CN101258428A - Light diffusion film and surface light source using the same - Google Patents

Abstract

Disclosed is a light diffusion film comprising a base film which contains a light diffusion element inside. This light diffusion film is provided with a rough surface having a ratio between the maximum value Asmax and the minimum valum Asmin of the average aspect ratio, namely Asmax/Asmin (anisotropic degree) of not less than 1.1 on at least one side. This light diffusion film is excellent in luminance uniformity and high luminance characteristics.

Description

Light-diffusing film and the area source that uses it

Technical field

The present invention relates to be applied to suitably the area source (backlight) of LCD or light box, electricity light-diffusing film according to the flat light source of formula advertising board device, planar light etc.The more detailed point of saying relates to the light-diffusing film of the exit facet that can be applied to be installed in so-called positive following formula area source or side-light type area source suitably and uses positive following formula area source, the side-light type area source of this light-diffusing film.

Background technology

In the last few years, as the display device of personal computer, televisor or portable telephone etc., what One's name is legion ground used was the display that utilizes liquid crystal.These LCD owing to self be not luminophor, use the way of area source irradiates light to show so can adopt from the inboard.In addition, area source also will be tackled and must shine the requirement of picture integral body equably owing to not only wanted irradiates light, so what adopted is to be called the side-light type area source or the structure of the area source of following formula area source just.

At this moment, if in the emergent light of area source, exist luminance nonuniformity even, then owing to the image quality that can reduce display, so require to shine equably picture integral body.

Wherein, be applied to the area source of televisor etc., can use positive following formula area source suitably.So-called positive following formula area source is configured in light source in the hollow housing exactly, from the main plane outgoing of this housing flat light source (for example, with reference to patent documentation 1) from the mode of the emergent light of this light source.In other words, it is configured to, and the light source of a plurality of cold cathode ray tubes etc. is configured in the position of the positive bottom of light-emitting face.

For this reason, even if in all area sources in positive following formula area source, also exist in the picture top and be easy to produce big luminance difference in the position of the positive top that is equivalent to light source and the position of non-this position, be easy to be identified as the problem that luminance nonuniformity is spared.For this reason, in general will light-emitting face adopt have very strong optical diffuse translucent milky white plate (so-called light diffusing board) (Fig. 2), it is even to reduce luminance nonuniformity as much as possible.It is the plate of the resin of the acrylic acid of several mm or polycarbonate etc. that this light diffusing board uses the thickness of having sneaked into organic and inorganic particulate (it is desirable to the particulate of siloxane) etc.

In addition, even if people have also proposed under the above-mentioned situation still directly to print shading graph to light diffusing board under the situation of deficiency aspect the homogeneity, partly cover from the light of the top transmission of light source, make the scheme of the method (for example, with reference to patent documentation 2) etc. of the briliancy homogeneous of picture integral body.

On the other hand, under the demanding situation of picture briliancy of LCD etc.,, will adopt the gimmick of the light outgoing intensity etc. of further increasing light source for this situation.In this case,,, strengthen the optical diffuse of light diffusing board, attempting the elimination luminance nonuniformity and sparing so adopt the thickness of further thickening light diffusing board, further increase the way of the addition of particulate because it is even to be easier to produce luminance nonuniformity.

Patent documentation 1: the spy open flat 5-119311 communique (claim 1, Fig. 1)

Patent documentation 2: the spy opens flat 11-268211 communique (claim 1 and 2, Fig. 1 and Fig. 4)

But if only increase the optical diffuse of light diffusing board, then existing light transmittance will reduce, and has cut down the problem of the effect of improving because of the resulting briliancy of increase of the light outgoing intensity of light source.

Summary of the invention

So, the objective of the invention is in view of above each problem, it is even to provide efficient to eliminate luminance nonuniformity well, can take into account the briliancy uniformity coefficient on the picture and the new light-diffusing film of high briliancy characteristic.In addition, the present invention also aims to provide the new area source that has both high briliancy and high evenness that uses this light-diffusing film, particularly positive following formula area source.

The present invention, in order to address the above problem, take following formation, in other words, light-diffusing film of the present invention, have the matrix material film that contains light diffusing member in inside, and being formed with the maximal value Asmax of average asperratio and the ratio Asmax/Asmin of minimum value Asmin (each is to different degree) at least on a side surface is the concave-convex surface shape more than 1.1.

In addition, area source of the present invention is to use the area source of above-mentioned light-diffusing film.

If adopt light-diffusing film of the present invention, then can provide high positive briliancy characteristic and picture homogeneous degree is good, irradiating liquid crystal picture brightly, can be more distinct and be easy to watch the positive following formula area source of liquid crystal image.

Description of drawings

Fig. 1 is the stereographic map that is used for illustrating the structure of the area source that uses light-diffusing film of the present invention.

Fig. 2 is the stereographic map that is used for illustrating the structure of planar luminophor.

Fig. 3 is the figure that asks method of the concave-convex surface shape asperratio of explanation light-diffusing film.

Fig. 4 is the general view (removal light-diffusing film) that is used for illustrating the linearity configurations of light sources.

Fig. 5 is the general view (removal light-diffusing film) that is used for illustrating the linearity configurations of light sources.

Fig. 6 is the general view (removal light-diffusing film) that is used for illustrating the linearity configurations of light sources.

Fig. 7 is used for illustrating the mean distance of the light source of mean distance a, positive following formula area source between the light source of positive following formula area source and light-diffusing film and the sectional view of the relation of the angle θ that represents with formula (1).

Fig. 8 is the general view (removal light-diffusing film) that is used for illustrating the position relation of straight line L1～L10.

Fig. 9 is the general view that is used for illustrating the mensuration system of B (5), B (+5).

Figure 10 is (x-z) sectional view of the mould that uses in embodiment 3-1.

Figure 11 is (x-z) sectional view of the mould that uses in embodiment 3-2.

Figure 12 is (x-z) sectional view of the mould that uses in embodiment 3-3.

Label declaration

1: optical reflection film; 2: light source; 3: light diffusing board; 4: light projector; 5: incident ray; 6: light-receiving device; 7: light-diffusing film; 8: mould

Embodiment

Light-diffusing film of the present invention, necessary is: have the matrix material film that contains light diffusing member in inside, and formed the maximal value Asmax of average asperratio and the ratio Asmax/Asmin of minimum value Asmin (each is to different degree) at least on a side surface be the concave-convex surface shape more than 1.1.By forming the light-diffusing film that satisfies such condition, the luminance nonuniformity that just can improve positive following formula area source by leaps and bounds is even, just can improve the briliancy characteristic by leaps and bounds.

At first, light-diffusing film of the present invention must constitute with the matrix material film that light diffusing member be contained in inside.Though light also can only can not be made light diffusion fully with the concave-convex surface shape sometimes by fine concave-convex surface shape diffusion described later.So, adopt the way that contains light diffusing member in matrix material film inside, just can make optical efficiency diffusion better.

It is desirable to light diffusing member here, is made of the refractive index composition different with the principal ingredient that constitutes matrix material film.The difference of refractive index is big more, and then optical diffuse is just big more.

At first, in the present invention,, do not limit especially though constitute the resin of matrix material film,, it is desirable in the visible region, not have absorption.Said here " not having absorption in the visible region " only refers to two surfaces with 200 microns of these resins, thickness when constituting level and smooth film, and all light transmittances of this film are more than 70% in the whole field of 400nm～700nm.As the example of the resin that satisfies such condition, can use polyolefin (also comprising cyclenes copolymer etc.), polycarbonate or polyester etc. suitably.Wherein, as dimensional stability, mechanical property, the good resin of operability (processing), can use aromatic polyester suitably.

In aromatic polyester, desirable also be to use highly productive, polyethylene terephthalate (below, be called PET), poly-2,6-(ethylene naphthalate), PTT, polybutylene terephthalate, poly terephthalic acid 1,4-cyclohexane dimethyl ester etc.In addition, wherein, because PET resin cost is low and be easy to obtain, so can use suitably.

These polyester promptly can be homopolymer, also can be multipolymers.As being copolymer composition under the situation of multipolymer, can enumerate aromatic dicarboxylic acid, aliphatic dicarboxylic acid, alicyclic dicarboxylic acid, carbon number and be 2～15 diol component, as these examples, for example can enumerate m-phthalic acid, hexane diacid, decanedioic acid, phthalic acid, the m-phthalic acid that contains sulphonate-base and their ester formation property compound, diglycol, triethylene glycol, neopentyl glycol, cyclohexanedimethanol, poly alkylene glycol etc.

In the scope that does not influence effect of the present invention, also can in these vibrin, add various additives.As these additives, can enumerate fluorescer, crosslinking chemical, heat-resisting stabilizing agent, resistance to oxidation stabilizing agent, ultraviolet light absorber, the organically particulate, filling agent, photostabilizer, antistatic agent, nucleator, dyestuff, spreading agent, coupling agent etc. of lubricant, organic-inorganic.

Secondly, the kind of light diffusing member that is contained in the inside of the resin that constitutes film as described above limits especially, can use various inorganic particles, organic fine particles, resin etc.Light diffusing member it is desirable to do not have big absorption in the visible region.Light diffusing member both can be single component, also can use the composition more than 2 kinds.

Use in the principal ingredient that constitutes light-diffusing film under the situation of polyester based resin (refractive index 1.55～1.65), as can enumerating polyolefin-based resins (refractive index 1.45～1.55) suitably as the example of light diffusing member, siloxane-based resin (refractive index 1.4～1.5), acrylic resin (comprising interpolymer) (refractive index 1.45～1.55), metha crylic resin (comprising interpolymer) (refractive index 1.45～1.55), bubble (refractive index 1.0), silicon dioxide (refractive index 1.45～1.6), barium sulphate (refractive index 1.6～1.7), lime carbonate (refractive index 1.45～1.7) or titanium dioxide (refractive index 2.5～2.7) etc.

Wherein, the particulate that is made of siloxane-based resin, the particulate that is made of acrylic resin or the particulate that is made of the metha crylic resin etc. are considered and can be used suitably from refractive index with to the few aspect of visible absorption.Here, so-called particulate, the mean grain size that refers to as the mean value of ball equivalent diameter is more than 0.1 micron and the particulate below 100 microns.So-called ball equivalent diameter refers under the situation of the shape beyond particulate etc. has ball, has the diameter of the ball of the volume identical with its volume.

In addition, using as light diffusing member under the situation of polyolefin resin, polymethylpentene (refractive index 1.45) particularly, refractive index and to visible absorption few aspect see and can use suitably.In addition, because the fusing point of polymethylpentene is about 235 ℃, so also have the advantage that can melt extrude with polyester based resin.

Melt extruding the resin that constitutes matrix material film as mentioned above together and will become under the situation of resin of light diffusing member, the resin dispersion that will become light diffusing member is in the resin that constitutes matrix material film.The mean grain size of the light diffusing member under this situation can be tried to achieve the average way of ball equivalent diameter of dispersion that becomes the resin of light diffusing member by getting.

The mean grain size of light diffusing member it is desirable to more than 0.2 micron and below 50 microns, even more ideal is more than 0.3 micron and below 20 microns, again for it is desirable to more than 0.5 micron and below 10 microns.By the particle diameter that makes light diffusing member is in such scope, just can make light diffusion expeditiously, and it is even just can to reduce luminance nonuniformity.On the other hand, if be below 0.1 micron, owing to Rayleigh scattering phenomenon etc., transmission the light behind the film is coloured sometimes adheres to.In addition, if be more than 100 microns, then can see light diffusing member, be unfavorable from seeing in appearance.

In addition, above-mentioned refractive index is representational value, can change according to copolymer composition, the degree of polymerization, crystal structure etc.

In light-diffusing film of the present invention, it is desirable to more than 1% at light diffusing member area ratio/occupancy ratio perpendicular to the section of face, even more ideal is more than 2%.If the light diffusing member area ratio/occupancy ratio is more than 1%, then efficient is improved optical diffuse more well.

In addition, though upper limit not specially provided for,, if surpassed 50%, then optical diffuse will become excessive, incides the not only also scattering rearward forwards of light of film, so reduce light transmittance sometimes.

In light-diffusing film of the present invention, it is desirable to 250/mm perpendicular to the individual number density of the light diffusing member of the section of face ²More than.That even more ideal is 500/mm ²If the individual number density of light diffusing member is 250/mm ²More than, then efficient is improved optical diffuse better.

In addition, though the not specially provided for upper limit,, when having surpassed 100000000/mm ²The time, then optical diffuse will become excessive, incides the not only also scattering rearward forwards of light of film, so reduce light transmittance sometimes.

In addition, the light diffusing member occupation rate that it is desirable to the film section especially is more than 1% and the individual number density of the light diffusing member of film section it is desirable to 250/mm ²More than.In this case, will improve optical diffuse very expeditiously.

Light-diffusing film of the present invention it is desirable to, and the matrix material film that contains light diffusing member is by extending more than the single shaft.Even more ideal is to extend by twin shaft.This is because by matrix material film is extended, and light-diffusing film is whole just can to have the cause of the good mechanical property of high intensity etc.

Here, the method for the matrix material film after obtaining well extending as efficient for example can be enumerated the method for following such making stacked film.

At first, prepare to satisfy following formula (I) such thermoplastic resin A, B.

TA(℃)＞TB(℃) (I)

Here, TA is the fusing point of Resin A, and TB is the fusing point of resin B.The Resin A that fusing point is higher than resin B is laminated to the one-sided or both sides of resin B., light diffusing member is distributed in the resin B do not extended stacked here.

Then, press this stacked of the above extension of single shaft.At this moment, be accompanied by extension, produce at the interface of resin B and light diffusing member sometimes and peel off, produce the space that is called inner chamber.Under a spot of situation of being produced as of inner chamber, inner chamber self just becomes the light diffusing member for appropriateness.But under the situation that has produced a large amount of inner chambers, stacked transmissivity will reduce, and under situation about using as light-diffusing film, the briliancy characteristic is deterioration sometimes.Under these circumstances, after extension, adopt the way of under the condition that satisfies following formula (II), heat-treating, just can eliminate inner chamber.

TA(℃)＞TH(℃)＞TB(℃) (II)

Here, TH is a heat treatment temperature.In other words, adopt in resin B only and carry out the way of heat-treating under the temperature of fusion, just can eliminate the resin B of temporary transient generation and the inner chamber between the light diffusing member.

Handle the matrix material film after just can obtaining extending like that through above.

Here, though be not particularly limited as the resin kind that can be used as Resin A, resin B, but, as Resin A, can use polyethylene terephthalate suitably, as resin B, can use polyethylene terephthalate and m-phthalic acid or cyclohexanedimethanol etc. to carry out copolymerization suitably and make it eutectic and reveal the resin that forms.

In addition, though the qualification especially of at this moment spendable light diffusing member,, for example, can use previous described light diffusing member suitably.Use polyethylene terephthalate in Resin A; resin B uses polyethylene terephthalate and copolymerization such as m-phthalic acid or cyclohexanedimethanol, carried out eutectic reveals under the situation of the resin that forms, refractive index and on the point of the dispersiveness that resin carries out consideration can use the particulate that constitutes by siloxane-based resin especially suitably, the particulate that constitutes by acrylic resin, the particulate that constitutes by the metha crylic resin or the particulate that constitutes by polymethylpentene.

Secondly, light-diffusing film of the present invention also needs simultaneously: forming the maximal value Asmax of average asperratio and the ratio Asmax/Asmin of minimum value Asmin (each is to different degree) at least on a side surface is the concave-convex surface shape more than 1.1.

Below, at length surperficial concaveconvex shape is described.

At first, to not limit especially in the shape of the formed concave-convex surface in film surface in the present invention, but, for at least one side's surface, must form the maximal value Asmax of average asperratio and the ratio Asmax/Asmin of minimum value Asmin (each is to different degree) is the concave-convex surface shape more than 1.1.

Here, so-called average asperratio can as followsly be tried to achieve like that.

(1) so that film not avalanche ground on thickness direction vertically cuts off face, observes section., in the film section, the face direction is decided to be x direction of principal axis (direction arbitrarily is decided to be positive dirction) here, the thickness direction of film is decided to be the y direction of principal axis.

(2) among the protuberance of concave-convex surface shape (greatly place) arbitrarily 1 be decided to be A0 (referring to Fig. 3).

(3) then, on x axle positive dirction, nearest recess (the minimum place of thickness direction) is decided to be A1 for A0.

(4) absolute value of the axial distance of x of instrumentation A0 and A1 is decided to be Ax1 with it.At this moment, this distance less than 0.5 micron situation under, just this minimum place is not regarded as recess, on x axle positive dirction, seek next nearest recess, it is decided to be A1.

(5) absolute value of the axial distance of y of instrumentation A0 and A1 is decided to be Ay1 with it.At this moment, this distance less than 0.5 micron situation under, just this minimum place is not regarded as recess, on x axle positive dirction, seek next nearest recess, it is decided to be A1.

(6) ask As1 according to following formula.

As1＝Ay1/Ax1

(7) then, relative A1 is decided to be A2 for nearest protuberance (the very big place of thickness direction) on x axle positive dirction.

(8) absolute value of the axial distance of x of instrumentation A1 and A2 is decided to be Ax2 with it.At this moment, this distance less than 0.5 micron situation under, just this minimum place is not regarded as protuberance, on x axle positive dirction, seek next nearest protuberance, it is decided to be A2.

(9) absolute value of the axial distance of y of instrumentation A1 and A2 is decided to be Ay2 with it.At this moment, this distance less than 0.5 micron situation under, just this minimum place is not regarded as protuberance, on x axle positive dirction, seek next nearest protuberance, it is decided to be A2.

(10) ask As2 according to following formula.

As2＝Ay2/Ax2

(11) employing is carried out repeatedly from the way of the operation of above-mentioned (3)～(10), determines and the corresponding jog of A1～A100, asks As3～As100.

(12) ask the simple average of As1～As100, it is decided to be the asperratio As (0 °) of surface configuration.But, only arrive at jog under the situation of An, just ask the simple average of As1～Asn, it is decided to be the asperratio As (0 °) of concave-convex surface shape.Here n is the integer less than 100.

In addition, each of the asperratio in the face will be asked as described below to different degree.

(13) in face for the direction of in above-mentioned (1), being cut off, make become around clockwise direction depart from 15 ° direction like that relatively face vertically cut off.

(14) carry out the operation of above-mentioned (1)～(13), the asperratio of resulting surface configuration is decided to be As (15 °).

(15) similarly, in face for the direction of in above-mentioned (1), being cut off, make become around clockwise direction depart from 30 °, 45 °, 60 °, 75 °, 90 °, 105 °, 120 °, 135 °, 150 °, 165 ° direction like that relatively face vertically cut off film respectively, carry out the operation of above-mentioned (1)～(13), respectively the asperratio of resulting surface configuration be decided to be As (30 °), As (45 °), As (60 °), As (75 °) ..., As (165 °).

(16) As (0 °), As (15 °), As (30 °), As (45 °), As (60 °), As (75 °) ..., among the As (165 °), maximal value is made as Asmax, minimum value is made as Asmin.

(17) value (Asmax/Asmin) of removing the Asmax gained with Asmin is decided to be each to different degree.In addition, be under 0 the situation at Asmin, each just becomes to different degree and is infinity.In addition, any one in As (n °) (n=0～165 °) is under the situation of same value, and each just becomes to different degree is 1.

Light-diffusing film of the present invention, each of the concave-convex surface shape at least one side's surface is necessary for more than 1.1 to different degree.Each it is desirable to more than 1.3 to different degree, and even more ideal is more than 1.5, it is desirable to more than 2.0 especially.By what make the concave-convex surface shape is more than 1.1 to different degree respectively, just can obtain having the even light-diffusing film that improves effect and briliancy raising effect of high luminance nonuniformity.

By what make the concave-convex surface shape is more than 1.1 to different degree respectively, just can obtain the detailed reason of above-mentioned effect, though be unclear, the inventor etc. think be the reasons are as follows.

Particularly utilize the positive following formula area source of light-diffusing film of the present invention, as Fig. 4, Fig. 5 and shown in Figure 6, light source (for example, can enumerate cold-cathode tube, organic EL, inorganic EL, LED etc.) with line part, and its line part is set to parallel substantially more.

Under these circumstances, on the direction vertical with the line part of light source (for example, the direction that dots of Fig. 4), become to light source alternatively occurring and do not have the part of light source, briliancy distributes and has maximum deviation.

On the other hand, on the direction parallel, can obtain on (1) light source these 2 kinds of figures on (2) non-light source with the line part of light source.On (1) light source, (under) the situation, be the same substantially because the briliancy of light source distributes, for example, the direction of representing with single-point line of Fig. 4 at first so the deviation of briliancy distribution is little.Secondly (for example, the direction of representing with double dot dash line of Fig. 4 under) the situation, although owing to do not exist the absolute value of light source, briliancy low, the deviation that briliancy distributes is little on (2) non-light source.As mentioned above, the deviation of the briliancy of the direction parallel with the line part of light source distribution is little.In other words, the result just become for: from the emergent light of light source distribute (briliancy distributions) differ widely because of the direction of relative light source, promptly have big anisotropy.So,, do not need to make light diffusion, and, but need to make light diffusion very doughtily for the vertical direction of the rectilinear direction of relative light source for the parallel direction of the rectilinear direction of relative light source.

Be inferred to be formed at the film surface fine concavo-convex here, and have the light diffusing effect that makes.This optical diffuse, there is no need in whole is same degree.That is, for the vertical direction of the rectilinear direction of relative light source, though need make light diffusion strongly,, say for the direction that the rectilinear direction of relative light source is parallel, just there is no need to make light diffusion strongly.About the parallel direction of the rectilinear direction of relative light source, can think to it would be better to and do not make light diffusion strongly and briliancy is reduced.Therefore, as a result of, can efficient control radiation direction well, be considered to the briliancy characteristic and also can improve than existing light diffusing board with regard to becoming to the light-diffusing film of the application of the invention.

In addition, it is desirable to: for angle in the face of the maximal value Asmax of the asperratio that obtains the concave-convex surface shape, it is vertical in fact to obtain in the face of minimum value Asmin angle.This is considered to as mentioned above, must make the direction of light diffusion strongly in positive following formula area source, with the vertical cause of direction that also can not make it to carry out diffusion strongly.So-called here " vertical in fact " refer to scale be 15 ° the face of deciding what is right and what is wrong As (0 °), As (15 °) ..., among the As (165 °), the face of deciding what is right and what is wrong that becomes Asmax is vertical with the face of deciding what is right and what is wrong that becomes Asmin.For example, say be As (0 °) for Asmax As (90 °) for the situation of Asmin or As (105 °) for Asmax As (15 °) for the situation of Asmin etc.

In light-diffusing film of the present invention, it is desirable to form from the teeth outwards concavo-convex be fine.

Though this is because light-diffusing film of the present invention can be applied to LCD etc. suitably, but, because this display will be used eye-observation, so can see this situation of concave-convex surface shape of light-diffusing film, aspect the quality of LCD etc., most unfavorable cause.

For this reason, in the present invention, so-called fine, the simple average A xav that refers to the Ax1～Ax100 that is tried to achieve in the section that becomes Asmax is the situation below the 1mm.When Axav is 1mm when following, the concave-convex surface shape that just can prevent light-diffusing film is shown the device observer to be seen, just can provide high-grade display etc.

In addition, Axav it is desirable to below the 0.5mm, and even more ideal is below the 0.2mm.Though lower limit does not limit especially, be for more than 0.1 micron.By Axav is become is more than 0.1 micron, can make the light geometrical optics ground diffusion of the concaveconvex shape that is incident in the surface, just can efficient make light diffusion more well.

Have, in the present invention, it is desirable to Asmax is more than 0.3 again.Even more ideal is for more than 0.5, and it is desirable to especially is more than 0.7, and ideal is for more than 1.0.If Asmax is more than 0.3, then can obtain outstanding optical diffuse, can improve picture homogeneous degree, briliancy characteristic.In addition, though the upper limit does not have special provision,, it is desirable to is below 10.This is because if surpassed 10, and light only strengthens to the tendency of specific direction outgoing, is not beneficial to the cause of the briliancy homogenising in the picture sometimes very much.

In addition, as the concave-convex surface shape, being not particularly limited, both can be that regular shape also can be irregularly shaped.As the example of regular shape, can enumerate the part, whole etc. of quafric curve, trigonometric function.

In addition, be not particularly limited, can use hot stamping system, light to print suitably as the method that this fine concave-convex surface shape is formed at matrix material film.

So-called hot stamping system, heating has formed the mould and the resin of fine surface configuration exactly, and mould is pressed on the resin, behind cooling die and resin, makes mold releasability, will be in the gimmick of the shape transferred thereon that forms on the die surface to the resin., can be applicable to the resin of hot stamping system here, though both can be thermoplastic resin, also can be heat-curing resin,, it is desirable to the high resin of the transparency.As the resin of the hot stamping system of being applied to, can enumerate acrylic resin, siloxane-based resin, various cyclenes copolymer, polycarbonate, polystyrene, polyolefin, polyethylene terephthalate etc.When using polyethylene terephthalate,, it is desirable to make m-phthalic acid, cyclohexanedimethanol, naphthalate, the spiroglycol, fluorenes etc. to carry out copolymerization here, in order to reduce crystallinity.Because if the crystallinity height, then when hot stamping system, film is crystallization sometimes just, whitening.

On the other hand, so-called light is printed, exactly light-cured resin is coated on the matrix material film, the mould that has formed fine surface configuration is pressed to the part that is coated with light-cured resin, light to this part irradiation ultraviolet radiation etc., light-cured resin is solidified, and the demoulding then is in the gimmick of the shape transferred thereon that forms on the die surface to the resin.As the resin that is applicable to that light is printed, can enumerate acrylic resin.

The light transmittance of light-diffusing film of the present invention, it is desirable to is more than 40%.Even more ideal is for more than 50%, it is desirable to more than 60% especially.Because by making light transmittance is more than 40%, just can improve the briliancy characteristic.

The mist degree of light-diffusing film of the present invention it is desirable to more than 50%.Even more ideal is more than 65%, it is desirable to more than 80% especially.This is because if mist degree is more than 50%, then can improve the cause of the picture homogeneous degree under the situation that light-diffusing film is applied to area source.

The ideal thickness of the integral body of light-diffusing film of the present invention be below 1000 microns.Even more ideal is 10～500 microns, it is desirable to 20～300 microns especially.Here so-called " thickness of the integral body of light-diffusing film " only constituting under the situation of light-diffusing film with matrix material film, is exactly the thickness of this matrix material film.In addition, be under the situation of stacked other resin bed in matrix material film surface at light-diffusing film, be exactly matrix material film and resin bed thickness altogether.If whole thickness is below 1000 microns, then can make light-diffusing film lightweight, in addition, can also improve operability.By lightweight, when being loaded on the area source actually, also can reduce to be added in the loading of area source to light-diffusing film.Particularly under situation about integral thickness being become below 300 microns, light-diffusing film is rolled into the cylinder shape just becomes easily, can significantly improve operability and back processability.On the other hand, if surpassed 1000 microns, then be applied to as light-diffusing film under the situation of LCD etc., it is big that the thickness of area source integral body just becomes sometimes, is unfavorable.

So-called light-diffusing film as mentioned above, is assembled into the tabular component in the area source exactly in order to carry out light diffusion.Specifically, the light diffusing board that is used for positive following formula area source more.Therefore, say on the tone this point of picture that light-diffusing film it is desirable to approach netrual colour or bluer tone.Consider that this point an amount of interpolation fluorescer in light-diffusing film also is one of desirable form.Can suit to use the product of market sale as fluorescer, for example, カ ヤ ラ イ ト (R), リ ユ-コ プ ア (R) EGM that Network ラ イ ア Application ト ジ ヤ パ Application company produces etc. that produce of ケ イ コ-Le (R) of producing of the TBO that produces of the ユ PVC テ Star Network (R) produced of チ バ ガ イ ギ company, OB-1, the Sumitomo company that refines that イ-ス ト マ Application company produces, Japanese Cao Da company, Japanese chemical drug company.

In addition, light-diffusing film of the present invention it is desirable to: in relative film normal to a surface direction is in 20 °～50 ° the angular range during to this light-diffusing film incident ray, and making the minimum value BI to the relative briliancy of the light of normal direction transmission is more than 0.0014.Even more ideal is for more than 0.004, and it is desirable to especially is more than 0.008.

By the minimum value BI that makes relative briliancy is more than 0.0014, and the luminance nonuniformity that can improve positive following formula area source by leaps and bounds is even.

In addition, in light-diffusing film of the present invention, it is desirable to maximum average briliancy Bmax relatively is more than 0.002, and even more ideal is for more than 0.005, and it is desirable to especially is more than 0.01.

Here, relatively briliancy is to be used as the value that the determinator of goniophotometer is tried to achieve.Concrete assay method will be told about in the back, being that 20 °～50 ° angle is during to the light-diffusing film incident ray (establishing incident angle is θ) with relative light-diffusing film normal to a surface direction, remove and to be decided to be relative briliancy with cos θ except that this is worth resulting value again to the light intensity of normal direction transmission with the incident light intensity.In addition, pitch tilt (establishing the elevation angle is 0 °) not at this moment.

In addition, so-called average briliancy relatively, right exactly: as to ask average to the relative briliancy that with relative film normal to a surface direction is the light of 20 °～50 ° the angle normal direction transmission during to this light-diffusing film incident ray, so-called maximum average briliancy Bmax relatively, refer to behind the intra-face anisotropy of the surface of considering film and the back side and film, become the maximum average value of briliancy relatively.As for detailed assay method etc., will tell about in the back.

Minimum value BI by making relative briliancy and/or the maximum average value of briliancy Bmax relatively are in the above-mentioned scope, just can obtain having the even light-diffusing film that improves effect and briliancy raising effect of high luminance nonuniformity.In addition, though the minimum value BI of briliancy, the maximum average upper limit of briliancy Bmax relatively are not particularly limited relatively,, it is desirable to is below 0.5.Surpassing under 0.5 the situation, only the light of transmission specific direction makes even effect, the briliancy deterioration in characteristics improved of luminance nonuniformity on the contrary sometimes.

In addition, the minimum value BI of briliancy and/or maximum average briliancy Bmax relatively are in the light-diffusing film of the preferred configuration of the present invention in the above-mentioned scope relatively, can more be applied to especially ideally: the positive following formula area source with the linear light source portion more than two.Here, so-called linear light source portion more than two except that the situation of the light source that is arranged side by side a plurality of linearities shown in Figure 4, also comprises Fig. 5, shown in Figure 6 such by the line part such situation of formation more than 2 such as U letter shapes.A plurality of line parts in the light source it is desirable to become parallel.

Constitute under the situation of the line part more than 2 pressing U letter shapes etc., as long as line part is more than 2, even if a light source is also included within the light source portion with the line part more than 2.

Light-diffusing film of the present invention, be that 20 °～50 ° angle is to this light-diffusing film incident ray with relative film normal to a surface direction, film is carried out under the situation of rotation in the face, it is desirable to: to the maximum average ratio Bmax/Bmin of the relative briliancy Bmin of briliancy Bmax relatively of the light of normal direction transmission with minimum average B configuration be more than 1.1, even more ideal be for more than 1.3, it is desirable to especially is more than 1.5.If the Bmax/Bmin of light-diffusing film is more than 1.1, then can efficient make the interior briliancy homogenising of picture well, also can also obtain high briliancy characteristic.

Here, relative briliancy Bmin of minimum average B configuration and Bmax/Bmin will try to achieve with following method with goniophotometer.

Below, the average relative briliancy Bmin with minimum average B configuration of briliancy Bmax relatively of minimum value BI, maximum of relative briliancy and the method for asking of their ratio Bmax/Bmin are described in detail.

(1) mensuration is carried out with transmission measurement, and establishing the elevation angle is 0 ° (not pitch tilt), does not use Polarization filter, bandpass filter (color filter etc.).

(2) then, on sample stage, be not provided with whatever, angle of incidence of light θ is made as 0 °, acceptance angle is made as 0 °, and luminosity is measured, at this moment value is made as KA.

(3) two surfaces of determination object film are set at a face and b face for convenience's sake respectively.On sample stage, the determination object film is arranged so that plane of light incidence becomes a face, and there is not a bending etc., angle of incidence of light θ (to the face normal direction) is set at 20 °, acceptance angle is set at 0 ° (to face normal direction), measure luminosity KB (θ=20 °).

(4) ask relative briliancy B with following formula.

B(θ＝20°)＝(KB/KA)/cosθ

(5) similarly in θ=25 °, 30 °, 35 °, 40 °, 45 °, 50 ° ,-20 ° ,-25 ° ,-30 ° ,-35 ° ,-40 ° ,-45 ° ,-50 °, also ask relative briliancy.θ=20 °, 25 °, 30 °, 35 °, 40 °, 45 °, 50 ° ,-20 ° ,-25 ° ,-30 ° ,-35 ° ,-40 ° ,-45 ° ,-50 ° the minimum value of relative briliancy are made as BM (φ=0 °, a face).In addition, ask θ=20 °, 25 °, 30 °, 35 °, 40 °, 45 °, 50 ° ,-20 ° ,-25 ° ,-30 ° ,-35 ° ,-40 ° ,-45 ° ,-50 ° the average briliancy relatively of relative briliancy, it is made as Bav (φ=0 °, a face).Here, the face internal rotation angle degree (clockwise direction being decided to be+direction) during φ represents to measure.

(6) direction that film is measured in (3)～(5) relatively is transformed into 15 ° of sense of rotation around dextrorotation and rotates like that.Become in other words and be φ=15 °.

(7) carry out the operation of above-mentioned (3)～(5), obtain BM (φ=15 °, a face) and Bav (φ=15 °, a face).

(8) direction of being measured in (3) relatively in face becomes to rotating direction ground such after 30 °, 45 °, 60 °, 75 °, 90 °, 105 °, 120 °, 135 °, 150 °, 165 ° around making clockwise, and film is rotated in the face direction.Then, on position of rotation separately, carry out the operation of above-mentioned (3)～(5), obtain BM (φ=30 ° respectively, the a face), BM (φ=45 °, the a face) ..., BM (φ=165 °, a face) and Bav (φ=30 °, a face), Bav (φ=45 °, the a face) ..., Bav (φ=165 °, a face).

(9) also carry out the operation of above-mentioned (3)～(8) for the b face, obtain respectively BM (φ=0 °, b face), BM (φ=15 °, b face) ..., BM (φ=165 °, b face) and Bav (φ=-15 °, b face) ..., Bav (φ=-165 °, b face).

(10) with the highest value among the resulting Bav till above-mentioned (9) as the average briliancy Bmax relatively of maximum.In addition, the BM under the face when measuring Bmax and the angle φ is as the minimum value BI of relative briliancy.In the present invention, be under the situation of the concave-convex surface shape more than 1.1 to different degree only being formed with each on a side the surface, usually, the face of a side opposite with this face all becomes to obtaining the face of maximum average relative briliancy Bmax.

(11) in the face that obtains maximum average briliancy Bmax relatively, the value of the minimum among the resulting Bav in the said determination that makes face internal rotation angle φ variation as the relative briliancy Bmin of minimum average B configuration.

(12) ask the value (Bmax/Bmin) of removing Bmax with Bmin.In addition, be under 0 the situation at Bmin, Bmax/Bmin just will become and be infinity.In addition, be under the situation of same value at Bmax and Bmin, it is 1 that Bmax/Bmin just will become.

By making BI, Bmax, Bmax/Bmin is above-mentioned scope, can obtain the reason of above-mentioned effect, though unclear,, the inventor etc. think be the reasons are as follows.Light-diffusing film of the present invention, the positive following formula area source of being used suitably shown in Fig. 4～6, has the light source with the line part more than 2 more, and, be provided so that this line part becomes to parallel substantially.In other words, the result becomes to have big anisotropy in the emergent light from light source distributes.

Luminance nonuniformity is even, is because of from the different phenomenons that produce of the photodistributed big anisotropy of the outgoing of such light source owing to the briliancy between the briliancy of the positive top of light source and light source.If from the positive following formula area source of top view (if be that the direction of normal direction observe from the light-emitting area of opposite face light source), then, be very high briliancy so will become because the positive upper rim ray of light source is derived from body is luminophor.On the other hand, do not have luminophor in the nature of things between light source, the positive top of briliancy and light source is lower.Here, the briliancy between light source, mainly which kind of degree ground is to the refraction of observer's direction, scattering ground transmission actually to the light of light-diffusing film incident near the light source being present in, and it is important just to become.

For this reason, during to the light-diffusing film incident light, be positioned at the briliancy of the light-diffusing film of the part between light source, will rising owing to light quantity to the outgoing of face normal direction is become to more than a certain amount of with the angle of the δ that derives with following formula (III).As its result, it is believed that improve luminance nonuniformity even in, also demonstrate high briliancy characteristic.

Tanδ＝(a/2)/b (III)

In formula (III), a is a mean distance between the light source of positive following formula area source, and b is the light source of positive following formula area source and the mean distance of light reflection diffuser.Here, angle δ, what illustrate is angle shown in Figure 7 in other words.

In addition, in formula (III), a is a mean distance between the light source of positive following formula area source, followingly tries to achieve like that.

(1) long side direction of establishing area source is the L limit, and short side direction is the S limit.In addition, be under the foursquare situation at area source, be decided to be L limit and S limit aptly.Secondly, 11 five equilibriums are carried out on a side L limit, respectively straight line L1～L10 (Fig. 8) is vertically drawn on the L limit to the opposing party's L limit from Along ent.

(2) under the situation that straight line L1 and the fluorescent tube more than 2 intersect, measure from the intersection point (intersection point is decided to be the central part of fluorescent tube) of straight line L1 and initial fluorescent tube to the distance of the intersection point of next fluorescent tube (space between light sources from).Similarly handle and measure whole space between light sources from, calculate the average of them.If the average space between light sources of trying to achieve with this method is from being LA1.In addition, under the situation that straight line L1 only intersects with fluorescent tube below 1 since do not exist space between light sources from, so become to there not being data.

(3) for also carry out same operation from straight line L2 to L10, ask LA2～LA10.

(4) for the S limit, also straight line S1～S10 is vertically drawn to the S limit from Along ent respectively to the opposing party's S limit in 11 five equilibriums, one side's S limit.Then, carry out and the same operation in (2)～(3), ask SA1～SA11 and SA.

(5) mean distance between the light source that on average is taken as this area source of LA1～10 and SA1～10.In addition, as for the straight line that does not have data, just not as the object of average computation.

On the other hand, in above-mentioned formula (III), b is the mean distance of positive following formula area source and light-diffusing film, followingly tries to achieve like that.

(1) for simplicity, with linear light source portion 1, linear light source portion 2 ..., the such mode of the n of linear light source portion gives sequence number to each linear light source portion.

(2) length of the linear light source of instrumentation linear light source portion 1 part is carried out 11 five equilibriums to linear light source portion 1 in the longitudinal direction.

(3) for linear light source portion 1, the bee-line of instrumentation from the diametric central part of the linear light source portion of each Along ent to light source one side surface of light-diffusing film.

(4) the average bee-line of each Along ent, this mean value as distance between the linear light source portion-light-diffusing film of this linear light source portion.

(5) for other linear light source portion, also ask distance between linear light source portion-light-diffusing film.

(6) distance above resulting linear light source portion-light-diffusing film till from linear light source portion 1 to the n of linear light source portion is averaged, this mean value is made as b.

According to a and the b that try to achieve with above such method, with above-mentioned formula (III) derivation angle δ.

In addition, the δ of positive following formula area source that is applied to the LCD etc. of existing market sale mostly is 30 °～40 °.

Even in order to reduce luminance nonuniformity, it is desirable to: about the vertical direction of the rectilinear direction of relative light source, make light diffusion very doughtily, make that perhaps having certain ground such as directive property on the exit direction of light controls.Promptly, by utilizing the diffusion of light phenomenon, making on the exit direction of light, to have certain directive property etc., make to face with the light of angle δ incident and to eliminate from the photodistributed big anisotropy of the outgoing of light source to observer's frontal (normal direction of face) outgoing.Consequently be inferred to be and occur reducing that luminance nonuniformity is even, briliancy increases such effect.

By means of this, light-diffusing film of the present invention, it is desirable to have: make with the light of 20 °～50 ° angular range incident being equivalent to δ performance to the normal direction outgoing of face, specifically, it is desirable to: among the angle φ, the minimum value BI of briliancy is more than 0.0014 relatively in the highest face of directive property the highest in diffusive or emergent light.Promptly, we can say the minimum value BI of relative briliancy, be expression: in the highest face of directive property the highest in diffusive or emergent light among the angle φ, with to the light of the angular range incident of 20 °～50 ° of faces index to the lower limit of the performance of the normal direction outgoing of face.

Have again, maximum average briliancy Bmax relatively, can be described as expression: in the highest face of directive property the highest in diffusive or emergent light among the angle φ, with to the light of the angular range incident of 20 °～50 ° of faces average index to the performance of the normal direction outgoing of face.Maximum average briliancy Bmax relatively it is desirable to more than 0.002.

On the other hand, as for for the parallel direction of the rectilinear direction of light source, owing to be considered to not need to make light diffusion, so be speculated as film of the present invention in whole (in other words, in any φ) relatively minimum value BI, the maximum average value of briliancy Bmax relatively of briliancy, do not need height.Be considered to it would be better to and do not make light diffusion strongly and can not reduce briliancy.

So, light-diffusing film of the present invention, it is favourable being considered to have in face an optically anisotropic side, specifically, it is desirable to the maximum average ratio Bmax/Bmin of the relative briliancy Bmin with minimum average B configuration of briliancy Bmax relatively is more than 1.1.

As these result, light-diffusing film of the present invention, the result just becomes to efficient and controls exit direction into the light that shines well, be considered to reduce luminance nonuniformity even in, also improved with existing light-diffusing film comparison, briliancy characteristic.

According to the inventor's etc. discussion,, all may not obtain having the even light-diffusing film that improves effect of such luminance nonuniformity with existing any method.

Though the details of this reason are unclear,, be considered to because the purpose of existing light diffusing board only is to improve the cause of optical diffuse.For this reason, for the light-diffusing film purposes of purpose of the present invention, the even improvement of luminance nonuniformity is inadequate with regard to having to.

Because the LCD of market sale is used positive following formula area source mostly, so these LCD of dismounting, take out light diffusing board, measure relative briliancy, learn in angle of incidence of light θ is 20 °～50 ° scope, the minimum value BI of briliancy, maximum average relative briliancy Bmax are less than 0.0014 relatively, and Bmax/Bmin also is 1.0 substantially.

In addition, light-diffusing film of the present invention is that δ is the positive following formula area source of 10 °～60 ° scope, and can find even effect and the briliancy characteristic improved of high luminance nonuniformity.Even more ideal is 20 °～50 °.Ideal is 30 °～40 °.As δ during greater than 60 °, it is very big that the interval between light source just becomes, and is appropriate scope even if make relative briliancy BI, Bmax, Bmax/Bmin, and luminance nonuniformity is even also can not be eliminated sometimes fully.On the other hand, at δ during less than 10 °, briliancy characteristic deterioration sometimes then.

In addition, light-diffusing film of the present invention it is desirable to average briliancy B (+5) relatively and satisfy following formula (IV), or average briliancy B (5) relatively satisfies following formula (V).Even more ideal is satisfies formula (IV) and (V) this two side.Here, so-called average briliancy B (+5) relatively is exactly under the normal direction with relative face direction is 20 °～50 ° the situation of angle incident, to the average briliancy relatively that for normal direction is 5 ° direction transmission.In addition, so-called average briliancy B (5) relatively is exactly under the normal direction with relative face direction is 20 °～50 ° the situation of angle incident, to the average relative briliancy that for normal direction be-5 ° direction transmission.In addition, the mensuration of B (+5) and B (5) is that benchmark carries out with the condition determination of Bmax.In other words, at first, form to measure the condition of the value of Bmax, then, the light angle that makes light-receiving device departs from from the normal direction of film and is+5 ° or-5 ° (Fig. 9).But, the elevation angle is set at 0 ° (being set at not pitch tilt).

B(+5)/Bmax≥0.5 (IV)

B(-5)/Bmax≥0.5 (V)

Light-diffusing film of the present invention by satisfying formula (IV) or (V), further improves the even effect of improving of luminance nonuniformity.Though making great efforts now in the parsing as for the details of its reason, the inventor etc. think be the reasons are as follows.In other words, B (+5)/Bmax or B (5)/Bmax is little means for the incident ray with certain incident angle θ the light that outgoing directive property is strong.In other words, only refer to by a certain specific angle direction emergent ray strongly.Here, though light-diffusing film has the effect that makes the briliancy homogenising in the picture,, as prism only by a certain special angle direction strongly emergent ray be unfavorable.Because iff pressing a certain special angle direction emergent ray strongly, then the result just becomes to hardly by other direction emergent light, so the influence that hardly the briliancy homogenising in the picture is produced sometimes.

Here, becoming as the minimum value BI that is used for making relative briliancy is more than 0.0014, make maximum average briliancy Bmax relatively become means more than 0.0012, for example, the maximal value Asmax that can enumerate the asperratio of the surperficial micro concavo-convex shape that makes light-diffusing film is method more than 0.3 etc.What Asmax was even more ideal is more than 0.5, it is desirable to more than 0.7 especially.By making asperratio Asmax is more than 0.3, just can make the value of the minimum value BI of relative briliancy, relative briliancy Bmax bigger.In addition, though the upper limit of Asmax does not have special provision,, it is desirable to below 10.Because if surpassed 10, only the tendency to specific direction emergent ray will strengthen, B (+5)/Bmax, B (5)/Bmax reduces sometimes, is unfavorable for the briliancy homogenising in the picture sometimes.

In addition, light-diffusing film of the present invention, each is more than 1.1 to different degree Asmax/Asmin, because Asmax/Asmin is more than 1.1, so can make the value of Bmax/Bmin bigger.What Asmax/Asmin was even more ideal is more than 1.3, it is desirable to more than 1.5 especially.

Light-diffusing film of the present invention it is desirable to: contain in inside that to be formed with each on the surface of matrix material film of light diffusing member be concave-convex surface shape (below, be used as preferred configuration 1 of the present invention) more than 1.1 to different degree.Here, so-called " contain be formed with each on the surface of matrix material film of light diffusing member be concave-convex surface shape more than 1.1 " to different degree in inside, be exactly on the surface of matrix material film self, having formed each is the form of the concave-convex surface shape 1.1 or more to different degree, or to have formed on the overlay that is coated on the matrix material film be the form of the concave-convex surface shape more than 1.1 to different degree respectively.That is, in a film, contain light diffusing member, and formation is the form of the concave-convex surface shape more than 1.1 to different degree respectively.In other words, be not picture a film that contains light diffusing member in inside, be that the film of the concaveconvex shape more than 1.1 is piled up the form that such film different is piled up with having formed each from the teeth outwards to different degree.

The optical characteristics of light-diffusing film differs widely in preferred configuration 1 of the present invention with in the form of dividing other film to be piled up.Though making great efforts in the investigation as for the details of its reason,, the inventor etc. think be the reasons are as follows.

In other words, under situation about only film being piled up, between film and film owing to exist air layer, so during to the air layer transmitted ray, will have critical angle from the 1st film inside.Light with the above angle of this critical angle because total reflection phenomenon and can not transmission film and air layer between the interface, 100% is reflected.For this reason, the result just becomes to have the light of limited emergence angle from the 1st film, with limited light quantity outgoing.That is, only to the 2nd the limited emergent light of film incident.

On the other hand, in preferred configuration 1 of the present invention, then phenomenon as described above can not take place.At first, be under the situation of the concave-convex surface shape more than 1.1 having formed each on the surface of matrix material film self to different degree, natural there is not a critical angle, light transmittance increases.In addition, even if is under the situation of the concave-convex surface shape more than 1.1 having formed each on the overlay that is coated on the matrix material film to different degree, as long as still there is not critical angle in the refractive index of matrix material film less than the refractive index of the material that constitutes overlay, light transmittance still can increase.Even if the refractive index of matrix material film is greater than the refractive index of the material that constitutes overlay, this refringence, because also little than the refringence between matrix material film and the air, so the critical angle meeting becomes bigger, light transmittance still can increase.

That is, in preferred configuration 1 of the present invention, the result just become for: to the incident of concave-convex surface shape, the result is considered to can make more light carry out anisotropic diffusion by the concave-convex surface shape light of emergence angle with wide ranges with sufficient light quantity.Therefore, if with the light-diffusing film of preferred configuration 1 of the present invention, then has the realization easily that just becomes of these two effects of high briliancy characteristic and briliancy uniformity coefficient.

In addition, light-diffusing film of the present invention in the time of on being loaded into area source, it is desirable to be set to: make that be provided with each is that the face of the concave-convex surface shape more than 1.1 is positioned at observer's direction to different degree.By being loaded on the area source with this position relation, can significantly improve the interior briliancy of face of area source, also can improve briliancy uniformity coefficient in the face simultaneously.

In addition, in the area source that is mounted with light-diffusing film of the present invention, it is desirable to make between light-diffusing film and the light source have cloth and silk.

Here, so-called cloth and silk can be made of fiber.As the fiber that constitutes the light diffusion cloth and silk, the acrylic fibre that can comprise polymethylmethacrylate or polyacrylonitrile etc., polyethylene terephthalate, the dacron of polybutylene terephthalate etc., the polyamide fibre of nylon 6 or nylon 66 etc., polyurethane fiber, the polyolein fiber of tygon or polypropylene etc., polyimide fiber, polyacetal fibre, the polyethers fiber, styroflex, polycarbonate, polyesteramide fibre, polyphenylene sulfide fibre, polyvinyl chloride fibre, PEE, the polyvinyl acetate ester fiber, polyvinyl butyral fiber, poly-1,1-difluoroethylene fiber, the ethane-acetic acid ethyenyl ester copolymer fibre, any synthon of fluororesin series fiber and styrene-propene acid copolymer fibre etc., both can constitute, also can constitute by the synthon more than 2 kinds by a kind of synthon.From considerations such as sucting wet stability or thermal stabilitys, can use dacron or polyphenylene sulfide fibre, fluororesin series fiber etc. suitably.In addition, consider to use dacron suitably especially from the viewpoint of versatility, the transparency.

Above-mentioned fiber both can spin the spinning that obtains to the staple that has the length of crispaturaing, cutting into regulation, also can be the long filament that is made of continuous synthon.The bar number of the single thread that constitutes both can be 1 a mono filament, also can be the multiple long filament that is made of the single thread more than 2.Consider from the viewpoint of high light line transmissivity, it is desirable to use long filament.

In addition, though cloth and silk can be fabric, the cloth and silk of compiling any structure of thing, dry type nonwoven fabrics, Wet-laid non-woven fabric etc., but, good, the in uneven thickness also little and physical strength of the dimensional stability when cloth and silk is handled might as well viewpoint consider, it is desirable to fabric especially.The weave of fabric is not particularly limited, and can be any weave such as plain weave, twill-weave, satin weave.

Such cloth and silk is light weight in general, owing to himself have optical diffuse, so adopt the way that makes up with light-diffusing film, can further improve picture briliancy homogenising, high briliancyization.From the viewpoint, it is desirable to cloth and silk and have mist degree more than 50%.

In addition, launch such cloth and silk, be fixed in the area source housing,, also can make cloth and silk have the effect of conduct based on the support of the blooming of light-diffusing film by means of this.From the viewpoint, cloth and silk it is desirable to the good fabric of physical strength.

In addition, as cloth and silk, constitute the tone of the fiber of cloth and silk, it is desirable to colourlessly adhere to, netrual colour.Wherein, it is desirable to not have the Transparent color or the white of light absorption.By using the cloth and silk of these tones, just can reduce optical loss, help high briliancy characteristic.

In addition, above-mentioned cloth and silk is exposed to the ultraviolet ray that is contained in the light source during the light source igniting of the area source of LCD, sometimes can flavescence, strength deterioration takes place, and sometimes UV-durability is insufficient.After the cloth and silk flavescence, the tone of the light of the cloth and silk after the transmission flavescence sometimes can change, and the tone of display picture also can change.Therefore, it is desirable to above-mentioned cloth and silk and carried out the UV resistant processing.So-called UV resistant is handled, be exactly ultraviolet light absorber, antioxidant etc. (below, be called ultraviolet light absorber etc.) offer cloth and silk, even if make cloth and silk be exposed to the generation that also can reduce xanthochromia, strength deterioration in the ultraviolet ray, the method that provides, both can be the method for spraying ultraviolet light absorber etc. or carry out dry pad dyeing and handle the method that (pad cure) seasoning, coating process, print process etc. are provided to fiber surface after being impregnated into the body lotion of having put into ultraviolet light absorber etc. etc., also can be the method etc. that makes it to exhaust fibrous inside.

Secondly, the manufacture method explanation one example to light-diffusing film of the present invention still, is not limited to this example.

In having the compound film forming apparatus of main extruder and secondary extruder, supply with: carried out the small pieces (fusing point TB) of thermoplastic resin B of main stor(e)y of sufficient vacuum drying formation matrix material film and the potpourri that light diffusing member mixes as required to the main extruder that heated.The interpolation of light diffusing member both can use in advance fusion mixing equably to cooperate female small pieces (masterchip) of making, or directly carried out mixed grinding and supply to extruder etc.In addition, for stacked thermoplastic resin, supply to secondary extruder after the heating to the small pieces that carried out sufficient vacuum drying thermoplastic resin A as required with fusing point TA.

Like this raw material supplying to each extruder, in T mould composite die, make secondary extruder polymkeric substance on the one-sided face of the polymkeric substance of main extruder stacked like that (A/B or A/B/A), extrusion molding is a sheet together, obtains the melting layer lamination.

On cooled cylinder, be adjacent to this melting layer lamination of cooling immobilization, make and do not extend stacked film.At this moment, in order to obtain the film of homogeneous, it is desirable to add static and make it to be adjacent on the cylinder.Then, obtain matrix material film through extension process, heat treatment step etc. as required.

The special qualification of method nothing of extending has the extension method of twin shaft one by one of the extension that separates the extension of carrying out length direction and Width, twin shaft extension method when carrying out the extension of the extension of length direction and Width simultaneously.

As the method that twin shaft one by one extends, for example, the above-mentioned stacked film that do not extend is led toward the roller group that has heated, go up and extend at length direction (vertically, the direct of travel of film) in other words, follow, cool off with the cooled roller group.

Then, the limit is controlled the limit, two ends of the film that extends in the longitudinal direction it is led toward the stenter that has heated with pliers, just can extend on perpendicular to length direction (horizontal or Width).

Method as while twin shaft extension, for example, having the limit to control above-mentioned limit, two ends of not extending stacked film with pliers leads it toward the stenter that has heated, when extending on Width, adopt the way of accelerating the pliers translational speed, the method for carrying out the extension of length direction simultaneously.This is the twin shaft extension method simultaneously, owing to film can not contact with the roller after the heating, so have the advantage that can not be formed at the film surface as the scar of optical defective.

Have plane stability, dimensional stability in order to make resulting like this twin shaft extend stacked film, in addition, also eliminate the inner chamber (space) that between resin B and light diffusing member, produces as required, then, in stenter, heat-treat (heat fixation).Under the situation of eliminating inner chamber, it is desirable to make heat treatment temperature TA to become the temperature that satisfies above-mentioned formula (II) here.In addition, also can adopt the way of regulating heat treatment temperature, heat treatment time, fully eliminate inner chamber or make a part remaining get off also make it to play a role for inner chamber as light diffusing member.

After thermal treatment, after slowly cooling off equably, near the cool to room temperature, just can obtain matrix material film always.

Then, on matrix material film, apply light-cured resin with well-known coating means.After the coating, pushing formed asperratio each be the mould of concave-convex surface shape such more than 1.1 to different degree, irradiation light.Qualification that the direction of illumination of light has nothing special.After irradiation light, light-cured resin solidify, adopt the way of taking away mould, just can obtain light-diffusing film of the present invention.

Embodiment

Evaluation method to resulting light-diffusing film in each embodiment, comparative example, reference example describes.

[assay method of characteristic and evaluation method]

(1) the maximal value Asmax of the asperratio of concave-convex surface shape, minimum value Asmin, each is to different degree Asmax/Asmin

At first, use microtome, on thickness direction, do not make light-diffusing film avalanche ground that the face direction is vertically cut off light-diffusing film.Then, the scanning electron microscope of the S-2100A type of producing with (strain) Hitachi etc., amplify the section that observation post cuts off with suitable multiplying power (as for example 500～10000 times of targets roughly), according to previous described method, the maximal value Asmax of the asperratio of gauging surface concaveconvex shape, minimum value Asmin, each is to different degree Asmax/Asmin.In addition, for each embodiment, comparative example, reference example, the N number of the sample of mensuration is 1.

(2) light transmittance, mist degree

Direct-reading ヘ-ズ computing machine the HGM-2DP (illuminant-C is used) that produces with ス ガ testing machine (strain) measures light transmittance and mist degree.In addition, all light transmittance and mist degree will be asked for the two sides of light-diffusing film, light transmittance and the mist degree of the numerical value of the higher face of light transmittance as this light-diffusing film.In addition, for each embodiment, comparative example, reference example, the N number of the sample of mensuration is 1.

(3) perpendicular to the area ratio/occupancy ratio and the mean grain size of the light diffusing member of the section of face

At first, use microtome, light-diffusing film avalanche ground is vertically cut off the face direction.Then, the scanning electron microscope of the S-2100A type of producing with (strain) Hitachi etc., amplify the section that observation post cuts off with suitable multiplying power (as for example 500～10000 times of targets roughly), according to following method, calculate area ratio/occupancy ratio perpendicular to the light diffusing member in the section of face.In addition, for each embodiment, comparative example, reference example, the N number of the sample of mensuration is 1.

Measure the thickness of the integral body of film with amplifying the picture of observing, it is set at L.Then, in the film section, at random the scope of specific thickness direction L * face direction L is calculated the total area that is contained in the light diffusing member in this scope.Adopt with measurement range (L in other words ²) remove the way of the total area of this light diffusing member, calculate the area ratio/occupancy ratio of light diffusing member.Change measurement range and carry out same operation, the area ratio/occupancy ratio of mean value as the light diffusing member on the film section at 10 positions.

The method of asking as the area of single light diffusing member, be used in above-mentioned resulting profile image, in hyaline membrane or tracing paper, draw the shape of single light diffusing member, ask the area and the ball equivalent diameter of single light diffusing member with image analysis software (for example, (strain) Image Analyzer V10LAB twists flax fibers and weave in Japan, the NanoHunter NS2K-Lt that produces as the NANOSYSTEM (strain) of the follow-up software of above-mentioned software etc.).Here, the ball equivalent diameter is the area of the light diffusing member below 0.1 micron, is not included in the total area of light diffusing member.

In addition, simple average at the ball equivalent diameter of above-mentioned resulting each light diffusing member is as the mean grain size of light diffusing member.When asking the mean grain size of light diffusing member, comprise also that in average calculating the ball equivalent diameter is the light diffusing member below 0.1 micron here.

In addition, adopt the way of stacked film more than 2 layers to constitute, perhaps, under the situation that has formed overlay, the layer of only selecting to contain light diffusing member is observed.

(4) perpendicular to the individual number density of the light diffusing member of the section of face

At first, use microtome, light-diffusing film avalanche ground is vertically cut off face.Then, the scanning electron microscope of the S-2100A type of producing with (strain) Hitachi etc., amplify the section that observation post cuts off with suitable multiplying power (as for example 500～10000 times of targets roughly), calculate individual number density perpendicular to the light diffusing member of the section of face by means of following method.In addition, the N number of the sample of measuring for each embodiment, comparative example, reference example is 1.

Measure the thickness of the integral body of film with amplifying the picture of observing, it is set at L.Then, in the film section, at random the scope of specific thickness direction L * face direction L is calculated the number that is contained in the light diffusing member in this scope.Be light diffusing member below 0.1 micron here, make it to be not included in the number of light diffusing member for the ball equivalent diameter.Adopting with measurement range (is exactly L ²) remove the way of the number of this light diffusing member, calculate the individual number density of light diffusing member.Change measurement range and carry out same operation, the individual number density of mean value as the light diffusing member on the film section at 10 positions.Here, the unit of individual number density is [individual/mm ²].

In addition, constitute by stacked film more than 2 layers, when forming overlay, the layer of only selecting to contain light diffusing member is observed.

(5) positive briliancy of area source and uniformity coefficient

Use and be provided with the positive following formula area source of 12 length as the direct-line fluorescence pipe of the 4W of 39cm.Each fluorescent tube, parallel on the length direction of fluorescent tube, and be arranged so that between fluorescence that distance (fluorescent tube in the heart distance) becomes and be 26mm.The sectional thickness of fluorescent tube (diameter) is 2mm.In this positive following formula area source, the optical reflection film (eastern レ (strain) produces #188E60L) that is shaped as rectangle (long limit 40cm, minor face 30cm) is arranged so that in the bottom of fluorescent tube that distance between light source center portion and the reflecting plate bottom surface sections becomes is 10mm.

With this positive following formula area source, in embodiment 1-1～1-17,3-1～3-4 and comparative example 1-1～1-3,3-1, the light-diffusing film that is shaped as rectangle (long limit 40cm, minor face 30cm) being arranged so that distance between the surface of observer's direction of the center of fluorescent tube and light-diffusing film becomes is 10mm.In this case, the δ of area source is 52 °.

In embodiment 2-1～2-10, comparative example 2-1～2-4, reference example 2-1～2-3, the light-diffusing film that is shaped as rectangle (long limit 40cm, minor face 30cm) being arranged so that distance between the surface of observer's direction of the center of fluorescent tube and light-diffusing film becomes is 18.6mm.In this case, the δ of area source becomes 35 °.

No matter under any situation, the asperratio that also all is arranged so that light-diffusing film become for maximum direction vertical with the length direction of fluorescent light.

All fluorescent tubes are lighted, after having passed through 1 hour, carried out briliancy according to following method and measure.

The EyeScale-3 that briliancy is measured with (strain) Eyesystem carries out.In the position of the center of distance area source 1m, attached CCD camera is arranged so that for the area source face becomes the front.Here, the center of so-called area source refers to the focus point of the face of light-diffusing film.

The positive briliancy of area source is decided to be the average luminance of scope of the central portion 10cm * 10cm of area source.In this evaluation method, if the positive briliancy of area source is 5500cd/mm ²More than be exactly good.

In addition, uniformity coefficient adopts with minimum briliancy and tries to achieve except that the way of the maximum briliancy of the scope of the central portion 10cm * 10cm of area source.In addition, uniformity coefficient it is desirable to below 1.2, and even more ideal is below 1.1, and ideal is below 1.05.If this is because uniformity coefficient is big, then owing to the even cause that becomes sometimes to the picture that is unsuitable for watching of luminance nonuniformity.

In addition, for each embodiment, comparative example, reference example, the N number of the sample of being measured is 1.

(6) the minimum value BI of relative briliancy, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively

Briliancy is measured with automatic goniophotometer (goniophotometer) the GP-200 type that color technical institute in (strain) village produces relatively.Below, expression condition determination and assay method.In addition, for each embodiment, comparative example, reference example, the N number of the sample of being measured is 1.

(i) mensuration is carried out with transmission measurement, and the elevation angle is set at 0 ° (not pitch tilt), and the scale value VS1 of light beam diaphragm is set at 3.0, and the scale value VS3 that is subjected to the light diaphragm is set at 2.0.Do not use Polarization filter, bandpass filter (color filter etc.).

(ii) after having formed above-mentioned condition, angle of incidence of light θ is not set for 0 °, acceptance angle is set for 0 ° with on sample stage, not being provided with whatever, measure luminosity.At this moment, be adjusted to the knob of the HIGH VOLT ADJ. of body and make the demonstration of numerical value of panel table (output signal) become 90～110.At this moment the value of HIGH VOLT ADJ. is decided to be HVA, the numerical value of panel table (output signal) is decided to be KAA.In addition, even if at the knob of regulating HIGH VOLT ADJ., the demonstration of the numerical value of panel table (output signal) also surpasses under 110 the situation, will use the dim light wave filter.The dim light wave filter also can use more than 2.In addition, under the situation of using the dim light wave filter, measure light extinction rate GA in advance.The assay method of light extinction rate GA will be told about in the back.In addition, the dim light wave filter uses the dim light wave filter that the GP-200 type of color technical institute production in (strain) village is used.

Therefore, Shi Ji luminosity KA just will become for:

KA＝(KAA/GA)

(iii), for convenience's sake, be decided to be a face and b face respectively two surfaces of determination object film.On sample stage, the determination object film is arranged so that plane of light incidence becomes a face and do not have bending etc.If angle of incidence of light θ (to the face normal direction) is 20 °, acceptance angle is set at 0 ° (to face normal direction), measure luminosity KB (θ=20 °).

In addition, in mensuration, the value of establishing the HIGH VOLT ADJ. of body is HVA.In addition, surpassed under 110 the situation, will use the dim light wave filter in the demonstration of the numerical value of panel table (output signal).The dim light wave filter also can use more than 2.In addition, under the situation of using the dim light wave filter, measure light extinction rate GB in advance.The assay method of light extinction rate GB is based on the assay method of light extinction rate GA.Demonstration at the numerical value of panel table (output signal) surpasses under 110 the situation, just this numerical value is decided to be KBB.

Therefore, actual luminosity KB, just will become for:

KB＝(KBB/GB)

(iv), calculate the minimum value BI of relative briliancy, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively according to said method.

(assay method of light extinction rate GA)

Direct-reading ヘ-ズ computing machine the HGM-2DP (illuminant-C is used) that produces with ス ガ testing machine (strain) measures the straightaway light transmission, and establishing this measured value is GA.In addition, under the situation of using 2 above dim light wave filters, will under the state that the dim light wave filter is piled up, measure.The result who measures, resulting straightaway light transmission as light extinction rate.In addition, not using the light extinction rate under the situation of dim light wave filter is 1.00.

(7) the difference Δ φ of the face internal rotation angle of the maximum average briliancy Bmax relatively of expression and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration

Establishing the face internal rotation angle that is illustrated in the maximum average relative briliancy Bmax that is tried to achieve in (6) is φ max, when the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration is φ min, asks its difference Δ φ with following formula.

Δφ＝|φmax-φmin|

[embodiment, comparative example and reference example]

[embodiment 1-1]

Supply with to extruder: with the polycarbonate of 99.93 volume %, with the mixed sphere of anatase titanium dioxide of 1 micron of the mean grain size as light diffusing member (diameter) of 0.07 volume % as the main resinous principle that constitutes light-diffusing film.Then, melt extrude, apply method by means of static and on the casting cylinder of minute surface, cool off and be made into matrix material film.

Form concaveconvex shape with following method on a side surface at this matrix material film.In addition, here, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.0691×x)+5×sin(0.0628×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

At first, resulting matrix material film and mold heated to 180 ℃, kept 2 minutes.Then, the face that is formed with shape of mould is pressed to matrix material film, kept 3 minutes with the pressure of 10MPa.Then, keep-up pressure and be cooled to 130 ℃ unchangeably, pressure relief.Make the film demoulding that has formed the concave-convex surface shape by means of mould, obtain light-diffusing film.

The maximal value Asmax of the asperratio of the surface configuration of resulting light-diffusing film, minimum value Asmin, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.15, and average positive briliancy is 5800cd/m ², shown good performance.

[embodiment 1-2]

Supply with to extruder: as the main resinous principle that constitutes light-diffusing film, make the PET that the spiroglycol become ethylene glycol unit copolymerization 30mol (below, be called SPG-PET) with 99.2 volume %, as the polymethylpentene of light diffusing member with the mixed sphere of 0.8 volume %.Then, melt extrude, apply method by means of static and on the casting cylinder of minute surface, cool off and be made into matrix material film.

With with the same method of embodiment 1-1 at this matrix material film, form concaveconvex shape on a side surface.

Maximal value Asmax, the minimum value Asmin of the asperratio of the concave-convex surface shape of resulting light-diffusing film, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.In addition, polymethylpentene, the result that section is observed disperses spherically, and mean grain size (diameter) is 4 microns.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.10, and average positive briliancy is 5700cd/m ², shown good performance.

[embodiment 1-3]

Supply with to extruder: the SPG-PET of 98.8 volume %, the mixed sphere of the polymethylpentene as light diffusing member of 1.2 volume % as the main resinous principle that constitutes light-diffusing film.Then, melt extrude, apply method by means of static and on the casting cylinder of minute surface, cool off and make matrix material film.

With with the same method of embodiment 1-1 at this matrix material film, form concaveconvex shape on a side surface.

Maximal value Asmax, the minimum value Asmin of the asperratio of the concave-convex surface shape of resulting light-diffusing film, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.In addition, polymethylpentene, the result that section is observed disperses spherically, and mean grain size is 4.5 microns.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.08, and average positive briliancy is 5600cd/m ², shown good performance.

[embodiment 1-4]

Make m-phthalic acid for acid unit 10mol%, cyclohexanedimethanol and PET copolymerization for ethylene glycol unit 10mol% are got up, be made into vibrin (fusing point TB:225 ℃) (below, be called " IC-PET "), supply with to main extruder: as the above-mentioned vibrin of the main resinous principle that constitutes light-diffusing film with 97 volume %, the sphere that mixes with 3 volume % as the polymethylpentene of light diffusing member.In addition, use the secondary extruder different, supply with the sphere of PET (fusing point TA:265 ℃) to this pair extruder with main extruder.Then, carry out in the following manner that fusion 3 is folded layer by layer extrudes in the lump, this mode is: make top layer, both sides at the component layer that supplies to main extruder, supplied to the component layer of secondary extruder, pressed thickness ratio: the component layer of secondary extruder: the component layer of main extruder: the component layer of secondary extruder=ground was stacked in 1: 8: 1.Applying method by means of static makes the resin cooling of being extruded and makes 3 laminations layer by layer on the casting cylinder of minute surface.Make this stacked under 87 ℃ of temperature, to extend to 3.2 times in the longitudinal direction, then, on Width, extend to 3.4 times with 110 ℃ with the preheating zone of stenter by 95 ℃.Again heat treatment temperature TH is set at 235 ℃ and carries out thermal treatment in 30 seconds, obtain thickness thus and be 280 microns matrix material film.

Form concaveconvex shape at this matrix material film, on a side surface with following method.In addition, here, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.0691×x)+5×sin(0.0628×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

At first, with ultraviolet curable resin: (チ バ ス ペ シ ヤ Le テ イ ケ ミ カ Le ズ (strain) produces: (produce: ユ ニ デ イ Star Network 15-829) イ Le ガ キ ユ ア 907) to be mixed into ultraviolet curable resin by big Japanese ink chemical industry (strain) initiating agent for the quality ratio of initiating agent=99: 1, carry out mixing stirring in 30 minutes with stirring machine, obtain masking liquid.Then, for to make on the face that is formed with surface configuration of mould, the thickness of filming becomes 50 microns this masking liquid coating.After coating, the matrix material film mounting to the upper surface of filming, is made it to be adjacent to.Then from of the ultraviolet ray of matrix material face one side for die face direction irradiation total 500mJ/W.After the ultraviolet ray irradiation, under 40 ℃, carry out 30 minutes heat fixations.Then, adopt the way make mold releasability, obtain the ultraviolet curable resin layer that has formed the concave-convex surface shape is laminated to a side's of matrix material film the light-diffusing film of face.

Maximal value Asmax, the minimum value Asmin of the asperratio of the concave-convex surface shape of resulting light-diffusing film, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.In addition, polymethylpentene, the result that section is observed disperses spherically, and mean grain size (diameter) is 4.8 microns.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.06, and average positive briliancy is 5400cd/m ², shown good performance.

[embodiment 1-5]

To main extruder, supply with: with the IC-PET (fusing point TB:225 ℃) of 94 volume % as the main resinous principle that constitutes light-diffusing film, the sphere that mixes with the polymethylpentene of 6 volume % as light diffusing member.In addition, use the secondary extruder different, supply with the sphere of PET (fusing point TA:265 ℃) to this pair extruder with main extruder.Then, carry out in the following manner that fusion 3 is folded layer by layer extrudes in the lump, this mode is: make top layer, both sides at the component layer that supplies to main extruder, supplied to the component layer of secondary extruder, pressed thickness ratio: the component layer of secondary extruder: the component layer of main extruder: the component layer of secondary extruder=ground was stacked in 1: 8: 1.Applying method by means of static makes the resin cooling of being extruded and makes 3 laminations layer by layer on the casting cylinder of minute surface.Make this stacked under 87 ℃ of temperature, to extend to 3.2 times in the longitudinal direction, then, on Width, extend to 3.4 times with 110 ℃ with the preheating zone of stenter by 95 ℃.And then heat treatment temperature TH is set at 235 ℃ carries out thermal treatment in 30 seconds, obtain thickness thus and be 180 microns matrix material film.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.

Maximal value Asmax, the minimum value Asmin of the asperratio of the concave-convex surface shape of resulting light-diffusing film, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.In addition, polymethylpentene, the result that section is observed disperses spherically, and mean grain size (diameter) is 5 microns.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.05, and average positive briliancy is 5400cd/m ², shown good performance.

[embodiment 1-6]

Except the extrusion capacity that has changed main extruder and secondary extruder, use the matrix material film that obtains 120 microns of thickness with the same method of embodiment 1-5.In addition, the thickness ratio is the component layer of secondary extruder: the component layer of main extruder: the component layer of secondary extruder=1: 8: 1.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.104×x)+5×sin(0.0942×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

Maximal value Asmax, the minimum value Asmin of the asperratio of the concave-convex surface shape of resulting light-diffusing film, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.In addition, polymethylpentene, the result that section is observed disperses spherically, and mean grain size (diameter) is 5 microns.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.04, and average positive briliancy is 5500cd/m ², shown good performance.

[embodiment 1-7]

Except the extrusion capacity that has changed main extruder and secondary extruder, use the matrix material film that obtains 120 microns of thickness with the same method of embodiment 1-5.In addition, the thickness ratio is the component layer of secondary extruder: the component layer of main extruder: the component layer of secondary extruder=1: 8: 1.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.173×x)+5×sin(0.157×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

The maximal value Asmax of the asperratio of the surface configuration of resulting light-diffusing film, minimum value Asmin, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.In addition, polymethylpentene, the result that section is observed disperses spherically, and mean grain size (diameter) is 5 microns.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.03, and average positive briliancy is 5500cd/m ², shown good performance.

[embodiment 1-8]

Except the extrusion capacity that has changed main extruder and secondary extruder, use the matrix material film that obtains 120 microns of thickness with the same method of embodiment 1-5.In addition, the thickness ratio is the component layer of secondary extruder: the component layer of main extruder: the component layer of secondary extruder=1: 8: 1.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.346×x)+5×sin(0.314×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

The maximal value Asmax of the asperratio of the surface configuration of resulting light-diffusing film, minimum value Asmin, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.In addition, polymethylpentene, the result that section is observed disperses spherically, and mean grain size (diameter) is 5 microns.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.03, and average positive briliancy is 5500cd/m ², shown good performance.

[embodiment 1-9]

Except the extrusion capacity that has changed main extruder and secondary extruder, use the matrix material film that obtains 120 microns of thickness with the same method of embodiment 1-5.In addition, the thickness ratio is the component layer of secondary extruder: the component layer of main extruder: the component layer of secondary extruder=1: 8: 1.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.518×x)+5×sin(0.471×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

Maximal value Asmax, the minimum value Asmin of the asperratio of the concave-convex surface shape of resulting light-diffusing film, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.In addition, polymethylpentene, the result that section is observed disperses spherically, and mean grain size (diameter) is 5 microns.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.03, and average positive briliancy is 5600cd/m ², shown good performance.

[embodiment 1-10]

Except the extrusion capacity that has changed main extruder and secondary extruder, use the matrix material film that obtains 120 microns of thickness with the same method of embodiment 1-5.In addition, the thickness ratio is the component layer of secondary extruder: the component layer of main extruder: the component layer of secondary extruder=1: 8: 1.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.0942×x)+5×sin(0.0628×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

Maximal value Asmax, the minimum value Asmin of the asperratio of the concave-convex surface shape of resulting light-diffusing film, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.In addition, polymethylpentene, the result that section is observed disperses spherically, and mean grain size (diameter) is 5 microns.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.02, and average positive briliancy is 5500cd/m ², shown good performance.

[embodiment 1-11]

Except the extrusion capacity that has changed main extruder and secondary extruder, use the matrix material film that obtains 120 microns of thickness with the same method of embodiment 1-5.In addition, the thickness ratio is the component layer of secondary extruder: the component layer of main extruder: the component layer of secondary extruder=1: 8: 1.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.0942×x)+5×sin(0.0471×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

The maximal value Asmax of the asperratio of the surface configuration of resulting light-diffusing film, minimum value Asmin, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.In addition, polymethylpentene, the result that section is observed disperses spherically, and mean grain size (diameter) is 5 microns.

This light-diffusing film laid to making the face formed the concave-convex surface shape become be observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.01, and average positive briliancy is 5500cd/m ², shown good performance.

[embodiment 1-12]

To main extruder, supply with: making IC-PET (fusing point TB:225 ℃) as the main resinous principle that constitutes light-diffusing film with 96 volume %, is the sphere that 4 microns the crosslinked particulate of acrylic acid-polystyrene mixes with 4 volume % as the mean grain size of light diffusing member.In addition, use the secondary extruder different, supply with the sphere of PET (fusing point TA:265 ℃) to this pair extruder with main extruder.Then, carry out in the following manner that fusion 3 is folded layer by layer extrudes in the lump, this mode is: make top layer, both sides at the component layer that supplies to main extruder, supplied to the component layer of secondary extruder, pressed thickness ratio: the component layer of secondary extruder: the component layer of main extruder: the component layer of secondary extruder=ground was stacked in 1: 8: 1.Applying method by means of static makes the resin cooling of being extruded and makes 3 laminations layer by layer on the casting cylinder of minute surface.Make this stacked under 87 ℃ of temperature, to extend to 3.2 times in the longitudinal direction, then, with stenter by 95 ℃ the preheating zone and on Width, extend to 3.4 times with 110 ℃.And then heat treatment temperature TH is set at 235 ℃ carries out thermal treatment in 30 seconds, obtain the matrix material film of 120 microns of thickness thus.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.0942×x)+5×sin(0.0314×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

Maximal value Asmax, the minimum value Asmin of the asperratio of the concave-convex surface shape of resulting light-diffusing film, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.00, and average positive briliancy is 5500cd/m ², shown good performance.

[embodiment 1-13]

With obtaining the matrix material film of 120 microns of thickness with the same method of embodiment 1-12.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.157×x)+5×sin(0.0628×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

Maximal value Asmax, the minimum value Asmin of the asperratio of the concave-convex surface shape of resulting light-diffusing film, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.01, and average positive briliancy is 5600cd/m ², shown good performance.

[embodiment 1-14]

With obtaining the matrix material film of 120 microns of thickness with the same method of embodiment 1-12.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.314×x)+5×sin(0.126×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

Maximal value Asmax, the minimum value Asmin of the asperratio of the concave-convex surface shape of resulting light-diffusing film, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.00, and average positive briliancy is 5600cd/m ², shown good performance.

[embodiment 1-15]

With obtaining the matrix material film of 120 microns of thickness with the same method of embodiment 1-12.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.471×x)+5×sin(0.236×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

Maximal value Asmax, the minimum value Asmin of the asperratio of the concave-convex surface shape of resulting light-diffusing film, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.00, and average positive briliancy is 5600cd/m ², shown good performance.

[embodiment 1-16]

To main extruder, supply with: make IC-PET (fusing point TB:225 ℃) as the main resinous principle that constitutes light-diffusing film with 96 volume %, the sphere that mixes with 4 volume % as the polymethylpentene of light diffusing member.In addition, use the secondary extruder different, supply with the sphere of PET (fusing point TA:265 ℃) to this pair extruder with main extruder.Then, carry out that fusion 3 is folded layer by layer extrudes in the lump, make on the top layer, both sides of the component layer that supplies to main extruder, supplied to the component layer of secondary extruder, press thickness ratio: the component layer of secondary extruder: the component layer of main extruder: the component layer of secondary extruder=ground was stacked in 1: 8: 1.Applying method by means of static cools off on the casting cylinder of minute surface and makes 3 laminations layer by layer.Make this stacked under 87 ℃ of temperature, to extend to 3.2 times in the longitudinal direction, then, with stenter by 95 ℃ the preheating zone and on Width, extend to 3.4 times with 110 ℃.And then heat treatment temperature TH is set at 235 ℃ carries out thermal treatment in 30 seconds, obtain the matrix material film of 120 microns of thickness thus.

With with the same method of embodiment 1-4 at this matrix material film, on a side surface, form concaveconvex shape.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.314×x)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

The maximal value Asmax of the asperratio of the surface configuration of resulting light-diffusing film, minimum value Asmin, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.01, and average positive briliancy is 5700cd/m ², shown good performance.

[embodiment 1-17]

Make, launch following cloth and silk, be fixed to the area source housing with two sides splicing tape (a day eastern electrician (strain) produces No.500).Overlapping for making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is cloth and silk one side) in the top of this cloth and silk (with face) resulting light-diffusing film in embodiment 1-16 in the face of the opposite side of a side of fluorescent light.The uniformity coefficient of this area source is 1.00, and average positive briliancy is 5900cd/m ², show good performance.In addition, for realize by cloth and silk concerning the support of light-diffusing film, cloth and silk can not curl substantially, is good.

(formation of cloth and silk)

1, the yarn of Shi Yonging: warp (84dtex-72 bar monofilament, polyester 100% long filament), parallel (84dtex-72 bar monofilament, polyester 100% long filament)

2, weave: plain weave is knitted

3, weaving density: vertically weaving density is 110/inch, and laterally weaving density is 90/inch.

Whole light transmittances, the mist degree of the cloth and silk made from above-mentioned formation are respectively 51%, 90%.

[comparative example 1-1]

To main extruder, supply with: make IC-PET (fusing point TB:225 ℃) as the main resinous principle that constitutes light-diffusing film with 92 volume %, the sphere that mixes with 8 volume % as the polymethylpentene of light diffusing member.In addition, use the secondary extruder different, supply with the sphere of PET (fusing point TA:265 ℃) to this pair extruder with main extruder.Then, carry out the folded layer by layer top layer, both sides that makes at the component layer that supplies to main extruder of extruding in the lump of fusion 3, supplied to the component layer of secondary extruder, by thickness ratio: become the component layer for secondary extruder: the component layer of main extruder: the component layer of secondary extruder=ground was stacked in 1: 8: 1.Applying method by means of static cools off on the casting cylinder of minute surface and makes 3 laminations layer by layer.Make this stacked under 87 ℃ of temperature, to extend to 3.2 times in the longitudinal direction, then, with stenter by 95 ℃ the preheating zone and on Width, extend to 3.4 times with 110 ℃.And then heat treatment temperature TH is set at 235 ℃ carries out thermal treatment in 30 seconds, obtain the matrix material film of 150 microns of thickness thus.

Do not add any change ground resulting matrix material film is used as light-diffusing film.This light-diffusing film, two sides are smooth, and the individual number density of the light diffusing member of film section, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness are as shown in table 1.In addition, polymethylpentene, the result that section is observed disperses spherically, and mean grain size (diameter) is 5.2 microns.

The uniformity coefficient that is laid with the area source of this light-diffusing film is 1.42, and average positive briliancy is 4800cd/m ²

[comparative example 1-2]

To main extruder, supply with the sphere of PET as the main resinous principle that constitutes film.Then, melt extrude, apply method by means of static and on the casting cylinder of minute surface, cool off, make single-layer sheet.Make this single-layer sheet under 87 ℃ of temperature, extend to 3.2 times in the longitudinal direction, then, with stenter by 95 ℃ the preheating zone and on Width, extend to 3.4 times with 110 ℃.And then heat treatment temperature TH is set at 235 ℃ carries out thermal treatment in 30 seconds, obtain the matrix material film of 150 microns of thickness thus.

At resulting matrix material film, use with the same method of embodiment 1-6 and form concaveconvex shape on a side surface.

Consequently, the maximal value Asmax of the asperratio of the surface configuration of resulting light-diffusing film, minimum value Asmin, each is to different degree, transmissivity, mist degree, gross thickness, and is as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.68, and average positive briliancy is 5000cd/m ²

[comparative example 1-3]

Except the extrusion capacity that has changed main extruder and secondary extruder, use the matrix material film that obtains 120 microns of thickness with the same method of embodiment 1-5.In addition, the thickness ratio is the component layer of secondary extruder: the component layer of main extruder: the component layer of secondary extruder=1: 8: 1.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.0942×x)+5×sin(0.0942×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

Maximal value Asmax, the minimum value Asmin of the asperratio of the concave-convex surface shape of resulting light-diffusing film, each individual number density, area ratio/occupancy ratio, transmissivity, mist degree, gross thickness to the light diffusing member of different degree, film section, as shown in table 1.In addition, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.In addition, polymethylpentene, the result that section is observed disperses spherically, and mean grain size (diameter) is 5 microns.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.22, and average positive briliancy is 5100cd/m ²

[embodiment 2-1]

Make m-phthalic acid for acid unit 10mol%, cyclohexanedimethanol and PET copolymerization for ethylene glycol unit 10mol% are got up, be made into vibrin (225 ℃ of fusing points) (below, be called " IC-PET "), supply with to main extruder: make above-mentioned vibrin as the main resinous principle that constitutes light-diffusing film with 98 volume %, the sphere that mixes with 2 volume % as the polymethylpentene of light diffusing member, in addition, with the secondary extruder different, supply with the sphere of PET (265 ℃ of fusing points) to this pair extruder with main extruder.Then, carry out the folded layer by layer top layer, both sides that makes at the component layer that supplies to main extruder of extruding in the lump of fusion 3, supplied to the component layer of secondary extruder, pressed thickness ratio: the composition ratio of secondary extruder: the composition ratio of main extruder: the composition of secondary extruder is than=1: ground was stacked in 8: 1.Applying method by means of static makes the resin cooling of being extruded and makes 3 laminations layer by layer on the casting cylinder of minute surface.Make this stacked under 88 ℃ of temperature, to extend to 3.3 times in the longitudinal direction, then, with stenter by 95 ℃ the preheating zone and on Width, extend to 3.5 times with 115 ℃.And then heat treatment temperature is set at 240 ℃ carries out thermal treatment in 30 seconds, obtain the matrix material film of 140 microns of thickness thus.

Form concaveconvex shape at this matrix material film, on a side surface with following method.In addition, here, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.314×x)+5×sin(0.251×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

At first, with ultraviolet curable resin: (チ バ ス ペ シ ヤ Le テ イ ケ ミ カ Le ズ (strain) produces: (produce: ユ ニ デ イ Star Network 15-829) イ Le ガ キ ユ ア 907) to be mixed into ultraviolet curable resin by big Japanese ink chemical industry (strain) initiating agent for the ratio of initiating agent=99: 1, carry out mixing stirring in 30 minutes with stirring machine, obtain masking liquid.Then, this masking liquid is applied to make that at the face that is formed with surface configuration of mould, it is 50 microns that the thickness of filming becomes.After coating, the matrix material film mounting to the upper surface of filming, is made it to be adjacent to.Then from of the ultraviolet ray of matrix material face one side for die face direction irradiation total 500mJ/W.After the ultraviolet ray irradiation, carry out 30 minutes heat fixations at 40 ℃.Then, adopt the way make mold releasability, obtain the ultraviolet curable resin layer that has formed the concave-convex surface shape is laminated to a side's of matrix material film the light-diffusing film of face.

Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, as shown in table 2.Here, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.As for BI, Bmax, Bmin, be never to form the numerical value that the face incident ray of concave-convex surface shape is measured.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.08, and average positive briliancy is 5900cd/m ², shown good performance.

[embodiment 2-2]

With obtaining the matrix material film of 140 microns of thickness with the same method of embodiment 2-1.With with the same method of embodiment 2-1 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.314×x)+5×sin(0.188×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, as shown in table 2.Here, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.As for BI, Bmax, Bmin, be never to form the numerical value that the face incident ray of concave-convex surface shape is measured.

This light-diffusing film laid to making the face formed the concave-convex surface shape become be observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.06, and average positive briliancy is 5800cd/m ², shown good performance.

[embodiment 2-3]

With obtaining the matrix material film of 140 microns of thickness with the same method of embodiment 2-1.

With with the same method of embodiment 2-1 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.314×x)+5×sin(0.126×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, as shown in table 2.Here, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.As for BI, Bmax, Bmin, be never to form the numerical value that the face incident ray of concave-convex surface shape is measured.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.04, and average positive briliancy is 5700cd/m ², shown good performance.

[embodiment 2-4]

With obtaining the matrix material film of 140 microns of thickness with the same method of embodiment 2-1.

With with the same method of embodiment 2-1 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.251×x)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, as shown in table 2.Here, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.As for BI, Bmax, Bmin, be never to form the numerical value that the face incident ray of concave-convex surface shape is measured.

This light-diffusing film laid to making the face formed the concave-convex surface shape become be observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.03, and average positive briliancy is 5900cd/m ², shown good performance.

[embodiment 2-5]

With obtaining the matrix material film of 140 microns of thickness with the same method of embodiment 2-1.

With with the same method of embodiment 2-1 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.440×x)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, as shown in table 2.Here, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.As for BI, Bmax, Bmin, be never to form the numerical value that the face incident ray of concave-convex surface shape is measured.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.03, and average positive briliancy is 5800cd/m ², shown good performance.

[embodiment 2-6]

With obtaining the matrix material film of 140 microns of thickness with the same method of embodiment 2-1.

With with the same method of embodiment 2-1 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.628×x)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, as shown in table 2.Here, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.As for BI, Bmax, Bmin, be never to form the numerical value that the face incident ray of concave-convex surface shape is measured.

This light-diffusing film laid to making the face formed the concave-convex surface shape become be observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.02, and average positive briliancy is 5800cd/m ², shown good performance.

[embodiment 2-7]

In area source resulting diffuser in embodiment 2-3 being assembled into makes the distance on surface of light source one side of the center of fluorescent tube and light-diffusing film become 23.5mm.Calculate the δ of this area source, learn to be 30 °, uniformity coefficient is 1.03, and average positive briliancy is 6000cd/m ², shown good performance.

[embodiment 2-8]

In area source resulting diffuser in embodiment 2-6 being assembled into makes the distance on surface of light source one side of the center of fluorescent tube and light-diffusing film become 23.5mm.Calculate the δ of this area source, learn to be 30 °, uniformity coefficient is 1.02, and average positive briliancy is 5900cd/m ², shown good performance.

[embodiment 2-9]

In area source resulting diffuser in embodiment 2-3 being assembled into makes the distance on surface of light source one side of the center of fluorescent tube and light-diffusing film become 15.5mm.Calculate the δ of this area source, learn to be 40 °, uniformity coefficient is 1.05, and average positive briliancy is 5600cd/m ², shown good performance.

[embodiment 2-10]

In area source resulting diffuser in embodiment 2-6 being assembled into makes the distance on surface of light source one side of the center of fluorescent tube and light-diffusing film become 15.5mm.Calculate the δ of this area source, learn to be 40 °, uniformity coefficient is 1.03, and average positive briliancy is 5700cd/m ², shown good performance.

[reference example 2-1]

To extruder, supply with the sphere of polycarbonate as the main resinous principle that constitutes light-diffusing film.Then, melt extrude, apply method by means of static and on the casting cylinder of minute surface, cool off and make single-layer sheet.

On this single-layer sheet, form concaveconvex shape on a side surface with following method.In addition, here, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.0942×x)+5×sin(0.0942×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

At first, resulting single-layer sheet and mold heated to 175 ℃, kept 2.5 minutes.Then, the face that has formed shape of mould is pressed on the single-layer sheet, kept 3 minutes with the pressure of 12MPa.Then, keep-up pressure and be cooled to 125 ℃ unchangeably, pressure relief.Make the film demoulding that has formed the concave-convex surface shape by means of mould, obtain light-diffusing film.

Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, as shown in table 2.Here, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.As for BI, Bmax, Bmin, be never to form the numerical value that the face incident ray of concave-convex surface shape is measured.

This light-diffusing film laid to making the face formed the concave-convex surface shape become be observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.19, and average positive briliancy is 6100cd/m ²

[reference example 2-2]

Make cyclohexanedimethanol and PET copolymerization for ethylene glycol unit 20mol%, be made into vibrin, supply with to extruder: make above-mentioned vibrin as the main resinous principle that constitutes light-diffusing film with 99.8 volume %, the sphere that mixes with 0.2 volume % as the polymethylpentene of light diffusing member.Then, melt extrude, apply method by means of static and on the casting cylinder of minute surface, cool off and make single-layer sheet.

On this single-layer sheet, form concaveconvex shape on a side surface with following method.In addition, here, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.157×x)+5×sin(0.157×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

At first, resulting single-layer sheet and mold heated to 135 ℃, kept 3 minutes.Then, the face that has formed shape of mould is pressed to single-layer sheet, kept 3 minutes with the pressure of 10MPa.Then, keep-up pressure and be cooled to 65 ℃ unchangeably, pressure relief.Make the film demoulding that has formed the concave-convex surface shape by means of mould, obtain light-diffusing film.

Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, as shown in table 2.Here, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.As for BI, Bmax, Bmin, be never to form the numerical value that the face incident ray of concave-convex surface shape is measured.

This light-diffusing film laid to making the face formed the concave-convex surface shape become be observer's direction (face that does not form concave-convex surface is light source one side).The uniformity coefficient of this area source is 1.14, and average positive briliancy is 5800cd/m ²

[reference example 2-3]

Make m-phthalic acid for acid unit 10mol%, cyclohexanedimethanol and PET copolymerization for ethylene glycol unit 10mol%d are got up, be made into vibrin (225 ℃ of fusing points) (below, be called " IC-PET "), supply with to main extruder: make above-mentioned vibrin as the main resinous principle that constitutes light-diffusing film with 98 volume %, the sphere that mixes with 2 volume % as the polymethylpentene of light diffusing member, in addition, with the secondary extruder different, supply with the sphere of PET (fusing point is 265 ℃) to this pair extruder with main extruder.Then, carry out that fusion 3 is folded layer by layer extrudes in the lump, make on the top layer, both sides of the component layer that supplies to main extruder, supplied to the component layer of secondary extruder, press thickness ratio: the composition ratio of secondary extruder: the composition ratio of main extruder: the composition of secondary extruder is than=1: ground was stacked in 8: 1.Applying method by means of static cools off on the casting cylinder of minute surface and makes 3 laminations layer by layer.Make this stacked under 88 ℃ of temperature, to extend to 3.3 times in the longitudinal direction, then, with stenter by 95 ℃ the preheating zone and on Width, extend to 3.5 times with 115 ℃.And then heat treatment temperature is set at 240 ℃ carries out thermal treatment in 30 seconds, obtain thick 390 microns matrix material film thus.

Form concaveconvex shape at this matrix material film, on a side surface with following method.In addition, here, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

z＝5×sin(0.314×x)+5×sin(0.314×y)

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.

At first, with ultraviolet curable resin: (チ バ ス ペ シ ヤ Le テ イ ケ ミ カ Le ズ (strain) produces: (produce: ユ ニ デ イ Star Network 15-829) イ Le ガ キ ユ ア 907) to be mixed into ultraviolet curable resin by big Japanese ink chemical industry (strain) initiating agent for the ratio of initiating agent=99: 1, carry out mixing stirring in 30 minutes with stirring machine, obtain masking liquid.Then, this masking liquid is applied to make that at the face that is formed with surface configuration of mould, the thickness of filming becomes 50 microns.After coating, the matrix material film mounting to the upper surface of filming, is made it to be adjacent to.Then from of the ultraviolet ray of matrix material face one side for die face direction irradiation total 500mJ/W.After the ultraviolet ray irradiation, under 40 ℃, carry out 30 minutes heat fixations.Then, adopt the way make mold releasability, obtain the ultraviolet curable resin layer that has formed the concave-convex surface shape is laminated to a side's of matrix material film the light-diffusing film of face.

Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, as shown in table 2.Here, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.As for BI, Bmax, Bmin, be never to form the numerical value that the face incident ray of concave-convex surface shape is measured.

This light-diffusing film laid to making the face formed the concave-convex surface shape become be observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.10, and average positive briliancy is 5800cd/m ²

[comparative example 2-1]

To main extruder, supply with: make IC-PET as the main resinous principle that constitutes light-diffusing film with 90 volume %, the sphere that the polymethylpentene as light diffusing member is mixed with 10 volume %.In addition, use the secondary extruder different, supply with the sphere of PET (265 ℃ of fusing points) to this pair extruder with main extruder.Then, carry out that fusion 3 is folded layer by layer extrudes in the lump, make on the top layer, both sides of the component layer that supplies to main extruder, supplied to the component layer of secondary extruder, press thickness ratio: the composition ratio of secondary extruder: the composition ratio of main extruder: the composition of secondary extruder is than=1: ground was stacked in 8: 1.Applying method by means of static cools off on the casting cylinder of minute surface and makes 3 laminations layer by layer.Make this stacked under 88 ℃ of temperature, to extend to 3.3 times in the longitudinal direction, then, with stenter by 95 ℃ the preheating zone and on Width, extend to 3.5 times with 115 ℃.And then heat treatment temperature is set at 240 ℃ carries out thermal treatment in 30 seconds, obtain thick 140 microns matrix material film thus.

Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, as shown in table 2.

This light-diffusing film of assembling in area source.The uniformity coefficient of this area source is 1.24, and average positive briliancy is 4300cd/m ²

[comparative example 2-1]

To main extruder, supply with: make IC-PET as the main resinous principle that constitutes light-diffusing film with 98 volume %, the sphere that polymethylpentene as light diffusing member is mixed with 2 volume %, in addition, with the secondary extruder different, supply with the sphere of PET (265 ℃ of fusing points) to this pair extruder with main extruder.Then, carry out that fusion 3 is folded layer by layer extrudes in the lump, make on the top layer, both sides of the component layer that supplies to main extruder, supplied to the component layer of secondary extruder, press thickness ratio: the composition ratio of secondary extruder: the composition ratio of main extruder: the composition of secondary extruder is than=1: ground was stacked in 8: 1.Applying method by means of static cools off on the casting cylinder of minute surface and makes 3 laminations layer by layer.Make this stacked under 88 ℃ of temperature, to extend to 3.3 times in the longitudinal direction, then, with stenter by 95 ℃ the preheating zone and on Width, extend to 3.5 times with 115 ℃.And then heat treatment temperature is set at 240 ℃ carries out thermal treatment in 30 seconds, obtain thick 140 microns matrix material film thus.

Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, as shown in table 2.

This light-diffusing film of assembling in area source.The uniformity coefficient of this area source is 1.79, and average positive briliancy is 5200cd/m ²

[comparative example 2-3]

In area source resulting diffuser in comparative example 2-2 being assembled into makes the distance on surface of light source one side of the center of fluorescent tube and light-diffusing film become 23.5mm.Calculate the δ of this area source, learn to be 30 °.Uniformity coefficient is 1.73, and average positive briliancy is 5300cd/m ²

[comparative example 2-4]

In area source resulting diffuser in comparative example 2-2 being assembled into makes the distance on surface of light source one side of the center of fluorescent tube and light-diffusing film become 15.5mm.Calculate the δ of this area source, learn to be 40 °.Uniformity coefficient is 1.86, and average positive briliancy is 5000cd/m ²

[embodiment 3-1]

With obtaining the matrix material film of 120 microns of thickness with the same method of embodiment 1-16.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is the mould that has formed the nickel system of the curved surface that available following formula represents.

{(x+n×100) ²/50 ²}+{z ²/37.5 ²}＝1

Wherein ,-50≤(x+n * 100)≤50 (n=0, ± 1, ± 2, ± 3...), z≤0.

Here, z is the mold thickness direction, and x, y are the die face directions.In addition, unit is a micron.In other words, the section shape of mould is shown in Figure 10, in addition, does not have concavo-convexly on the y direction of principal axis, and shape has just become the ribbon lens post.Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, shown in table 3,4.Here, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.As for BI, Bmax, Bmin, be never to form the numerical value that the face incident ray of concave-convex surface shape is measured.

This light-diffusing film laid to making the face formed the concave-convex surface shape become be observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.01, and average positive briliancy is 5700cd/m ², shown good performance.

[embodiment 3-2]

With obtaining the matrix material film of 120 microns of thickness with the same method of embodiment 1-16.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is to have formed the A side end of unit curve form shown in Figure 11 and B side end (A-END of Figure 11 and the B-END) mould of the nickel system of articulate shape continuously.Here, z is the mold thickness direction, and x, y are the die face directions.In addition, do not have concavo-convexly on the y direction of principal axis, shape has just become the ribbon lens post.

Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, shown in table 3,4.Here, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.As for BI, Bmax, Bmin, be never to form the numerical value that the face incident ray of concave-convex surface shape is measured.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.00, and average positive briliancy is 5800cd/m ², shown good performance.

[embodiment 3-3]

With obtaining the matrix material film of 120 microns of thickness with the same method of embodiment 1-16.

With with the same method of embodiment 1-4 at this matrix material film, form concaveconvex shape on a side surface.Wherein, employed mould is to have formed the A side end of unit curve form shown in Figure 12 and B side end (A-END of Figure 12 and the B-END) mould of the nickel system of articulate shape continuously.Here, z is the mold thickness direction, and x, y are the die face directions.In addition, do not have concavo-convexly on the y direction of principal axis, shape has just become the ribbon lens post.

Maximal value Asmax, the minimum value Asmin of the difference Δ φ of the face internal rotation angle of the minimum value BI of the relative briliancy of resulting light-diffusing film, maximum average briliancy Bmax, the relative briliancy Bmin of minimum average B configuration relatively, maximal value and ratio Bmax/Bmin, the maximum average relative briliancy Bmax of expression of minimum value and the face internal rotation angle of the relative briliancy Bmin of expression minimum average B configuration, the asperratio of surface configuration, as the ratio of maximal value and minimum value respectively to different degree Asmax/Asmin, transmissivity, mist degree, gross thickness, shown in table 3,4.Here, transmissivity and mist degree are the numerical value of being measured from the face incident ray that has formed the concave-convex surface shape.As for BI, Bmax, Bmin, be never to form the numerical value that the face incident ray of concave-convex surface shape is measured.

This light-diffusing film is laid to making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side).The uniformity coefficient of this area source is 1.00, and average positive briliancy is 6000cd/m ², shown good performance.

[embodiment 3-4]

Make, launch following cloth and silk, be fixed to the area source housing with two sides splicing tape (a day eastern electrician (strain) produces No.500).On this cloth and silk (with face) in the face of the opposite side of a side of fluorescent light, make in embodiment 3-2 resulting light-diffusing film overlapping for making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is cloth and silk one side), this moment, uniformity coefficient was 1.00, and average positive briliancy is 6000cd/m ², show good performance.In addition, for realize by cloth and silk concerning the support of light-diffusing film, cloth and silk also substantially curls, and is good.

(formation of cloth and silk)

1. the yarn of Shi Yonging: warp (56dtex-18 bar monofilament, polyester 100% long filament), parallel (84dtex-36 bar monofilament, polyester 100% long filament)

2. weave: plain weave is knitted

3. weaving density: vertically weaving density is 118/inch, and laterally weaving density is 92/inch.

Whole light transmittances, mist degree with the cloth and silk of above-mentioned formation made are respectively 55%, 91%.

[comparative example 3-1]

The film that obtains in comparative example 1-1 is applied to area source, and (observer's direction) lays the film that obtains for making the face that has formed the concave-convex surface shape become observer's direction (face that does not form the concave-convex surface shape is light source one side) in comparative example 1-2 more thereon.Mist degree, transmissivity are as shown in table 4.Here, transmissivity and mist degree, be to adopt: on the film that in comparative example 1-1, obtains, overlapping for making the face formed the concave-convex surface shape become the outside the film that in comparative example 1-2, obtains, from the film that among comparative example 1-2, obtains, formed the numerical value that the face incident ray of concave-convex surface shape is measured.The uniformity coefficient of this area source is 1.27, and average positive briliancy is 5200cd/m ²

[table 4]

	Transmissivity [%]	Mist degree [%]	Integral thickness [μ m]	Cloth and silk	Uniformity coefficient [-]	Briliancy [cd/m 2]
							Embodiment 3-1	72	93	160	Do not have	1.01	5700
Embodiment 3-2	71	92	150	Do not have	1.00	5800
							Embodiment 3-3	70	93	150	Do not have	1.00	6000
Embodiment 3-4	71	92	150	Have	1.00	6000
							Comparative example 3-1	68	93	300	Do not have	1.27	5200

Light-diffusing film of the present invention, as the area source that can in the display device of personal computer, televisor or portable telephone etc., use, as the area source usefulness that can use in the flat display apparatus of liquid crystal indicator etc., being suitable particularly, is useful.

Claims (13)

1, a kind of light-diffusing film, it has the matrix material film that contains light diffusing member in inside, and the ratio Asmax/Asmin that is formed with the maximal value Asmax of average asperratio and minimum value Asmin at least on a side surface is the concave-convex surface shape more than 1.1, and what wherein Asmax/Asmin represented is that each is to different degree.

2, light-diffusing film according to claim 1, wherein, above-mentioned matrix material film is by extending more than the single shaft.

3, light-diffusing film according to claim 1 wherein, is more than 1% perpendicular to the area ratio/occupancy ratio of the above-mentioned light diffusing member of the section of face.

4, light-diffusing film according to claim 1 wherein, is 250/mm perpendicular to the individual number density of the above-mentioned light diffusing member of the section of face ²More than.

5, light-diffusing film according to claim 1, wherein, the maximal value Asmax of above-mentioned average asperratio is more than 0.3.

6, light-diffusing film according to claim 1, wherein, relative film normal to a surface direction be in 20 °～50 ° the angular range during to this film incident ray, be more than 0.0014 to the minimum value BI of the relative briliancy of the light of normal direction transmission.

7, light-diffusing film according to claim 1, wherein, relative film normal to a surface direction be in 20 °～50 ° the angular range during to this film incident ray, be more than 0.002 to the maximum average briliancy Bmax relatively of the light of normal direction transmission.

8, light-diffusing film according to claim 1, wherein, make light with relative film normal to a surface direction be 20 °～50 ° angle to this film incident, when making film carry out rotating in the face, be more than 1.1 to the maximum average ratio Bmax/Bmin of the relative briliancy Bmin of briliancy Bmax relatively of the light of normal direction transmission with minimum average B configuration.

9, light-diffusing film according to claim 1, wherein, contain in inside light diffusing member matrix material film self the surface or be coated to the overlay that contains the matrix material film of light diffusing member in inside, be formed with above-mentioned each be concave-convex surface shape more than 1.1 to different degree.

10, a kind of area source, it uses any one the described light-diffusing film in the claim 1～9.

11, area source according to claim 10, wherein, above-mentioned light-diffusing film is configured to, and is formed with that its each be that the face of the concave-convex surface shape more than 1.1 is towards observer's one side to different degree.

12, area source according to claim 11 wherein, has cloth and silk between above-mentioned light-diffusing film and light source.

13, area source according to claim 12, wherein, above-mentioned light-diffusing film is by above-mentioned cloth and silk support.

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