     This configuration also inhibits piling of scales between stacked structure  51  and peripheral wall  22 . 
     In the configuration shown in  FIG.  11    (configuration in which outer periphery  54   a  of anode  54  is brought into contact with inner surface  22   a  of peripheral wall  22 ), conductive film-side protrusion  56   d  shown in  FIG.  7    can be formed on conductive film  56 . Bring conductive film-side protrusion  56   d  into contact with inner surface  22   a  of peripheral wall  22 , however, raises a concern that water may stay in the area between interface  58  and inner surface  22   a  of peripheral wall  22 , where scales tend to develop. It is preferable for this reason that when conductive film-side protrusion  56   d  is formed, a gap with an adequate size for inhibiting water stagnation (space  5 ) be formed between outer periphery  56   a  of conductive film  56  and inner surface  22   a  of peripheral wall  22 . 
     As described above, ozonized water generator (electrolytic solution generator)  1  according to the present exemplary embodiment includes electrolyzing unit  50  that has a stacked structure  51 , in which conductive film  56  is interposed between anode  54  and cathode  55  (between the electrodes adjacent to each other), and that electrolyzes water (liquid). Ozonized water generator  1  includes also housing  10  housing electrolyzing unit  50  therein. 
     In housing  10 , channel  11  is formed, channel  11  having inlet  111  into which water to be supplied to electrolyzing unit  50  flows and outlet  112  from which ozonized water (electrolyzed water, i.e., electrolytic solution) generated by electrolyzing unit  50  flows out and causing water to flow in liquid-flow direction X intersecting stacking direction Z of stacked structure  51 . 
     In electrolyzing unit  50 , grooves  52  are formed as grooves which are open to channel  11  and to which at least a part of interface  57  between conductive film  56  and one electrode (anode  54 ) and interface  58  between conductive film  56  and the other electrode (cathode  55 ) is exposed. 
     According to the present exemplary embodiment, the electrodes adjacent to each other are cathode  55  and anode  54 , and space S that inhibits water stagnation is formed between the outer periphery of either cathode  55  or anode  54  and inner surface  22   a  of peripheral wall  22  (inner surface of the housing). 
     Space S may have cathode-side space (first space)  51  formed between outer periphery (side face)  55   c  of cathode  55  and inner surface  22   a  of peripheral wall  22  (inner surface of the housing). 
     Space S may have anode-side space (second space) S 2  formed between outer periphery  54   a  of anode  54  and inner surface  22   a  of peripheral wall  22  (inner surface of the housing). 
     Space S may have lower-side space (third space) S 3  formed in the area closer to anode  54  than to cathode  55  in stacking direction Z. 
     Forming such space S on the periphery of electrolyzing unit  50  inhibits water from staying on the periphery of electrolyzing unit  50 . Inhibiting water from staying on the periphery of electrolyzing unit  50  inhibits sticking of scales to the periphery of electrolyzing unit  50  and to peripheral wall  22  (housing  10 ). 
     Even if scales stick to the periphery of electrolyzing unit  50  and to peripheral wall  22 , space S formed between electrolyzing unit  50  and peripheral wall  22  suppresses pressure application by scales to electrolyzing unit  50  and peripheral wall  22 , thereby suppresses deformation (warping or the like) of electrolyzing unit  50 . Suppressing the deformation of electrolyzing unit  50  prevents a case where contact between anode  54  and conductive film  56  and between conductive film  56  and cathode  55  becomes irregular. In other words, anode  54  and conductive film  56  are brought into more uniform contact with each other and conductive film  56  and cathode  55  are also brought into more uniform contact with each other as well. 
     In this manner, forming space S between electrolyzing unit  50  and peripheral wall  22  suppresses the deformation of electrolyzing unit  50  caused by scales sticking thereto, thereby makes contact between the conductive film and electrodes of stacked structure  51  more uniform in electrolyzing unit  50 . By making contact between the conductive film and electrodes of stacked structure  51  more uniform, a current-carrying area (e.g., electrolyzation area between conductive film  56  and cathode  55 ) can be secured more stably. Securing the current-carrying area more stably makes a density of current flow in electrolyzing unit  50  more uniform, thereby achieves more stable ozone (electrogenerated product) generation efficiency. 
     In this manner, according to the present exemplary embodiment, ozonized water generator  1  that can inhibit pressure application by scales to peripheral wall  22  (housing  10 ) and electrolyzing unit  50  can be obtained. 
     Outer periphery  55   c  of cathode  55  may be protruded to be further outside in width direction Y (direction intersecting stacking direction Z) than outer periphery  54   a  of anode  54 . 
     This increases the area of cathode  55  by a protruded portion in width direction Y located further outside than outer periphery  54   a  of anode  54 . As a result, the density of current flow in cathode  55  drops, which inhibits piling of scales, which are produced by electrolyzing, on the periphery of cathode  55 . 
     Outer periphery  56   a  of conductive film  56  may be protruded to be further outside in width direction Y (direction intersecting stacking direction Z) than outer periphery  54   a  of anode  54 . 
     In this structure, pressure application by scales to electrolyzing unit  50  and peripheral wall  22  is inhibited, and therefore more stable ozone (electrogenerated product) generation efficiency is achieved. 
     When cathode  55  and conductive film  56  are made larger in size in width direction Y than anode  54 , conductive film  56  comes in contact also with the lower surfaces of both end sides in width direction Y of cathode  55 . This allows more effective use of the increased area of cathode  55 . This means that the contact area (electrolyzation area) between cathode  55  and conductive film  56  is further increased. 
     Space S may be formed at least on the periphery in the lengthwise direction of stacked structure  51 . 
     This structure certainly inhibits water stagnation on the periphery of electrolyzing unit  50 , thereby achieves more stable ozone (electrogenerated product) generation efficiency. 
     Positioning protrusions (housing protrusions)  221  protruding toward stacked structure  51  may be formed on the part of inner surface  22   a  of peripheral wall  22  (inner surface of the housing) that is counter to outer periphery  51   a  of stacked structure  51 . 
     In this structure, when stacked structure  51  is just placed in recession  23 , space S is formed between outer periphery (side face)  51   a  of stacked structure  51  and inner surface  22   a  of peripheral wall  22 . A gap (space  5 ), therefore, can be provided certainly between stacked structure  51  and peripheral wall  22 . 
     Cathode-side recessions  55   d  may be formed on the part of outer periphery  55   c  of cathode  55  that corresponds to the positioning protrusions (housing protrusions)  221 . 
     This structure inhibits cathode  55  from interfering with positioning protrusions (housing protrusions)  221  when cathode  55  is disposed in recession  23 . As a result, cathode  55  whose surface area is made large as much as possible can be disposed in recession  23 . 
     Conductive film-side recessions  56   b  may be formed on the part of outer periphery  56   a  of conductive film  56  that corresponds to the positioning protrusions (housing protrusions)  221 . 
     Because of this structure, when ozonized water is generated, conductive film  56  having swollen due to its absorption of water is inhibited from interfering with positioning protrusions (housing protrusions)  221 . This means that a case where swelling conductive film  56  interferes with positioning protrusions (housing protrusions)  221  and deforms can be prevented. Hence contact between the conductive film and electrodes of stacked structure  51  is made more uniform, which allows achieving more stable ozone (electrogenerated product) generation efficiency. 
     The preferred exemplary embodiments of the present disclosure have been described above. However, the present disclosure is not limited to the above exemplary embodiments and can be modified into various forms of applications. 
     For example, the ozonized water generator that generates ozone and causes it to dissolve into water to generate ozonized water has been described in the above exemplary embodiment. A substance to be generated, however, is not limited to ozone. For example, hypochlorous acid may be generated to use it for sterilization, water processing, or the like. The electrolytic solution generator may also be an apparatus that generates oxygen water, hydrogen water, chlorine-containing water, or hydrogen peroxide water. 
     Such electrolytic solution generators may be incorporated in other apparatuses and equipment and used in such a state. When the electrolytic solution generator is incorporated in a different apparatus or equipment, the electrolytic solution generator should preferably be set in a standing position in which the inlet is located on the lower side while the outlet is located on the upper side, as ozonized water generator  1  is. Positioning of the electrolytic solution generator, however, is not limited to this. It may be set in other proper positions. 
     Anode  54  may be made of a material selected from, for example, conductive silicon, conductive diamond, titanium, platinum, lead oxide, and tantalum oxide, and may be made of any given material if anode  54  made of such a material serves as an electrode capable of generating electrolyzed water and having conductivity and durability. When anode  54  is a diamond electrode, a manufacturing method for anode  54  is not limited to a film deposition method. The substrate of anode  54  may be made of a non-metal material. 
     Cathode  55  is effective if it is an electrode combining conductivity and durability. It may be made of a material selected from, for example, platinum, titanium, stainless steel, and conductive silicon. 
     In the above exemplary embodiment, the ozonized water generator in which positioning protrusions (housing protrusions)  221  extending in stacking direction Z are formed on peripheral wall  22  has been described. The housing protrusions may be formed into various shapes. For example, housing protrusions extending in the lengthwise direction (liquid-flow direction X) may be formed on a part of peripheral wall  22  that correspond to outer periphery  54   a  of anode  54  (side faces of anode  54  that extend in the lengthwise direction). In this structure, space S can be secured certainly between stacked structure  51  and peripheral wall  22 , and blocking of waterflow (liquid-flow) in space S by the housing protrusions can be inhibited. 
     Configurations of the housing and the electrolyzing unit and other detailed specifications (shapes, sizes, layout, and the like) may also be changed in a proper manner. 
     Second Exemplary Embodiment 
     A configuration of stacked structure  51  of ozonized water generator  1  according to the present disclosure will then be described in detail, as a second exemplary embodiment according to the present disclosure. 
     The same constituent elements as described in the first exemplary embodiment will be denoted by the same reference marks and will be omitted in further description. A basic configuration of ozonized water generator  1  according to the second exemplary embodiment is the same as that of ozonized water generator  1  according to the first exemplary embodiment. 
     According to the conventional technique described above, the holes formed on the cathode and the holes formed on the conductive film have the same shape. In other words, the holes on the cathode and the holes on the conductive film are formed such that their outline and size are the same in a plan view. The cathode and the conductive film are thus stacked in such a way as to superpose respective outlines of their holes one another to form the grooves. 
     However, according to the conventional technique, if the cathode is shifted relatively against the conductive film in a direction intersecting the stacking direction, it changes the electrolyzation area (contact area) between the cathode and the conductive film. This leads to a change in the density of current flow in the electrolyzing unit, thus resulting in a change in ozone generation efficiency. 
     By adopting a configuration that will be described below, an electrolytic solution generator that achieves more stable electrogenerated product generation efficiency can be obtained. 
     The following configuration example will be described on the assumption that anode  54  and conductive film  56  are configured to have substantially the same projection dimensions. 
     When stacked structure  51  is formed, both ends in the width direction of cathode  55  protrude to be further outside than those of anode  54  and conductive film  56  (a configuration shown in  FIG.  12   ). 
     If both ends in the width direction of cathode  55  are protruded to be further outside than those of anode  54  and conductive film  56 , space S is formed at least between inner surface  22   a  of peripheral wall  22  and anode  54  when stacked structure  51  is placed in recession  23 . This pace S is a space for inhibiting water stagnation between the periphery of stacked structure  51  and peripheral wall  22 . 
     Forming such a space S inhibits scales made of a calcium component or the like, the scales being produced by water electrolyzation, from piling up between stacked structure  51  and peripheral wall  22 . 
     According to the present exemplary embodiment, as shown in  FIG.  12   , space S is formed also between inner surface  22   a  of peripheral wall  22  and cathode  55 . 
     The configuration of stacked structure  51  may be based on configurations shown in  FIGS.  7  to  11   . In other words, the basic configuration of the first exemplary embodiment and detailed configurations described in the second exemplary embodiment can be combined. 
     In the following configuration example, more stable generation efficiency of ozone  70  can be achieved. 
     Specifically, in a plan view (view along the stacking direction of stacked structure  51 ), conductive film-side hole  56   c  and cathode-side hole  55   e  are configured such that their shapes (outline and size) are different from each other. 
     Conductive film-side hole  56   c  is formed as an elongated hole long and narrow in width direction Y, while cathode-side hole  55   e  is formed as a V-shaped hole with its bent portion  55   f  located on the downstream side in a plan view. In this manner, conductive film-side hole  56   c  and cathode-side hole  55   e  are made different in outline from each other in a plan view (see  FIGS.  4  and  13   ). 
     In this manner, conductive film-side hole  56   c  formed as an elongated hole long and narrow in width direction Y extends in the direction (width direction Y) perpendicular to liquid-flow direction X in a plan view (see  FIG.  13   ). This means that, in a plan view, an angle that the direction of extension of conductive film-side hole  56   c  makes with liquid-flow direction X is 90 degrees. 
     Cathode-side hole  55   e , on the other hand, has a shape such that two elongated holes, which extend from the outer side in width direction Y on the upstream side toward bent portion  55   f  located at a canter in width direction Y on the downstream side, join at bent portion  55   f  to communicate with each other. In other words, two elongated holes, which extend from bent portion  55   f  toward front ends  55   h , extend in a direction intersecting liquid-flow direction X in a plan view (see  FIG.  14   ). 
     Cathode-side hole  55   e  is formed such that front ends  55   h  are located on the outer side in width direction Y on the upstream side to bent portion  55   f . Being configured in this manner, two elongated holes making up cathode-side hole  55   e  each extend in a direction intersecting liquid-flow direction X and width direction Y (direction perpendicular to liquid-flow direction X) as well. The direction of extension of each of two elongated holes making up cathode-side hole  55   e  makes an acute angle with liquid-flow direction X, and an absolute value of the acute angle is larger than 0 degree and smaller than 90 degrees. 
     Cathode-side hole  55   e , therefore, can be formed as, for example, a V-shaped groove having one elongated hole extending in a direction tilted against liquid-flow direction X at 30 degrees and the other elongated hole extending in a direction tilted against liquid-flow direction X at −30 degrees. 
     It is unnecessary to match the absolute value of the acute angle that the direction of extension of one elongated hole makes with liquid-flow direction X to the absolute value of the acute angle that the direction of extension of the other elongated hole makes with liquid-flow direction X. In other words, it is unnecessary to make the shape of cathode-side hole  55   e  in a plan view axisymmetry with respect to a straight line passing through bent portion  55   f  and extending in liquid-flow direction X. 
     According to the present exemplary embodiment, in a state in which cathode  55  is stacked on conductive film  56 , respective directions of extension of two elongated holes making up cathode-side hole  55   e  are not parallel with the direction of extension of conductive film-side hole  56   c.    
     Conductive film-side hole  56   c  and cathode-side hole  55   e  are configured such that when cathode  55  is stacked on conductive film  56 , conductive film-side hole  56   c  and cathode-side hole  55   e  partially communicate with each other. In other words, conductive film-side hole  56   c  and cathode-side hole  55   e  are configured such that part of a plurality of elongated holes extending in different directions communicate with each other. 
     In this configuration, conductive film  56  and cathode  55  are stacked such that, in a plan view, they have intersecting portions  59  at which outer periphery (outline in a plan view)  66   d  of conductive film-side hole  56   c  intersects outer periphery (outline in a plan view)  55   g  of cathode-side hole  55   e  (see  FIG.  14   ). 
     On conductive film  56 , conductive film-side holes  56   c  are formed such that they are lined up along liquid-flow direction X. On cathode  55 , cathode-side holes  55   e  are formed such that they are lined up along liquid-flow direction X. 
     Two cathode-side holes  55   e  adjacent to each other in liquid-flow direction X are arranged such that bent portion  55   f  of one cathode-side hole  55   e  on the upstream side is located downstream to front ends  55   h  of another cathode-side hole  55   e  on the downstream side. Conductive film-side holes  56   c  and cathode-side holes  55   e  are arranged such that when cathode  55  is stacked on conductive film  56 , a plurality of conductive film-side holes  56   c  intersect one cathode-side hole  55   e.    
     Thus, in a plan view of the state in which cathode  55  is stacked on conductive film  56 , a plurality of communication regions R 1 , where cathode-side holes  55   e  communicate with conductive film-side holes  56   c , and a plurality of exposed regions R 2 , where conductive film  56  is exposed, are formed in one cathode-side holes  55   e . In other words, a plurality of intersecting portions  59  are formed in one cathode-side holes  55   e.    
     It is preferable that conductive film-side holes  56   c  each have the same shape and cathode-side holes  55   e  each have the same shape as well and that the pitch of conductive film-side holes  56   c  in liquid-flow direction X be equal to that of cathode-side holes  55   e  in liquid-flow direction X. 
     In this configuration, communication regions R 1  and exposed regions R 2  appear in a regular pattern along liquid-flow direction X. 
     In this example, cathode  55  is larger in width in width direction Y than conductive film  56 . The contact area (electrolyzation area) between cathode  55  and conductive film  56  is, therefore, can be approximated by deducting a total area of exposed regions R 2  from an area of an upper surface of conductive film  56 , that is, an area of a part of the upper surface of conductive film  56  where conductive film-side holes  56   c  are not formed. 
     Cathode  55  and conductive film  56  are configured in the above manner, in which case, even if conductive film  56  is shifted in position relatively against cathode  55  upon formation of stacked structure  51 , an amount of change in the contact area (electrolyzation area) between cathode  55  and conductive film  56  can be kept small. When such a positional shift occurs in the configuration described in the present exemplary embodiment and in the configuration achieved by the conventional technique, if an extent of the positional shift is the same in both configurations, the configuration described in the present exemplary embodiment keeps the amount of change in the electrolyzation area smaller than that in the configuration achieved by the above technique. 
     For example, as shown in  FIG.  15   , when conductive film  56  is shifted in position relatively against cathode  55  in liquid-flow direction X upon formation of stacked structure  51 , an area of one exposed region R 2  (and an area of one communication region R 1 ) changes slightly near bent portion  55   f  of cathode-side hole  55   e . The area of one exposed region R 2 , however, changes little on other parts of cathode-side hole  55   e . Thus, an amount of change in the total area of exposed regions R 2  of one cathode-side hole  55   e  is almost equal to an amount of change in the area of one exposed region R 2  near bent portion  55   f.    
     In this example, even if conductive film  56  is shifted relatively against cathode  55  in liquid-flow direction X, outer periphery (outline in a plan view)  56   a  of conductive film  56  comes in contact with cathode  55  when an extent of the positional shift is moderate. This prevents a case where the contact area between conductive film  56  and cathode  55  changes as a result of outer periphery (outline in a plan view)  56   a  of conductive film  56  shifting to stick out of cathode  55 . 
     In such a configuration, following the positional shift in liquid-flow direction X, the contact area between conductive film  56  and cathode  55  changes slightly from the contact area between conductive film  56  and cathode  55  in the case of conductive film  56  being stacked in its specified position. 
     As shown in  FIG.  16   , when conductive film  56  is shifted in position relatively against cathode  55  in width direction Y upon formation of stacked structure  51 , the area of one exposed region R 2  (and the area of one communication region R 1 ), basically, changes little. However, on a part where conductive film-side recessions  56   b  serving as the relief portions are formed, conductive film-side hole  56   c  is slightly shorter in width direction Y. On this part, therefore, the area of one exposed region R 2  changes slightly. 
     In this manner, in the case of a relative positional change in width direction Y, an amount of change in a total area of exposed regions R 2  of one cathode-side hole  55   e  is almost equal to an amount of change in the area of one exposed region R 2  on the part where conductive film-side recessions  56   b  serving as the relief portions are formed. 
     As shown in  FIG.  16   , even if conductive film  56  is shifted relatively against cathode  55  in width direction Y, outer periphery (outline in a plan view)  56   a  of conductive film  56  comes in contact with cathode  55  when an extent of the positional shift is moderate. In such a configuration, therefore, following the positional shift in width direction Y, the contact area between conductive film  56  and cathode  55  changes slightly from the contact area between conductive film  56  and cathode  55  in the case of conductive film  56  being stacked in its specified position. 
     Thus, in this configuration, a relative shift of conductive film  56  against cathode  55  in a direction along a horizontal plane (liquid-flow direction X and width direction Y) merely results in a slight shift of the contact area between conductive film  56  and cathode  55 . 
     In contrast, when the holes of the same shape are superposed one another to form the grooves, as in the case of the above conventional technique, a positional shift of conductive film  56  against cathode  55  leads to formation of exposed regions R 2 , which are not formed in a normal state without a positional shift, in the grooves. 
     In this case, therefore, a total area of exposed regions R 2  formed respectively in the grooves is equivalent to an amount of change in the contact area between conductive film  56  and cathode  55 . Exposed regions R 2  newly formed respectively in the grooves create an amount of change in the contact area between conductive film  56  and cathode  55  that is greater than an amount of change in the contact area between conductive film  56  and cathode  55  that would result in the configuration according to the present exemplary embodiment when the same extent of a positional shift occurs. 
     For example, when conductive film  56  is shifted against cathode  55  in liquid-flow direction X, it merely lead to a change in the area of exposed region R 2  near bent portion  55   f  in the configuration according to the present exemplary embodiment. In the configuration according to the conventional technique, however, this positional shift, if it is the same in extent as the positional shift in the configuration according to the present exemplary embodiment, leads to formation of exposed region R 2  which projects in liquid-flow direction X by the extent of the positional shift and extends along almost the whole of groove  52  in its width direction Y. In this manner, when conductive film  56  is shifted against cathode  55 , if an extent of the positional shift is the same in both configurations, the amount of change in the contact area between conductive film  56  and cathode  55  becomes smaller in the configuration according to the present exemplary embodiment than in the configuration according to the above technique. 
     According to the present exemplary embodiment, curved portions  56   e , which are arcuate in a plan view, are formed respectively on both ends in width direction Y of conductive film-side hole  56   c . As a result, no sharp edge is formed on outer periphery (outline in a plan view)  66   d  of conductive film-side hole  56   c.    
     Likewise, curved portions, which are arcuate in a plan view, are formed respectively on bent portion  55   f  and front ends  55   h  of cathode-side hole  55   e . As a result, no sharp edge is formed on outer periphery (outline in a plan view)  55   g  of cathode-side hole  55   e.    
     In this manner, outer periphery (outline in a plan view)  66   d  of conductive film-side hole  56   c  and outer periphery (outline in a plan view)  55   g  of cathode-side hole  55   e  are made into smooth shapes. This alleviates local concentration of an electric filed during an electrolyzing process. As a result, ozone  70  can be generated more uniformly across a part of interface  57  that is exposed to grooves  52  (see  FIG.  13   ). Hence more stable generation efficiency of ozone  70  can be achieved. 
     According to the present exemplary embodiment, groove  52  has conductive film-side hole (conductive film-side groove)  56   c  formed on conductive film  56  and cathode-side hole (electrode-side groove)  55   e  formed on cathode (electrode)  55  and communicating with conductive film-side hole  56   c.    
     In a view along stacking direction Z of stacked structure  51 , conductive film-side hole  56   c  and cathode-side hole  55   e  are different in shape from each other. 
     In this structure, even if conductive film  56  is shifted against cathode (electrode)  55  relatively in a direction intersecting stacking direction Z, a change in the contact area between conductive film  56  and cathode (electrode)  55  can be suppressed. This means that the electrolyzation area (current-carrying area) between conductive film  56  and cathode (electrode)  55  can be secured more stably. 
     Securing the electrolyzation area (current-carrying area) between conductive film  56  and cathode (electrode)  55  stably in this manner makes the density of current flow in electrolyzing unit  50  more uniform. For each product, therefore, a change in the density of current flow in electrolyzing unit  50  can be suppressed. As a result, more stable generation efficiency of ozone (electrogenerated product)  70  is achieved. 
     In this manner, according to the present exemplary embodiment, even if conductive film  56  and cathode (electrode)  55  are shifted in position against each other, more stable generation efficiency of ozone (electrogenerated product)  70  is achieved. In other words, ozonized water generator  1  with substantially constant generation efficiency of ozone (electrogenerated product)  70  can be obtained. 
     According to the present exemplary embodiment, conductive film  56  and cathode  55  are stacked such that, in a plan view along stacking direction Z of stacked structure  51 , they have intersecting portions  59  at which outer periphery (outline in a plan view)  66   d  of conductive film-side hole  56   c  intersects outer periphery (outline in a plan view)  55   g  of cathode-side hole  55   e . In this structure, when conductive film  56  and cathode (electrode)  55  are shifted relatively against each other, a change in the contact area between conductive film  56  and cathode (electrode)  55  can be suppressed more certainly. 
     According to the present exemplary embodiment, conductive film-side hole  56   c  extends in the direction intersecting liquid-flow direction X (in which a liquid flows). 
     In this structure, ozone  70  generated near interface  57  between conductive film  56  and anode  54  can be separated quickly from interface  57 . In other words, bubbles of ozone  70  generated near interface  57  is inhibited from growing bigger. 
     If ozone  70  grows into large bubbles of ozone, such bubbles of ozone, even if they are separated from interface  57 , may not dissolve into water (liquid) and keep floating therein. This may lead to a drop in a concentration of ozone (electrogenerated product)  70  dissolved in water (liquid). 
     However, if conductive film-side holes  56   c  are formed in such a way as to extend in the direction intersecting liquid-flow direction X, as described in the present exemplary embodiment, ozone  70  can be separated from interface  57  before it grows into large bubbles of ozone. This enhances the process of ozone (electrogenerated product)  70  dissolving into water (liquid). 
     According to the present exemplary embodiment, conductive film-side holes  56   c  extend in the direction intersecting liquid-flow direction X. 
     In this structure, ozone  70  generated near interface  57  between conductive film  56  and anode  54  can be separated quickly from interface  57 . 
     According to the present exemplary embodiment, the electrodes adjacent to each other are cathode  55  and anode  54 . The electrode-side grooves have cathode-side holes (cathode-side grooves)  55   e , which are formed in cathode  55  and extend in the direction intersecting liquid-flow direction X. 
     In this structure, stagnation of ozone (electrogenerated product)  70  in grooves  52  is inhibited to cause ozone  70  to flow through channel  11  more efficiently. 
     According to the present exemplary embodiment, cathode-side hole  55   e  is of the V shape with its bent portion  55   f  located on the downstream side in a view along stacking direction Z of stacked structure  51 . 
     In this structure, generated ozone (electrogenerated product)  70  migrates toward the central part of cathode-side hole  55   e , where the flow velocity is relatively high, along a slope of cathode-side hole  55   e . This process further inhibits the stagnation of ozone (electrogenerated product)  70 . As a result, ozone concentration (electrogenerated product concentration) is further enhanced. 
     It is preferable that conductive film-side holes  56   c  each have the same shape and cathode-side holes  55   e  each have the same shape as well and that the pitch of conductive film-side holes  56   c  in liquid-flow direction X be equal to that of cathode-side holes  55   e  in liquid-flow direction X. 
     This arrangement causes communication regions R 1  and exposed regions R 2  to appear in a regular pattern in liquid-flow direction X, thus reducing the effect of a positional shift more certainly. 
     It is preferable that curved portions  56   e , which are arcuate in a plan view, be formed respectively on both ends in width direction Y of conductive film-side hole  56   c.    
     Likewise, it is preferable that curved portions, which are arcuate in a plan view, be formed respectively on bent portion  55   f  and front ends of cathode-side hole  55   e.    
     This alleviates local concentration of an electric filed during the electrolyzing process. As a result, ozone  70  can be generated more uniformly across the part of interface  57  that is exposed to grooves  52 . Hence more stable generation efficiency of ozone  70  can be achieved. 
     Cathode-side holes  55   e  may be each formed into an elongated shape extending in liquid-flow direction X and be arranged such that when cathode  55  and conductive film  56  are stacked, cathode-side holes  55   e  and conductive film-side holes  56   c  cross each other crosswise in a plan view. 
     The direction of extension of conductive film-side holes  56   c  may be determined to be a direction intersecting both liquid-flow direction X and width direction Y (perpendicular to liquid-flow direction X). It is preferable in such a case that the direction of extension of conductive film-side holes  56   c  be not parallel with the direction of extension of cathode-side holes  55   e  so that conductive film-side holes  56   c  intersect cathode-side holes  55   e  when conductive film  56  and cathode  55  are stacked. 
     Conductive film-side holes  56   c  and cathode-side holes  55   e  may have shapes similar to each other so that smaller shapes are present in larger shapes when conductive film  56  and cathode  55  are stacked. 
     Conductive film-side hole  56   c  and cathode-side hole  55   e  may have a V shape and an elongated shape, respectively. 
     Configurations of the electrode case and electrode case lid and other detailed specifications (shapes, sizes, layout, and the like) may also be changed in a proper manner. 
     As described above, the present disclosure may be embodied in the following mode. 
     An electrolytic solution generator includes an electrolyzing unit having a stacked structure in which a conductive film is interpose between a plurality of electrodes adjacent to each other, the electrolyzing unit electrolyzing a liquid, and a housing in which the electrolyzing unit is placed. 
     In the housing, a channel is formed, the channel having an inlet into which a liquid to be supplied to the electrolyzing unit flows and an outlet from which an electrolytic solution generated by the electrolyzing unit flows out and causing a liquid to flow in a liquid-flow direction intersecting a stacking direction of the stacked structure. 
     In electrolyzing unit, grooves are formed as grooves which are open to the channel and to which at least a part of interfaces between the conductive film and the electrodes is exposed. 
     Each of the grooves has a conductive film-side groove formed on the conductive film and an electrode-side groove formed on the electrodes and communicating with the conductive-side groove. 
     In a view along the stacking direction of the stacked structure, the conductive film-side groove and the electrode-side groove are different in shape from each other. 
     The conductive film and the electrodes may be stacked such that, in a plan view along the stacking direction of the stacked structure, the conductive film and the electrodes have intersecting portions at each of which an outer periphery of the conductive film-side groove intersects an outer periphery of the electrode-side groove. 
     The conductive film-side groove may extend in a direction intersecting the liquid-flow direction. 
     The conductive film-side groove may extend in a direction perpendicular to the liquid-flow direction. 
     The electrodes adjacent to each other may be a cathode and an anode, the electrode-side groove may have a cathode-side groove formed on the cathode, and the cathode-side groove may extend in a direction intersecting the liquid-flow direction. 
     The cathode-side groove may be of a V shape with a bent portion located on the downstream side in a view along the stacking direction of the stacked structure. 
     The preferred exemplary embodiments of the present disclosure have been described above. However, the present disclosure is not limited to the above exemplary embodiments and can be modified into various forms of applications. 
     For example, the ozonized water generator that generates ozone and causes it to dissolve into water to generate ozonized water has been described in the above exemplary example. A substance to be generated, however, is not limited to ozone. For example, hypochlorous acid may be generated to use it for sterilization, water processing, or the like. The ozonized water generator may also work as an apparatus that generates oxygen water, hydrogen water, chlorine-containing water, or hydrogen peroxide water. 
     Such electrolytic solution generators may be incorporated in other apparatuses and equipment and used in such a state. When the electrolytic solution generator is incorporated in a different apparatus or equipment, the electrolytic solution generator should preferably be set in a standing position in which the inlet is located on the lower side while the outlet is located on the upper side, as ozonized water generator  1  is. Positioning of the electrolytic solution generator, however, is not limited to this. It may be set in other proper positions. 
     Anode  54  may be made of a material selected from, for example, conductive silicon, conductive diamond, titanium, platinum, lead oxide, and tantalum oxide. Anode  54  may be made of any given material if such a material makes up an electrode having enough conductivity and durability for generating electrolyzed water. When anode  54  is a diamond electrode, a manufacturing method for anode  54  is not limited to a film deposition method. The substrate of anode  54  may be made of a non-metal material. 
     Cathode  55  is effective if it is an electrode combining conductivity and durability. It may be made of a material selected from, for example, platinum, titanium, stainless steel, and conductive silicon. 
     Cathode-side holes  55   e  may be each formed into an elongated shape extending in liquid-flow direction X and be arranged such that when cathode  55  and conductive film  56  are stacked, cathode-side holes  55   e  and conductive film-side holes  56   c  cross each other crosswise in a plan view. 
     The direction of extension of conductive film-side holes  56   c  may be determined to be a direction intersecting both liquid-flow direction X and width direction Y (perpendicular to liquid-flow direction X). It is preferable in such a case that the direction of extension of conductive film-side holes  56   c  be not parallel with the direction of extension of cathode-side holes  55   e  so that conductive film-side holes  56   c  intersect cathode-side holes  55   e  when conductive film  56  and cathode  55  are stacked. 
     Conductive film-side holes  56   c  and cathode-side holes  55   e  may have shapes similar to each other so that smaller shapes are present in larger shapes when conductive film  56  and cathode  55  are stacked. 
     Conductive film-side hole  56   c  and cathode-side hole  55   e  may have a V shape and an elongated shape, respectively. 
     Configurations of the electrode case and electrode case lid and other detailed specifications (shapes, sizes, layout, and the like) may also be changed in a proper manner. 
     As described above, according to the present disclosure, the electrolytic solution generator offers a special effect of inhibiting pressure application by scales to the housing and the electrolyzing unit. The present disclosure can be applied to electrical equipment that uses an electrolytic solution generated by the electrolytic solution generator and to liquid reformer or the like equipped with the electrolytic solution generator, and is useful in such applications.