CN103513301A

CN103513301A - Producing method for light diffusion film

Info

Publication number: CN103513301A
Application number: CN201310176772.6A
Authority: CN
Inventors: 片桐麦; 草间健太郎; 大类知生
Original assignee: Lintec Corp
Current assignee: Lintec Corp
Priority date: 2012-06-15
Filing date: 2013-05-14
Publication date: 2014-01-15
Anticipated expiration: 2033-05-14
Also published as: KR20130141365A; JP2014002188A; TW201350928A; TWI605271B; KR102000512B1; CN103513301B; JP5999992B2

Abstract

The invention is aiming to provide a method for effectively producing a light diffusion film having a good dependence on an incident light angle and a wide spread diffusion area in a light transmission and a diffusion phenomena, by using a linear light source. Thus, the method for producing a light diffusion film having a first structure region and a second structure region, includes steps (a) to (d) as described in below: (a) a process for preparing a composition for the light diffusion film, (b) a process for forming a coating layer, (c) a process for forming a specific louver-structure region at the lower part of the coating layer as the first structure region, as well as maintaining a specific un-composed louver area at the upper part of the coating layer, and (d) a process for forming a specific column-structure region at the un-composed louver area of the coating layer as the second structure region by irradiation of an active energy ray via a parallel member for the active energy ray from a linear light source to the coating layer.

Description

The manufacture method of optical diffusion film

Technical field

The present invention relates to the manufacture method of optical diffusion film.The present invention be more particularly directed to by containing being useful on the shutter region that makes incident light carry out anisotropic light diffusion and for making incident light carry out the rod structure region of isotropy light diffusion, thereby can utilize linear light source and easily obtain having the manufacture method of the wide optical diffusion film of good incident angle dependence and light diffusion incident angle region in optical transmission and diffusion.

Background technology

In the past, in liquid crystal indicator, the light that can utilize the light source (internal light source) from being arranged at device inside to penetrate was identified specified image.

Yet in recent years, universal due to mobile phone, vehicle mounted TV etc., increases in the outdoor chance of liquid crystal display picture of watching, and follows therewith, produced from the light intensity of internal light source and be defeated by exterior light and become and be difficult to identify the problem of regulation picture.

If in addition, in the mobile purposes of mobile phone etc., the power consumption of the internal light source of liquid crystal indicator occupies significant proportion with respect to wastage in bulk or weight electric power, so while often using internal light source, produce the problem that duration of battery shortens.

Therefore,, in order to address these problems, developing exterior light as the reflection-type liquid-crystal display device of a part for light source.

If above-mentioned reflection-type liquid-crystal display device due to a part of utilizing exterior light as light source, so exterior light is stronger, more can be identified distinct image, and also can effectively suppress for the power consumption of internal light source.

In addition, in such reflection-type liquid-crystal display device, following scheme has been proposed: in order to make exterior light transmission and taken in the inside of liquid crystal indicator and effectively utilize this exterior light as a part for light source efficiently, possesses the optical diffusion film (for example,, with reference to patent documentation 1) for carrying out efficiently light diffusion.

More specifically, liquid-crystal apparatus 1112 is disclosed in patent documentation 1, as shown in Figure 29 (a)～(b), its have the liquid crystal cells that between upper substrate 1103 and infrabasal plate, clamping liquid crystal layer 1105 forms, be arranged at the light reflecting board 1110 of infrabasal plate 1,107 one sides and be arranged at liquid crystal layer 1105 and light reflecting board 1110 between Opital control board (optical diffusion film) 1108.

And, be provided with for making with the scattering and make the light transmissive Opital control board 1108 with the angle incident beyond predetermined angular selectively of the light of predetermined angular incident, above-mentioned Opital control board 1108 is axial 1121 with the scattering that the direction projection of scattering forms to the surface of Opital control board 1108 selectively of the light of predetermined angular incident, becomes the direction of the direction of 6 o'clock roughly in liquid crystal cells inside.

Herein, as the optical diffusion film using in reflection-type liquid-crystal display device, disclose by using linear light source to irradiate active energy ray to specific light solidification compound, thereby in the either direction along face, make alternately configured in parallel of the plate like region of high index of refraction and the plate like region of low-refraction, in film, form the optical diffusion film (for example, patent documentation 2～3) that shutter region forms.

; a kind of light control film is disclosed in patent documentation 2; it is characterized in that; this light control film (optical diffusion film) from specific direction to containing the multiple membranaceous composition irradiation ultraviolet radiation with the compound of polymerism carbon-to-carbon double bond, said composition is solidified obtain; the incident light of scattering special angle scope selectively only, at least a kind of compound comprising in said composition is the compound in molecule with a plurality of aromatic rings and a polymerism carbon-to-carbon double bond.

In addition, in patent documentation 3, disclose a kind of Photocurable composition and made it solidify the light control film forming, above-mentioned Photocurable composition is characterised in that, the fluorenes based compound (A) that contains the carbon-to-carbon double bond in molecule with polymerism, cationically polymerizable compound (B) and the light cationic polymerization initiators (C) different from this fluorenes based compound (A) refractive index.

On the other hand, optical diffusion film as other type of using in reflective liquid crystal device, a kind of optical diffusion film is disclosed, it forms as follows: by specific light solidification compound is irradiated to the active energy ray as directional light by entire surface, thereby the film thickness direction along film, the rod structure region (for example,, with reference to patent documentation 4～6) that formation is stood in great numbers more much higher column of refractive index in refractive index compare Di region.

; a kind of manufacture method of dispersive medium is disclosed in patent documentation 4; it is characterized in that; that the composition that contains photocurable compound is set as to sheet; from the direction P of regulation, this sheet is irradiated to parallel rays and composition is solidified and can be in the manufacture method of the dispersive medium (optical diffusion film) of the inner aggregate that forms a plurality of bar-shaped consolidation zone of extending abreast with direction P of sheet; wherein; between linear light source and sheet, accompany the set of the tubular article configuring abreast with direction P, and carry out irradiation by this tubular article.

In addition, a kind of manufacturing installation of light control film is disclosed in citing document 5, it is characterized in that, this manufacturing installation is to configure linear light source with the mode of Photocurable resin composition film spaced, opposed, at least one in the mobile Photocurable resin composition film in one side and linear light source, from linear light source, irradiate light and make Photocurable resin composition film be solidified to form light control film (optical diffusion film) on one side, wherein, axially intersecting with moving direction of linear light source, opposed multiple lamellar light-blocking members arrange as follows mutually, , between Photocurable resin composition film and linear light source, in the direction substantially vertical with respect to moving direction, for predetermined distance, and light-blocking member become equidirectional with moving direction respectively with the opposed one side of Photocurable resin composition film.

In addition, a kind of reflection projection screen is disclosed in patent documentation 6, it is characterized in that, possesses diffusion layer (diffusion barrier), this diffusion layer covers and configures as the Fresnel face of the linear Fresnel component of reflecting surface as extinction face the dip plane of usining downward towards the end face of top usining, the light diffusion property with the incident light diffusion that does not make to be greater than regulation angle, wherein, this diffusion layer generates by the 1st irradiation operation and the 2nd irradiation operation, described the 1st irradiation operation is for being situated between and by the photomask in territory, Photocurable resin composition not irradiated to directional light by having light by territory and light from prescribed direction, make irradiated position be cured as incomplete solid state, described the 2nd irradiation operation is for taking off photomask, further towards Photocurable composition, irradiate the directional light of light intensity distributions constant, finish solidifying of Photocurable composition, in this film, possesses phase separation structure, this phase separation structure possesses the matrix consisting of Photocurable composition in this film, and in the mode of extending on the direction of illumination of directional light, be orientated and a plurality of columnar structures different from this matrix refractive index in this matrix.

Patent documentation 1: No. 3480260 communiques of Jap.P. (claims, accompanying drawing etc.)

Patent documentation 2: TOHKEMY 2006-350290 communique (claims, accompanying drawing etc.)

Patent documentation 3: TOHKEMY 2008-239757 communique (claims, accompanying drawing etc.)

Patent documentation 4: No. 4095573 communiques of Jap.P. (claims, accompanying drawing etc.)

Patent documentation 5: TOHKEMY 2009-173018 communique (claims, accompanying drawing etc.)

Patent documentation 6: TOHKEMY 2008-256930 communique (claims, accompanying drawing etc.)

Summary of the invention

Yet, with regard to the disclosed optical diffusion film with shutter region in patent documentation 1～3, found in their formation, the incident angle region that cannot fully expand the incident light that can carry out light diffusion is (following, be sometimes referred to as light diffusion incident angle region), and then, the opening angle of the diffusion light situation such as narrow that also becomes sometimes.

In addition, with regard to the disclosed optical diffusion film with rod structure region in patent documentation 4～6, found following problem: compare with the optical diffusion film with shutter region, reflection of light in film easily produces inequality, so the fluctuation of the light diffusion property of the incident angle based on incident light is large, be difficult to bring into play good incident angle dependence.

In addition, the optical diffusion film that has separately shutter region or have separately rod structure region is only disclosed in patent documentation 1～6, so do not mention for the manufacture method simultaneously in single film with the optical diffusion film of these two kinds of structural regions, without any recording or enlightenment.

Therefore, the inventor etc. are in view of as above situation and through going deep into effort, found that shutter region by being provided for making incident light carry out anisotropic light diffusion and for making incident light carry out the rod structure region of isotropy light diffusion in film, thereby can obtain having the wide optical diffusion film of good incident angle dependence and light diffusion incident angle region.

And then, the discoveries such as the inventor, by being used to form successively that the 1st active energy ray in shutter region irradiates and Jie of being used to form rod structure region is irradiated by irradiating the 2nd active energy ray that parallel light parts carry out, thereby can utilize linear light source and easily obtain having the optical diffusion film of above-mentioned characteristic, thereby having completed the present invention.

That is, the object of the present invention is to provide a kind of linear light source that can utilize easily to obtain having the wide optical diffusion film of good incident angle dependence and light diffusion incident angle region in optical transmission and diffusion.

According to the present invention, a kind of manufacture method of optical diffusion film can be provided and address the above problem, the manufacture method of above-mentioned optical diffusion film is characterised in that, be to have for making incident light carry out the 1st structural region of anisotropic light diffusion and for making incident light carry out the manufacture method of optical diffusion film of the 2nd structural region of isotropy light diffusion, comprise following operation (a)～(d):

(a) prepare the operation of composition for optical diffusion film;

(b), to technique sheet material coating optical diffusion film composition, form the operation of coating layer;

(c) to coating layer, carrying out the 1st active energy ray irradiates, below coating layer part form as the 1st structural region the different a plurality of plate like region of refractive index are alternately configured to the shutter region forming in the either direction along face, and in the residual operation that does not form the region of shutter of upper section of coating layer;

(d) to coating layer, further carrying out the 2nd active energy ray irradiates, in the region that does not form shutter, form the rod structure region that the relatively much higher column of refractive index is stood in great numbers in the relative Di of refractive index region as the 2nd structural region, wherein, as the 2nd active energy ray, irradiate, coating layer is situated between and irradiates the operation from the irradiation light of linear light source by irradiating parallel light parts.

; if the manufacture method of optical diffusion film of the present invention; by being used to form successively, the 1st active energy ray in shutter region irradiates and Jie of being used to form rod structure region is irradiated by the 2nd active energy ray that irradiates parallel light parts, thereby manufactures optical diffusion film.

Therefore, even while all using linear light source in the 1st and the 2nd active energy ray irradiates, also can be in single film respectively efficiency form well as for make incident light in film, carry out anisotropic light diffusion the 1st structural region shutter region and as for making incident light carry out the rod structure region of the 2nd structural region of isotropy light diffusion in film.

Its result, by making the incident angle dependence that each structural region has carry out repetition, thus the optical diffusion film of the light diffusion property fluctuation that can easily be inhibited.

In addition, different by the incident angle dependence that each structural region is had, thus for the optical diffusion film that has effectively expanded light diffusion incident angle region, also can easily obtain.

Should illustrate, in the present invention, " light diffusion incident angle region " refer to, for anisotropic light-diffusing film, and while changing the angle from the incident light of pointolite, the angular range of the incident light corresponding with the diffusion light of sending.Detailed content for above-mentioned light diffusion incident angle region, is described later.

In addition, " good incident angle dependence " refer to, produces incident light light diffusion the incident angle region of film (light diffusion incident angle region) and the difference not producing between other incident angle region that light spreads are clearly controlled.

And then " anisotropy " in the present invention refers to, the enlarged shape of diffusion light has anisotropy, and " isotropy " refers to, the enlarged shape of diffusion light has isotropy, but also describes in detail in the back for these.

In addition, while implementing the manufacture method of optical diffusion film of the present invention, preferably irradiate parallel light parts and formed by a plurality of plate-shaped members, and while seeing from film top, a plurality of plate-shaped members respectively configured in parallel form.

By such enforcement, thereby in the 2nd active energy ray irradiates, can easily the irradiation light from linear light source be changed into the directional light of the depth of parallelism with regulation.

In addition, while implementing the manufacture method of optical diffusion film of the present invention, the value in the plate-shaped member that preferably makes the adjacency in a plurality of plate-shaped members scope that is spaced apart 1～100mm each other.

By such enforcement, thereby in the 2nd active energy ray irradiates, can more efficiently the irradiation light from linear light source be changed into the directional light of the depth of parallelism with regulation.

In addition, when implementing the manufacture method of optical diffusion film of the present invention, while preferably seeing from film top, at the axis direction of plate-shaped member and linear light source, intersects towards configuring irradiation parallel light parts.

By such enforcement, thereby in the 2nd active energy ray irradiates, can further efficiently the irradiation light from linear light source be changed into the directional light of the depth of parallelism with regulation.

In addition, when implementing the manufacture method of optical diffusion film of the present invention, preferably irradiate the aggregate that parallel light parts are a plurality of cartridges.

By such enforcement, thereby in the 2nd active energy ray irradiates, can more easily the irradiation light from linear light source be changed into the directional light of the depth of parallelism with regulation.

In addition, when implementing the manufacture method of optical diffusion film of the present invention, the value in the scope that the maximum gauge that preferably makes cartridge is 1～100mm.

In addition, when implementing the manufacture method of optical diffusion film of the present invention, the value in the scope that preferably to make to irradiate parallel light parts Zhong upper end be 10～1000mm to the length of lower end.

In addition, when implementing the manufacture method of optical diffusion film of the present invention, preferably make to irradiate the value in the scope that the distance between the upper end of parallel light parts and the lower end of linear light source is 0～1000mm.

In addition, when implementing the manufacture method of optical diffusion film of the present invention, preferably make to irradiate the value in the lower end of parallel light parts and scope that the distance between painting layer surface is 0～1000mm.

By such enforcement, thereby in the 2nd active energy ray irradiates, can to coating layer, irradiate more efficiently the directional light of the depth of parallelism with regulation.

Should illustrate, the irradiation parallel light parts that use during the 2nd active energy ray irradiates refer to the parts that improve the depth of parallelism of irradiating light.More specifically, irradiate parallel light parts and refer to that the depth of parallelism that can make to irradiate light is the parts of 10 ° of following values.

By such enforcement, thereby can more stably form the rod structure region as the 2nd structural region.

Accompanying drawing explanation

Fig. 1: Fig. 1 (a)～(b) is in order to illustrate as the summary in the shutter region of the 1st structural region and the figure providing.

Fig. 2: Fig. 2 (a)～(b) is the figure for incident angle dependence in shutter region and anisotropy being described and providing.

Fig. 3: Fig. 3 (a)～(b) is another figure providing for the incident angle dependence in shutter region is described.

Fig. 4: Fig. 4 is the figure providing for the opening angle of incident angle and diffusion light is described.

Fig. 5: Fig. 5 (a)～(b) is in order to illustrate as the summary in the rod structure region of the 2nd structural region and the figure providing.

Fig. 6: Fig. 6 (a)～(b) is the figure for incident angle dependence in rod structure region and isotropy being described and providing.

Fig. 7: Fig. 7 (a)～(b) is the figure providing for the summary of the optical diffusion film that utilizes manufacture method of the present invention and obtain is described.

Fig. 8: Fig. 8 (a)～(b) is the figure providing for the 1st active energy ray irradiation process is described.

Fig. 9: Fig. 9 (a)～(b) is another figure providing for the 1st active energy ray irradiation process is described.

Figure 10: Figure 10 (a)～(c) is the figure providing for the 2nd active energy ray irradiation process is described.

Figure 11: Figure 11 (a)～(b) is another figure providing for the 2nd active energy ray irradiation process is described.

Figure 12: Figure 12 (a)～(d) is another figure providing for the 2nd active energy ray irradiation process is described.

Figure 13: Figure 13 (a)～(c) is in order to illustrate as the mode in the shutter region of the 1st structural region and the figure providing.

Figure 14: Figure 14 (a)～(d) is in order to illustrate as the mode in the rod structure region of the 2nd structural region and the figure providing.

Figure 15: Figure 15 utilizes manufacture method of the present invention and the Application Example of the optical diffusion film that obtains and the figure that provides in order to illustrate in reflection-type liquid-crystal display device.

Figure 16: Figure 16 is the figure providing for the optical diffusion film of embodiment 1 is described.

Figure 17: Figure 17 (a)～(b) is for the situation in cross section of optical diffusion film of embodiment 1 being described and the photo that provides.

Figure 18: Figure 18 is the figure providing for the optical diffusion film of embodiment 2 is described.

Figure 19: Figure 19 (a)～(b) is for the situation in cross section of optical diffusion film of embodiment 2 being described and the photo that provides.

Figure 20: Figure 20 (a)～(k) is the figure providing for the expansion of the diffusion light in the optical diffusion film of description references example 1 and its Luminance Distribution.

Figure 21: Figure 21 (a)～(b) is for the situation in the cross section of the optical diffusion film of description references example 1 and the photo providing.

Figure 22: Figure 22 is the figure providing for the optical diffusion film of description references example 2.

Figure 23: Figure 23 (a)～(h) is the figure providing for the expansion of the diffusion light in the optical diffusion film of description references example 3 and its Luminance Distribution.

Figure 24: Figure 24 (a)～(g) is the figure providing for the expansion of the diffusion light in the optical diffusion film of description references example 4 and its Luminance Distribution.

Figure 25: Figure 25 (a)～(j) is the figure providing for the expansion of the diffusion light in the optical diffusion film of comparative example 1 and its Luminance Distribution are described.

Figure 26: Figure 26 (a)～(k) is the figure providing for the expansion of the diffusion light in the optical diffusion film of comparative example 2 and its Luminance Distribution are described.

Figure 27: Figure 27 (a)～(h) is the figure providing for the expansion of the diffusion light in the optical diffusion film of comparative example 3 and its Luminance Distribution are described.

The figure that Figure 28: Figure 28 (a)～be (i) provides for the expansion of the diffusion light in the optical diffusion film of comparative example 4 and its Luminance Distribution are described.

Figure 29: Figure 29 (a)～(b) is the figure that to have used the reflective liquid crystal device of optical diffusion film in the past and provide in order to illustrate.

Embodiment

Embodiments of the present invention are manufacture methods of a kind of optical diffusion film, it is characterized in that, be to have for making incident light carry out the 1st structural region of anisotropic light diffusion and for making incident light carry out the manufacture method of optical diffusion film of the 2nd structural region of isotropy light diffusion, and comprise following operation (a)～(d):

(a) prepare the operation of composition for optical diffusion film;

Below, suitably with reference to accompanying drawing, illustrate embodiments of the present invention, but for above-mentioned explanation is easily understood, first, the light diffusion based on shutter region about in optical diffusion film and the ultimate principle of the diffusion of the light based on rod structure region are described.

1. ultimate principle

(1) diffusion of the light based on shutter

Fig. 1 (a) represents only to have shutter region and for making incident light carry out the vertical view (planimetric map) of the 1st structural region 10 of anisotropic light diffusion, Fig. 1 (b) represents the 1st structural region 10 shown in Fig. 1 (a) to cut off in vertical direction along dotted line A-A, the sectional view of the 1st structural region 10 while seeing section from the direction of arrow.

Should illustrate, in the present invention, anisotropy refers to, as shown in Fig. 2 (a)～(b), while having the diffusion of light tunicle, the spread condition (enlarged shape of diffusion light) of this light of the ejaculation light being diffused in the face parallel from film is because of the different and different character of the direction in this face.

More specifically, for the 1st structural region 10, mainly, the ejaculation light being diffused is in the face parallel with film, in the vertical direction of the direction of the shutter that light extends in the either direction with along along face, be diffused, so the enlarged shape of diffusion light is substantially oblong-shaped.

In addition, as shown in the planimetric map of Fig. 1 (a), and meanwhile the 1st structural region 10 have plate like region 12 that refractive index is higher and the lower plate like region 14 of refractive index along the either direction along face alternately configured in parallel extend the shutter 13 forming.

In addition, as shown in the sectional view of Fig. 1 (b), the plate like region 14 that the plate like region 12 that refractive index is higher and refractive index are lower has respectively specific thickness, also keeps the alternately state of configured in parallel in the vertical direction of the 1st structural region 10.

Thus, as shown in Fig. 2 (a)～(b), incident angle in light diffusion incident angle region time, is inferred incident light by the 1st structural region 10 diffusions.

; as shown in Fig. 1 (b); incident light to the incident angle of the 1st structural region 10 with respect to the boundary surface 13 of shutter 13 '; for the value in the angular range from parallel to regulation; that is,, while spreading the value in incident angle region for light, infer incident light (52,54) by the interior one side change of plate like region 12 direction of the high index of refraction in shutter region; along film thickness direction, pass on one side, thereby the direct of travel of the light of exiting surface side dissimilates.

Its result, incident angle is in light diffusion incident angle region time, infers incident light by the 1st structural region 10 diffusions (52 ', 54 ').

Should illustrate, as shown in Fig. 2 (a)～(b), Fig. 6 (a)～(b) and Fig. 7 (a)～(b), light diffusion incident angle region is according to the refringence in the shutter region in optical diffusion film, rod structure region, pitch angle etc. and the angular regions definite to each this optical diffusion film.

In addition, with regard to the incident direction of light variation of high-refractive-index regions 12 inside in shutter, except become as shown in Fig. 1 (b) pass through total reflection and linearly, change the situation of nyctitropic step-refraction index type zig-zag type, also can consider to become curved shape and change the situation of nyctitropic graded index type.

On the other hand, infer the incident light 56 of incident light when outer in light diffusion incident angle region to the incident angle of the 1st structural region 10 by the 1st structural region 10 diffusions, and directly through the 1st structural region 10(56 ').

According to above mechanism, the 1st structural region 10 that possesses shutter 13 for example, as shown in Fig. 2 (a)～(b), can be brought into play incident angle dependence in optical transmission and diffusion.

In addition, as shown in Fig. 2 (a)～(b), with regard to the 1st structural region, when the incident angle of incident light is contained in light diffusion incident angle region, even in the situation that this incident angle is different, also can carry out almost identical light diffusion in exiting surface side.

, use Fig. 3 (a) herein, illustrate that incident light is to the incident angle of the 1st structural region and by the relation of the opening angle of the diffusion light of the 1st structural region diffusion.

That is, Fig. 3 (a) represent to adopt incident light to the incident angle of the 1st structural region (°) as transverse axis, adopt by the opening angle of the diffusion light of the 1st structural region diffusion (°) family curve that forms as the longitudinal axis.

In addition, as shown in Figure 4, incidence angle θ 1 refers to, the angle when the angle of the 1st vertically incident of structural region 10 is made as to 0 ° (°).

More specifically, as mentioned above, the composition that contributes to the incident light of anisotropic light diffusion be mainly the shutter that extends with the either direction along face towards vertical composition, so while mentioning in the present invention " incidence angle θ 1 " of incident light, refer to the incident angle towards vertical composition of the shutter extending with the either direction along face.In addition, now, incidence angle θ 1 refer to angle when the angle of the light incident side normal to a surface with respect to optical diffusion film is made as to 0 ° (°).

In addition, the opening angle θ 2 of diffusion light from the literal opening angle that refers to diffusion light (°).

And the opening angle of diffusion light is larger, mean that the light with incident angle incident now more can be spread effectively by the 1st structural region.

On the contrary, the opening angle of diffusion light is less, means that the light with incident angle incident now more can directly see through the 1st structural region and not diffusion.

Should illustrate, for the concrete assay method of the opening angle of above-mentioned diffusion light, record in an embodiment.

; from the family curve as shown in Fig. 3 (a), can understand, if the 1st structural region, according to the difference of incident angle; the degree of optical transmission and diffusion differs widely, and can clearly light be spread to incident angle region and carry out separated with the incident angle region beyond it.

On the other hand, for not having the dependent film of incident angle, as shown in Figure 3 (b), the variation of incident angle can not give clear and definite impact to the degree of optical transmission and diffusion, cannot assert light diffusion incident angle region.

(2) diffusion of the light based on rod structure region

In addition, Fig. 5 (a) represents only to have rod structure region and for making incident light carry out the vertical view (planimetric map) of the 2nd structural region 20 of isotropy light diffusion, Fig. 5 (b) represents the 2nd structural region 20 shown in Fig. 5 (a) to cut off in vertical direction along dotted line A-A, the sectional view of the 2nd structural region 20 while seeing section from the direction of arrow.

Should illustrate, in the present invention, isotropy refers to, as shown in Fig. 6 (a)～(b), while thering is the diffusion of light tunicle, the character that the spread condition (enlarged shape of diffusion light) of this light of the ejaculation light being diffused in the face parallel with film does not change because of the direction in this face.

More specifically, for the 2nd structural region 20, the spread condition of the ejaculation light being diffused is rounded in the face parallel with film.

Herein, as shown in the planimetric map of Fig. 5 (a), the 2nd structural region 20 has the rod structure (22,24) consisting of relatively high column 22 Di relative to the refractive index region 24 of refractive index.

In addition, as shown in the sectional view of Fig. 5 (b), in the vertical direction of the 2nd structural region 20, column 22 Di relative to the refractive index region 24 that refractive index is relatively high becomes the state that has respectively the width of regulation and alternately configure.

Thus, as shown in Fig. 6 (a)～(b), incident angle in light diffusion incident angle region time, is inferred incident light by the 2nd structural region 20 diffusions.

; as shown in Fig. 5 (b); incident light to the incident angle of the 2nd structural region 20 with respect to the boundary surface 23 of rod structure 23 '; for the value in the angular range from parallel to regulation, that is, and while spreading the value in incident angle region for light; infer in the column 22 of the high index of refraction in rod structure region; incident light (62,64) on one side changes direction, and one passes along film thickness direction, thereby dissimilates at the direct of travel of the light of exiting surface side.

Its result, incident angle is in light diffusion incident angle region time, infers incident light and by the 2nd structural region 20, is spread (62 ', 64 ').

In addition, with regard to the incident direction of light in the column 22 of the high index of refraction in column structure region changes, except become as shown in Fig. 5 (b) pass through total reflection and linearly, change the situation of nyctitropic step-refraction index type zig-zag type, also can consider to become curved shape and change the situation of nyctitropic graded index type.

On the other hand, inferring the incident light 66 of incident light when outer in light diffusion incident angle region to the incident angle of the 2nd structural region 20 can be by the 2nd structural region 20 diffusion, and directly through the 2nd structural region 20(66 ').

According to above mechanism, the 2nd structural region 20 that possesses rod structure 23 for example, as shown in Fig. 6 (a)～(b), can be brought into play incident angle dependence in optical transmission and diffusion.

Should illustrate, with regard to incident light to the incident angle of the 2nd structural region with regard to the relation of the opening angle of the diffusion light of the 2nd structural region diffusion, identical with the situation in above-mentioned the 1st structural region, so omit explanation again.

2. basic comprising

Then, use accompanying drawing, the basic comprising of the optical diffusion film obtaining utilizing manufacture method of the present invention describes.

As shown in Fig. 7 (a)～(b), the feature of utilizing manufacture method of the present invention and obtaining optical diffusion film 30 is, have for making incident light carry out the shutter region (the 1st structural region) 10 of anisotropic light diffusion and for making incident light carry out the rod structure region (the 2nd structural region) 20 of isotropy light diffusion, preferably comprising successively these structural regions along film thickness direction on above-below direction.

Therefore, the optical diffusion film obtaining if utilize manufacture method of the present invention, for example, as shown in Figure 7 (a), by the incident angle dependence that the 1st and the 2nd structural region is had, carry out repetition, thereby can suppress the fluctuation of light diffusion property, obtain good incident angle dependence.

In addition, the optical diffusion film obtaining if utilize manufacture method of the present invention, for example, as shown in Figure 7 (b) shows, by the incident angle dependence that the 1st and the 2nd structural region is had, stagger, thus can be effectively and easily expand light diffusion incident angle region.

3. operation (a): the preparatory process of composition for optical diffusion film

Operation (a) is to prepare the operation of composition for the optical diffusion film of regulation.

More specifically, be preferably the different at least 2 kinds of polymerizable compounds of refractive index, Photoepolymerizationinitiater initiater and the operation of mixing according to other required and fixed adjuvant.

In addition, when mixing, can at room temperature directly stir, but from improving inhomogeneity viewpoint, for example, preferably under the heating condition of 40～80 ℃, stir.

In addition, also preferably further add diluting solvent to become the desirable viscosity that is applicable to application.

Below, for operation (a), carry out more specific description.

(1) high index of refraction polymerizable compound

(1)-a kind

In the different 2 kinds of polymerizable compounds of refractive index, the kind of the polymerizable compound that refractive index is relatively high (following, to be sometimes referred to as (A) composition) is not particularly limited, but preferably make its major component, is (methyl) acrylate that contains a plurality of aromatic rings.

Its reason is owing to inferring, as (A) composition, by containing specific (methyl) acrylate, thereby the polymerizable compound that the polymerization speed specific refractivity that makes (A) composition is relatively low is (following, be sometimes referred to as (B) composition) polymerization speed fast, make the polymerization speed between these compositions produce the poor of regulation, can effectively reduce the copolymerizable of two compositions.

Its result, while carrying out photocuring, can efficiency forms well by the part from (A) composition and the shutter region and the rod structure region that form from the part of (B) composition.

In addition, infer as (A) composition, by containing specific (methyl) acrylate, although thereby there is sufficient intermiscibility at monomer stage and (B) composition, but in polymerization process, in the stage of a plurality of connections, can make to be reduced to the intermiscibility of (B) composition the scope of regulation, further efficiency forms shutter region and rod structure region well.

And then, as (A) composition, by containing specific (methyl) acrylate, thereby can improve the refractive index of the part from (A) composition in shutter region and rod structure region, the specific refractivity of the part with from (B) composition is adjusted to the above value of regulation.

Therefore, as (A) composition, by containing specific (methyl) acrylate, thereby combine with the characteristic of (B) described later composition, can obtain efficiently possessing the shutter region that formed by the different part of refractive index and the optical diffusion film in rod structure region.

Should illustrate, " (methyl) acrylate that contains a plurality of aromatic rings " refers to, the ester residue of (methyl) acrylate partly has the compound of a plurality of aromatic rings.

In addition, " (methyl) acrylic acid " refer to acrylic acid and methacrylic acid the two.

In addition, (methyl) acrylate that contains a plurality of aromatic rings as this conduct (A) composition, for example can enumerate (methyl) biphenyl acrylate, (methyl) acrylic acid naphthalene ester, (methyl) acrylic acid anthracene ester, (methyl) acrylic acid benzyl phenyl ester, (methyl) acrylic acid xenyl oxygen base Arrcostab, (methyl) acrylic acid naphthyl oxygen base Arrcostab, (methyl) acrylic acid anthryl oxygen base Arrcostab, (methyl) acrylic acid benzyl phenyl oxygen base Arrcostab etc., or a part for the hydrogen atom on aromatic rings is by halogen, alkyl, alkoxy, the compound that haloalkyl etc. replace etc.

In addition, (methyl) acrylate that contains a plurality of aromatic rings for as (A) composition, preferably comprises the compound that contains cyclohexyl biphenyl, particularly preferably contains the biphenol compound being represented by following general formula (1).

(in general formula (1), R ¹～R ¹⁰independent separately, R ¹～R ¹⁰in at least one be the substituting group being represented by following general formula (2), all the other are any substituting group in hydrogen atom, hydroxyl, carboxyl, alkyl, alkoxy, haloalkyl, hydroxy alkyl, carboxyalkyl and halogen atom)

(in general formula (2), R ¹¹for hydrogen atom or methyl, the integer that carbon number n is 1～4, the integer that repeat number m is 1～10)

Its reason is owing to inferring, as (A) composition, by containing the biphenol compound with ad hoc structure, thereby can make (A) composition and (B) polymerization speed of composition produce the poor of regulation, make (A) composition and (B) intermiscibility of composition be reduced to the scope of regulation, can reduce by two compositions copolymerizable each other.

In addition, can improve the refractive index of the part from (A) composition in shutter region and rod structure region, more easily the specific refractivity of the part with from (B) composition is adjusted to the above value of regulation.

In addition, the R in general formula (1) ¹～R ¹⁰while containing any in alkyl, alkoxy, haloalkyl, hydroxy alkyl and carboxyalkyl, the value in the scope that the carbon number that preferably makes its moieties is 1～4.

Its reason be due to, if above-mentioned carbon number is for surpassing 4 value, the polymerization speed of (A) composition reduces or too reduces from the refractive index of the part of (A) composition, is sometimes difficult to form efficiently shutter region and rod structure region.

Therefore, the R in general formula (1) ¹～R ¹⁰while containing any in alkyl, alkoxy, haloalkyl, hydroxy alkyl and carboxyalkyl, the value in the scope that the carbon number that more preferably makes its moieties is 1～3, the more preferably value in 1～2 scope.

In addition, the R in general formula (1) ¹～R ¹⁰be preferably haloalkyl or halogen atom substituting group in addition, that is, do not contain the substituting group of halogen.

Its reason be due to, prevent from producing two when burning optical diffusion film etc.

english, from the viewpoint of environmental protection and preferably.

Should illustrate, in the optical diffusion film that possesses shutter region etc. in the past, while obtaining the shutter region etc. of regulation, for the object that makes monomer component high index of refraction, conventionally in monomer component, carry out halogen replacement.

In this respect, if the biphenol compound being represented by general formula (1), even if do not carry out halogen replacement, also can form high refractive index.

Therefore, if even the optical diffusion film that the optical diffusion film in the present invention is formed with composition photocuring, while not containing halogen, also can be brought into play good incident angle dependence.

In addition, the R in general formula (1) ²～R ⁹in any be preferably the substituting group being represented by general formula (2).

Its reason be due to, by making the substituent position being represented by general formula (2), be R ¹and R ¹⁰position in addition, thus can effectively prevent that stage (A) composition before carrying out photocuring is orientated and crystallization each other.

And then, carrying out photocuring monomer stage before for liquid, even if do not use diluting solvent etc., also can on apparent, evenly mix with (B) composition.

Thus, in the stage of photocuring, can occur (A) composition and (B) composition the condensing, be separated of trickle level, can obtain more efficiently possessing the optical diffusion film in shutter region and rod structure region.

And then, from identical viewpoint, the R in general formula (1) ³, R ⁵, R ⁶and R ⁸in any be particularly preferably the substituting group being represented by general formula (2).

In addition, the integer that the repeat number m in the substituting group that conventionally preferably makes to be represented by general formula (2) is 1～10.

Its reason be due to, if repeat number m is for surpassing 10 value, the oxyalkylene chain that connects polymerization position and cyclohexyl biphenyl becomes long, sometimes hinders (A) composition polymerization each other in polymerization position.

Therefore, the integer that the substituent repeat number m that more preferably makes to be represented by general formula (2) is 1～4, is particularly preferably 1～2 integer.

Should illustrate, from identical viewpoint, the integer that the substituent carbon number n that conventionally preferably makes to be represented by general formula (2) is 1～4.

In addition, if consider that, cyclohexyl biphenyl excessively near with respect to cyclohexyl biphenyl as the position of the polymerism carbon-to-carbon double bond at polymerization position becomes situation sterically hindered and that the polymerization speed of (A) composition is reduced, the integer that the substituent carbon number n that more preferably makes to be represented by general formula (2) is 2～4, is particularly preferably 2～3 integer.

In addition, as the concrete example of the biphenol compound being represented by general formula (1), can preferably enumerate the compound being represented by following formula (3)～(4).

(1)-2 molecular weight

In addition, the value in the scope that the molecular weight that preferably makes (A) composition is 200～2500.

Its reason is owing to inferring, and by the scope that makes the molecular weight of (A) composition be regulation, can further accelerate the polymerization speed of (A) composition, more effectively reduction (A) composition and (B) copolymerizable of composition.

Its result, while carrying out photocuring, can form more efficiently by the part from (A) composition and the shutter region and the rod structure region that form from the part of (B) composition.

That is, if (A) molecular weight of composition is to be less than 200 value,, because the sterically hindered polymerization speed that causes reduces, becomes and approach with the polymerization speed of (B) composition, sometimes easily produce and (B) copolymerization of composition.On the other hand, if (A) molecular weight of composition is for surpassing 2500 value, the difference along with the molecular weight with (B) composition diminishes, (A) polymerization speed of composition reduces, become and approach with the polymerization speed of (B) composition, infer easy generation and (B) copolymerization of composition, its result, is sometimes difficult to efficiency and forms well shutter region and rod structure region.

Therefore, the value in the scope that the molecular weight that more preferably makes (A) composition is 240～1500, the more preferably value in 260～1000 scope.

Should illustrate, with regard to the molecular weight of (A) composition, can, according to being tried to achieve by the calculated value that the atomic weight with constituting atom obtains that forms of molecule, also can use gel permeation chromatography (GPC) to measure weight-average molecular weight.

(1)-3 use separately

In addition, the optical diffusion film in the present invention is to contain (A) composition as the monomer component that is formed on shutter region and the relative high part of refractive index in rod structure region by the feature of composition, but preferably with single composition, contains (A) composition.

Its reason be due to, by such formation, thereby can effectively suppress the part from (A) composition, in other words, the fluctuation of the refractive index in the relatively high part of refractive index, obtains possessing the optical diffusion film in shutter region and rod structure region more efficiently.

; (B) when composition is low with respect to the intermiscibility of (A) composition, for example, when (A) composition is halogen based compound etc.; sometimes and for example, with other (A) composition (, non-halogen based compound etc.) as being used for making (A) composition and the 3rd composition that (B) composition mixes.

Yet, now, due to the impact of above-mentioned the 3rd composition, cause sometimes from the refractive index generation of the relatively high part of the refractive index of (A) composition, fluctuating or easily reducing.

Its result, sometimes becomes inhomogeneous or easily excessively reduces with the refringence of the relative low part of refractive index from (B) composition.

Therefore, preferably select to have the monomer component with the high index of refraction of the intermiscibility of (B) composition, and used as independent (A) composition.

Should illustrate, for example, if as the biphenol compound being represented by formula (3) of (A) composition, owing to being low viscosity, so there is the intermiscibility with (B) composition, therefore can use as independent (A) composition.

(1)-4 refractive indexes

In addition, the value in the scope that the refractive index that preferably makes (A) composition is 1.5～1.65.

Its reason be due to, by making the refractive index of (A) composition, it is the value in above-mentioned scope, thereby can more easily regulate the specific refractivity with part from (B) composition from the refractive index of the part of (A) composition, obtain more efficiently possessing the optical diffusion film in shutter region and rod structure region.

That is, if (A) refractive index of composition is to be less than 1.5 value, become too small with the specific refractivity of (B) composition, be sometimes difficult to obtain desirable incident angle dependence.On the other hand, if (A) refractive index of composition is for surpassing 1.65 value, although become large with the specific refractivity of (B) composition, sometimes with (B) composition apparent on the state that mixes be also difficult to form.

Therefore, the value in the scope that the refractive index that more preferably makes (A) composition is 1.52～1.62, the more preferably value in 1.56～1.6 scope.

Should illustrate, the refractive index of above-mentioned (A) composition refers to, utilizes irradiation to be cured the refractive index of previous (A) composition.

In addition, refractive index for example can be measured according to JIS K0062.

(1)-5 content

In addition, preferably making optical diffusion film is the value in the scope of 25～400 weight portions with (B) composition 100 weight portions of the content of (A) composition in the composition polymerizable compound relatively low with respect to refractive index described later.

Its reason be due to, if (A) content of composition is the value that is less than 25 weight portions, (A) composition tails off with respect to the ratio that exists of (B) composition, width from the part of (A) composition, in other words, the width of plate like region, the width of column are compared excessively and are diminished with the width of part from (B) composition, are sometimes difficult to obtain having good incident angle dependent shutter region and rod structure region.In addition, the shutter region on the thickness direction of optical diffusion film and the thickness in rod structure region become insufficient, sometimes display light diffusivity not.On the other hand, if (A) content of composition is for surpassing the value of 400 weight portions, (A) composition becomes many with respect to the ratio that exists of (B) composition, from the width of the part of (A) composition and the width of part from (B) composition, compare excessive change large, be sometimes difficult on the contrary obtain having good incident angle dependent shutter region and rod structure region.In addition, the shutter region of the thickness direction of optical diffusion film and the thickness in rod structure region become insufficient, sometimes display light diffusivity not.

Therefore, the content that more preferably makes (A) composition is the value in the scope of 40～300 weight portions, the more preferably value in the scope of 50～200 weight portions with respect to (B) composition 100 weight portions.

(2) low-refraction polymerizable compound

(2)-a kind

In the different 2 kinds of polymerizable compounds of refractive index; the kind of the polymerizable compound that refractive index is relatively low ((B) composition) is not particularly limited; as its major component; such as enumerating urethane (methyl) acrylate, there are (methyl) acrylic acid series polymeric compounds of (methyl) acryloyl group, the organic siliconresin that contains (methyl) acryloyl group, unsaturated polyester resin etc. at side chain, but be particularly preferably urethane (methyl) acrylate.

Its reason be due to, if urethane (methyl) acrylate, not only can more easily regulate the specific refractivity with part from (B) composition from the refractive index of the part of (A) composition, can also effectively suppress the fluctuation from the refractive index of the part of (B) composition, obtain more efficiently possessing the optical diffusion film in shutter region and rod structure region.

Therefore, below, mainly for urethane (methyl) acrylate as (B) composition, describe.

Should illustrate, (methyl) acrylate refer to acrylate and methacrylate the two.

First, urethane (methyl) acrylate by (B1) at least contain the compound, (B2) polyol compound of 2 isocyanate group and (B3) (methyl) acrylic acid hydroxyalkyl acrylate form, wherein, (B2) preferably diatomic alcohol compounds, particularly preferably poly alkylene glycol.

Should illustrate, (B) in composition, also contain the oligomer of the repetitive with urethane bond.

Wherein, as (B1) composition, at least contain the compound of 2 isocyanate group, for example can enumerate 2, 4-toluene diisocyanate, 2, 6-toluene diisocyanate, 1, 3-XDI, 1, the aromatic poly-isocyanates such as 4-XDI, the aliphatic polymeric isocyanates such as hexamethylene diisocyanate, isophorone diisocyanate (IPDI), the ester ring type polyisocyanates such as hydrogenated diphenyl methane diisocyanate, and their biuret body, isocyanuric acid ester body, and conduct and ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, the adduct of the reactant of the low molecule active hydrogen-contg compound of castor-oil plant wet goods (for example, XDI is three-functionality-degree adduct) etc.

In addition, above-mentioned in, be particularly preferably ester ring type polyisocyanate.

Its reason be due to, ester ring type polyisocyanate, compares with aliphatic polymeric isocyanate if, due to relations such as space conformations, easily the reaction velocity of each isocyanate group is arranged to difference.

Thus, can suppress that (B1) composition only reacts with (B2) composition or (B1) composition only react with (B3) composition, make (B1) composition and (B2) composition and (B3) composition react reliably, can prevent the generation of unnecessary accessory substance.

Its result, can suppress the part from (B) composition in shutter region and rod structure region effectively, that is, and and the fluctuation of the refractive index of low-refraction part.

In addition, ester ring type polyisocyanate, compares with aromatic poly-isocyanate if, can make resulting (B) composition and (A) intermiscibility of composition be reduced to the scope of regulation, forms more efficiently shutter region and rod structure region.

And then, if ester ring type polyisocyanate, compare with aromatic poly-isocyanate, the refractive index of (B) composition that can reduce to obtain, so increase and (A) specific refractivity of composition, further efficiency forms shutter region and the rod structure region of incident angle dependence excellence well.

In addition, in such ester ring type polyisocyanate, preferably only contain the ester ring type diisocyanate of 2 isocyanate group.

Its reason be due to, if ester ring type diisocyanate, can and (B3) react with (B2) composition component quantifying, obtain single (B) composition.

As such ester ring type diisocyanate, can particularly preferably enumerate isophorone diisocyanate (IPDI).

Its reason be due to, can effective difference be set to the reactivity of 2 isocyanate group.

In addition, in forming the composition of urethane (methyl) acrylate, as the poly alkylene glycol of (B2) composition, such as enumerating polyglycol, polypropylene glycol, polytetramethylene glycol, poly-hexanediol etc., wherein, be particularly preferably polypropylene glycol.

Its reason be due to, if polypropylene glycol, viscosity is low, so can carry out solvent-free processing.

In addition, if polypropylene glycol, while making (B) composition solidify, becomes the good soft chain segment in this solidfied material, can effectively improve the operability of optical diffusion film, installation property.

Should illustrate, (B) weight-average molecular weight of composition can mainly be passed through the weight-average molecular weight adjusting of (B2) composition.Herein, (B2) weight-average molecular weight of composition is generally 2300～19500, is preferably 4300～14300, is particularly preferably 6300～12300.

In addition, in forming the composition of urethane (methyl) acrylate, as (B3) composition, be (methyl) acrylic acid hydroxyalkyl acrylate, such as enumerating (methyl) acrylic acid 2-hydroxy methacrylate, (methyl) acrylic acid 2-hydroxy propyl ester, (methyl) acrylic acid 3-hydroxy propyl ester, (methyl) acrylic acid 2-hydroxyl butyl ester, (methyl) acrylic acid 3-hydroxyl butyl ester, (methyl) acrylic acid 4-hydroxyl butyl ester etc.

In addition, from reducing the polymerization speed of resulting urethane (methyl) acrylate, form more efficiently the shutter region of regulation and the viewpoint in rod structure region and set out, particularly more preferably methacrylic acid hydroxyl Arrcostab, more preferably 2-hydroxyethyl methacrylate.

In addition, utilize the synthetic of urethane (methyl) acrylate that (B1)～(B3) composition carries out to implement according to conventional methods.

Now, preferably make (B1)～(B3) mixing ratio of composition be take molar ratio computing as (B1) composition: (B2) composition: (B3) ratio of composition=1～5:1:1～5.

Its reason be due to, by being above-mentioned mixing ratio, thereby can synthesize efficiently that 2 hydroxyls that 1 isocyanate group that (B1) composition has has with (B2) composition react respectively and bonding and then urethane (methyl) acrylate that (B3) another isocyanates radical reaction that hydroxyl that composition has and 2 (B1) compositions have respectively bonding form.

Therefore, more preferably make (B1)～(B3) mixing ratio of composition be take molar ratio computing as (B1) composition: (B2) composition: (B3) ratio of composition=1～3:1:1～3, the more preferably ratio of 2:1:2.

(2)-2 weight-average molecular weight

In addition, the value in the scope that the weight-average molecular weight that preferably makes (B) composition is 3000～20000.

Its reason is due to, the scope that the weight-average molecular weight by making (B) composition is regulation, can make (A) composition and (B) polymerization speed of composition produce the poor of regulation, effectively reduce the copolymerizable of two compositions.

; if (B) weight-average molecular weight of composition is to be less than 3000 value, the polymerization speed of (B) composition accelerates, and becomes and approaches with the polymerization speed of (A) composition; easily produce and (A) copolymerization of composition, result is sometimes difficult to efficiency and forms well shutter region and rod structure region.On the other hand, if (B) weight-average molecular weight of composition is for surpassing 20000 value, is sometimes difficult to form the shutter region being formed by the part from (A) composition and (B) composition and excessively reduces and become to analyze in the coating stage (A) with rod structure region or with the intermiscibility of (A) composition.

Therefore, the value in the scope that the weight-average molecular weight that more preferably makes (B) composition is 5000～15000, the more preferably value in 7000～13000 scope.

Should illustrate, (B) weight-average molecular weight of composition can be used gel permeation chromatography (GPC) to measure.

(2)-3 use separately

In addition, (B) composition can be used together different two or more of molecular structure, weight-average molecular weight, but from suppressing the viewpoint of fluctuation of the refractive index of the part from (B) composition shutter region and rod structure region, preferably only uses a kind.

; while using multiple (B) composition; from the refractive index in the relatively low part of the refractive index of (B) composition, produce fluctuation or uprise, sometimes become inhomogeneous or excessively reduce with the refringence of the relative high part of refractive index from (A) composition.

(2)-4 refractive indexes

In addition, the value in the scope that the refractive index that preferably makes (B) composition is 1.4～1.55.

Its reason be due to, by making the refractive index of (B) composition, it is the value in above-mentioned scope, thereby can more easily regulate the specific refractivity with part from (B) composition from the refractive index of the part of (A) composition, obtain more efficiently possessing the optical diffusion film in shutter region and rod structure region.

That is,, if (B) refractive index of composition is to be less than 1.4 value, although become large with the specific refractivity of (A) composition, the intermiscibility extreme variation with (A) composition, possibly cannot form shutter region and rod structure region.On the other hand, if (B) refractive index of composition, for surpassing 1.55 value, becomes too small with the specific refractivity of (A) composition, be sometimes difficult to obtain desirable incident angle dependence.

Therefore, the value in the scope that the refractive index that more preferably makes (B) composition is 1.45～1.54, the more preferably value in 1.46～1.52 scope.

Should illustrate, the refractive index of above-mentioned (B) composition refers to the refractive index of utilizing irradiation to be cured previous (B) composition.

And refractive index for example can be measured according to JIS K0062.

In addition, preferably making the refractive index of above-mentioned (A) composition and (B) specific refractivity of composition is more than 0.01 value.

Its reason be due to, by making above-mentioned specific refractivity for the value in the scope of regulation, thereby can access the optical diffusion film that the better incident angle dependence that has in optical transmission and diffusion and wider light spread incident angle region.

That is, if above-mentioned specific refractivity is to be less than 0.01 value, incident light becomes narrow in the angle domain of shutter region and the inner total reflection of rod structure region, so there is the opening angle of time diffusion excessively to narrow down.On the other hand, if above-mentioned specific refractivity is excessive large value, the intermiscibility of (A) composition and (B) composition variation too, likely cannot form shutter region and rod structure region.

Therefore, more preferably make the value in the refractive index of (A) composition and scope that (B) specific refractivity of composition is 0.05～0.5, more preferably the value in 0.1～0.2 scope.

Should illustrate, herein so-called (A) composition and (B) refractive index of composition refer to, utilize (A) composition before being cured of irradiation and (B) refractive index of composition.

(2)-5 content

In addition, preferably making optical diffusion film is the value in the scope of 10～80 % by weight by total amount 100 % by weight of composition with respect to optical diffusion film with the content of (B) composition in composition.

Its reason be due to, if (B) content of composition is the value that is less than 10 % by weight, (B) composition tails off with respect to the ratio that exists of (A) composition, from the width of the part of (B) composition, compare excessively and diminish with the width of part from (A) composition, be sometimes difficult to obtain having good incident angle dependent shutter region and rod structure region.In addition, the shutter region on the thickness direction of optical diffusion film and the thickness in rod structure region become insufficient sometimes.On the other hand, if (B) content of composition is for surpassing the value of 80 % by weight, (B) composition becomes many with respect to the ratio that exists of (A) composition, from the width of the part of (B) composition and the width of part from (A) composition, compare excessive change large, be sometimes difficult on the contrary obtain having good incident angle dependent shutter region and rod structure region.In addition, the shutter region on the thickness direction of optical diffusion film and the thickness in rod structure region become insufficient sometimes.

Therefore, the content that more preferably makes (B) composition is the value in the scope of 20～70 % by weight, the more preferably value in the scope of 30～60 % by weight by total amount 100 % by weight of composition with respect to optical diffusion film.

(3) Photoepolymerizationinitiater initiater

In addition, optical diffusion film in the present invention, with in composition, according to required, preferably contains Photoepolymerizationinitiater initiater as (C) composition.

Its reason be due to, by containing Photoepolymerizationinitiater initiater, thereby when optical diffusion film is irradiated to active energy ray with composition, can form efficiently shutter region and rod structure region.

Herein, Photoepolymerizationinitiater initiater refers to the compound that produces free radical kind by the irradiation of ultraviolet isoreactivity energy line.

As above-mentioned Photoepolymerizationinitiater initiater, for example, can enumerate benzoin, benzoin methylether, benzoin ethyl ether, benzoin iso-propylether, benzoin n-butylether, benzoin isobutyl ether, acetophenone, dimethylamino acetophenone, 2,2-dimethoxy-2-phenyl acetophenone, 2,2-diethoxy-2-phenyl acetophenone, 2-hydroxy-2-methyl-1-phenyl-propane-1-ketone, 1-hydroxycyclohexylphenylketone, 2-methyl isophthalic acid-and 4-(methyl mercapto) phenyl ］-2-morpholinyl-propane-1-ketone, 4-(2-hydroxyl-oxethyl) phenyl-2-(hydroxyl-2-propyl group) ketone, benzophenone, to phenyl benzophenone, 4,4-diethylamino benzophenone, dichloro benzophenone, 2-methylanthraquinone, 2-EAQ, 2-tert-butyl group anthraquinone, 2-amino anthraquinones, 2-methyl thioxanthones, 2-ethyl thioxanthones, CTX, 2,4-dimethyl thioxanthones, 2,4-diethyl thioxanthone, benzil dimethyl ketal, acetophenone dimethyl ketal, to dimethylamine benzoic ether, few 2-hydroxy-2-methyl-1-4-(1-methyl ethylene) and phenyl ］ propane ］ etc., can use separately wherein a kind, also can combine two or more use.

Should illustrate, content when containing Photoepolymerizationinitiater initiater, preferably with respect to (A) composition and (B) total metering 100 weight portions of composition be the value in the scope of 0.2～20 weight portion, the more preferably value in the scope of 0.5～15 weight portion, the more preferably value in the scope of 1～10 weight portion.

(4) other adjuvant

In addition, in not damaging the scope of effect of the present invention, can suitably add above-claimed cpd adjuvant in addition.

As such adjuvant, such as enumerating antioxidant, ultraviolet light absorber, antistatic agent, polymerization accelerant, polymerization inhibitor, infrared absorbent, plastifier, diluting solvent and levelling agent etc.

Should illustrate, the content of such adjuvant, conventionally preferably with respect to (A) composition and (B) total metering 100 weight portions of composition be the value in the scope of 0.01～5 weight portion, the more preferably value in the scope of 0.02～3 weight portion, the more preferably value in the scope of 0.05～2 weight portion.

4. operation (b): painting process

As shown in Figure 8 (a), operation (b) is the optical diffusion film composition that 2 coatings are prepared for technique sheet material, forms the operation of coating layer 1.

As technique sheet material, can use any in plastic foil, paper.

Wherein, as plastic foil, can enumerate the polyester mesenterys such as polyethylene terephthalate film, the polyolefin mesenterys such as polyethylene film, polypropylene screen, the cellulose mesenterys such as tri acetyl cellulose membrane, and polyimide mesentery etc.

In addition, as paper, such as enumerating viscose paper, coated paper and laminated paper etc.

In addition, if consider operation described later, preferably to the film of the excellent in dimensional stability of heat, active energy ray as technique sheet material 2.

As such film, in above-mentioned plastic foil, can preferably enumerate polyester mesentery, polyolefin mesentery and polyimide mesentery.

In addition, technique sheet material is carried out after photocuring, for the optical diffusion film that makes to obtain, easily from technique sheet material, peel off, preferably the coated face side of the optical diffusion film composition in technique sheet material arranges peel ply.

Above-mentioned peel ply can be used the known remover formation in the past such as silicon-type remover, fluorine series stripping agent, alkyd series stripping agent, ethylene series remover.

Should illustrate, the thickness of technique sheet material is preferably the value in the scope of 25～200 μ m conventionally.

In addition, as be coated with the method for optical diffusion film composition on technique sheet material, such as can utilize scraper for coating method, rolling method, excellent painting method, scraper plate rubbing method, mould be coated with method and intaglio plate rubbing method etc. in the past known method carry out.

Should illustrate, now, the thickness that preferably makes coating layer is the value in the scope of 100～700 μ m.

5. operation (c): the 1st active energy ray irradiation process

Operation (c) is coating layer to be carried out to the 1st active energy ray irradiate, below coating layer, part forms and in the either direction along face, alternately to configure as the different a plurality of plate like region of the refractive index of the 1st structural region the shutter region forming, and in the residual operation that does not form the region of shutter of upper section of coating layer.

That is, as shown in Figure 8 (b) shows, for the coating layer 1 being formed on technique sheet material 2, irradiate the active energy ray 50 only being formed by the controlled direct light of irradiating angle.

More specifically, for example, as shown in Fig. 9 (a), by the UV-lamp 125 to wire, be for example provided with ultraviolet lamp 120(that cold mirror 122 that optically focused uses forms, commercially available product if, WeiEYE GRAPHICS Co., Ltd. system, ECS-4011GX etc.) in configuration heat radiation cut-off filter 121 and shadow shield 123, thereby take out the active energy ray 50 only being formed by the controlled direct light of irradiating angle, and the coating layer 1 being formed on technique sheet material 2 is irradiated.

Should illustrate, with regard to the UV-lamp of wire, normally using the parallel direction of the long side direction of technique sheet material 2 with thering is coating layer 1 as benchmark (0 °), become the value in the scope of-80～80 °, preferably become the value in the scope of-50～50 °, particularly preferably become that the mode of the value in the scope of-30～30 ° arranges.

Using the reason of linear light source herein, is due to can be efficiently and stably manufacture plate like region that refractive index is different and alternately and with respect to film thickness direction using the shutter region as the 1st structural region that constant pitch angle configured in parallel forms.

More specifically, by using linear light source, thereby can irradiate, when the axis direction of linear light source is seen, be essentially directional light and be nonparallel light while seeing from the vertical direction of the axis direction with linear light source.

Now, as shown in Figure 9 (b), as the irradiating angle that irradiates light, the irradiating angle θ 3 while conventionally preferably making the angle of the normal to a surface with respect to coating layer 1 be made as 0 ° is the value in the scope of-80～80 °.

Its reason be due to, if irradiating angle is the extraneous value of-80～80 °, the impact of the surperficial reflection of coating layer 1 etc. becomes large, is sometimes difficult to form sufficient shutter region.

In addition, irradiating angle θ 3 preferably has width (irradiating angle width) θ 3 ' of 1～80 °.

Its reason be due to, if for to be less than the value of 1 °, the interval in shutter region becomes narrow to above-mentioned irradiating angle width θ 3 ', be sometimes difficult to obtain desirable the 1st structural region.On the other hand, if above-mentioned irradiating angle width θ 3 ' is for surpassing the value of 80 °, irradiating light too disperses, and is sometimes difficult to form shutter region.

Therefore, the irradiating angle θ 3 ' that more preferably makes irradiating angle θ 3 is the value in the scope of 2～45 °, the more preferably value in the scope of 5～20 °.

In addition, as irradiating light, can enumerate ultraviolet ray, electron beam etc., preferably use ultraviolet ray.

Its reason be due to, during for electron beam, polymerization speed is very fast, so (A) composition cannot be fully separated with (B) composition in polymerization process, is sometimes difficult to form shutter region.On the other hand, with visible ray etc. relatively time, for ultraviolet ray, curing ultraviolet curable resin, the abundant species of spendable Photoepolymerizationinitiater initiater by its irradiation, so can expand (A) composition and (B) range of choice of composition.

In addition, as ultraviolet irradiation condition, preferably making the peak illumination at painting layer surface is 0.01～50mW/cm ²scope in value.

Its reason be due to, if peak illumination is for being less than 0.01mW/cm ²value, although can fully not form the region of shutter, be sometimes difficult to form clearly shutter region.On the other hand, if peak illumination is for surpassing 50mW/cm ²value, (A) composition and (B) composition solidify being separated before carrying out, be sometimes difficult on the contrary form clearly shutter region.

Therefore, more preferably making the ultraviolet peak illumination of painting layer surface is 0.05～20mW/cm ²scope in value.0.1～10mW/cm more preferably ²scope in value.

Should illustrate, so-called peak illumination refers to herein, shows the measured value of peaked part at the active energy ray that is irradiated to painting layer surface.

In addition, preferably make to be formed on coating layer on technique sheet material and move the ultraviolet illuminated portion by utilizing ultraviolet lamp to irradiate with the speed of 0.1～10m/ minute.

Its reason be due to, if above-mentioned speed is to be less than the value of 0.1m/ minute, production excessively reduces sometimes.On the other hand, if above-mentioned speed is for surpassing the value of 10m/ minute,, than the solidifying of coating layer, in other words, fast than the formation in shutter region, ultraviolet ray changes the incident angle of coating layer, and the formation in shutter region sometimes becomes insufficient.

Therefore, more preferably the coating layer that makes to be formed on technique sheet material moves the ultraviolet illuminated portion by utilizing ultraviolet lamp to irradiate with the speed in the scope of 0.2～5m/ minute, further preferably with the speed in the scope of 0.5～3m/ minute, passes through.

6. operation (d): the 2nd active energy ray irradiation process

Operation (d) is coating layer further to be carried out to the 2nd active energy ray irradiate, in the region that does not form shutter, form the rod structure region that makes the relatively much higher column of refractive index stand in great numbers and form as the 2nd structural region in the relative Di of refractive index region, wherein, as the 2nd active energy ray, irradiate, for coating layer, be situated between and irradiate the operation from the irradiation light of linear light source by irradiating parallel light parts.

; for example, as shown in Figure 10 (a)～(b), utilize and irradiate parallel light parts 200(200a, 200b); make to form the high directional light 60 of the depth of parallelism from the irradiation light 50 of linear light source 125, and it is irradiated the coating layer (10,10 ') being formed on technique sheet material 2.

In addition, while carrying out the irradiation of this directional light, can directly to coating layer, irradiate, but also preferably at the stacked stripping film of the painting layer surface exposing, across stripping film, irradiate.

Now, as stripping film, can, in the above-mentioned technique sheet material of being recorded as technique sheet material, suitably select to have the technique sheet material of ultraviolet (uv) transmission.

Herein, with regard to the direct light being produced by linear light source irradiating with regard to the 1st active energy ray as being used to form shutter region, in this direction of light direction vertical with the axis direction of linear light source, there is no expansion, and almost parallel, but in the parallel direction of the axis direction with linear light source, light towards there is no unitarity but random.

On the other hand, Jie of irradiating with regard to the 2nd active energy ray as being used to form rod structure region by irradiate that parallel light parts irradiate from regard to the irradiation light of linear light source, the direction of light being issued is the light of the almost parallel that there is no expansion, i.e. directional light when any direction is seen.

Should illustrate, as shown in Figure 10 (c), with regard to irradiating parallel light parts 200, in the direct light being produced by linear light source 125, be in the parallel direction of the axis direction of random linear light source 125 with direction of light, for example, by using the light-blocking members 210 such as plate-shaped member 210a, cartridge 210b to make direction of light unified, thereby can make the direct light being produced by linear light source 125 change directional light into.

More specifically, in the direct light being produced by linear light source 125, with respect to the low light of the depth of parallelism of the light-blocking members 210 such as plate-shaped member 210a, cartridge 210b, contact and be absorbed with them.

Therefore, only with respect to the high light of the depth of parallelism of the light-blocking members 210 such as plate-shaped member 210a, cartridge 210b, i.e. directional light, by irradiating parallel light parts 200, thereby the illuminated parallel light parts 200 of the direct light as a result of, being produced by linear light source 125 change directional light into.

In addition, as long as the irradiation parallel light parts that use in the present invention can change the irradiation light from linear light source into directional light that the depth of parallelism is high, just be not particularly limited, but be preferably as shown in Figure 10 (a) shows a plurality of plate-shaped member 210a irradiation parallel light parts 200a that configured in parallel forms respectively when forming and seeing from film top by a plurality of plate-shaped member 210a.

Its reason is due to, irradiation parallel light parts 200a if so,, in the 2nd active energy ray irradiates, can easily the irradiation light from linear light source 125 be changed into the directional light of the depth of parallelism with regulation.

That is, by by a plurality of plate-shaped member 210a configured in parallel simply, thereby can easily change the direct light being produced by linear light source 125 into directional light.

In addition, as shown in Figure 11 (a) shows, the value in the scope that the interval L1 that preferably makes a plurality of plate-shaped member 210a is 1～100mm.

Its reason be due to, by making the interval L1 of a plurality of plate-shaped member 210a, be the value in above-mentioned scope, thereby in the 2nd active energy ray irradiates, can more efficiently the irradiation light from linear light source 125 be changed into the directional light of the depth of parallelism with regulation.

That is, if the interval L1 of a plurality of plate-shaped member 210a is the value that is less than 1mm, the quantity of plate-shaped member 210a excessively becomes many, and the irradiation light sometimes hindering from linear light source 125 arrives coating layer (10,10 ').On the other hand, if the interval L1 of a plurality of plate-shaped member 210a for surpassing the value of 100mm, makes the unified overaction reduction of direct of travel from the irradiation light of linear light source 125, be sometimes difficult to change to the directional light with the depth of parallelism of regulation.

Therefore, the value in the scope that the interval L1 that more preferably makes a plurality of plate-shaped member 210a is 5～75mm, the more preferably value in the scope of 10～50mm.

Should illustrate, Figure 11 (a) is from film top 10(a with the aid of pictures) shown in the vertical view (planimetric map) of irradiation parallel light parts 200a.

In addition, the width L2 of plate-shaped member 210a is not particularly limited, but is conventionally preferably the value in the scope of 10～1000mm, the more preferably value in the scope of 50～500mm.

Should illustrate, the diameter of the axis direction of linear light source 125 is preferably the value in the scope of 5～100mm conventionally.

In addition, for the thickness of plate-shaped member 210a, be also not particularly limited, be conventionally preferably the value in the scope of 0.1～5mm, more preferably the value in the scope of 0.5～2mm.

And then, for the material substance of plate-shaped member 210a, as long as can absorb the light low with respect to the depth of parallelism of plate-shaped member 210a, be just also not particularly limited, for example, can use (ALSTAR) steel plate etc. of aluminizing of having implemented heat-resisting black application.

In addition, preferably at the Axis Cross of plate-shaped member and linear light source, towards configuration, irradiate parallel light parts 200a.

And then, as shown in Figure 11 (a) shows, while more preferably seeing from film top, the axis direction quadrature of plate-shaped member 210a and linear light source 125 towards, that is, and become θ 4=90 ° towards configuration irradiation parallel light parts 200a.

Its reason be due to, by such configuration, irradiate parallel light parts 200a, thereby in the 2nd active energy ray irradiates, can further efficiently the irradiation light from linear light source 125 be changed into the directional light of the depth of parallelism with regulation.

That is, by such configuration, irradiate parallel light parts 200a, thus in the direct light being produced by linear light source 125, in the parallel direction of the axis direction of the linear light source 125 random with being oriented of light, can be more efficiently by light towards unification.

In addition, as the irradiation parallel light parts that use in the present invention, be preferably the irradiation parallel light parts 200b of the aggregate of a plurality of cartridge 210b of conduct as shown in Figure 10 (b).

Its reason is due to, irradiation parallel light parts 200b if so,, in the 2nd active energy ray irradiates, can more easily the irradiation light from linear light source 125 be changed into the directional light of the depth of parallelism with regulation.

That is, the direct of travel of the irradiation light being produced by linear light source 125, in the vertical direction of the axis direction with linear light source 125, is unified into almost parallel substantially, but also exist, has situation about expanding a little.

In this respect, irradiation parallel light parts 200b if so, even in the vertical direction of the axis direction with linear light source 125, also can by light towards unification, so can change the direct light being produced by linear light source 125 into directional light that the depth of parallelism is higher.

In addition, as shown in Figure 12 (a)～(d), preferably make cartridge 210b(210b ', 210b ' ', 210b ' ' ', 210b ' ' ' ') maximum gauge L3(L3 ', L3 ' ', L3 ' ' ', L3 ' ' ' ') be the value in the scope of 1～100mm.

Its reason be due to, by making the maximum gauge L3 of cartridge 210b, be the value in above-mentioned scope, thereby in the 2nd active energy ray irradiates, can more efficiently the irradiation light from linear light source 125 be changed into the directional light of the depth of parallelism with regulation.

That is, if the maximum gauge L3 of cartridge 210b is the value that is less than 1mm, the quantity of cartridge 210b excessively becomes many, and the irradiation light sometimes hindering from linear light source 125 arrives coating layer (10,10 ').On the other hand, if the maximum gauge L3 of cartridge 210b, for surpassing the value of 100mm, reduces the unified overaction of the direct of travel of the irradiation light from linear light source 125, be sometimes difficult to change to the directional light with the depth of parallelism of regulation.

Therefore, the value in the scope that the maximum gauge L3 that more preferably makes cartridge 210b is 5～75mm, the more preferably value in the scope of 10～50mm.

Should illustrate, Figure 12 (a) is from film top 10(b with the aid of pictures) shown in the vertical view (planimetric map) of irradiation parallel light parts 200b.

In addition, Figure 12 (a) represents to see from film top that while irradiating parallel light parts 200b, the flat shape of the peristome of cartridge 210b is tetragonal situation (210b ').

On the other hand, Figure 12 (b)～(d) represents to see from film top while irradiating parallel light parts 200b, and the flat shape of the peristome of cartridge 210b is respectively hexagon, triangle and circular situation (210b ' ', 210b ' ' ', 210b ' ' ' ').

Should illustrate, the viewpoint not creating a difference on azimuth direction from the performance changing to directional light, the flat shape of the peristome of cartridge 210b preferably as Figure 12 (d) as shown in circle, but sometimes produce the problem of aperture opening ratio reduction.

Therefore the performance, most preferably changing to directional light is little and can increase the hexagon as shown in Figure 12 (b) of aperture opening ratio in the difference of azimuth direction.

In addition, the width L4 of the aggregate of a plurality of cartridge 210b is not particularly limited, but is conventionally preferably the value in the scope of 10～1000mm, the more preferably value in the scope of 50～500mm.

In addition, the thickness for the next door of the barrel of cartridge 210b, is also not particularly limited, and is conventionally preferably the value in the scope of 0.1～5mm, more preferably the value in the scope of 0.5～2mm.

And then the material substance for cartridge 210b, is also not particularly limited, for example, can use Aludip of having implemented heat-resisting black application etc.

In addition, regardless of the mode of irradiating parallel light parts, as shown in Figure 11 (b), the value in the scope that the upper end that all preferably makes to irradiate the irradiation parallel light parts in parallel light parts 200 is 10～1000mm to the length L 5 of lower end.

Its reason be due to, value in the scope that upper end by making above-mentioned irradiation parallel light parts is 10～1000mm to the length L 5 of lower end, thereby in the 2nd active energy ray irradiates, can further efficiently the irradiation light from linear light source 125 be changed into the directional light of the depth of parallelism with regulation.

; if above-mentioned length L 5 is for being less than the value of 10mm; the irradiation light from linear light source 125 easily directly sees through the inside of irradiating parallel light parts 200; the overaction that the direct of travel of the irradiation light from linear light source 125 is unified reduces, and is sometimes difficult to change to the directional light with the depth of parallelism of regulation.On the other hand, if above-mentioned length L 5 is for surpassing the value of 1000mm, linear light source 125 excessively becomes large with the distance of coating layer (10,10 '), is sometimes difficult to obtain sufficient illumination on the surface of coating layer (10,10 ').

Therefore, the value in the scope that the upper end that more preferably makes to irradiate parallel light parts is 20～750mm to the length L 5 of lower end, the more preferably value in the scope of 50～500mm.

Should illustrate, Figure 11 (b) is the axis direction 10(a with the aid of pictures from linear light source 125) shown in the outboard profile of irradiation parallel light parts 200a.

In addition, regardless of the mode of irradiating parallel light parts, as shown in Figure 11 (b), all preferably make to irradiate the value in the scope that the distance L 6 between parallel light parts 200 upper end and linear light source 125 lower end is 0～1000mm.

Its reason be due to, by making the value in scope that above-mentioned distance L 6 is 0～1000mm, thereby in the 2nd active energy ray irradiates, can further efficiently the irradiation light from linear light source 125 be changed into the directional light of the depth of parallelism with regulation.

That is, if above-mentioned distance L 6 is the value over 1000mm, the expansion of the irradiation light of the direction parallel with the axis direction of linear light source 125 excessively becomes large, even while being situated between by irradiation parallel light parts 200, is sometimes also difficult to obtain the directional light of regulation.

In addition, linear light source 125 excessively becomes large with the distance of coating layer (10,10 '), and the surface in coating layer (10,10 '), is difficult to obtain sufficient illumination sometimes.

On the other hand, if above-mentioned distance L 6 is excessive little value, plate-shaped member becomes taken in excess from the heat energy of linear light source, sometimes needs the deteriorated countermeasure of irradiation parallel light parts for preventing from being caused by thermal conductance.

Therefore, more preferably make to irradiate the value in the scope that the distance L 6 between parallel light parts 200 upper end and linear light source 125 lower end is 0.1～500mm, the more preferably value in the scope of 1～100mm.

In addition, regardless of the mode of irradiating parallel light parts, as shown in Figure 11 (b), all preferably make to irradiate the value in the scope that the distance L 7 between parallel light parts 200 lower end and the surface of coating layer (10,10 ') is 0～1000mm.

Its reason be due to, by making the value in scope that above-mentioned distance L 7 is 0～1000mm, thereby in the 2nd active energy ray irradiates, can to coating layer (10,10 '), irradiate more efficiently the directional light of the depth of parallelism with regulation.

That is,, if above-mentioned distance L 7 is the value that surpasses 1000mm, even unification is to the irradiation light of the depth of parallelism of regulation, sometimes at arrival coating layer (10,10 '), also can excessively expand before.

On the other hand, if above-mentioned distance L 7 is excessive little value, the slight vibration during sometimes due to irradiation causes irradiating the lower end of parallel light parts and the Surface Contact of coating layer.

Therefore, more preferably make to irradiate the value in the scope that the distance L 7 between parallel light parts 200 lower ends and the surface of coating layer (10,10 ') is 0.1～500mm, the more preferably value in the scope of 1～100mm.

In addition, irradiating parallel light parts is to instigate to irradiate the parts that light becomes directional light.Particularly, be to instigate to irradiate the parts that light becomes 10 ° of following directional lights of the depth of parallelism.

By making to irradiate the depth of parallelism of light, be the value in above-mentioned scope, thereby can efficient and stably form a plurality of columns, with respect to film thickness direction, using the rod structure region as the 2nd structural region that constant pitch angle stands in great numbers and form.

If the above-mentioned depth of parallelism, for surpassing the value of 10 °, cannot form rod structure region sometimes.

Therefore, irradiating the depth of parallelism that parallel light parts more preferably make to irradiate light is the parts of 5 ° of following values, and the depth of parallelism that more preferably makes to irradiate light is the parts of 2 ° of following values.

In addition, as irradiating light, can enumerate ultraviolet ray, electron beam etc., but the reason identical according to the reason with the 1st active energy ray irradiation process preferably used ultraviolet ray.

In addition, as ultraviolet irradiation condition, the peak illumination that preferably makes painting layer surface is 0.01～30mW/cm ²scope in value.

Its reason be due to, if peak illumination is for being less than 0.01mW/cm ²value, be sometimes difficult to form clearly rod structure region.On the other hand, if peak illumination is for surpassing 30mW/cm ²value, (A) composition and (B) composition before being separated, solidify, be sometimes difficult on the contrary form clearly rod structure region.

In addition, the irradiating angle of the translational speed of coating layer, irradiation light can be identical with the 1st active energy ray irradiation process.

In addition, in order to become the fully curing accumulative total light quantity of coating layer, also preferably irradiate differently with the 1st and the 2nd active energy ray, further irradiate active energy ray.

Owing to making the fully curing object of coating layer, so active energy ray is not now preferably directional light etc., but the random light of direct of travel.

In addition, the optical diffusion film after photocuring operation finally becomes spendable state by stripping technology sheet material.

7. optical diffusion film

(1) the 1st structural region

The optical diffusion film that utilizes manufacture method of the present invention and obtain is characterised in that, as for making incident light carry out the 1st structural region of anisotropic light diffusion, there are a plurality of plate like region that refractive index is different, that is the plate like region that, refractive index is relatively high (high index of refraction portion) low plate like region relative to refractive index (low-refraction portion) is in the shutter region that alternately configured in parallel forms of the either direction along face.

Below, the 1st structural region is specifically described.

(1)-1 refractive index

In the 1st structural region, preferably make the specific refractivity between plate like region that refractive index is different, that is, the specific refractivity of the refractive index of high index of refraction portion and low-refraction portion is more than 0.01 value.

Its reason be due to, by making above-mentioned specific refractivity, it is more than 0.01 value, thereby can make incident light stably reflection in the shutter region as the 1st structural region, more improve from the incident angle dependence of the 1st structural region and the opening angle of diffusion light.

More specifically, if above-mentioned specific refractivity is to be less than 0.01 value, incident light becomes narrow in the angle domain of shutter inner total reflection, and incident angle dependence excessively reduces or the opening angle of diffusion light excessively narrows down sometimes.

Therefore, more preferably making the specific refractivity between plate like region that refractive index in the 1st structural region is different is more than 0.05 value, more preferably more than 0.1 value.

Should illustrate, the specific refractivity of the refractive index of high index of refraction portion and low-refraction portion is more preferred more greatly, but from the selected viewpoint that can form the material in shutter region, thinks that 0.3 left and right is the upper limit.

In addition, in the 1st structural region, the value in the scope that the refractive index that preferably makes the plate like region that refractive index is relatively high (high index of refraction portion) is 1.5～1.7.

Its reason be due to, if the refractive index of high index of refraction portion is to be less than 1.5 value, too diminish with the difference of low-refraction portion, be sometimes difficult to obtain desirable shutter region.

On the other hand, if the refractive index of high index of refraction portion is for surpassing 1.7 value, optical diffusion film excessively reduces with the intermiscibility between the material substance in composition sometimes.

Therefore, the value in the scope that the refractive index that more preferably makes the high index of refraction portion in the 1st structural region is 1.52～1.65, the more preferably value in 1.55～1.6 scope.

Should illustrate, the refractive index of high index of refraction portion can be measured according to JIS K0062.

In addition, in the 1st structural region, the value in the scope that the refractive index that preferably makes the plate like region that refractive index is relatively low (low-refraction portion) is 1.4～1.5.

Its reason be due to, if the refractive index of above-mentioned low-refraction portion is to be less than 1.4 value, sometimes make the rigidity of resulting optical diffusion film reduce.

On the other hand, if the refractive index of above-mentioned low-refraction portion is for surpassing 1.5 value, become too small with the specific refractivity of high index of refraction portion, be sometimes difficult to obtain desirable shutter region.

Therefore, the value in the scope that the refractive index that more preferably makes the low-refraction portion in the 1st structural region is 1.42～1.48, the more preferably value in 1.44～1.46 scope.

Should illustrate, the refractive index in low-refraction portion for example can be measured according to JIS K0062.

(1)-2 width

In addition, as shown in Figure 13 (a)～(b), in the 1st structural region, preferably make the width (Sa, Sb) of high index of refraction portion 12 that refractive index is different and low-refraction portion 14 be respectively the value in the scope of 0.1～15 μ m.

Its reason be due to, by making the width of these plate like region, it is the value in the scope of 0.1～15 μ m, thereby can make incident light in the shutter region as the 1st structural region, more stably reflection, further improves from the incident angle dependence of the 1st structural region and the opening angle of diffusion light.

That is,, if the width of above-mentioned plate like region is the value that is less than 0.1 μ m,, regardless of the incident angle of incident light, be all sometimes difficult to display light diffusivity.On the other hand, if above-mentioned width is for surpassing the value of 15 μ m, the light of keeping straight in shutter region increases, and has the homogeneity variation of time diffusion.

Therefore,, in the 1st structural region, more preferably make the width of the plate like region that refractive index is different be respectively the value in the scope of 0.5～10 μ m, the more preferably value in the scope of 1～5 μ m.

Should illustrate, the width of the plate like region in formation shutter region, length etc. can be by utilizing optical digital microscopic examination to calculate.

(1)-3 thickness

In addition, as shown in Figure 13 (a)～(b), in the 1st structural region, preferably make thickness (length) La of high index of refraction portion 12 that refractive index is different and low-refraction portion 14 be respectively the value in the scope of 5～495 μ m.

Its reason be due to, if above-mentioned thickness is the value that is less than 5 μ m, the thickness in shutter region is not enough, the incident light of keeping straight in shutter region increases, and is sometimes difficult to obtain the opening angle of sufficient incident angle dependence and diffusion light.

On the other hand, if above-mentioned thickness is for surpassing the value of 495 μ m, while optical diffusion film being formed to shutter region with composition irradiation active energy ray, due to the shutter region of initial stage formation, photopolymerisable direct of travel spreads, and is sometimes difficult to form desirable shutter region.

Therefore,, in the 1st structural region, more preferably make the thickness of the plate like region that above-mentioned refractive index is different be respectively the value in the scope of 40～310 μ m, the more preferably value in the scope of 95～255 μ m.

Should illustrate, as shown in Figure 13 (b), shutter region also can not be formed to the upper and lower side part on film thickness direction in the 1st structural region.

; although the width Lb that does not form the upper and lower side part in shutter region also depends on the thickness of the 1st structural region; but be conventionally preferably the value in the scope of 0～100 μ m, more preferably the value in the scope of 0～50 μ m, the more preferably value in the scope of 0～5 μ m.

(1)-4 pitch angle

In addition, as shown in Figure 13 (a)～(b), in the 1st structural region, the high index of refraction portion 12 that preferred index is different and low-refraction portion 14 extend with constant tiltangleθ a with respect to film thickness direction.

Its reason be due to, by making the pitch angle of plate like region constant, in the shutter region as the 1st structural region, can make incident light more stably reflect, further improve from the incident angle dependence of the 1st structural region and the opening angle of diffusion light.

In addition, as shown in Figure 13 (c), also preferred shutter region is crooked.

Its reason be due to, by making shutter region crooked, thereby can reduce the incident light of keeping straight in shutter region, improve the homogeneity of light diffusion.

Should illustrate, when crooked shutter region like this can be irradiated by the 1st active energy ray of recording in carrying out the 2nd embodiment, while the irradiating angle that changes irradiation light, irradiate light and obtain, still also depend on to a great extent the kind of the material substance that forms shutter region.

In addition, θ a refers to that the face of the shutter regions perpendicular of extending in the either direction along with respect to along along face cuts off Shi cross section by film, the pitch angle of the plate like region when angle by with respect to film normal to a surface of measuring is made as 0 ° (°).

More specifically, as shown in figure 13, refer to that incident light irradiates the angle of narrow side in the normal of face of side and plate like region angulation.Should illustrate, as shown in Figure 13 (a), the window shutter of take tilts Shi pitch angle to the right as benchmark, and the window shutter Shi pitch angle that tilts is to the left labeled as negative.

(2) the 2nd structural regions

Optical diffusion film of the present invention is characterised in that, as the 2nd structural region for making incident light carry out the diffusion of isotropy light, to have the rod structure region that the relatively much higher column of the refractive index of making stands in great numbers and forms in the relative Di of refractive index region.

Below, the 2nd structural region is specifically described.

(2)-1 refractive index

In the 2nd structural region, preferably making the refractive index of column and the specific refractivity in refractive index compare Di region is more than 0.01 value.

Its reason be due to, by making above-mentioned specific refractivity, it is more than 0.01 value, thereby can make incident light in the rod structure region as the 2nd structural region, stably reflection, further improves from the incident angle dependence of the 2nd structural region and the opening angle of diffusion light.

That is, if above-mentioned specific refractivity is to be less than 0.01 value, incident light becomes narrow in the angle domain of rod structure region inner total reflection, and incident angle dependence excessively reduces sometimes, or the opening angle of diffusion light excessively narrows down.

Therefore, more preferably making the refractive index of column and the specific refractivity of dielectric object in the 2nd structural region is more than 0.05 value, more preferably more than 0.1 value.

Should illustrate, specific refractivity is more preferred more greatly, but from the selected viewpoint that can form the material in rod structure region, thinks that 0.3 left and right is the upper limit.

(2)-2 maximum gauges

In addition, as shown in Figure 14 (a), in the 2nd structural region, the maximum gauge Sc that preferably makes the cross section of column is the value in the scope of 0.1～15 μ m.

Its reason be due to, by making above-mentioned maximum gauge, it is the value in the scope of 0.1～15 μ m, thereby can make incident light in the rod structure region as the 2nd structural region, more stably reflection, further improves from the incident angle dependence of the 2nd structural region and the opening angle of diffusion light.

That is,, if above-mentioned maximum gauge is the value that is less than 0.1 μ m,, regardless of the incident angle of incident light, be all sometimes difficult to display light diffusivity.On the other hand, if above-mentioned maximum gauge is for surpassing the value of 15 μ m, the light of keeping straight in rod structure region increases, and has the homogeneity variation of time diffusion.

Therefore,, in the 2nd structural region, the maximum gauge that more preferably makes the cross section of column is the value in the scope of 0.5～10 μ m, the more preferably value in the scope of 1～5 μ m.

Should illustrate, the cross sectional shape of column is not particularly limited, but such as being preferably circle, ellipse, polygon, abnormity etc.

In addition, the cross section of column refers to along the face parallel with film surface and cuts off the cross section forming.

Should illustrate, the maximum gauge of column, length etc. can be by observing to calculate with optics digital microscope.

(2)-3 thickness

In addition, in the 2nd structural region, thickness (length) Lc that preferably makes column is the value in the scope of 5～495 μ m.

Its reason be due to, if above-mentioned thickness is the value that is less than 5 μ m, the thickness of column is not enough, the incident light of keeping straight in rod structure region increases, and is sometimes difficult to obtain the opening angle of sufficient incident angle dependence and diffusion light.

On the other hand, if above-mentioned thickness is for surpassing the value of 495 μ m, while optical diffusion film being formed to rod structure region with composition irradiation active energy ray, due to the rod structure region of initial stage formation, photopolymerisable direct of travel spreads, and is sometimes difficult to form desirable rod structure region.

Therefore,, in the 2nd structural region, the thickness that more preferably makes column is the value in the scope of 40～310 μ m, the more preferably value in the scope of 95～255 μ m.

Should illustrate, as shown in Figure 14 (c), rod structure region can not be formed to the upper and lower side part on film thickness direction in the 2nd structural region.

That is,, although do not form the thickness that the width Ld of the upper and lower side part in rod structure region also depends on the 2nd structural region, be conventionally preferably the value in the scope of 0～50 μ m, more preferably the value in the scope of 0～5 μ m.

(2) distance between-4 columns

In addition, as shown in Figure 14 (a), in the 2nd structural region, preferably make the distance between column, that is, the space P between the column of adjacency is the value in the scope of 0.1～15 μ m.

Its reason be due to, by making above-mentioned distance, it is the value in the scope of 0.1～15 μ m, thereby can make incident light in the rod structure region as the 2nd structural region, more stably reflection, further improves from the incident angle dependence of the 2nd structural region and the opening angle of diffusion light.

That is,, if above-mentioned distance is the value that is less than 0.1 μ m,, regardless of the incident angle of incident light, be all sometimes also difficult to display light diffusivity.On the other hand, if above-mentioned distance is for surpassing the value of 15 μ m, the light of keeping straight in rod structure increases, and has the homogeneity variation of time diffusion.

Therefore,, in the 2nd structural region, more preferably making distance between column is the value in the scope of 0.5～10 μ m, the more preferably value in the scope of 1～5 μ m.

(2)-5 pitch angle

In addition, as shown in Figure 14 (b)～(c), in the 2nd structural region, column 22 preferably stands in great numbers with constant tiltangleθ b with respect to film thickness direction.

Its reason be due to, by making the pitch angle of column constant, thereby in the rod structure region as the 2nd structural region, can make incident light more stably reflect, further improve from the incident angle dependence of the 2nd structural region and the opening angle of diffusion light.

In addition, as shown in Figure 14 (d), also preferably column is crooked.

Its reason be due to, by making column crooked, thereby can reduce the incident light of keeping straight in rod structure region, further improve the homogeneity of light diffusion.

Should illustrate, when crooked column like this can irradiate by the 2nd active energy ray of recording in carrying out the 2nd embodiment, while changing the irradiating angle that irradiates light, irradiate light and obtain, but also depending on to a great extent the kind of the material substance that forms rod structure region.

In addition, θ b refers to vertical with face and 1 column integral body is cut into the face of 2 along axis film is cut off to Shi cross section, the pitch angle of the column when angle by with respect to film normal to a surface of measuring is made as 0 ° (°) (angle of a narrow side in this normal and column angulation).Should illustrate, the post as shown in Figure 14 (b) of take tilts Shi pitch angle to the right as benchmark, and the post Shi pitch angle that tilts is to the left labeled as negative.

(3) total film thickness

In addition, preferably making the total film thickness of optical diffusion film of the present invention is the value in the scope of 50～500 μ m.

Its reason be due to, if the total film thickness of optical diffusion film is the value that is less than 50 μ m, the light of keeping straight in rod structure region and shutter region increases, and is sometimes difficult to display light diffusivity.On the other hand, if the total film thickness of optical diffusion film is for surpassing the value of 500 μ m, while optical diffusion film being formed to rod structure region and shutter region with composition irradiation active energy ray, the rod structure region forming due to the initial stage and shutter region and photopolymerisable direct of travel spreads, be difficult to form desirable rod structure region and shutter region sometimes.

Therefore, the total film thickness that more preferably makes optical diffusion film is the value in the scope of 80～350 μ m, the more preferably value in the scope of 100～260 μ m.

Should illustrate, the 1st structural region and the 2nd structural region, along the film thickness direction of optical diffusion film, arrange successively on above-below direction, for its order, quantity, are not particularly limited.

(4) combination at angle of inclination

In addition, if optical diffusion film of the present invention, by regulate respectively tilt angle theta a with respect to the plate like region of the film thickness direction in the 1st structural region, with the tilt angle theta b of column with respect to the film thickness direction in the 2nd structural region, thereby can change its light diffusion property.

For example, by the incident angle dependence that each structural region has is repeated, thereby not only can suppress the fluctuation of light diffusion property, obtain good incident angle dependence, can also effectively expand the opening angle of diffusion light.

Now, in the 1st structural region, preferably make the value in scope that the tilt angle theta a with respect to the plate like region of film thickness direction is-80～80 °, and in the 2nd structural region, preferably make the value in scope that the tilt angle theta b with respect to the column of film thickness direction is-80～80 °, and the absolute value that preferably makes θ a-θ b is the value in the scope of 0～80 °, the absolute value that more preferably makes θ a-θ b is the value in the scope of 5～20 °.

Should illustrate, θ a herein and the content of θ b are as mentioned above.

In addition, by the incident angle dependence that each structural region is had, stagger, thus can be effectively and easily expand light diffusion incident angle region.

Now, in the 1st structural region, preferably make the value in scope that the tilt angle theta a with respect to the plate like region of film thickness direction is-80～80 °, and in the 2nd structural region, preferably make the value in scope that the tilt angle theta b with respect to the column of film thickness direction is-80～80 °, and the absolute value that preferably makes θ a-θ b is the value in the scope of 5～60 °, the absolute value that more preferably makes θ a-θ b is the value in the scope of 20～45 °.

(5) purposes

In addition, as shown in figure 15, preferably by the optical diffusion film that utilizes manufacture method of the present invention and obtain for reflection-type liquid-crystal display device 100.

Its reason be due to, the optical diffusion film obtaining if utilize manufacture method of the present invention, can and make its transmission and take in the inside of liquid crystal indicator efficiently by exterior light optically focused, and, in order can, using this light as light source utilization, to spread efficiently.

Therefore, optical diffusion film preferred disposition of the present invention in the upper surface of the liquid crystal cells 110 being formed by glass plate (104,108), liquid crystal 106 and mirror reflective plate 107 etc. or below, and use as the light diffusing sheet 103 in reflection-type liquid-crystal display device 100.

Should illustrate, with regard to optical diffusion film of the present invention, by being provided in polaroid 101, polarizer 102, thereby can also obtain wide visual field angle polaroid ,Kuan visual field polarizer.

Embodiment

Below, with reference to embodiment, further describe the manufacture method of optical diffusion film of the present invention.

［ embodiment 1 ］

1.(B) composition is synthetic

In container, accommodate as 1 mole of the polypropylene glycol (PPG) of the weight-average molecular weight 9200 of (B2) composition, with respect to this, accommodate as 2 moles of the isophorone diisocyanate (IPDI) of (B1) composition with as after 2 moles of the 2-hydroxyethyl methacrylates (HEMA) of (B3) composition, carry out according to conventional methods polymerization, obtain the polyethers urethane methacrylate of weight-average molecular weight 9900.

Should illustrate, the weight-average molecular weight of polypropylene glycol and polyethers urethane methacrylate is the polystyrene conversion value determining according to following condition with gel permeation chromatography (GPC).

GPC determinator: TOSOH Co., Ltd. system, HLC-8020

GPC column:TOSOH Co., Ltd. system (following, by recording by order)

TSK?guard?column?HXL-H

TSK?gel?GMHXL（×2）

TSK?gel?G2000HXL

Measure solvent: tetrahydrofuran

Measure temperature: 40 ℃

2. the preparation of composition for optical diffusion film

Then, polyethers urethane methacrylate 100 weight portions with respect to the weight-average molecular weight 9900 of resulting conduct (B) composition, add the adjacent phenyl phenoxy group of acrylic acid ethoxy ethyl ester (the Xin Zhong village KCC system as the weight-average molecular weight 268 being represented by following formula (3) of (A) composition, NK ESTER A-LEN-10) after 100 weight portions and conduct 2-hydroxy-2-methyl propiophenone 10 weight portions of (C) composition, under the condition of 80 ℃, heat mixing, obtain optical diffusion film composition.Should illustrate, (A) composition and (B) refractive index of composition be to utilize Abbe refractometer (ATAGO company system, the name of an article " Abbe refractometer DR-M2 ", Na light source, wavelength 589nm) to measure according to JIS K0062, result is respectively 1.58 and 1.46.

3. the coating of composition for optical diffusion film

Then, for the transparent polyethylene terephthalate film of the sheet as technique sheet material (following, to be called PET), the anisotropic light-diffusing film composition that coating obtains, the coating layer of formation thickness 200 μ m.

4. the photocuring of coating layer

(1) the 1st ultraviolet ray is irradiated

Then, prepare cold mirror that in the high-pressure sodium lamp in wire (diameter 25mm) as Fig. 9 (a) as shown in, subsidiary optically focused is used and must ultraviolet lamp (EYE GRAPHICS Co., Ltd. system, ECS-4011GX).

Then, on heat radiation cut-off filter frame, shadow shield is set, the illuminated surperficial ultraviolet ray in coating layer is set as: when the normal direction of the duplexer consisting of coating layer and PET when the long side direction of the UV-lamp from wire is seen is made as 0 °, from the ultraviolet irradiation angle (θ 3 of Fig. 9 (b)) of lamp direct projection, become-35 °.

Now, be set as: the height of the lamp from coating layer becomes 500mm, peak illumination becomes 1.7mW/cm ².

In addition, in order to prevent that the reflected light of shadow shield etc. from becoming parasitic light and the photocuring of coating layer is exerted an influence in irradiation unit inside, shadow shield is also set near conveyor, coating layer is only irradiated to the ultraviolet mode of directly sending from lamp, sets.

Then, Yi Bian utilize conveyor to make coating layer, to the right in Fig. 9 (a), the speed with 0.2m/ minute moves, Yi Bian irradiation ultraviolet radiation.

(2) the 2nd ultraviolet rays are irradiated

Then,, after the 1st ultraviolet irradiation process, (Lintec Co., Ltd. system, SP-PET382050) lamination coating layer exposes face side to utilize the stripping film with ultraviolet (uv) transmission of thickness 38 μ m.

Then, prepare the cold mirror used with optically focused in the high-pressure sodium lamp in wire (diameter 25mm) as Fig. 9 (a) as shown in and must ultraviolet lamp (EYE GRAPHICS Co., Ltd. system, ECS-4011GX).

Then, between the UV-lamp and coating layer of wire, configuration a plurality of plate-shaped members irradiation parallel light parts that configured in parallel forms respectively as shown in Figure 10 (a) shows.

Now, while seeing from film top, in the direction of the axis direction quadrature of the UV-lamp of plate-shaped member and wire, that is, and the direction configuration irradiation parallel light parts of the θ 4=90 in Figure 11 (a) °.

Then, Jie by irradiating parallel light parts from the UV-lamp irradiation ultraviolet radiation of wire, thereby to make the depth of parallelism be 2 ° of following directional lights almost becomes the mode of 0 ° with illumination angle (θ 3 of Fig. 9 (b)) and is irradiated to coating layer across stripping film, its result, obtains the optical diffusion film of total film thickness 195 μ m.

Peak illumination is now made as to 1.84mW/cm ², the lamp height translational speed that is made as 500mm, coating layer is made as 1m/ minute.

Should illustrate, the thickness of optical diffusion film can be used level pressure thickness tester (precious Co., Ltd. of institute system, the TECLOCK PG-02J of making) to measure.

In addition, the interval (L1 in Figure 11 (a)) of irradiating a plurality of plate-shaped members in parallel light parts is 20mm, the width of plate-shaped member (L2 in Figure 11 (a)) is 300mm, and the thickness of plate-shaped member is 1mm, and material is the aluminum steel of having implemented heat-resisting black application.

And then, the upper end of irradiation parallel light parts is 200mm to the length (L5 in Figure 11 (b)) of lower end, the distance (L6 in Figure 11 (b)) of irradiating between the upper end of parallel light parts and the lower end of the UV-lamp of wire is 200mm, and lower end and the distance between the surface of coating layer (L7 in Figure 11 (b)) of irradiating parallel light parts are 100mm.

In addition, confirmed that the optical diffusion film obtaining is the optical diffusion film that the pitch angle of shutter is-10 ° for-23 °, the pitch angle of column.

Should illustrate, Figure 16 represents to cut off along the vertical face of the plate like region with shutter the schematic diagram in Shi Mo cross section.

In addition, the thickness of the 1st structural region is 120 μ m, and the thickness of the 2nd structural region is 75 μ m.

And then, the cross-section photograph of the optical diffusion film obtaining is shown in to Figure 17 (a)～(b).Figure 17 (a) is cross-section photograph when film is cut off along the face vertical with plate like region in shutter, and Figure 17 (b) is cross-section photograph when film is cut off along the face vertical with respect to the section in Figure 17 (a).

In addition, from Figure 17 (a) and (b), even if replace the high ultraviolet pointolite of the depth of parallelism shown in reference example as described later, use wire high-pressure sodium lamp and a plurality of plate-shaped member irradiation parallel light parts that configured in parallel forms respectively, also similarly can obtain the stepped construction in shutter region and rod structure region with reference example.

Should illustrate, although do not show data, in reference example 1, as described later, in embodiment 1, also use angle colour meter (Suga Test Instruments Co., Ltd.VC-2) to measure the light diffusion property of optical diffusion film.

Its results verification, although when incidence angle θ 1=-20 ° of left and right of incident light, be difficult to produce the diffusion of light, but during the scope of incidence angle θ 1=-10～0 °, the diffusion of the isotropy light of generation based on rod structure region, during scope in incidence angle θ 1=-60～-30 °, produces the anisotropic light diffusion based on shutter region, by the light diffusion incident angle dependence based on 2 structural regions is staggered, thereby can effectively expand light diffusion incident angle region.

［ embodiment 2 ］

In embodiment 2, to irradiate parallel light parts and change into the irradiation parallel light parts of the aggregate as a plurality of cartridges as shown in Figure 10 (b), and the translational speed of coating layer is changed into 0.5m/ minute, and the peak illumination that makes painting layer surface is 1.22mW/cm ², in addition, similarly to Example 1, the pitch angle that obtains shutter for-23 °, the pitch angle of column be the optical diffusion film of 3 °.

Should illustrate, Figure 18 represents to cut off along the vertical face of the plate like region with shutter the schematic diagram in Shi Mo cross section.

Now, the flat shape of irradiating the peristome of the cartridge in parallel light parts is hexagon, the maximum gauge of cartridge (L3 ' ' in Figure 12 (b)) is 10mm, the width of the aggregate of a plurality of cartridges (L4 in Figure 12 (a)) is 30mm, the thickness in the next door of the barrel in cartridge is 0.2mm, and material is the aluminum steel of having implemented heat-resisting black application.

And then, the cross-section photograph of the optical diffusion film obtaining is shown in to Figure 19 (a)～(b).Figure 19 (a) is cross-section photograph when film is cut off along the face vertical with plate like region in shutter, cross-section photograph when Figure 19 (b) makes along the face vertical with respect to the section in Figure 19 (a), film to be cut off.

In addition, from Figure 19 (a) and (b), even if replace the high ultraviolet pointolite of the depth of parallelism shown in reference example as described later, during the pseudo-source of parallel light of what is called that use consists of high-pressure sodium lamp and a plurality of cartridge irradiation parallel light parts that set configuration forms respectively of wire, also similarly can obtain the stepped construction in shutter region and rod structure region with reference example.

Should illustrate, although data are not shown, in reference example 1, as described later, in embodiment 2, also use angle colour meter to measure the light diffusion property of optical diffusion film.

Its results verification, although when incidence angle θ 1=-20 ° of left and right of incident light, be difficult to produce the diffusion of light, but during the scope in incidence angle θ 1=-10～0 °, the diffusion of the isotropy light of generation based on rod structure region, during scope in incidence angle θ 1=-60～-30 °, produces the anisotropic light diffusion based on shutter region, by the light diffusion incident angle dependence based on 2 structural regions is staggered, thereby can effectively expand light diffusion incident angle region.

［ reference example 1 ］

1. the manufacture of optical diffusion film

In reference example 1, the θ 3 that the 1st ultraviolet ray is irradiated changes into-40 °, and implements the 2nd ultraviolet ray irradiation by following mode, in addition, obtains similarly to Example 1 optical diffusion film.

; use and pass through in ultraviolet pointolite (DENSO Corporation system under mountain; HYPERCURE200) in, the uniform exposure adapter of OPTION being installed and being made the depth of parallelism is 2 ° of following devices; the mode that becomes 40 ° with the incident angle (θ 3 of Fig. 9) of directional light is irradiated across stripping film, thereby obtains the optical diffusion film of total film thickness 195 μ m.

Peak illumination is now made as to 5mW/cm ², the lamp height translational speed that is made as 800mm, coating layer is made as 0.5m/ minute.

In addition, confirmed the optical diffusion film obtaining be shutter pitch angle for-27 °, the pitch angle of column be the optical diffusion film of 27 °.

Should illustrate, Figure 20 (a) represents to cut off along the vertical face of the plate like region with shutter the schematic diagram in Shi Mo cross section.

And then, the cross-section photograph of the optical diffusion film obtaining is shown in to Figure 21 (a)～(b).Figure 21 (a) is cross-section photograph when film is cut off along the face vertical with plate like region in shutter, and Figure 21 (b) is cross-section photograph when film is cut off along the face vertical with respect to the section in Figure 21 (a).

2. measure

Use angle colour meter, as shown in Figure 20 (a), from the top of the optical diffusion film that obtains, to this film with incidence angle θ 1=60 ° incident light (illuminant-C, 2 ° of field angle).

Then, measure expansion and brightness (%) distribution thereof of the diffusion light being spread by optical diffusion film.The value that said determination be the results are shown in to the longitudinal axis of the scatter diagram shown in Figure 20 (c) is on the transverse axis of 0 °.

That is, the expansion angle of the value representation diffusion light of transverse axis (°) scope, the color of plotting represents to diffuse to the brightness (%) of the diffusion light of this angle.

Herein, with regard to the color of plotting and the relation of brightness (%), the color of plotting approaches redness, represents that brightness more approaches 100%, and the color of plotting approaches green, represents that brightness more approaches 50%, and the color of plotting more approaches mazarine, represents that brightness more approaches 0%.Should illustrate, details is as shown in Figure 20 (b).

In addition, in order further the distribution of the expansion of the diffusion light on the Width of incident light and its brightness (%) also to be measured, on one side using the regulation on the face of optical diffusion film a bit as center, optical diffusion film scope with-80～80 ° in same level is rotated, Yi Bian carry out identical mensuration.

Should illustrate, the angle of above-mentioned rotation is the angle of the rotation of the angle of the optical diffusion film while instigating said determination while being 0 °.The value that for example, measurement result while, making 20 ° of optical diffusion film rotations is indicated on the longitudinal axis of the scatter diagram shown in Figure 20 (c) is on the transverse axis of 20 °.

Therefore,, for the scatter diagram shown in Figure 20 (c), for example, brightness is that the photodistributed region of more than 30% diffusion is the region of the dotted line in Figure 20 (c).

Then, as shown in Figure 20 (d)～(k), incidence angle θ to optical diffusion film 1 is changed into respectively to 50 °, 40 °, 30 °, 0 ° ,-30 ° ,-40 ° ,-50 ° ,-60 °, during with incidence angle θ 1=60 °, similarly measure the expansion of diffusion light and the distribution of its brightness (%).

3. result

As shown in Figure 20 (c)～(k), for the optical diffusion film of reference example 1, although when the scope of the incidence angle θ 1=0 ° left and right of incident light, the diffusion that is difficult to produce light, but during the scope in incidence angle θ 1=30～60 °, produce the isotropy light diffusion based on rod structure region.

In addition, during scope in incidence angle θ 1=-60～-30 °, produce the anisotropic light diffusion based on shutter region.

Therefore, known by the light diffusion incident angle dependence based on 2 structural regions is staggered, thus can effectively expand light diffusion incident angle region.

［ reference example 2 ］

In reference example 2, when coating layer is solidified, the θ 3 that the 1st ultraviolet ray is irradiated changes to 40 °, in addition, with reference example 1 similarly, the pitch angle that obtains shutter is that 27 °, the pitch angle of column are the optical diffusion film of 27 °.

Should illustrate, Figure 22 represents to cut off along the vertical face of the plate like region with shutter the schematic diagram in Shi Mo cross section.

In addition, make the incidence angle θ 1 of optical diffusion film be respectively 25 °, 35 °, 45 °, 55 °, in addition, similarly the distribution of the expansion of diffusion light and its brightness (%) is measured with reference example 1.

Its result, in the optical diffusion film of reference example 2, light in shutter region and rod structure region diffusion incident angle dependence is almost overlapping, and light diffusion incident angle region is the so narrow scope of scope of incidence angle θ 1=25～55 °.

Yet the optical diffusion film of having confirmed reference example 2 and comparative example 1 described later are compared diffusion uniformity of light with 2 high, the expansion of diffusion light of Width of comparing incident light with comparative example 3 with 4 is large.

［ reference example 3 ］

In reference example 3, the θ 3 that the 1st ultraviolet ray is irradiated changes to 40 °, and the incident angle of the directional light that the 2nd ultraviolet ray is irradiated changes to 0 °, in addition, with reference example 1 similarly, the pitch angle that obtains shutter is that 27 °, the pitch angle of column are the optical diffusion film of 0 °.

Should illustrate, Figure 23 (a) represents to cut off along the vertical face of the plate like region with shutter the schematic diagram in Shi Mo cross section.

In addition, as shown in Figure 23 (b)～(h), make to be respectively 0 °, 10 °, 20 °, 30 °, 40 °, 50 °, 60 ° with respect to the incidence angle θ 1 of optical diffusion film, in addition, with reference example 1 similarly, the distribution of the expansion of diffusion light and its brightness (%) is measured.

Its result is known, as shown in Figure 23 (b)～(h), for the optical diffusion film of reference example 3, although when incidence angle θ 1=20 ° of left and right of incident light, be difficult to produce the diffusion of light, but during the scope in incidence angle θ 1=0～10 °, the isotropy light diffusion of generation based on rod structure region, during scope in incidence angle θ 1=30～60 °, the anisotropic light diffusion of generation based on shutter region, by the light diffusion incident angle dependence based on 2 structural regions is staggered, thereby can effectively expand light diffusion incident angle region.

［ reference example 4 ］

In reference example 4, the θ 3 that the 1st ultraviolet ray is irradiated changes to 40 °, and the incident angle of the directional light that the 2nd ultraviolet ray is irradiated changes to 20 °, in addition, with reference example 1 similarly, the pitch angle that obtains shutter is that 27 °, the pitch angle of column are the optical diffusion film of 14 °.

Should illustrate, Figure 24 (a) represents to cut off along the vertical face of the plate like region with shutter the schematic diagram in Shi Mo cross section.

In addition, as shown in Figure 24 (b)～(g), make the incidence angle θ 1 of optical diffusion film be respectively 5 °, 15 °, 25 °, 35 °, 45 °, 55 °, in addition, similarly the distribution of the expansion of diffusion light and its brightness (%) is measured with reference example 1.

Its result, as shown in Figure 24 (b)～(g), in the optical diffusion film of reference example 4, during scope in incidence angle θ 1=5～25 of incident light °, the isotropy light diffusion of generation based on rod structure region, during scope in incidence angle θ 1=25～55 °, the anisotropic light diffusion of generation based on shutter region, although by the light diffusion incident angle dependence based on 2 structural regions is staggered, but a part is repeated, thereby can effectively expand light diffusion incident angle region.

［ comparative example 1 ］

In comparative example 1, the 1st ultraviolet ray that is not used to form shutter region is irradiated, and the incident angle of the directional light that the 2nd ultraviolet ray that is used to form rod structure region is irradiated changes to 0 °, in addition, with reference example 1 similarly, obtain only thering is on the whole in the region that is equivalent to the 1st structural region and the 2nd structural region the optical diffusion film that pitch angle is the rod structure of 0 °.

Should illustrate, Figure 25 (a) represents to cut off along the vertical face of the plate like region with shutter the schematic diagram in Shi Mo cross section.

In addition, as shown in Figure 25 (b)～(j), make the incidence angle θ 1 of optical diffusion film be respectively 20 °, 15 °, 10 °, 5 °, 0 ° ,-5 ° ,-10 ° ,-15 ° ,-20 °, in addition, with reference example 1 similarly, the distribution of the expansion of diffusion light and its brightness (%) is measured.

Its result, as shown in Figure 25 (b)～(j), in the optical diffusion film of comparative example 1, only has rod structure, so light diffusion incident angle region is the so narrow scope of scope of θ 1=-15～15 °.

In addition, the central part of known diffusion light is high especially with other parts phase specific luminance, and diffusion uniformity of light is low.

［ comparative example 2 ］

In comparative example 2, the 1st ultraviolet ray that is not used to form shutter region is irradiated, and the incident angle that is used in the directional light of the 2nd ultraviolet ray irradiation that forms rod structure region changes to 40 °, in addition, with reference example 1 similarly, obtain only thering is on the whole in the region that is equivalent to the 1st structural region and the 2nd structural region the optical diffusion film that pitch angle is the rod structure of 27 °.

Should illustrate, Figure 26 (a) represents to cut off along the vertical face of the plate like region with shutter the schematic diagram in Shi Mo cross section.

In addition, as shown in Figure 26 (b)～(k), make the incidence angle θ 1 of optical diffusion film be respectively 15 °, 20 °, 25 °, 30 °, 35 °, 40 °, 45 °, 50 °, 55 °, 60 °, in addition, with reference example 1 similarly, the distribution of the expansion of diffusion light and its brightness (%) is measured.

Its result, as shown in Figure 26 (b)～(k), the optical diffusion film of comparative example 2 only has rod structure, so light diffusion incident angle region is the so narrow scope of scope of θ 1=25～60 °.

［ comparative example 3 ］

In comparative example 3, the θ 3 that the 1st ultraviolet ray is irradiated changes to 0 °, as the 2nd ultraviolet ray, irradiates, and irradiates peak illumination 13.7mW/cm ², accumulative total light quantity 213.6mJ/cm ²scattered light, in addition, with reference example 1 similarly, obtain having pitch angle as the 1st structural region and be the optical diffusion film that the shutter region of 0 ° and its top do not form the region of shutter.

Should illustrate, Figure 27 (a) represents to cut off along the vertical face of the plate like region with shutter the schematic diagram in Shi Mo cross section.

In addition, as shown in Figure 27 (b)～(h), make the incidence angle θ 1 of optical diffusion film be respectively 20 °, 15 °, 10 °, 5 °, 0 ° ,-5 ° ,-10 °, in addition, with reference example 1 similarly, the distribution of the expansion of diffusion light and its brightness (%) is measured.

Its result, as shown in Figure 27 (b)～(h), the optical diffusion film of comparative example 3 only has shutter, so light diffusion angular regions is the so narrow scope of scope of θ 1=-5～15.

In addition, the anisotropy of known diffusion light is large, and the expansion of the diffusion light on the Width of incident light is little.

［ comparative example 4 ］

In comparative example 4, the θ 3 that the 1st ultraviolet ray is irradiated changes to 40 °, as the 2nd ultraviolet ray, irradiates, and irradiates peak illumination 13.7mW/cm ², accumulative total light quantity 213.6mJ/cm ²scattered light, in addition, with reference example 1 similarly, obtain having pitch angle as the 1st structural region and be the optical diffusion film that the shutter region of 27 ° and its top do not form the region of shutter.

Should illustrate, Figure 28 (a) represents to cut off along the vertical face of the plate like region with shutter the schematic diagram in Shi Mo cross section.

In addition, as shown in Figure 28 (b)～(i), make the incidence angle θ 1 of optical diffusion film be respectively 25 °, 30 °, 35 °, 40 °, 45 °, 50 °, 55 °, 60 °, in addition, similarly manufacture optical diffusion film with reference example 1.

In addition, as shown in Figure 28 (b)～(i), the optical diffusion film of comparative example 4 only has shutter, so light diffusion angular regions is θ 1=30～60 ° so narrow scopes.

Utilizability in industry

As detailed above, according to the present invention, by the shutter region that is provided for making incident light carry out anisotropic light diffusion with for making incident light carry out the rod structure region of isotropy light diffusion, thereby can access, there is the wide optical diffusion film of good incident angle dependence and light diffusion incident angle region in film.

And then, by being used to form successively that the 1st active energy ray in shutter region irradiates and Jie of being used to form rod structure region is irradiated by irradiating the 2nd active energy ray that parallel light parts carry out, thereby can utilize linear light source easily to obtain having the optical diffusion film of above-mentioned characteristic.

Therefore, for the optical diffusion film obtaining with regard to utilizing manufacture method of the present invention, light control film in reflective liquid crystal device, field angle controlling diaphragm, field angle expansion film and screen for projection be can also offer, their high-qualityization and the raising of manufacturing efficiency are expected to contribute to significantly.

Symbol description

1: coating layer, 2: technique sheet material, 10: the 1 structural regions (anisotropic light-diffusing film), 12: the plate like region that refractive index is relatively high (high index of refraction part), 13: shutter, 13 ': the boundary surface of shutter, 14: the plate like region that refractive index is relatively low (low-refraction part), 20: the 2 structural regions (isotropy optical diffusion film), 22: column, 24: the part (low-refraction part) beyond column, 30: optical diffusion film, 50: active energy ray (directly light), 60: active energy ray (directional light), 120: ultraviolet lamp, 121: heat radiation cut-off filter, 122: cold mirror, 123: shadow shield, 125: the UV-lamp of wire (linear light source), 100: reflection-type liquid-crystal display device, 101: polaroid, 102: polarizer, 103: light diffusing sheet, 104: glass plate, 105: color filter, 106: liquid crystal, 107: mirror reflective plate, 108: glass plate, 110: liquid crystal cells, 200: irradiate parallel light parts, 210: light-blocking member, 210a: plate-shaped member, 210b: cartridge

Claims

1. a manufacture method for optical diffusion film, is characterized in that, is to have for making incident light carry out the 1st structural region of anisotropic light diffusion and for making incident light carry out the manufacture method of optical diffusion film of the 2nd structural region of isotropy light diffusion;

The manufacture method of described optical diffusion film comprises following operation (a)～(d):

(a) prepare the operation of composition for optical diffusion film,

(b) technique sheet material is coated with to described optical diffusion film composition, forms the operation of coating layer,

(c) to described coating layer, carrying out the 1st active energy ray irradiates, a plurality of plate like region that refractive index is different that make that part forms as the 1st structural region below described coating layer alternately configure the shutter region forming in the either direction along face, and the residual operation that does not form the region of shutter of upper section at described coating layer

(d) to described coating layer, further carrying out the 2nd active energy ray irradiates, in the described region that does not form shutter, form the rod structure region that makes the relatively much higher column of refractive index stand in great numbers and form as the 2nd structural region in the relative Di of refractive index region

Wherein, as described the 2nd active energy ray, irradiate, described coating layer is situated between and irradiates the operation from the irradiation light of linear light source by irradiating parallel light parts.

2. the manufacture method of optical diffusion film according to claim 1, is characterized in that, described irradiation parallel light parts consist of a plurality of plate-shaped members, and while seeing from film top, described a plurality of plate-shaped members respectively configured in parallel form.

3. the manufacture method of optical diffusion film according to claim 2, is characterized in that, the value in the plate-shaped member that makes the adjacency in the described a plurality of plate-shaped member scope that is spaced apart 1～100mm each other.

4. the manufacture method of optical diffusion film according to claim 2, is characterized in that, while seeing from film top, described irradiation parallel light component configuration is intersected at the axis direction of described plate-shaped member and described linear light source towards.

5. the manufacture method of optical diffusion film according to claim 1, is characterized in that, described irradiation parallel light parts are aggregates of a plurality of cartridges.

6. the manufacture method of optical diffusion film according to claim 5, is characterized in that, the value in the scope that the maximum gauge that makes described cartridge is 1～100mm.

7. the manufacture method of optical diffusion film according to claim 1, is characterized in that, the value in the scope that the length from top to bottom that makes described irradiation parallel light parts is 10～1000mm.

8. the manufacture method of optical diffusion film according to claim 1, is characterized in that, makes the value in the upper end of described irradiation parallel light parts and scope that the distance between the lower end of described linear light source is 0～1000mm.

9. the manufacture method of optical diffusion film according to claim 1, is characterized in that, makes the value in the lower end of described irradiation parallel light parts and scope that the distance between described painting layer surface is 0～1000mm.

10. the manufacture method of optical diffusion film according to claim 1, is characterized in that, in described the 2nd active energy ray irradiates, making to be situated between by described irradiation parallel light parts is 10 ° of following values by the depth of parallelism of the irradiation light of parallelization.