CN107656334A - Polyvinyl alcohol film - Google Patents

Abstract

The present invention relates to Polyvinyl alcohol film.There is provided can yield PVA based polymer films of the few light polarizing film of manufacturing defect and Polarizer well, and provide and can manufacture from the winding beginning portion of PVA based polymer films up to the difference of the surface characteristic of winding ending portion is small and the light polarizing film of stay in grade and the film roll of Polarizer.The present invention provides PVA based polymer films, wherein, it is 400 μm from film surface indentation and area²The number for the shortcomings that above and depth is more than 0.3 μm is 0.25/m²Below；With offer film roll, it is that the PVA based polymers film of strip continuously winds the film roll formed, wherein, for being 400 μm from film surface indentation and area²The shortcomings that above and depth is more than 0.3 μm, the number of the shortcoming of the winding ending portion of PVA based polymer films are less than 1.4 times relative to the number of the shortcoming of the winding beginning portion of PVA based polymer films.

Description

Polyvinyl alcohol film

The present patent application is PCT Patent Application PCT/JP2013/057792, and the applying date is March 19, invention name in 2013 The referred to as divisional application of the application for a patent for invention of " Polyvinyl alcohol film ", female case enter the Application No. of China 201380018266.2。

Technical field

The present invention relates to the useful Polyvinyl alcohol film such as the initial film as light polarizing film manufacture（Hereinafter, have When " polyvinyl alcohol " is referred to as " PVA "）, it is continuous using the manufacture method and light polarizing film of its light polarizing film, PVA based polymer films Wind the film roll formed and the manufacture method of PVA based polymer films.

Background technology

PVA based polymer films be used to utilize and the related uniqueness such as transparent optical characteristics mechanical strength water solubility The various uses of property, it is particularly nearest, expand by the use of its excellent optical characteristics and be used as composition liquid crystal display（LCD） Basic constituent element be Polarizer light polarizing film manufacture raw material（Initial film）Purposes.Although in LCD monitor, liquid crystal Large screen rapidly develops in the field of TV, but product, yield rate can not be assemblied in if Polarizer has defect（Product is received Rate）Reduce, thus need the Polarizer and light polarizing film that defect is less compared with present.

However, the optical film on including light polarizing film and diaphragm, phase retardation film etc., it is hitherto known have it is various Technology.For example, molten polymer is made as the thermoplastic resins such as polyester, polyamide, polyolefin are heated into more than its fusing point, will When it is extruded and cooled down by nozzle to manufacture the film for optical applications etc., oligomer present in polymer （Oligomer）Separated out in film manufacture to surface and be attached to the surface of casting drum or roller, turned into the surface defectivity of film, be made as For solving the scheme of the problem, it is known to use a kind of scheme of the manufacture device of film, the device has used the table of outer peripheral face Surface roughness is that below 1S and surface have and contain carbon atom relative to chromium atom（In terms of atom number）0.5~5% chromium plating quilt The film manufacture roller or roller of film（With reference to patent document 1）.Specifically described in patent document 1：By poly terephthalic acid second two Alcohol ester melts at 275 DEG C, extruded by T moulds and be quenched with the casting drum for being cooled to 25 DEG C and after being made as amorphous sheet material, When being heated or cooled by the more metallic rolls in the downstream for being configured at the casting drum, one as the more metallic rolls Part, use the roller with specific chromium plating epithelium.

In addition, it is cast by high-molecular resin solution when film is manufactured on support with solution film-forming, in order to be eliminated Surface defectivity（The shortcomings that being floated on film surface with overshooting shape）And the useful transparency and surface are excellent on optical applications Different high molecula resin film, and number the shortcomings that make to be present in the specific dimensions on support surface used in per unit area Below special value（With reference to patent document 2）.Specifically described in patent document 2：Using by aromatic polycarbonate resin It is dissolved in solution and the support with specific surface characteristic that the mixed solvent of ethanol and dichloromethane forms（By SUS- The 316 mirror ultrafinish plates formed）, their temperature is adjusted to 15 DEG C or so, by the solution hardened coating on support And be dried, and it is made as aromatic copolycarbonate film.

And then, it is also known that by by the membranaceous thermoplastic resin from extruder melting extrusion（Contain ester ring type structure Polymer or cellulose esters etc.）When the melting casting film method cooled down with chilling roll is to manufacture optical film, as disappearing The method of the problem of dirt or foreign matter are strongly adhere to chilling roll and produce the open defect for being referred to as " weighing wounded " etc., it is to make Organic solvent is attached to the surface of chilling roll, then wipes the surface of chilling roll by chilling roll table by wiping arrangement The dirt in face removes together with organic solvent, then makes to be attached to the wiping by the membranaceous thermoplastic resin of extruder melting extrusion Chilling roll surface portion after wiping simultaneously is cooled down, and thus manufactures optical film（With reference to patent document 3）.Remember in patent document 3 Carry, the mixture melting extrusion of the hydride containing norbornene polymer obtained therefrom through ring opening polymerization or cellulose acetate propionic ester makes Membranaceous resin melt is sealed at the chilling roll for possessing specific clearing apparatus（Hardening chromium plating quilt with Vickers hardness 800 Film surface or the noncrystalline chromium plating envelope surface of Vickers hardness 1200）, transport while cooling and solidifying, and be made as resin sheet Material.

Prior art literature

Patent document

Patent document 1:Japanese Unexamined Patent Publication 9-207210 publications

Patent document 2:Japanese Unexamined Patent Publication 2000-84960 publications

Patent document 3:Japanese Unexamined Patent Publication 2006-82261 publications

Patent document 4:JP 1-19477 publications

Patent document 5:Japanese Unexamined Patent Publication 2005-238833 publications

Patent document 6:Japanese Unexamined Patent Publication 9-1568 publications

Patent document 7:Japanese Unexamined Patent Publication 2001-315138 publications.

The content of the invention

Invention technical problems to be solved

If however, only use above-mentioned conventional technology merely, it is difficult to few inclined of horizontal manufacturing defect required in recent years Light film, Polarizer.That is, it is necessary to which thermoplastic resin is heated to more than its fusing point to be made as melt polymerization in the method for patent document 1 Thing, but PVA based polymers are in addition to special modified PVA based polymer, are not thermoplastic resin, it is difficult to by this film Method is used in the manufacture of PVA based polymer films, that is, allows to use, can not also obtain the excellent film of surface characteristic.In addition, make For the film-forming method of PVA based polymer films, it is known to using PVA based polymers be dissolved in film stoste that liquid medium forms or The film stoste formed containing PVA based polymers and liquid medium and by the melting of PVA based polymers, by it on metal support The method for being cast and drying to be film-made, but this method is with will be substantially free of liquid medium as described in Patent Document 1 The method that molten polymer is cooled down and is film-made on casting drum differs widely, thus assume that merely using patent document Film manufacture roller described in 1, using above-mentioned film stoste, even if by its in the film manufacture with being cast and done on roller It is dry and manufacture PVA based polymer films, it also can not fully control the table for being present in chromium plating envelope possessed by the film manufacture roller Fine shortcoming caused by the microcrack in face, the Polarizer or light polarizing film of the PVA based polymers film manufacture obtained by use can not yet Fully realize level of quality required in recent years.

On the other hand, patent document 2, which is related to, to be flowed using macromolecule resin and solvent as the solution of principal component on support The film-forming method delay, being dried and remove solvent, even if can be by merely using the method for patent document 2 to eliminate The shortcomings that film surface is floated with overshooting shape, also can not fully control from film surface indentation the shortcomings that, PVA based polymers obtained by use The Polarizer or light polarizing film of film manufacture can not also realize level of quality required in recent years.

It is with cold by the fused mass of thermoplastic resin in addition, the method for patent document 3 is identical with the method for patent document 1 But the method for roller cooling, thus be difficult to be used for the method for patent document 3 in the manufacture of PVA based polymer films, even if can be with Use, can not also obtain the excellent film of surface characteristic.Moreover, it is assumed that the wiping method described in patent document 3 is merely used, Film stoste that liquid medium forms is dissolved in using PVA based polymers or containing PVA based polymers and liquid medium and by PVA The film stoste that based polymer melting forms, even if it to be cast and dry to manufacture PVA based polymers on metal support Film, the shortcomings that also can not fully controlling concavity, be due to metal support surface is contacted with wiping arrangement and in metal on the contrary Support surface produces the defects of scratch, and the surface characteristic of the PVA based polymer films of gained may be made to be deteriorated on the contrary.

Under the condition as mentioned above, it is an object of the invention to provide being capable of the efficiency few polarisation of manufacturing defect well The PVA based polymer films of film and Polarizer.In addition, the present invention also aims to provide film roll, the film roll is the PVA of strip Based polymer film continuously winds the film roll formed, and it can be manufactured from the winding beginning portion of PVA based polymer films up to winding The difference of the surface characteristic of latter end is small and the light polarizing film and Polarizer of stay in grade.

In addition, PVA based polymers film is made as more because of keeping or the easiness transported or the reason for can be used continuously etc. The PVA based polymers film of strip continuously winds the form of the film roll formed, in this film roll, because intermembranous sliding is bad etc. And film is easily produced fold, the reason for quality that this fold easily becomes manufactured light polarizing film reduces.On the other hand, it is right In light polarizing film, also require to reduce the dyeing inequality different from drawbacks described above sometimes.Therefore, the present invention on the other hand, its purpose The PVA systems that film roll is difficult to produce fold and the uneven light polarizing film being reduced of dyeing can easily be manufactured by being to provide Polymer film and it is continuously wound to the film roll formed.

In addition, being used as by PVA based polymers film in situation of the initial film to manufacture light polarizing film, generally PVA systems are polymerize Thing film implements dyeing, uniaxial tension, fixing process etc., but when carrying out uniaxial tension with dry type, in dyeing process or bearing In science and engineering sequence, and when carrying out uniaxial tension with wet type, except these processes, swelling process before uniaxial tension or in list In axle stretching process, part dissolution in used processing bath of PVA based polymers, the PVA systems of dissolution be present Polymer is separated out in processing is bathed and is attached to film or is separated out on film, and the light polarizing film of gained is residued in as foreign matter, and is had The situation for reducing its quality, yield.Therefore, it is an object of the invention to provide the light polarizing film for manufacturing this few foreign The light polarizing film of the manufacture method of light polarizing film and the few foreign manufactured by this method.

And then the present invention also aims to provide easily manufacture PVA based polymers film as described above, film roll PVA based polymer films manufacture method.

For solving the method for technical problem

The present inventor furthers investigate to achieve these goals and repeatedly, as a result finds, in the metal support such as roller or band When the PVA based polymers of solution state or molten condition are cast on surface and are dried to manufacture PVA based polymer films, it is present in Can adhere in sub-fraction in the numerous cracks on the surface of the metal support foreign matter that is considered as buildup of resin thing and by its Caused convex form be transferred to film etc. and formed from film surface indentation the shortcomings that number more than PVA based polymer films；And For this PVA based polymers film, in the light polarizing film being produced from it, defect becomes more in Polarizer, and having can not fully realize closely Required level of quality over year, or it is related to the yield reduction of light polarizing film, Polarizer etc. the problem of.

Then, find in the metal support that using surface there is chromium coating and case hardness to be specific scope, By the common processing implemented before film starts to metal support surface of such as polishing grinding etc., it can easily reduce and deposit Be the number of the crackle on metal support surface, can more reduce than ever gained PVA based polymer films from film surface The number of the shortcomings that depression, can be good with yield when this PVA based polymers film to be used as to the initial film of light polarizing film manufacture Ground manufacturing defect is few and meets the light polarizing film of level of quality required in recent years, Polarizer.

In addition, in addition to above-mentioned opinion, it was found that：It is specific there is chromium coating and case hardness using surface , can also be by from film surface indentation even if continuous manufacture PVA based polymer films for a long time during the metal support of scope The variation of the number of shortcoming is maintained at relatively in the past lower level, for example, the PVA based polymers film in manufacture strip is continuously wound During the film roll formed, the surface untill winding ending portion from the winding beginning portion of PVA based polymer films can be reduced The difference of characteristic, the light polarizing film that can manufacture stay in grade and the film roll of Polarizer can be readily derived.

And then it also found that there is the metal support that chromium coating and case hardness be specific scope using surface When, the surface characteristic that can be readily derived the two sides of film is the PVA based polymer films of specific scope, the PVA based polymer films Continuously wind and be difficult to produce fold in the film roll formed, can suppress the quality of light polarizing film reduces, and is polymerize according to the PVA systems Thing film can be readily derived the uneven light polarizing film being reduced of dyeing；Passing through specific side with the PVA based polymers film in use When legal system makes light polarizing film, the light polarizing film of few foreign can be readily derived.

The present inventor is further studied repeatedly based on above-mentioned opinion, so as to complete the present invention.

That is, the present invention relates to：

［ 1 ］ PVA based polymers film（Hereinafter, the PVA based polymers film is referred to as " PVA based polymer films sometimes（1）”）, wherein, It it is 400 μm from film surface indentation and area²The number for the shortcomings that above and depth is more than 0.3 μm is 0.25/m²Below；

The PVA based polymer films of ［ 2 ］ above-mentioned ［ 1 ］, wherein, the number of aforesaid drawbacks is 0.15/m²Below；

［ 3 ］ the PVA based polymer films of above-mentioned ［ 1 ］ or ［ 2 ］, wherein, contained PVA based polymers is poly- in PVA based polymer films Right is more than 3000 and less than 10000；

［ 4 ］ the PVA based polymer films of any one of above-mentioned ［ 1 ］~［ 3 ］, it is the PVA based polymer films of strip；

The PVA based polymer films of ［ 5 ］ above-mentioned ［ 4 ］, its length are more than 6000m；

［ 6 ］ the PVA based polymer films of above-mentioned ［ 4 ］ or ［ 5 ］, wherein, aforesaid drawbacks be included in film length direction on substantially with Certain interval and be there is essentially on the width of film in same position the shortcomings that；

［ 7 ］ film roll（Hereinafter, the film roll is referred to as " film roll sometimes（1）”）, its be strip PVA based polymers film continuously winding and Into film roll, wherein, for being 400 μm from film surface indentation and area²The shortcomings that above and depth is more than 0.3 μm, PVA The number of the shortcoming of the winding ending portion of based polymer film lacks relative to this of the winding beginning portion of PVA based polymer films The number of point is less than 1.4 times；

The film roll of ［ 8 ］ above-mentioned ［ 7 ］, wherein, the number of aforesaid drawbacks is 0.25/m²Below；

The film roll of ［ 9 ］ above-mentioned ［ 7 ］, wherein, the number of aforesaid drawbacks is 0.15/m²Below；

［ 10 ］ film roll of any one of above-mentioned ［ 7 ］~［ 9 ］, wherein, contained PVA based polymers is poly- in PVA based polymer films Right is more than 3000 and less than 10000；

［ 11 ］ film roll of any one of above-mentioned ［ 7 ］~［ 10 ］, wherein, the length of PVA based polymer films is more than 6000m；

［ 12 ］ film roll of any one of above-mentioned ［ 7 ］~［ 11 ］, wherein, aforesaid drawbacks be included in film length direction on substantially with Certain interval and be there is essentially on the width of film in same position the shortcomings that；

［ 13 ］ PVA based polymers film（Hereinafter, the PVA based polymers film is referred to as " PVA based polymer films sometimes（2）”）, wherein, When determining r.m.s. roughness respectively on the two sides to film, the difference of 2 r.m.s. roughnesses of gained is more than 0.3nm and 10nm Hereinafter, less r.m.s. roughness is below 10nm；

The PVA based polymer films of ［ 14 ］ above-mentioned ［ 13 ］, wherein, larger r.m.s. roughness is more than 1nm and below 20nm；

［ 15 ］ the PVA based polymer films of above-mentioned ［ 13 ］ or ［ 14 ］, it is the PVA based polymer films of strip；

The PVA based polymers film of ［ 16 ］ above-mentioned ［ 15 ］ continuously winds the film roll formed（Hereinafter, the film roll is referred to as " film roll sometimes （2）”）；

［ 17 ］ manufacturer of the PVA based polymers film of any one of above-mentioned ［ 13 ］~［ 15 ］ as the light polarizing film of initial film is used Method, this method have dyeing process, uniaxial tension process, fixing process process and drying process, are exiting into drying process When preceding last processing is bathed, it is more than 30 ° and less than 85 ° to handle the liquid level of bath and film surface angulation, and film is upper The face of square side is the face for having in Polyvinyl alcohol film less r.m.s. roughness；

［ 18 ］ light polarizing film manufactured by the manufacture method of above-mentioned ［ 17 ］；

［ 19 ］ manufacture method of PVA based polymers film, it is included in surface, and there is chromium coating, case hardness to be calculated as with Vickers hardness 550HV less than 900HV, surface temperature be more than 50 DEG C and less than 115 DEG C metal support surface on, by solution The process that the PVA based polymers of state or molten condition are cast and dried to be filmed；By solution state or melting Before the PVA based polymers of state start curtain coating, the area on the surface of metal support（Breadth Maximum multiplies with maximum end spacing Product）For 200 μm²The number of crackle above is 0.7/mm²Below；

The manufacture method of ［ 20 ］ above-mentioned ［ 19 ］, wherein, the PVA based polymers of solution state or molten condition are poly- containing PVA systems The form of the film stoste of compound and water；

［ 21 ］ manufacture method of above-mentioned ［ 19 ］ or ［ 20 ］, wherein, the degree of polymerization of foregoing PVA based polymers for more than 3000 and Less than 10000；

［ 22 ］ manufacture method of any one of above-mentioned ［ 19 ］~［ 21 ］, wherein, the case hardness of aforementioned metal support is with Vickers Hardness is calculated as 600HV less than 800HV；

［ 23 ］ manufacture method of any one of above-mentioned ［ 19 ］~［ 22 ］, it has and with more than 0.5 DEG C/h of ramp rates makes table There is chromium coating, case hardness to be calculated as surface temperatures of the 550HV less than 900HV metal support with Vickers hardness in face For more than 50 DEG C and less than 115 DEG C of process；

［ 24 ］ manufacture method of any one of ［ 19 ］~［ 23 ］, it is manufacture any one of above-mentioned ［ 1 ］~［ 6 ］ and ［ 13 ］~［ 15 ］ PVA based polymer films method.

Invention effect

Being capable of the yield PVA systems of the few light polarizing film of manufacturing defect and Polarizer polymerization well according to the present invention it is possible to provide Thing film.In addition, according to the present invention it is possible to provide film roll, the film roll is that the PVA based polymers film of strip continuously winds the film formed Volume, it can be manufactured from the winding beginning portion of PVA based polymer films up to the difference of the surface characteristic of winding ending portion is small And the light polarizing film and Polarizer of stay in grade.

It is difficult to produce fold in addition, can be provided in film roll according to the present invention, and it is uneven easily to manufacture dyeing The PVA based polymers film for the light polarizing film being reduced and it is continuously wound to the film roll formed and for manufacturing few foreign The light polarizing film of the manufacture method of the light polarizing film of light polarizing film and the few foreign manufactured by this method.

And then according to the present invention may also provide can easily manufacture above-mentioned PVA based polymers film, film roll PVA systems gather The manufacture method of compound film.

Embodiment

Hereinafter, the present invention is further illustrated.

［ PVA based polymer films（1）

The PVA based polymer films of the present invention（PVA based polymer films（1））In, it is 400 μm from film surface indentation and area²With The shortcomings that upper and depth is more than 0.3 μm（Hereinafter, the shortcoming is referred to as " shortcoming A " sometimes）Number be 0.25/m²Below. As shortcoming present in plastic foil, can enumerate：Space in film（Bubble）；The so-called flake being mixed into caused by attachment of foreign matter； Caused scar in the operation of film（The mostly depression of trench）；The shortcomings that caused by convex form transfer on film forming apparatus etc., this Inventor has found, by especially controlling disadvantages mentioned above A number, then can be achieved being capable of the yield few polarisation of manufacturing defect well The excellent effect of film, Polarizer etc..For shortcoming A, the transfer of the convex form on above-mentioned film forming apparatus be considered as reason it 1, particularly when the metal such as roller, band support is used as described below to manufacture PVA based polymer films, it is believed that one of its reason Convex form caused by the foreign matter for the buildup of resin thing for being regarded as being attached on metal support is needed on film.Due to such Reason and when producing shortcoming A on the PVA based polymer films of strip, at least a portion in shortcoming A has following tendencies：In film Length direction on it is substantially multiple substantially at certain intervals and on the width of film（Such as more than 3）It is arranged in Identical position.Here, it is above-mentioned substantially at certain intervals, typically correspond to the 1 of the metal support such as roller or band Zhou great little length（All-round length）, but according to situation, the integral multiple of the length of 1 week size is also corresponded to sometimes.In addition, foreign matter Caused convex form can be formed on metal support it is multiple, thus as described above arrangement the shortcomings that A group also may be present it is more It is individual.

As described above, the PVA based polymer films of the present invention（1）The middle number for needing shortcoming A is 0.25/m²Below.Lack If point A number is more than 0.25/m², then defect becomes more in the light polarizing film that is produced from it, Polarizer, can not fully realize in recent years Carry out required level of quality, or cause the yield of these products to drop due to the light polarizing film more than defect, Polarizer is discarded etc. It is low.From this point of view, shortcoming A number is preferably 0.20/m²Below, it is more preferably 0.15/m²Below, further Preferably 0.10/m²Below, it is particularly preferably 0.075/m²Below.

On the other hand, the lower limit for shortcoming A number is not required to be defined, and when extreme reduces shortcoming A number, has It may be used in and set the cost of membrane equipment extremely to become high, thus shortcoming A number is preferably 0.001/m²Above, more Preferably 0.003/m²Above, more preferably 0.005/m²More than.

It from film surface indentation and area is 400 μm that shortcoming A, which is,²The shortcomings that above and depth is more than 0.3 μm.Here, Shortcoming A can be from any surface in the two sides of film towards film inner recess, and generally, shortcoming A major part is from being film-made when institute The aftermentioned metal support contact used facing to film inner recess.In addition, shortcoming A area means shortcoming A opening portion Area.And then shortcoming A depth means that from shortcoming A opening portion be vertical direction relative to film surface, and most deep position The depth at place.

Shortcoming A number（Unit is individual/m²）It can be lacked by being found from being used as one end of PVA based polymer films of object Point A, by the area of the PVA based polymer films checked untill 10 shortcoming A are found（Unit is m²）Divided by 10（It is individual）And Obtain, specifically, can by embodiment method described later obtain.Here, whether the judgement for being shortcoming A can make each shortcoming Carried out with non-planar contact surfaces form measuring instrument.

PVA based polymer films（1）Shape be not particularly limited, by the PVA based polymer films（1）As light polarizing film system In situation for the initial film made etc., from can productivity ratio well continuously manufacture light polarizing film grade, the preferably PVA of strip Based polymer film.

The length of the PVA based polymer films of the strip is not particularly limited, and can correspond to PVA based polymer films（1）'s Purposes etc. and suitably set, specifically, the length be preferably more than 1000m, more preferably more than 4000m, more preferably More than 6000m, particularly preferably more than 7000m, it is most preferably more than 8000m.In particular according to PVA based polymers film described later Manufacture method, the shortcomings that PVA based polymer films can be reduced A number, while even if gather through continuous manufacture PVA systems for a long time The variation of shortcoming A number can also be maintained at low level by compound film, even thus when above-mentioned length is longer（Example Such as more than 6000m）, can also easily obtain the PVA based polymer films that shortcoming A number is reduced.Then, utilization is this When longer PVA based polymers film continuously manufactures light polarizing film, can through long-time stable yield manufacturing defect it is few, and meet near The product of required level of quality over year, further, it is also possible to reduce with the trouble or the loss of time for changing film roll.Strip The upper limits of length of PVA based polymer films be not particularly limited, weight or roll neck excessively become when film roll is being made as if long Greatly etc., operability reduces, and keeping or transport have time-varying difficulty etc., thus the length is preferably below 30000m, is more preferably Below 25000m, more preferably below 20000m.

The width of the PVA based polymer films of strip is not particularly limited, such as can be more than 0.5m, due to needing in recent years Seek the light polarizing film of wide cut, therefore preferably more than 1m, more preferably more than 2m, more preferably more than 4m.The PVA systems of the strip The upper limit of the width of polymer film is not particularly limited, if the width is wide, light polarizing film is being manufactured with practical device In situation etc., there is the tendency for being difficult to equably be stretched, thus the width of PVA based polymer films is preferably below 7m.

PVA based polymer films（1）Thickness be not particularly limited, it is suitable to can correspond to purposes of PVA based polymer films etc. Preferably set, specifically, the thickness is preferably less than 300 μm, more preferably less than 150 μm, more preferably less than 100 μm. In addition, thinner light polarizing film is also required in recent years, from such viewpoint etc., PVA based polymer films（1）Thickness be preferably Less than 45 μm, more preferably less than 35 μm, more preferably less than 25 μm.PVA based polymer films（1）The lower limit of thickness do not have Have special limitation, from can more successfully manufacture light polarizing film in terms of grade, the thickness is preferably more than 3 μm, more preferably 5 More than μm.

As composition PVA based polymer films（1）PVA based polymers, can use to polymerising ethylene base ester system's monomer and Vinyl esters based polymer carry out saponification and manufacture those.As vinyl esters system monomer, can enumerate for example：Formic acid second Alkene ester, vinyl acetate, propionate, vinyl valerate, vinyl laurate, stearic acid vinyl ester, vinyl benzoate, Pivalic acid vinyl acetate, tertiary ethylene carbonate etc., wherein, preferred vinyl acetate.

Above-mentioned vinyl esters based polymer is preferably that the one kind or two or more vinyl esters system list as monomer is used only Obtained from body those, be more preferably used only as obtained from a kind of vinyl esters system monomer of monomer those, but can also It is the copolymer of one kind or two or more vinyl esters system monomer and other monomers that can be copolymerized therewith.

It is able to can be enumerated for example with other monomers of vinyl esters system monomer copolymerization as this：Ethene；Propylene, 1- fourths The alkene of the carbon numbers such as alkene, isobutene 3~30；Acrylic acid or its salt；Methyl acrylate, ethyl acrylate, acrylic acid positive third Ester, acrylic acid isopropyl alcohol ester, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, 2-EHA, third The acrylate such as olefin(e) acid dodecyl ester, octadecyl acrylate；Methacrylic acid or its salt；Methyl methacrylate, first Base ethyl acrylate, n propyl methacrylate, methacrylic acid isopropyl alcohol ester, n-BMA, methacrylic acid Isobutyl ester, Tert-butyl Methacrylate, 2-Ethylhexyl Methacrylate, lauryl methacrylate, methacrylic acid The methacrylates such as stearyl；Acrylamide, N methacrylamide, N- ethyl acrylamides, N, N- dimethyl propylenes Acrylamide, DAAM, acrylamide propane sulfonic acid or its salt, acrylamide propyl-dimethyl amine or its salt, N- hydroxyl first The acrylamide derivatives such as base acrylamide or derivatives thereof；Methacrylamide, N- methyl methacrylamides, N- ethyl first Base acrylamide, Methacrylamide propane sulfonic acid or its salt, dimethylaminopropyl methacrylamide or its salt, N- methylol first The methacrylamide derivatives such as base acrylamide or derivatives thereof；N- vinyl formamides, N- vinyl acetamides, N- ethene The N- vinylamides such as base pyrrolidones；Methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl-ethylene Base ether, n-butyl vinyl ether, IVE, tert-Butyl vinyl ether, dodecyl vinyl, stearyl ethene The vinyl ethers such as base ether；The vinyl cyanide base such as acrylonitrile, methacrylonitrile；Vinyl chloride, vinylidene chloride, vinyl fluoride, inclined fluorine The ethylene halides such as ethene；The allyl compounds such as allyl acetate, allyl chloride；Maleic acid or its salt, ester or acid anhydrides；Itaconic acid Or its salt, ester or acid anhydrides；The vinyl silyl groups compound such as vinyltrimethoxy silane；Methylvinyl acetate etc..It is above-mentioned Vinyl esters based polymer can have the one kind or two or more construction unit derived from above-mentioned other monomers.

The ratio shared in above-mentioned vinyl esters based polymer from the construction unit of above-mentioned other monomers is without spy Do not limit, it is preferably 15 moles of below %, more excellent based on the molal quantity for the entire infrastructure unit for forming vinyl esters based polymer Elect 5 moles of below % as.

The degree of polymerization of PVA based polymers need not limit, due to inclining with the reduction film-strength reduction with the degree of polymerization To, thus preferably more than 200, more preferably more than 300, more preferably more than 400, particularly preferably more than 500.This Outside, degree of polymerization viscosity of the aqueous solution or the PVA based polymers of melting if too high uprises, and the tendency that film becomes difficult be present, thus Preferably less than 10000, less than 9000, more preferably less than 8000, particularly preferably less than 7000 are more preferably.This In, the degree of polymerization of PVA based polymers means the average degree of polymerization of the record measure according to JIS K6726-1994, can be according to general PVA based polymers resaponifying, carry out it is refined after the inherent viscosity ［ η ］ that is determined in 30 DEG C of water（Unit：Decilitre/g）By following formula Obtain.

The degree of polymerization=（［ η ］ × 10³/8.29）^（1/0.62）

In addition, using PVA based polymer of the degree of polymerization more than 3000 and in less than 10000 scope and pass through aftermentioned method system When making PVA based polymer films, the minimum PVA based polymer films of shortcoming A number can be obtained, and even if through continuous for a long time The variation of shortcoming A number can also be kept low by manufacture PVA based polymers film, therefore it is preferred that.From such viewpoint Set out, the degree of polymerization of PVA based polymers is more preferably more than 4000, more preferably more than 5000.It should illustrate, by making The reasons why realizing the effect above with PVA based polymers of the degree of polymerization more than 3000 and in less than 10000 scope is not necessarily Clearly, but think that the PVA based polymers of solution state or molten condition are more easily accessible the surface that is present in metal support Crackle, then in PVA based polymers film the shortcomings that A number more increase, therefore speculate be using the above-mentioned degree of polymerization PVA systems polymerization It is above-mentioned during thing to enter the reason being inhibited.

The saponification degree of PVA based polymers is not particularly limited, and can use such as 60 moles more than % PVA based polymers, But especially it is used as by PVA based polymers film in situations of initial film of optical film manufacture such as light polarizing film etc., PVA based polymers Saponification degree be preferably 95 moles of more than %, more preferably 98 moles of more than %, more preferably 99 moles of more than %.Here, The saponification degree of PVA based polymers mean relative to possessed by PVA based polymers, vinyl alcohol units can be converted into by saponification Construction unit（Typically vinyl esters system monomeric unit）With the total molal quantity of vinyl alcohol units, the vinyl alcohol units are rubbed Ratio shared by your number（Mole %）.The saponification degree of PVA based polymers can be measured according to JIS K6726-1994 record.

In manufacture PVA based polymer films（1）When, can be used alone PVA based polymers, can also and with the degree of polymerization, 1 or more than 2 mutually different PVA based polymers of more than two kinds in saponification degree, modification degree etc..PVA based polymer films （1）In PVA based polymers containing ratio be preferably more than 50 mass %, more preferably more than 70 mass %, more preferably More than 85 mass %.

PVA based polymer films（1）Preferably comprise plasticizer.PVA based polymer films（1）, can be to prevent by containing plasticizer The generation of fold when being only made as film roll or process when making secondary operation are improved by property.It is preferably polynary as plasticizer Alcohol, it can specifically enumerate for example：Ethylene glycol, glycerine, two glycerine, propane diols, diethylene glycol (DEG), triethylene glycol, tetraethylene glycol, trimethylolpropane Deng.These plasticizer can be used alone or and use two or more.In these plasticizer, mixed from PVA based polymers Property or the viewpoint such as acquired are set out, preferably ethylene glycol or glycerine.

PVA based polymer films（1）In the content of plasticizer relative to the mass parts of PVA based polymers 100 be preferably 1~30 In the range of mass parts, in the range of more preferably 3~25 mass parts, in the range of more preferably 5~20 mass parts.

PVA based polymer films（1）, performance, raising PVA from the metal support stripping improved from used in its manufacture The viewpoints such as the operability of based polymer film are set out, and preferably comprise surfactant.The species of surfactant is not particularly limited, Preferably using anionic property or the surfactant of nonionic.

As anionic surfactant, can enumerate for example：The sulfuric esters such as the carboxylic acid types such as potassium laurate, sulfuric acid monooctyl ester Sulfonic acid types such as type, dodecylbenzenesulfonate etc..

As nonionic surfactant, can enumerate for example：The alkyl ether types such as polyoxyethylene oleyl ether, polyoxyethylene are pungent The alkyl such as the alkyl esters such as the alkyl phenyl such as base phenyl ether ether type, polyoxyethylene laurate, polyoxyethylene laural base amino ethers The polypropylene glycol ether type such as alkylamide type, the polyoxyethylene poly-oxygen propylene aethers such as amine type, polyoxyethylene laural acid amides, laurate diethyl Allyl phenyl ether type such as the alkylol amide types such as alkylolamides, oleic acid diethyl amide, polyoxy alkylidene allyl phenyl ether etc..

These surfactants can be used alone or and use two or more.

PVA based polymer films（1）In surfactant content, from the performance or PVA systems peeled off by metal support The viewpoints such as the operability of polymer film are set out, relative to the mass parts of PVA based polymers 100, the preferably model of 0.01~1 mass parts In enclosing, in the range of more preferably 0.02~0.5 mass parts, in the range of more preferably 0.05~0.3 mass parts.

PVA based polymer films（1）In can also further contain above-mentioned PVA based polymers, plasticizer and surface as needed Other compositions beyond activating agent.As this other compositions, can enumerate for example：Moisture, antioxidant, ultra-violet absorber, Lubricant, colouring agent, filler（Inorganic particles, starch etc.）, preservative, mould inhibitor, other high scores beyond mentioned component Sub- compound etc..

［ film roll（1）

The film roll of the present invention（Film roll（1））It is that the PVA based polymers film of strip continuously winds the film roll formed, wherein, relative to The winding beginning portion of PVA based polymer films（Start PVA based polymer films being wound as film part during film roll）In it is above-mentioned Shortcoming A number, the winding ending portion of PVA based polymer films（Film portion at the end of PVA based polymer films are wound as into film roll Point）In disadvantages mentioned above A number be less than 1.4 times.In this film roll, due to the portion since the winding of PVA based polymer films Point until the difference of the surface characteristic of winding ending portion is small, thus according to the film roll, the light polarizing film of stay in grade can be manufactured And Polarizer.From such a viewpoint, relative to PVA based polymer films winding beginning portion disadvantages mentioned above A number Mesh, the disadvantages mentioned above A of the winding ending portion of PVA based polymer films number is preferably less than 1.3 times, more preferably 1.2 times Below, it is more preferably less than 1.1 times.In addition, in the film of the PVA based polymer films of strip, shortcoming A number generally has Have an increased tendency of time dependent, thus relative to PVA based polymer films winding beginning portion disadvantages mentioned above A number, PVA The disadvantages mentioned above A of the winding ending portion of based polymer film number is generally mostly more than 0.6 times, in addition, steady from manufacture quality The viewpoint such as fixed light polarizing film and Polarizer is set out, relative to the disadvantages mentioned above A of the winding beginning portions of PVA based polymer films Number, the disadvantages mentioned above A of the winding ending portion of PVA based polymer films number are preferably more than 0.7 times, are more preferably 0.75 Times more than, more preferably more than 0.8 times, be particularly preferably more than 0.9 times.

The film roll of the present invention（1）In PVA based polymer films in, A number does not limit especially the shortcomings that per unit area System, the PVA based polymer films as the present invention（1）The shortcomings that middle A number, if meeting above-mentioned number, i.e. if shortcoming A number Mesh is 0.25/m²Below（On the upper limit, preferably 0.20/m²Below, it is more preferably 0.15/m²Below, it is further excellent Elect 0.10/m as²Below, it is particularly preferably 0.075/m²Hereinafter, and on lower limit, preferably 0.001/m²Above, more Preferably 0.003/m²Above, more preferably 0.005/m²More than）, then, can be through length in continuously manufacture light polarizing film Time yield is good and stably manufacturing defect is few and meets the product of level of quality required in recent years, therefore it is preferred that.For The shortcomings that above-mentioned per unit area A number, as long as in the winding beginning portion of PVA based polymer films and winding ending portion Meet above-mentioned number in two parts, then it is believed that meeting the number in the PVA based polymer film entirety.

The film roll of the present invention（1）The length of the middle PVA based polymer films used（Spooling length）It is not particularly limited, can be with Purposes corresponding to PVA based polymer films etc. is suitably set, and specifically, it is more than 1000m that can make the length.However, in recent years Come in the manufacture of light polarizing film, in order to reduce with the trouble or the loss of time for changing film roll, it is sometimes desirable to 4000m than ever The longer PVA based polymer films of the length of left and right, even if using this longer PVA based polymers film through continuous manufacture for a long time Light polarizing film, the stay in grade of product can also be made, thus the length of PVA based polymer films is preferably more than 6000m, is more preferably More than 7000m, more preferably more than 8000m.The upper limit of the length of the PVA based polymer films of strip is not particularly limited, Weight or roll neck excessively become big etc. when film roll is being made as if long, and operability reduces, and keeping or transport have time-varying hardly possible, in addition, Also have be difficult to manufacture meet present invention provide that the tendency of film roll etc., therefore the length is preferably below 30000m, more preferably For below 25000m, more preferably below 20000m.It should illustrate, if the length is below 14000m, Jin Erwei Below 10000m, then be more prone to manufacture meet present invention provide that film roll.

As the film roll with the present invention（1）The related other compositions of the middle PVA based polymers film used, can be and conduct The PVA based polymer films of the present invention（1）The above identical of explanation form, thus the repetitive description thereof will be omitted here.

The film roll of the present invention（1）Be strip PVA based polymers film continuously winding form, for example, by the PVA systems of strip gather The core that compound film is continuously winding in cylindrical shape forms.During using the core for having cylindrical shape, the both ends of the core are preferably formed with from film The protuberance that the end face of volume protrudes.

The species of above-mentioned cylindric core is not particularly limited, and can enumerate for example, metal core, plastic core, paper The core of system, wooden core etc..Further, it is also possible to use：Using have metal and core both plastics, using have metal and paper this Both core, use the core for having the compound volume morphing such as plastics and the core both paper.Wherein, if considering intensity, durability, low hair Dirt etc., then preferred metal and/or plastic core, are also difficult to the angle by influences such as abrasions, more from reuse It is preferred that metal core.As above-mentioned metal, can enumerate for example, iron, stainless steel, aluminium etc., can be used alone 1 in them Kind, and two or more can also be used.In addition, as above-mentioned plastics, can enumerate for example, polyvinyl chloride, Vingon, polyester, poly- Carbonic ester, polyamide, epoxy resin, polyurethane, polyureas, organic siliconresin etc., it can be used alone 1 in them kind, also may be used And use two or more.In addition, from viewpoints such as intensity, the plastics can be the fiber-reinforced plastics such as carbon fiber reinforced plastic （FRP）.

［ PVA based polymer films（2）

The PVA based polymer films of the present invention（PVA based polymer films（2））, r.m.s. roughness is determined respectively on the two sides to film When, the differences of 2 r.m.s. roughnesses of gained is more than 0.3nm and below 10nm, less r.m.s. roughness be 10nm with Under.PVA based polymers film is continuously wound in the conventional film roll formed, and intermembranous sliding is bad etc. causes film easily to produce wrinkle Folding, and pass through the PVA based polymer films of the present invention（2）, the generation of the fold can be reduced.It should illustrate, the fold of film roll has： Wind PVA based polymer films caused by fold, with once after being made as film roll by its warehouse etc. certainly when because residuing in PVA systems The stress of polymer film and produce and tighten, due to the now intermembranous bad and caused fold of sliding；Pass through the PVA of the present invention Based polymer film（2）, the generation of the former fold can be effectively reduced, the generation of the latter's fold can also be reduced.In addition, According to the PVA based polymer films of the present invention（2）, can also easily manufacture what the dyeing inequality different from drawbacks described above was reduced Light polarizing film.

R.m.s. roughness in the present invention means JIS B0601：R.m.s. roughness described in 2001（Rq）, can lead to Cross in the roughness curve obtained from the surface of film, the deviation for being averaged line to roughness curve square carries out averagely coming Obtain.The r.m.s. roughness in each face on the two sides of PVA based polymer films can be determined by method described later in embodiment.

For the PVA based polymer films of the present invention（2）, when determining r.m.s. roughness respectively on the two sides to film, it is necessary to The difference of 2 r.m.s. roughnesses of gained is more than 0.3nm and below 10nm.It is more than 0.3nm, Ke Yiyou by both differences Effect ground reduces the generation of fold in film roll.On the other hand, it is below 10nm by both differences, light polarizing film can be effectively reduced In dyeing it is uneven.From such a viewpoint, both differences are preferably more than 0.5nm, more preferably more than 0.8nm, enter one Step is preferably more than 1.2nm, particularly preferably more than 1.5nm, is most preferably more than 2nm, furthermore it is preferred that being below 7nm, more excellent Elect below 5nm as.

In addition, the PVA based polymer films for the present invention（2）, it is necessary to less r.m.s. roughness is below 10nm.It is logical It is below 10nm to cross less r.m.s. roughness, and the dyeing that can be effectively reduced in light polarizing film is uneven.From such viewpoint Set out, less r.m.s. roughness is preferably below 8nm, more preferably below 6nm, more preferably below 4nm.Should Illustrate, in order that r.m.s. roughness extremely reduces and needs to apply special processing, easily make the manufacture of PVA based polymer films Cost increase, thus less r.m.s. roughness is preferably more than 0.3nm, more preferably more than 0.6nm, is more preferably More than 0.9nm, particularly preferably more than 1.2nm.

In PVA based polymer films（2）In, larger r.m.s. roughness is preferably more than 1nm and below 20nm.By compared with Big r.m.s. roughness is more than 1nm, can more effectively reduce the generation of fold in film roll.On the other hand, by larger R.m.s. roughness be below 20nm, it is uneven can more effectively to reduce dyeing in light polarizing film.From such a viewpoint, Larger r.m.s. roughness is more preferably more than 2nm, more preferably more than 4nm, in addition, more preferably below 15nm, More preferably below 11nm, particularly preferably below 8nm, it is most preferably below 6nm.

PVA based polymer films（2）Shape be not particularly limited, by the PVA based polymer films（2）As light polarizing film system In situation for the initial film made etc., from can productivity ratio well continuously manufacture light polarizing film grade, the preferably PVA of strip Based polymer film.

The length of the PVA based polymer films of the strip is not particularly limited, and can correspond to PVA based polymer films（2）'s Purposes etc. and suitably set, specifically, the length be preferably more than 1000m, more preferably more than 4000m, more preferably More than 6000m, particularly preferably more than 7000m, it is most preferably more than 8000m.Pass through such longer PVA based polymers Film, it can reduce with the trouble or the loss of time for changing film roll.The upper limit of the length of the PVA based polymer films of strip does not have Especially limitation, weight or roll neck excessively become big etc. when film roll is being made as if long, and operability reduces, and keeping or transport have time-varying Difficulty etc., thus the length is preferably below 30000m, more preferably below 25000m, more preferably below 20000m.Should One of explanation is given, the reason for as the fold occurred when preserving film roll, the stress institute for residuing in PVA based polymer films can be enumerated What is caused is tight, is easily consumingly embodied in longer wider PVA based polymer films because this is tight, thus in longer PVA Effect of the invention can be realized significantly more in based polymer film.

The width of the PVA based polymer films of strip is not particularly limited, such as can be more than 0.5m, due to needing in recent years Seek the light polarizing film of wide cut, therefore preferably more than 1m, more preferably more than 2m, more preferably more than 4m.The PVA systems of the strip The upper limit of the width of polymer film is not particularly limited, if the width is wide, light polarizing film is being manufactured with practical device In situation etc., there is the tendency for being difficult to equably be stretched, thus the width of PVA based polymer films is preferably below 7m.Should Explanation is given, it is identical with the explanation of the length to PVA based polymer films, due to tight easily in longer wider PVA based polymers Embodied strongly in film, thus effect of the invention in the broader PVA based polymers film of width can be realized significantly more.

PVA based polymer films（2）Thickness be not particularly limited, it is suitable to can correspond to purposes of PVA based polymer films etc. Preferably set, specifically, the thickness is preferably less than 300 μm, more preferably less than 150 μm, more preferably less than 100 μm. In addition, thinner light polarizing film is also required in recent years, from such viewpoint etc., PVA based polymer films（2）Thickness be preferably Less than 45 μm, more preferably less than 35 μm, more preferably less than 25 μm.PVA based polymer films（2）The lower limit of thickness do not have Have special limitation, from can more successfully manufacture light polarizing film in terms of grade, the thickness is preferably more than 3 μm, more preferably 5 More than μm.It should illustrate, the easier generation of fold in the more thin then film roll of thickness of PVA based polymer films, thus thinner Effect of the invention can be realized significantly more in PVA based polymer films.

As the PVA based polymer films with the present invention（2）Related other compositions, can be and the PVA as the present invention Based polymer film（1）The above identical of explanation form, thus the repetitive description thereof will be omitted here.

PVA based polymer films（2）Manufacture method be not particularly limited, according to aftermentioned PVA based polymer films of the invention Manufacture method, can easily manufacturing objective PVA based polymers film（2）, therefore it is preferred that.Now, with the surface of metal support The side of contact easily becomes the face with larger r.m.s. roughness.It should illustrate, in addition to the manufacture method, may be used also To consider：Manufacture PVA based polymers film is set to pass through the method between the different metallic roll of surface roughness；By PVA based polymer films Manufacture used in film stoste in foreign matter（Deteriorate resin or the pollution from outside etc.）Removed with filter etc., together When by the ultramicron of inorganic matter added in film stoste and the root mean square that is filmed on even surface and adjusts two sides is thick Method of rugosity etc..

［ film roll（2）

The film roll of the present invention（Film roll（2））It is as above-mentioned PVA based polymers film（2）Strip PVA based polymer films it is continuous Winding forms, for example, being using as PVA based polymer films（2）Strip PVA based polymer films be continuously winding in cylindrical shape Core forms.During using the core for having cylindrical shape, the both ends of the core are preferably formed with the protuberance from the end face of film roll protrusion.As The core, it can use and be used as film roll（1）Explanation and in those as described above, the repetitive description thereof will be omitted here.

For the film roll with the present invention（2）Relevant other compositions, can be and the film roll as the present invention（1）Explanation The above identical form, thus the repetitive description thereof will be omitted here.

The film roll of the present invention（2）In, the easily generation of caused fold when preserving film roll in the past can be reduced.As preservation Temperature during film roll, PVA based polymers film easily deforms and produces fold if too high, thus preferably less than 40 DEG C, More preferably less than 35 DEG C, more preferably less than 30 DEG C.On the other hand, the lower limit of temperature during preservation film roll is not special Limitation, the temperature are preferably more than -10 DEG C, more preferably more than -5 DEG C, more preferably more than 0 DEG C.

［ manufacture method of PVA based polymer films ］

Manufacture method of the invention for manufacturing PVA based polymer films has following processes：There is chromium coating, surface on surface Hardness is calculated as 550HV less than 900HV, surface temperature as more than 50 DEG C and less than 115 DEG C of metal branch using Vickers hardness Hold on the surface of body, the PVA based polymers of solution state or molten condition are cast and dried to be filmed.Then, Before the PVA based polymers of solution state or molten condition are started into curtain coating, the area on the surface of metal support（Breadth Maximum With the product of maximum end spacing）For 200 μm²The number of crackle above is 0.7/mm²Below., can according to the manufacture method Easily to manufacture the PVA based polymer films of the invention described above（PVA based polymer films（1）With（2））Or the film roll in the present invention （Film roll（1）With（2））In the PVA based polymer films of strip that continuously wind.

As the metal support used in the present invention, roller or band etc. can be enumerated, its surface has chromium coating.This In, the surface of metal support means the surface that the PVA based polymers of solution state or molten condition are cast（Film face）, gold In the case of belonging to support for roller, there can be chromium coating in the outer peripheral face of roller, can be in the continuous surface of band in the case of being band In lateral surface there is chromium coating.

The thickness of chromium coating is not particularly limited, and from the corrosion that can more efficiently prevent from metal support surface, and holds The number for easily reducing aftermentioned crackle is angularly set out, in the range of preferably more than 10 μm and 500 μm.It should illustrate, chromium coating It can once be formed, can also be formed several times, for example, when forming chromium coating several times, chromium coating can be initially formed temporarily Afterwards, the concavo-convex of its surface is removed by grinding etc., and is further forming chromium coating thereon.Carry out, then can reduce if so The pin hole of chromium coating.In addition, as described in the grade of patent document 4, when nickel coating is set under chromium coating, plating can be further reduced Crackle in layers of chrome.

Have on surface in the above-mentioned metal support of chromium coating, its case hardness is needed for 550HV with Vickers Less than 900HV.Metal support with common chromium coating is known（It see, for example, patent document 4~7 Deng）, when using such as the metal support with specific case hardness of the invention, though reason is not clear, it is logical The common processing implemented before the film of such as polishing grinding etc. starts to the surface of metal support is crossed, can easily reduce and deposit It is the number of the crackle on the surface of metal support, relatively can more reduces in the past above-mentioned in gained PVA based polymer films Shortcoming A number, and even if through manufacturing PVA based polymer films continuously for a long time, can also be by disadvantages mentioned above A number Change and be held in relatively in the past lower level.Furthermore, it is possible to the r.m.s. roughness on the two sides of film is adjusted to desired model Enclose.When above-mentioned case hardness is calculated as more than 900HV with Vickers hardness, it is difficult to reduce the crackle on the surface for being present in metal support Number, in addition, when through manufacturing PVA based polymer films continuously for a long time, the variation increase of disadvantages mentioned above A number.This Outside, the r.m.s. roughness on the two sides of film departs from desired scope.From as described above from the viewpoint of, above-mentioned case hardness with Vickers is preferably less than 800HV, more preferably less than 780HV.On the other hand, above-mentioned case hardness is with Vickers If being less than 550HV, the problem of easily producing in continuous film or cause damage etc. when cleaning the surface of metal support, The variation of disadvantages mentioned above A number also becomes big when through manufacturing PVA based polymer films continuously for a long time.In addition, the two sides of film R.m.s. roughness depart from desired scope.From such a viewpoint, above-mentioned case hardness is preferred with Vickers For more than 600HV, more preferably more than 650HV, more preferably more than 700HV.

The case hardness of metal support can determine the Vickers hardness of chromium plating layer surface by using hardometer etc. in many places And it is averaged and obtains.It should illustrate, the case hardness（Vickers hardness）Measure can be in solution state or molten condition The surface that is cast of PVA based polymers（Film face）Carry out, but because damage caused by measure may make gained PVA systems The quality of polymer film reduces, thus, even part formed with chromium coating etc. in the end of roller or band, solution state or The surface that the PVA based polymers of molten condition are cast（Film face）Nearby or the PVA systems of solution state or molten condition are poly- The surface that compound is cast（Film face）, can also be corresponding in the film part with cutting etc. and removing through ear after film Surface carries out the measure of case hardness, using its value as case hardness specified in the present invention.The case hardness of metal support It can specifically be obtained by method described later in embodiment.

Surface has the adjustment of the case hardness of the metal support of chromium coating in itself can be by known method easily Carry out, can specifically be carried out by following methods：The temperature of the chromium plating bath used during by chromium plating process is adjusted in specific scope Method；Current density during chromium plating process is adjusted to the method in specific scope；The method for adjusting the composition of chromium plating bath； Pass through heat treatment after chromium plating process（Annealing）Or adjust the method for hydrogen concentration of the occlusion in chromium coating exposed to hydrogen etc. Deng.Wherein, from etc. simple to operate, preferably the temperature of chromium plating bath is adjusted to the method in specific scope；Will Current density during chromium plating process is adjusted to the method in specific scope；Occlusion is adjusted after chromium plating process in chromium coating The method of hydrogen concentration, more preferably the temperature of chromium plating bath is adjusted to the method in specific scope.On the above method, will make Chromic acid-aqueous sulfuric acid of common chromium plating bath is used as, the scope for being more than 40 DEG C and less than 70 DEG C in the temperature of chromium plating bath Interior and current density is 60A/dm²When from the point of view of the situation of chromium plating process is carried out in following scope as an example, then with chromium plating The temperature of bath is higher and current density is lower, then case hardness generally gets over the tendency of step-down.In addition, on occlusion in chromium plating Hydrogen concentration in layer, then there is the temperature for improving heat treatment or extend processing time to make the reduction of its concentration, case hardness Generally get over the tendency of step-down.

As long as the forming method of above-mentioned chromium coating can form the metal support that case hardness meets above-mentioned scope Method be then not particularly limited, known method can be used, as the method for representative, illustration has：Metal is supported first The methods of surface of body is ground by polishing grinding or grinder is ground after strongly removing the bumps on surface, to be impregnated Degreasing, electrolytic degreasing, aqueous hydrochloric acid solution impregnating base treatment, chromium plating process then is carried out using chromium plating bath, and then carry out heat The method of processing.The representative of chromium plating bath is Sargent bath（サ ー ジ エ Application ト is bathed）, it can preferably be used.Sargent bath The example of the condition of composition and chromium plating process is as follows.

The composition ＞ of ＜ Sargents bath

Chromic anhybride：100~300g/L（Use the concentration of medicine benchmark）

Sulfuric acid：The 1/50~1/150 of used chromic anhybride（Mass ratio）.

The condition ＞ of ＜ chromium plating process

10~60A/dm of current density²

The temperature of chromium plating bath can largely effect on the case hardness of the metal support obtained as described above.As the specific of chromium plating bath Temperature, depending on heat treatment condition after the other conditions or chromium plating process employed in chromium plating process etc., but preferably 50 DEG C Above, more preferably more than 53 DEG C, more preferably more than 54 DEG C.The temperature of chromium plating bath gained metal support if too low Case hardness easily become too high.On the other hand, the temperature of chromium plating bath be preferably less than 66 DEG C, more preferably less than 63 DEG C, More preferably less than 61 DEG C, particularly preferably less than 58 DEG C.The metal support of the temperature of chromium plating bath gained if too high Case hardness easily become too low.

It is preferred that it is heat-treated after chromium plating process（Annealing）.When being heat-treated at high temperature, required for can shortening it Time, but temperature becomes easily to crack in chromium coating if too high, thus the temperature being heat-treated be preferably 130 DEG C with Under, more preferably less than 120 DEG C.On the contrary, when low temperature is heat-treated, although the risk that crackle occurs reduces, heat treatment The required time is elongated, thus the temperature being heat-treated is preferably more than 70 DEG C, more preferably more than 90 DEG C.The time of heat treatment Depending on the condition of chromium plating process or the temperature etc. of heat treatment, can be set in the range of 24~120 hours.

As solution state or the PVA based polymers of molten condition, can enumerate：It is situated between as PVA based polymers are dissolved in liquid The film stoste that matter forms or the film stoste containing PVA based polymers and liquid medium and the melting of PVA based polymers etc. are so The film stoste comprising PVA based polymers and liquid medium form person.The film stoste can further contain as needed Plasticizer, surfactant, other compositions as described above.

As the aforesaid liquid medium in film stoste, can enumerate for example：Water, dimethyl sulfoxide (DMSO), dimethylformamide, two Methylacetamide, 1-METHYLPYRROLIDONE, ethylene glycol, glycerine, propane diols, diethylene glycol (DEG), triethylene glycol, tetraethylene glycol, trihydroxy methyl third Alkane, ethylenediamine, diethylenetriamines etc., it can use one kind or two or more in them.Wherein, from the load to caused by environment From the viewpoint of small and recyclability, preferably water.That is, the preferred reality as solution state or the PVA based polymers of molten condition Example, the form of the film stoste containing PVA based polymers and water those can be enumerated.

It is film-made the volatile ingredient ratio of stoste（During film by volatilize, evaporate and the volatility such as the liquid medium that removes into Divide the content ratio in stoste is film-made）Different, preferably 50~90 matter depending on film-forming method, film forming condition etc. In the range of amount %, in the range of more preferably 55~80 mass %.By be film-made the volatile ingredient ratio of stoste for 50 mass % with On, being film-made the viscosity of stoste will not become too high, film stoste prepare when filtering, deaeration be smoothed out, foreign matter and lack The manufacture of the few PVA based polymer films of point becomes easy.On the other hand, it is 90 matter by being film-made the volatile ingredient ratio of stoste Below % is measured, being film-made the concentration of stoste will not become too low, and the manufacture of payable PVA based polymers film becomes easy.

The preparation method of above-mentioned film stoste is not particularly limited, and can enumerate for example：PVA based polymers are made to be dissolved in water etc. In liquid medium, and at least one kind of method being added as needed at this moment in plasticizer, surfactant, other compositions；Or The PVA based polymers of state containing liquid mediums such as water are subjected to melting mixing with extruder, and at this moment as needed one Play at least one kind of method in melting mixing plasticizer, surfactant, other compositions etc..

There are following processes in manufacture method of the invention for manufacturing PVA based polymer films：It is 50 in surface temperature More than DEG C and on the surface of less than 115 DEG C of above-mentioned metal support, the PVA systems of above-mentioned solution state or molten condition are polymerize Thing is cast and is dried and be filmed.If the surface temperature of metal support is more than 115 DEG C, gained PVA based polymers Shortcoming A number becomes more in film.In addition, the r.m.s. roughness on the two sides of film is easily separated from desired scope.According to the sight Point, the surface temperature of metal support is preferably less than 105 DEG C, more preferably less than 102 DEG C, be more preferably 99 DEG C with Under, particularly preferably less than 96 DEG C, most preferably less than 95 DEG C.On the other hand, if the surface temperature of metal support is less than 50 DEG C, then the problems such as being easily difficult to be damaged by the transparency of metal support stripping film or film.Go out from such viewpoint Hair, the surface temperature of metal support is preferably more than 60 DEG C, more preferably more than 70 DEG C, more preferably more than 80 DEG C. It should illustrate, as the surface temperature of metal support, any many places on the surface of metal support can be used（Such as 10 It is more than place）Surface temperature average value（Mean temperature）.

The surface temperature of metal support is set to be not particularly limited for the method in above range before film starts, example Such as, when using roller as metal support, can use：The thermal mediums such as water, oil, water vapour are passed through on the inside of roller, Or the sensing heating heater by being arranged at drum inside is heated, or by being set in a manner of relative with the surface of roller Method that the infrared heater or hot air heating apparatus put are heated etc..

On the ramp rates when making the surface temperature of metal support in above range before film starts, for example, As described in patent document 5, less than 3 DEG C/h can be set to, but using surface with chromium coating and with above-mentioned case hardness Metal support manufacture method of the invention in, although reason is failed to understand, it has been found that even if above-mentioned ramp rates are more carried Height, the rising of crackle number for being present in the surface of metal support can also be suppressed, even in cut down temperature settling tune with Make in the situation that productivity ratio improves, the disadvantages mentioned above A of the PVA based polymer films of gained number can also be controlled in low water It is flat.From such a viewpoint, the alternating temperature speed when making the surface temperature of metal support before film starts in above range Degree is preferably more than 0.5 DEG C/h, more preferably more than 1 DEG C/h, can also be set to more than 3.5 DEG C/h, 4 DEG C/h Above, more than 4.5 DEG C/h and then more than 5 DEG C/h.In addition, from the viewpoint of crackle number is reduced, above-mentioned alternating temperature speed Degree is preferably less than 10 DEG C/h, more preferably less than 7 DEG C/h.

In addition, when making the surface temperature of metal support before film starts in above range, from the sight for reducing crackle Point sets out, and preferably reduces the temperature difference of the width of metal support, specifically, continuously determines metal in the direction of the width The surface temperature of support, for the temperature profile data of gained, using the position of width as transverse axis, enter by the longitudinal axis of temperature During row mapping, the maximum of the absolute value of its slope is preferably 10 DEG C/below m, is more preferably 5 DEG C/below m, further preferably For 4 DEG C/below m, particularly preferably 3 DEG C/below m.

In addition, in manufacture method of the invention for manufacturing PVA based polymer films, by solution state or molten condition PVA based polymers start curtain coating before, the area on the surface of metal support is 200 μm²The number of crackle above is 0.7 Individual/mm²Below.Here, the area of crackle means the Breadth Maximum of crackle and the product of maximum end spacing.Generally, film is opened The surface of metal support before beginning there are the crackles such as the slight crack of chromium coating.Then, it is considered as buildup of resin in film The foreign matter of thing can gradually be attached to such crackle and form convex form, it is believed that be that the convex form is needed on film and formed on film Shortcoming A.Especially, PVA based polymers and other polymer phase ratios, hydrophily is high and has good compatibility with metal, because And it is considered as being easily accessible the crackle on the surface for being present in metal support and is used as the attachment of buildup of resin thing, it is believed that will be through dry Dry film from metal support peel off when etc. in, easily formed convex form and grown up.From it is such the reason for, in order to reduce Shortcoming A number, the number of the crackle on the surface for being present in metal support is preferably reduced as far as possible, if but as described above, making Metal support with surface with chromium coating and with above-mentioned case hardness, although reason is failed to understand, pass through such as polishing grinding Deng film start before metal support surface implement common processing, can easily reduce be present in metal support The number of the crackle on the surface of body, the disadvantages mentioned above A of gained PVA based polymer films number relatively can be more reduced in the past, and And even if through continuous manufacture PVA based polymer films for a long time, the variation of disadvantages mentioned above A number can also be held in more conventional Lower level.If the number of the crackle on the surface of metal support is more than 0.7/mm², then gained PVA based polymer films Middle shortcoming A number becomes more.From the viewpoint grade of the shortcomings that reducing gained PVA based polymer films A number, by solution shape Before the PVA based polymers of state or molten condition start curtain coating, the number of the above-mentioned crackle on the surface of metal support is preferably 0.3 Individual/mm²Below, it is more preferably 0.15/mm²Below.On the other hand, because extreme reduces the above-mentioned of the surface of metal support The number of crackle is more troublesome and effect is there is also the tendency to reach capacity, thus the number is preferably 0.005/mm²More than, More preferably 0.01/mm²More than.

The area on the surface of metal support is 200 μm²The number of crackle above can be obtained by following methods：In gold Belong to and being determined on the surface of support at arbitrary 25, be in 2mm × 2mm with microscope is specific respectively（4mm²）Scope " face Product is 200 μm²Crackle above ", obtains the 4mm²Scope × 25 at " area be 200 μm²The number of crackle above ", Every 1mm is calculated by the number²Number.Here, the area of crackle means the Breadth Maximum of each crackle and maximum end spacing Product, the maximum end spacing mean their end spacing when the end of crackle is only 2（Air line distance）, it is multiple ends Then mean the ultimate range in multiple end spacing during portion.Specifically, the area on the surface of metal support is 200 μm²More than The number of crackle can be obtained by method described later in embodiment.

The width of metal support can suitably be set according to the width of target PVA based polymer films.As metal branch The specific width of body is held, depending on the width of target PVA based polymer films, for example, more than 0.5m, and from effectively manufacturing From the viewpoint of the broad PVA based polymer film that wide cut light polarizing film can be manufactured, preferably more than 4.5m, more preferably 5.0m with Upper, more preferably more than 5.5m.If in addition, consider the cost of metal support or the easiness of maintenance etc., the metal The width of support is preferably below 7.5m, is preferably below 7.0m, more preferably below 6.5m.

The method that the PVA based polymers of solution state or molten condition are cast is not had on the surface of metal support There is special limitation, T-shaped slit die, hopper plate, I- moulds, lip type coating machine mould etc. can be used, method known to suppression is carried out.It should say Bright, the temperature of the PVA based polymers of molten condition or solution state is preferably in more than 50 DEG C and less than 105 DEG C of scope.

Drying after curtain coating can be carried out by known method, can be done by the heat assigned by metal support It is dry or carried out by blowing hot blast.Furthermore, it is possible to only by the drying on the surface of above-mentioned metal support to manufacture the phase The PVA based polymer films of prestige, it can also be carried out by known method etc. on the surface of above-mentioned metal support partially dried Afterwards, 1 or more than 2 to be parallel to each other by the downstream and the metal support that are configured at the metal support with rotary shaft Dryer roll or air drier be further dried to manufacture desired PVA based polymers film.

In so obtained PVA based polymers film, heat treatment can be implemented as needed or to width both ends（Ear Portion）Cut.Furthermore, it is possible to continuously winding is made as film roll as described above.

［ purposes ］

The PVA based polymer films of the present invention（PVA based polymer films（1）With（2））Or the film roll by the present invention（Film roll（1）With （2））The number that the PVA based polymers film rolled out can play shortcoming A is few；Stay in grade；Be difficult to produce fold the advantages that and by For various uses, from the viewpoint of effect of the present invention is significantly more realized, the light such as light polarizing film or phase retardation film are preferably used as Learn the initial film of film manufacture, the more preferably initial film as light polarizing film manufacture.

Above-mentioned PVA based polymers film is not particularly limited as initial film to manufacture the method for light polarizing film, can be adopted With known method, it is, for example, possible to use above-mentioned PVA based polymer films, dyed, be uniaxial tension, fixing process, dry Dry and as needed washing, heat treatment.Here, the order that dyeing, uniaxial tension, fixing process etc. are respectively handled is without spy Do not limit, one kind or two or more processing can be carried out simultaneously.In addition, one kind or two or more each processing can also be carried out 2 times Or more than 2 times, for example, uniaxial tension can be carried out 2 times or more than 2 times.Dyed, uniaxial tension, fixing process etc. Before each operation, swelling process can be carried out as needed.

Any stage when dyeing can be before uniaxial tension, uniaxial tension, after uniaxial tension is carried out.As used in dyeing Dyestuff, can be used it is following in it is one kind or two or more：Iodine-potassium iodide；Directly black 17,19,154；Direct brown 44,106,195, 210、223；Directly red 2,23,28,31,37,39,79,81,240,242,247；Directly indigo plant 1,15,22,78,90,98,151, 168、202、236、249、270；Directly purple 9,12,51,98；Direct green 1,85；Directly Huang 8,12,44,86,87；Direct orange 26, 39th, dichroic dyes such as 106,107 etc..Dyeing can by by PVA based polymers film immersion in the solution containing above-mentioned dyestuff（Dye Color is bathed）In come carry out.It should illustrate, above-mentioned dyestuff can be contained in advance when manufacturing PVA based polymer films.

Uniaxial tension can be carried out by any one of wet tensile method or xeothermic pulling method, can also be in warm water （Bathed including above-mentioned dye bath or fixing process described later）Carry out, the PVA based polymer films after water suction can also be used in air Middle progress.

Temperature when carrying out uniaxial tension is not particularly limited, and PVA based polymer films are carried out into uniaxial tension in warm water （Wet tensile）When, in preferably more than 30 DEG C and less than 90 DEG C of scope, and it is preferably then 50 DEG C when carrying out xeothermic stretching Above and in less than 180 DEG C of scope.

The stretching ratio of uniaxial tension（It is then the stretching ratio amounted to when carrying out uniaxial tension with multistage）, from polarizing properties From the viewpoint of, preferably more than 4 times, more preferably more than 5 times.The upper limit of stretching ratio is not particularly limited, if 8 times with Under then uniaxial tension readily and stably carry out, therefore it is preferred that.The thickness of film after uniaxial tension depends on PVA based polymers used The thickness of film, in preferably more than 3 μm and less than 75 μm of scope, in more preferably more than 5 μm and less than 50 μm of scope.

In order that absorption of the above-mentioned dyestuff to PVA based polymer films becomes firm, processing is fixed more.As bearing Fixing process bath used in reason, can be used and contain the one kind or two or more aqueous solution in the boron compounds such as boric acid, borax. Iodine compound can be added as needed in fixing process bath.

Dyed, after each processing such as uniaxial tension, fixing process, before drying, in order to will attach to film surface The processing body lotion respectively handled or foreign matter etc. remove, and are preferably washed.Cleaning solution used in washing can use pure water, be Suppress the outflow of the dyestuff or boron compound caused by washing, the water for being added with these medicaments on a small quantity can also be used.It can pass through Cleaning solution is sprayed to the surface of the film through each processing to carry out to spray etc., can also be by the way that the film immersion through each processing be existed Carried out in washing bath.

Dry, heat treatment carried out preferably more than 30 DEG C and in less than 150 DEG C of scope, more preferably more than 50 DEG C and Carried out in less than 150 DEG C of scope.

Using PVA based polymer films（2）Or by film roll（2）The PVA based polymer films rolled out are used as light polarizing film manufacture Initial film, and manufactured partially via each operations such as dyeing process, uniaxial tension process, fixing process process and drying processes In the situation of light film, the last processing bath before drying process is exited into（For example, fixing process bath or washing bath etc.）When, If make the liquid level that processing is bathed and film surface angulation（The angle of acute side）For more than 30 ° and less than 85 °, and make the upper of film The face of square side acts as the face in the PVA based polymer films of initial film with less r.m.s. roughness, then can be easy The light polarizing film of ground acquisition few foreign, therefore it is preferred that.

The reason for realizing the effect above is simultaneously indefinite, but is considered by manufacturing light polarizing film as described above, throughout reason bath The reason that the attachment of the treatment fluid used in the PVA based polymers of precipitation, each processing is reduced.Exiting into drying process During preceding last processing bath, handle that the liquid level of bath and film surface angulation are excessive or too small PVA systems that can make precipitation gather Compound or treatment fluid become easily attachment residual, thus the angle is preferably more than 35 °, is more preferably more than 40 °, further Preferably more than 50 °, furthermore it is preferred that being less than 80 °, more preferably less than 75 °, more preferably less than 70 °.

The light polarizing film obtained as described above generally in its two sides or single-sided lamination optical clear and has mechanical strength Diaphragm uses to be made as Polarizer.As diaphragm, cellulose triacetate can be used（TAC）Film, cellulose acetate-butyrate （CAB）Film, acrylic acid mesentery, polyester mesentery etc..In addition, as the bonding agent for being bonded, PVA systems bonding agent or poly- can be enumerated Urethane system bonding agent etc., wherein it is preferred that PVA systems bonding agent.

Embodiment

Hereinafter, the present invention is further illustrated by embodiment, but the present invention is not by their any restriction.It should say Bright, each measure or evaluation method employed in following preparation example, embodiment, reference example and comparative example are as follows.

［ measure of the case hardness of film roller ］

On the surface of film roller（Side face）, on the line for respectively enteing on the inside of 5mm from both ends, by the complete of film roller The mode of the deciles of Zhou Changdu 4 respectively determines at 4 points, altogether 8 points in each end.Then for each point, UCI formula hardometers MIC10 is passed through （GE セ Application シ Application グ ＆ イ Application ス ペ Network シ ョ Application テ Network ノ ロ ジ ー ズ Co. Ltd. systems；Probe uses MIC-2101-A）Survey Determine the Vickers hardness of chromium plating layer surface, the case hardness using their average value as film roller.

［ area on the surface of film roller is 200 μm²The measure of the number of crackle above ］

On the surface of film roller（Side face）It is upper to determine at arbitrary 25, for everywhere, using digital video microscopy VHX- 900（キ ー エ Application ス societies system）With 1000 times of multiplying power in 2mm × 2mm（4mm²）In the range of crackle（On chromium coating Slight crack）Photo taken pictures.Then, by μm in units of obtain on photo observed by each crackle Breadth Maximum with most Big end spacing（Then mean their end spacing when end is only 2, then mean in multiple end spacing most when being multiple Big distance）, and their product is calculated, it is 200 μm by the product²Crackle above is as " area is 200 μm²The above is split Line ".So carry out, in above-mentioned 4mm²Scope × 25 in obtain " area be 200 μm²The number of crackle above ", by the number Mesh calculates every 1mm²Number.

［ measure of the surface temperature of film roller ］

It is determined that the surface by film roller（Side face）On any 1 point of width 1 straight line and put down with 1 straight line Go and together with 1 straight line by other 3 straight lines of the decile of side face 4（I.e. so that every 1/4 weekly assembly of film roller is positioned at identical straight Straight line on line）, with Thermo Tracer TH9100MR（NEC Avio infrared ray テ Network ノ ロ ジ ー Co. Ltd. systems）Survey Temperature Distribution on fixed above-mentioned 4 straight line.Then, by gained temperature profile data, for each straight line, width central portion is obtained With from both ends towards each 3 points of central portion 20cm position（Amount at 12 points）Temperature, above-mentioned 12 points of temperature is averaging, Surface temperature using income value as film roller now.In addition, respectively by the temperature profile data system of each straight line of gained To be transverse axis and 4 curves using temperature as the longitudinal axis using the position of width, the maximum of the absolute value of its slope is obtained, will Its maximum temperature gradient as film roller now.

［ measure of the number of the shortcomings that PVA film ］

While PVA film is rolled out by film roll, while when being placed in fluorescent lamp thereafter by film observation, by the distortion of the image of fluorescent lamp It was found that the shortcomings that film, and oiliness magic ink circle will be used around it into circle.Then, with non-planar contact surfaces form measuring instrument “NewView”6300（ザ イ go society system）The shortcomings that observation is found, determines whether from film surface indentation and area（Opening Portion's area）For 400 μm²The shortcomings that above and depth is more than 0.3 μm（Shortcoming A）.Terminated by the winding in manufactured film roll Part（It should illustrate, in order to reduce error, except from the end of the length direction of film to 10m part）Start above-mentioned behaviour Make, obtain shortcoming A number be 10 when untill PVA film area（From start operation to the 10th shortcoming A length × film Width；Unit is m²）, by the area divided by 10（It is individual）, the shortcomings that thus calculating winding ending portion A number（Unit is Individual/m²）.In addition, among 10 shortcoming A, the length that same position and film are positioned essentially on the width of film is obtained The integral multiple of the interval in direction and the all-round length of the film roller used substantially has lacking for more than 2 of concord Point（Hereinafter, sometimes referred to as " swing circle shortcoming ".It should illustrate, this shortcoming also includes the part beyond the part for measure, It is believed that substantially with certain on the length direction of film（The integral multiple of the all-round length of film roller）Be spaced 3 More than）Number, by itself divided by above-mentioned area（Unit is m²）, thus calculate the number of the swing circle shortcoming of winding ending portion Mesh（Unit is individual/m²）.

Then, using remaining film roll, light polarizing film is manufactured as described later（Manufactured by the PVA film of winding ending portion side Light polarizing film）Afterwards, the film roll that the residual of unused state is in by most PVA film rolls out PVA film, and is rolled into new film again Volume, thus makes the winding beginning portion of initial film roll be located at the outside of new film roll.Using the new film roll carry out with it is above-mentioned Identical operates, the shortcomings that obtaining the winding beginning portion of initial film roll A and swing circle shortcoming number（Unit is Individual/m²）, light polarizing film is manufactured as described later using the film roll of residual（The light polarizing film manufactured by the PVA film of winding beginning portion side）.

［ evaluation of the fold of film roll ］

Film roll is observed by visual observation, passes through following benchmark evaluation fold.

A levels：Not it was observed that fold

B levels：Fold somewhat be present, but the level being had no problem in practicality

C levels：Deposit turns into the horizontal fold of problem in practical.

［ measure of the r.m.s. roughness of PVA film ］

Use white interference microscope NV6300（ザ イ go society system）The root mean square determined at any the 10 of the one side of PVA film is thick Rugosity, the r.m.s. roughness using their average value as the face.Then, identical behaviour is also carried out for the another side of PVA film Make, obtain r.m.s. roughness.

［ the evaluation of light polarizing film（20 experiments）

Heat treatment is dried by uniaxial tension fixing process is dyed according to pre- swelling by the PVA film that above-mentioned film roll rolls out Order is continuously handled, and makes light polarizing film.

That is, PVA film is impregnated 30 seconds in 30 DEG C of water, pre- swelling is carried out, then in iodine concentration 0.4g/L and iodate Potassium concn 40g/L 35 DEG C of aqueous solution（Dye bath）Middle dipping 3 minutes, is dyed.Then, in 50 DEG C of water of boric acid concentration 4% Solution（Stretch bath）In along its length with 5 times of stretching ratio progress uniaxial tensions, and then in iodate potassium concn 40g/L, boric acid Concentration 40g/L and zinc oxide concentration 10g/L 30 DEG C of aqueous solution（Fixing process is bathed）Middle dipping 5 minutes, is fixed processing.So Afterwards, film is subjected to heated-air drying at 40 DEG C, and then at 100 DEG C be heat-treated within 5 minutes.

From the arbitrary position of gained light polarizing film, take 50cm on length direction, on width 25cm test film 20 Piece.On the other hand, the few 50cm × 50cm of defect Polarizer is prepared, on the Polarizer, so that axis of orientation is vertical side The overlapping above-mentioned each test film of formula, it is placed on the lighting case of X-ray photographs observation（シャウカッセン）On, confirm each examination Test the defects of piece.It should illustrate, when not having defect in test film, overlapping Polarizer/test film is in completely black, and in test film When defective, then the bright defect of point-like can be identified as by the part light leak.It will be observed that the examination of more than the 2 bright defects Piece is tested as unqualified, calculates the qualification rate in 20 test films.

［ the evaluation of light polarizing film（100 experiments）

The number of test film is changed into 100 from 20, while will be observed that the test film of more than 1 bright defect as not It is qualified, in addition, carry out identically with above-mentioned 20 experiments, calculate the qualification rate in 100 test films.

［ the uneven evaluation with foreign matter of dyeing of light polarizing film ］

From the arbitrary position of gained light polarizing film take 50cm on length direction, on width 25cm test film.The opposing party Face, prepare uneven, few foreign the 50cm × 50cm of dyeing Polarizer, on the Polarizer, in a manner of axis of orientation is vertical Overlapping above-mentioned test film, is placed on the lighting case of X-ray photographs observation, according to the dye in following benchmark evaluation test film Color inequality and foreign matter.

Dyeing is uneven

A levels：Not it was observed that dyeing is uneven

B levels：It is uneven somewhat to there is dyeing, but the level being had no problem in practicality

C levels：Deposit uneven as the horizontal dyeing of problem in practical

Foreign matter

A levels：Not it was observed that foreign matter

B levels：Foreign matter somewhat be present, but the level being had no problem in practicality

C levels：Deposit turns into the horizontal foreign matter of problem in practical.

［ preparation example 1 ］

《The preparation of roller 1》

To the cylinder surface of the film roller of wide 1.0m carbon steel（Side face）It is polished and grinds and carry out ungrease treatment After base treatment, chromium plating process is implemented to the cylinder surface under the following conditions using chromium plating bath.It should illustrate, according to making With the concentration of medicine benchmark, above-mentioned medicine is dissolved in distilled water in a manner of chromic anhybride is 200g/L and sulfuric acid is 2g/L, made For chromium plating bath.

Chromium plating bath temperature：55℃

Current density：20A/dm²

Chromium coating thickness（After grinding）：50μm

Then, after chromium plating process terminates, the film is carried out being heat-treated for 50 hours with roller at 102 DEG C, let cool.

For by above-mentioned chromium plating process and heat treatment and on surface（Side face）The film roller of chromium coating is formd, according to Its case hardness is determined according to the above method, is as a result 760HV.Hereinafter, the film is referred to as " roller 1 " with roller.

［ preparation example 2 ］

《The preparation of roller 2》

Chromium plating bath temperature is changed into 52 DEG C, in addition, carries out chromium plating process and heat treatment identically with preparation example 1, is prepared Surface（Side face）Form the film roller of chromium coating.For the film roller, it is hard to determine its surface according to the above method Degree, is as a result 840HV.Hereinafter, the film is referred to as " roller 2 " with roller.

［ preparation example 3 ］

《The preparation of roller 3》

Chromium plating bath temperature is changed into 48 DEG C, in addition, carries out chromium plating process and heat treatment identically with preparation example 1, is prepared Surface（Side face）Form the film roller of chromium coating.For the film roller, it is hard to determine its surface according to the above method Degree, is as a result 950HV.Hereinafter, the film is referred to as " roller 3 " with roller.

［ preparation example 4 ］

《The preparation of roller 4》

Chromium plating bath temperature is changed into 67 DEG C, in addition, carries out chromium plating process and heat treatment identically with preparation example 1, is prepared Surface（Side face）Form the film roller of chromium coating.For the film roller, it is hard to determine its surface according to the above method Degree, is as a result 525HV.Hereinafter, the film is referred to as " roller 4 " with roller.

［ embodiment 1 ］

Roller 1 is installed on casting film equipment, and is connected with Warm water circulation device.Then, the side face of roller 1 is polished Grinding.The surface of the roller 1 after polishing grinding is determined by the above method（Side face）On area be 200 μm²Crackle above Number, be as a result 0.10/mm².Then, roller 1 is raised with 1 DEG C/h of ramp rates by Warm water circulation device Surface temperature, and maintain 90 DEG C of surface temperature.Maximum temperature gradient now is up to 3.8 DEG C/m.

On the other hand, by 99.9 moles of % of saponification degree, the PVA of the degree of polymerization 2400（The saponification of the homopolymer of vinyl acetate Thing）The mass parts of section 100 impregnated 24 hours in 35 DEG C of mass parts of distilled water 2500 after, carry out centrifugal dehydration, obtain PVA and contain Water is cut into slices.Volatile ingredient ratio in the aqueous sections of PVA is 70 mass %.Relative to the PVA 333 mass parts of aqueous section（With dry Dry state PVA conversions are calculated as 100 mass parts）, add the mass parts of glycerine 12 and surfactant（Contain lauric acid diethyl amide 95 mass %）After 0.3 mass parts, it is sufficiently mixed, is made as mixture, it is squeezed with the twin shaft with steam vent of 130 DEG C of maximum temperature Go out machine and carry out heating melting.After the PVA of gained molten condition is cooled into 100 DEG C with heat exchanger, by the wide rack-styles of 900mm Die head, it is adjusted to carry out extrusion film on 90 DEG C of foregoing roller 1 in surface temperature, and then is passed through in hot-air drying stove and is done It is dry, by width both ends（Ear）Cut, be thus continuously manufactured by the PVA film of wide 0.7m strip.It should illustrate, be film-made Speed is set to 8m/ points.By PVA film of the film after stable（60 μm of thickness, length 8000m）Continuously it is wound in 6 inches of diameter The cylindric core of aluminum and be made as film roll.

Film roll obtained by use, pass through the evaluation of the measure and light polarizing film of number the shortcomings that above method progress PVA film（20 Piece is tested）, as a result A number is 0.102/m the shortcomings that winding beginning portion²（Wherein, swing circle shortcoming be 0.031/ m²）, the qualification rate in 20 of light polarizing film experiments being manufactured by the PVA film of winding beginning portion side be 100%, winding end portion The shortcomings that dividing, A number was 0.098/m²（Wherein, swing circle shortcoming is 0.029/m²）, by winding beginning portion side Qualification rate in 20 experiments of the light polarizing film of PVA film manufacture is 100%.Relative to the number of A the shortcomings that winding beginning portion, The shortcomings that winding ending portion, A number was calculated as 0.96 times.

［ embodiment 2 ］

The length of PVA film is changed into 3000m from 8000m, in addition, carries out, is continuously manufactured by same as Example 1ly PVA film is simultaneously made as film roll.It should illustrate, the surface of the roller 1 after polishing grinding is determined by the above method（Side face）On face Product is 200 μm²The number of crackle above, is as a result 0.11/mm²。

Film roll obtained by use, pass through the evaluation of the measure and light polarizing film of number the shortcomings that above method progress PVA film（20 Piece is tested）, as a result A number is 0.110/m the shortcomings that winding beginning portion²（Wherein, swing circle shortcoming be 0.044/ m²）, the qualification rate in 20 of light polarizing film experiments being manufactured by the PVA film of winding beginning portion side be 100%, winding end portion The shortcomings that dividing, A number was 0.121/m²（Wherein, swing circle shortcoming is 0.036/m²）, by winding beginning portion side Qualification rate in 20 experiments of the light polarizing film of PVA film manufacture is 100%.Relative to the number of A the shortcomings that winding beginning portion, The shortcomings that winding ending portion, A number was calculated as 1.10 times.

［ reference example 1 ］

The length of PVA film is changed into 15000m from 8000m, in addition, carries out, is continuously manufactured by same as Example 1ly PVA film is simultaneously made as film roll.It should illustrate, the surface of the roller 1 after polishing grinding is determined by the above method（Side face）On face Product is 200 μm²The number of crackle above, is as a result 0.10/mm²。

Film roll obtained by use, by the measure of number the shortcomings that above method progress PVA film, as a result wind beginning portion The shortcomings that dividing, A number was 0.108/m²（Wherein, swing circle shortcoming is 0.032/m²）, winding ending portion the shortcomings that A Number be 0.160/m²（Wherein, swing circle shortcoming is 0.096/m²）.Relative to A the shortcomings that winding beginning portion Number, A number is calculated as 1.48 times the shortcomings that winding ending portion.

［ embodiment 3 ］

The PVA degree of polymerization is changed into 3300 from 2400, while the length of PVA film is changed into 15000m from 8000m, except this with Outside, carry out same as Example 1ly, be continuously manufactured by PVA film and be made as film roll.It should illustrate, be determined and thrown by the above method The surface of roller 1 after light grinding（Side face）On area be 200 μm²The number of crackle above, is as a result 0.10/mm²。

Film roll obtained by use, pass through the evaluation of the measure and light polarizing film of number the shortcomings that above method progress PVA film （100 experiments）, as a result A number is 0.088/m the shortcomings that winding beginning portion²（Wherein, swing circle shortcoming is 0.018/m²）, the qualification rate in 100 of light polarizing film experiments being manufactured by the PVA film of winding beginning portion side be 98%, volume The shortcomings that around latter end, A number was 0.118/m²（Wherein, swing circle shortcoming is 0.024/m²）, by winding Qualification rate in 100 experiments of the light polarizing film of the PVA film manufacture of part side is 95%.Relative to A the shortcomings that winding beginning portion Number, A number is calculated as 1.34 times the shortcomings that winding ending portion.

［ embodiment 4 ］

The PVA degree of polymerization is changed into 6000 from 2400, while the length of PVA film is changed into 15000m from 8000m, except this with Outside, carry out same as Example 1ly, be continuously manufactured by PVA film and be made as film roll.It should illustrate, be determined and thrown by the above method The surface of roller 1 after light grinding（Side face）On area be 200 μm²The number of crackle above, is as a result 0.13/mm²。

Film roll obtained by use, pass through the evaluation of the measure and light polarizing film of number the shortcomings that above method progress PVA film （100 experiments）, as a result A number is 0.067/m the shortcomings that winding beginning portion²（Wherein, swing circle shortcoming is 0.007/m²）, the qualification rate in 100 of light polarizing film experiments being manufactured by the PVA film of winding beginning portion side be 99%, volume The shortcomings that around latter end, A number was 0.074/m²（Wherein, swing circle shortcoming is 0.007/m²）, by winding Qualification rate in 100 experiments of the light polarizing film of the PVA film manufacture of part side is 99%.Relative to A the shortcomings that winding beginning portion Number, A number is calculated as 1.10 times the shortcomings that winding ending portion.

［ embodiment 5 ］

Roller 2 is used instead of roller 1, while the length of PVA film is changed into 3000m from 8000m, in addition, with implementation Example 1 is carried out in the same manner, is continuously manufactured by PVA film and is made as film roll.It should illustrate, after determining polishing grinding by the above method The surface of roller 2（Side face）On area be 200 μm²The number of crackle above, is as a result 0.39/mm²。

Film roll obtained by use, pass through the evaluation of the measure and light polarizing film of number the shortcomings that above method progress PVA film（20 Piece is tested）, as a result A number is 0.172/m the shortcomings that winding beginning portion²（Wherein, swing circle shortcoming be 0.052/ m²）, the qualification rate in 20 of light polarizing film experiments being manufactured by the PVA film of winding beginning portion side be 90%, winding ending portion The shortcomings that A number be 0.224/m²（Wherein, swing circle shortcoming is 0.134/m²）, by the PVA of winding beginning portion side Qualification rate in 20 experiments of the light polarizing film of film manufacture is 85%.Relative to the number of A the shortcomings that winding beginning portion, winding The shortcomings that latter end, A number was calculated as 1.30 times.

［ embodiment 6 ］

The surface temperature of roller 1 is changed into 110 DEG C from 90 DEG C, while the length of PVA film is changed into 3000m from 8000m, is removed Beyond this, carry out same as Example 1ly, be continuously manufactured by PVA film and be made as film roll.It should illustrate, be surveyed by the above method Determine the surface of the roller after polishing grinding 1（Side face）On area be 200 μm²More than crackle number, as a result for 0.13/ mm²。

Film roll obtained by use, pass through the evaluation of the measure and light polarizing film of number the shortcomings that above method progress PVA film（20 Piece is tested）, as a result A number is 0.132/m the shortcomings that winding beginning portion²（Wherein, swing circle shortcoming be 0.053/ m²）, the qualification rate in 20 of light polarizing film experiments being manufactured by the PVA film of winding beginning portion side be 95%, winding ending portion The shortcomings that A number be 0.180/m²（Wherein, swing circle shortcoming is 0.090/m²）, by the PVA of winding beginning portion side Qualification rate in 20 experiments of the light polarizing film of film manufacture is 90%.Relative to the number of A the shortcomings that winding beginning portion, winding The shortcomings that latter end, A number was calculated as 1.36 times.

［ embodiment 7 ］

Ramp rates are changed into 5 DEG C/h from 1 DEG C/h, in addition, carries out, continuously makes same as Example 1ly Make PVA film and be made as film roll.It should illustrate, the surface of the roller 1 after polishing grinding is determined by the above method（Side face）On Area is 200 μm²The number of crackle above, is as a result 0.10/mm²。

Film roll obtained by use, by the measure of number the shortcomings that above method progress PVA film, as a result wind beginning portion The shortcomings that dividing, A number was 0.110/m²（Wherein, swing circle shortcoming is 0.044/m²）, winding ending portion the shortcomings that A Number be 0.122/m²（Wherein, swing circle shortcoming is 0.049/m²）.Relative to A the shortcomings that winding beginning portion Number, A number is calculated as 1.11 times the shortcomings that winding ending portion.

［ comparative example 1 ］

Roller 3 is used instead of roller 1, in addition, is carried out same as Example 1ly, is continuously manufactured by PVA film and is made as film Volume.It should illustrate, the surface of the roller 3 after polishing grinding is determined by the above method（Side face）On area be 200 μm²More than Crackle number, be as a result 0.73/mm²。

Film roll obtained by use, pass through the evaluation of the measure and light polarizing film of number the shortcomings that above method progress PVA film（20 Piece is tested）, as a result A number is 0.291/m the shortcomings that winding beginning portion²（Wherein, swing circle shortcoming be 0.175/ m²）, the qualification rate in 20 of light polarizing film experiments being manufactured by the PVA film of winding beginning portion side be 80%, winding ending portion The shortcomings that A number be 0.938/m²（Wherein, swing circle shortcoming is 0.750/m²）, by the PVA of winding beginning portion side Qualification rate in 20 experiments of the light polarizing film of film manufacture is 50%.Relative to the number of A the shortcomings that winding beginning portion, winding The shortcomings that latter end, A number was calculated as 3.22 times.

［ comparative example 2 ］

The surface temperature of roller 1 is changed into 120 DEG C from 90 DEG C, while the length of PVA film is changed into 3000m from 8000m, is removed Beyond this, carry out same as Example 1ly, be continuously manufactured by PVA film and be made as film roll.It should illustrate, be surveyed by the above method Determine the surface of the roller after polishing grinding 1（Side face）On area be 200 μm²More than crackle number, as a result for 0.11/ mm²。

Film roll obtained by use, pass through the evaluation of the measure and light polarizing film of number the shortcomings that above method progress PVA film（20 Piece is tested）, as a result A number is 0.252/m the shortcomings that winding beginning portion²（Wherein, swing circle shortcoming be 0.101/ m²）, the qualification rate in 20 of light polarizing film experiments being manufactured by the PVA film of winding beginning portion side be 80%, winding ending portion The shortcomings that A number be 0.358/m²（Wherein, swing circle shortcoming is 0.251/m²）, by the PVA of winding beginning portion side Qualification rate in 20 experiments of the light polarizing film of film manufacture is 65%.Relative to the number of A the shortcomings that winding beginning portion, winding The shortcomings that latter end, A number was calculated as 1.42 times.

［ comparative example 3 ］

In embodiment 1, the surface temperature of roller 1 is changed into from 90 DEG C to 40 DEG C to attempt the manufacture of PVA film, but it is dry on roller It is dry insufficient and be difficult to by drum peel film, thus each evaluation is not carried out.

［ comparative example 4 ］

Ramp rates are changed into 5 DEG C/h from 1 DEG C/h, in addition, carries out, continuously makes identically with comparative example 1 Make PVA film and be made as film roll.It should illustrate, the surface of the roller 3 after polishing grinding is determined by the above method（Side face）On Area is 200 μm²The number of crackle above, is as a result 0.73/mm²。

Film roll obtained by use, by the measure of number the shortcomings that above method progress PVA film, as a result wind beginning portion The shortcomings that dividing, A number was 0.332/m²（Wherein, swing circle shortcoming is 0.166/m²）, winding ending portion the shortcomings that A Number be 1.349/m²（Wherein, swing circle shortcoming is 1.214/m²）.Relative to A the shortcomings that winding beginning portion Number, A number is calculated as 4.06 times the shortcomings that winding ending portion.

［ embodiment 8 ］

Roller 1 is installed on casting film equipment, and is connected with Warm water circulation device.Then, the side face of roller 1 is polished Grinding.The surface of the roller 1 after polishing grinding is determined by the above method（Side face）On area be 200 μm²Crackle above Number, be as a result 0.10/mm².Then, the surface temperature of roller 1 is raised by Warm water circulation device, and maintains surface 90 DEG C of temperature.

On the other hand, by 99.9 moles of % of saponification degree, the PVA of the degree of polymerization 2400（The saponification of the homopolymer of vinyl acetate Thing）The mass parts of section 100 impregnated 24 hours in 35 DEG C of mass parts of distilled water 2500 after, carry out centrifugal dehydration, obtain PVA and contain Water is cut into slices.Volatile ingredient ratio in the aqueous sections of PVA is 70 mass %.Relative to the PVA 333 mass parts of aqueous section（With dry Dry state PVA conversions are calculated as 100 mass parts）, add the mass parts of glycerine 12 and surfactant（Contain lauric acid diethyl amide 95 mass %）After 0.3 mass parts, it is sufficiently mixed, is made as mixture, it is squeezed with the twin shaft with steam vent of 130 DEG C of maximum temperature Go out machine and carry out heating melting.After the PVA of gained molten condition is cooled into 100 DEG C with heat exchanger, by the wide rack-styles of 900mm Die head, it is adjusted to carry out extrusion film on 90 DEG C of foregoing roller 1 in surface temperature, and then is passed through in hot-air drying stove and is done It is dry, by width both ends（Ear）Cut, be thus continuously manufactured by the PVA film of wide 0.7m strip.It should illustrate, be film-made Speed is set to 8m/ points.By PVA film of the film after stable（60 μm of thickness, length 12000m）Continuously it is wound in 6 inches of diameter The cylindric core of aluminum and be made as film roll.

The fold of film roll as obtained by above method evaluation（Wind fold caused by PVA film）, it is as a result A levels.In addition, Using the PVA film rolled out by gained film roll, the r.m.s. roughness of PVA film is determined by the above method, as a result with the table of roller 1 The be in contact r.m.s. roughness in face of side of face is 4.1nm, and the r.m.s. roughness of another side is 1.9nm.Both difference meters Calculate as 2.2nm.

By the PVA film that above-mentioned film roll rolls out the washing drying of fixing process uniaxial tension will be dyed according to pre- swelling Order continuously handled, make light polarizing film.That is, PVA film is impregnated 60 seconds in 30 DEG C of water, carries out pre- swelling, Then in iodine concentration 0.4g/L and iodate potassium concn 40g/L 35 DEG C of aqueous solution（Dye bath）Middle dipping 110 seconds, is contaminated Color.Then, in boric acid concentration 30g/L 30 DEG C of aqueous solution（Fixing process is bathed）Processing is fixed in 90 seconds in middle dipping, and then In 50 DEG C of aqueous solution of boric acid concentration 4%（Stretch bath）In along its length with 5 times of stretching ratio progress uniaxial tensions.Then, exist Boric acid concentration 15g/L 30 DEG C of aqueous solution（Washing bath）Middle dipping 10 seconds, is washed, and heated-air drying, system are carried out at 55 DEG C For light polarizing film.Should illustrate, by exit into the last processing bath before drying process i.e. washing bath when washing bath liquid level With film surface angulation, it is set as 60 ° by changing the position of deflector roll, while makes the face of the upper side of film now be institute There is the face of smaller r.m.s. roughness in the PVA film used.

The dyeing of light polarizing film is uneven as obtained by above method evaluation, is as a result A levels.In addition, evaluated by the above method The foreign matter of gained light polarizing film, it is as a result A levels.

［ embodiment 9 ］

Roller 2 is used instead of roller 1, in addition, is carried out same as Example 8ly, is continuously manufactured by PVA film and is made as film Volume.It should illustrate, the surface of the roller 2 after polishing grinding is determined by the above method（Side face）On area be 200 μm²More than Crackle number, be as a result 0.37/mm²。

The fold of film roll as obtained by above method evaluation（Wind fold caused by PVA film）, it is as a result B levels.In addition, Using the PVA film rolled out by gained film roll, the r.m.s. roughness of PVA film is determined by the above method, as a result with the table of roller 2 The be in contact r.m.s. roughness in face of side of face is 6.7nm, and the r.m.s. roughness of another side is 2.0nm.Both difference meters Calculate as 4.7nm.

For the PVA film rolled out by above-mentioned film roll, light polarizing film is made same as Example 8ly.Commented by the above method The dyeing of light polarizing film is uneven obtained by valency, is as a result B levels.In addition, as the above method evaluation obtained by light polarizing film foreign matter, as a result for B levels.

［ comparative example 5 ］

Roller 3 is used instead of roller 1, in addition, is carried out same as Example 8ly, is continuously manufactured by PVA film and is made as film Volume.It should illustrate, the surface of the roller 3 after polishing grinding is determined by the above method（Side face）On area be 200 μm²More than Crackle number, be as a result 0.73/mm²。

The fold of film roll as obtained by above method evaluation（Wind fold caused by PVA film）, it is as a result A levels.In addition, Using the PVA film rolled out by gained film roll, the r.m.s. roughness of PVA film is determined by the above method, as a result with the table of roller 3 The be in contact r.m.s. roughness in face of side of face is 28.3nm, and the r.m.s. roughness of another side is 2.6nm.Both difference meters Calculate as 25.7nm.

For the PVA film rolled out by above-mentioned film roll, light polarizing film is made same as Example 8ly.Commented by the above method The dyeing of light polarizing film is uneven obtained by valency, is as a result C levels.In addition, as the above method evaluation obtained by light polarizing film foreign matter, as a result for C levels.

［ comparative example 6 ］

Roller 4 is used instead of roller 1, in addition, is carried out same as Example 8ly, is continuously manufactured by PVA film and is made as film Volume.It should illustrate, the surface of the roller 4 after polishing grinding is determined by the above method（Side face）On area be 200 μm²More than Crackle number, be as a result 0.15/mm²。

The fold of film roll as obtained by above method evaluation（Wind fold caused by PVA film）, it is as a result C levels.In addition, Using the PVA film rolled out by gained film roll, the r.m.s. roughness of PVA film is determined by the above method, as a result with the table of roller 4 The be in contact r.m.s. roughness in face of side of face is 2.8nm, and the r.m.s. roughness of another side is 2.6nm.Both difference meters Calculate as 0.2nm.

For the PVA film rolled out by above-mentioned film roll, light polarizing film is made same as Example 8ly.Commented by the above method The dyeing of light polarizing film is uneven obtained by valency, is as a result A levels.In addition, as the above method evaluation obtained by light polarizing film foreign matter, as a result for A levels.

［ embodiment 10 ］

Using the film roll of gained in embodiment 8, the liquid level of washing bath when will leave washing bath is with film surface angulation from 60 ° 45 ° are changed into, in addition, makes light polarizing film same as Example 8ly.The dyeing of light polarizing film as obtained by above method evaluation Inequality, it is as a result A levels.In addition, as the above method evaluation obtained by light polarizing film foreign matter, be as a result B levels.

［ comparative example 7 ］

Using the film roll of gained in embodiment 8, used PVA film is changed into the face of the upper side of film when leaving washing bath In have larger r.m.s. roughness face, in addition, make light polarizing film same as Example 8ly.Commented by the above method The dyeing of light polarizing film is uneven obtained by valency, is as a result A levels.In addition, as the above method evaluation obtained by light polarizing film foreign matter, as a result for C levels.

［ comparative example 8 ］

Using the film roll of gained in embodiment 8, the liquid level of washing bath when will leave washing bath is with film surface angulation from 60 ° 25 ° are changed into, in addition, makes light polarizing film same as Example 8ly.The dyeing of light polarizing film as obtained by above method evaluation Inequality, it is as a result A levels.In addition, as the above method evaluation obtained by light polarizing film foreign matter, be as a result C levels.

［ comparative example 9 ］

Using the film roll of gained in embodiment 8, the liquid level of washing bath when will leave washing bath is with film surface angulation from 60 ° 88 ° are changed into, in addition, makes light polarizing film same as Example 8ly.The dyeing of light polarizing film as obtained by above method evaluation Inequality, it is as a result A levels.In addition, as the above method evaluation obtained by light polarizing film foreign matter, be as a result C levels.

Claims (12)

1. Polyvinyl alcohol film, wherein, when determining r.m.s. roughness respectively on the two sides to film, 2 of gained are The difference of root mean square roughness is more than 0.3nm and below 10nm, and less r.m.s. roughness is below 10nm.

2. the Polyvinyl alcohol film described in claim 1, wherein, larger r.m.s. roughness be more than 1nm and Below 20nm.

3. the Polyvinyl alcohol film described in claim 1, it is the Polyvinyl alcohol film of strip.

4. film roll, it is that continuously winding forms for Polyvinyl alcohol film described in claim 3.

5. system of the Polyvinyl alcohol film any one of usage right requirement 1~3 as the light polarizing film of initial film Method is made, this method has dyeing process, uniaxial tension process, fixing process process and drying process, exiting into drying When last processing before process is bathed, it is more than 30 ° and less than 85 ° to handle the liquid level of bath and film surface angulation, and film Upper side face be in Polyvinyl alcohol film have less r.m.s. roughness face.

6. light polarizing film, it is manufactured by the manufacture method described in claim 5.

7. the manufacture method of Polyvinyl alcohol film, it, which is included in surface, has chromium coating, case hardness with Vickers hardness 550HV is calculated as less than on the surface of 900HV, surface temperature for more than 50 DEG C and less than 115 DEG C of metal support, is incited somebody to action The process that solution state or the vinol series polymer of molten condition are cast and dried to be filmed；By solution shape Before the vinol series polymer of state or molten condition starts curtain coating, the area on the surface of metal support, i.e. Breadth Maximum with The product of maximum end spacing is 200 μm²The number of crackle above is 0.7/mm²Below.

8. the manufacture method described in claim 7, wherein, the vinol series polymer of solution state or molten condition be containing The form of the film stoste of vinol series polymer and water.

9. the manufacture method described in claim 7, wherein, the degree of polymerization of foregoing vinol series polymer for more than 3000 and Less than 10000.

10. the manufacture method described in claim 7, wherein, the case hardness of aforementioned metal support is calculated as with Vickers hardness 600HV is less than 800HV.

11. the manufacture method described in claim 7, it with more than 0.5 DEG C/h of ramp rates with making surface with chromium plating Layer, case hardness are calculated as surface temperatures of the 550HV less than 900HV metal support as more than 50 DEG C using Vickers hardness And less than 115 DEG C of process.

12. the manufacture method any one of claim 7~11, it is any one of manufacturing claims 1~3 The manufacture method of Polyvinyl alcohol film.