CN1688924A - Phoretic display device with liquid crystalline suspension medium, and manufacturing method - Google Patents

Abstract

A phoretic display device comprises a plurality of electrophoretic or magnetophoretic cells, each having a phoretic particle (6) dispersed within a suspension medium (7) comprising a liquid crystal material (20). The phoretic cell is adapted to induce defects (21), sometimes known as disclinations, in the alignment of the liquid crystal material (20) within the cell which act to exert a retentive force on the phoretic particle (6) when within the region of influence of the defects (21). The configuration of the display introduces a threshold level in the electric or magnetic field required to move the phoretic particle (6) between defects (21) within the cell. Accordingly, the non-linear electro-optic or magneto-optic behavior of the display facilitates matrix addressing of the cells therein. The display may comprise a plurality of prolate spheroid phoretic cells arranged in an encapsulant the major (long) axis of each cell arranged substantially perpendicular to the plane of the display.

Description

Particle swimming display device and manufacture method thereof with liquid crystalline suspension medium

The present invention relates to particle swimming display device, exactly relate to present respectively the electrophoretic display device, EDD and the magnetophoretic display part of non-linear electric light behavior and magneto-optic behavior.The invention still further relates to manufacturing and have the method for the electrophoretic display device (EPD) of non-linear electric light behavior.

Particle swimming display typically comprises superposed layer, and this superposed layer comprises the many tiny swimming particle that is dispersed in the liquid suspension medium.By means of magnetic field or electric field are applied to device, can change the space distribution of swimming particle in superposed layer.These particles move in device under the influence of impressed field.

Conventional electrophoretic display device (EPD) comprises superposed layer, and this superposed layer comprises the many swimming particles that are dispersed in the liquid suspension medium.The principle of work of this electrophoretic display device (EPD) is that the current potential that the space distribution of swimming particle in superposed layer can be applied to device changes.This current potential is usually by being deposited on the display front and back respectively or near the electrode the front and back is applied to superposed layer.Utilize this structure, can encourage the swimming particle response in extra electric field and between the front electrode of display and backplate, move.Near the accumulation of swimming particle display front face surface or backside surface changed the light reflectance properties of superposed layer in this zone, thereby can form image by this way on display.

The general advantage of this electrophoretic display device (EPD) is can produce the image of hard contrast and need not use the polarization filter device in display device structure.

In U.S. Patent No. 3668106, described the structure and the principle of work of this electrophoretic display device (EPD) in detail.This electrophoretic display panel comprises the electrophoresis superposed layer of being made up of the fine particle that is suspended in the color electrophoresis material in the colored suspension medium in box that transparent insulation substrates that two of being formed with transparency electrode on it respectively face constitute and the described box.When DC voltage was applied to box, each particle was moved and is deposited on the electrode according to the polarity of electrophoresis material.Utilize reflected light, just observe by the formed image of the accumulation of electrophoresis material.

U.S. Patent No. 3668106 described displays present certain stability temporarily, wherein, even after extra electric field removed, the electrophoresis material of deposit still was retained on the electrode.But because electrophoresis material only is attached to electrode owing to Van der Waals attractive force and electrostatic force, so the long-term behaviour of this display is suspectable.

A major limitation of the conventional electrophoretic display device (EPD) of U.S. Patent No. 3668106 described types is that Van der Waals for can make the electrophoresis material particle in the superposed layer adhering to each other, thus the stability of infringement superposed layer.This is in long-time, because particle can cause display to lose efficacy from the superposed layer precipitation.

Do not exist Van der Waals bonding if display device is made into, it is multiplexed that then the electro-optical characteristic of display has been got rid of the matrix of each box in the display.The multiplexed a plurality of electrodes that are arranged in rows and columns respectively on the inside surface of in display, facing that typically involve of matrix.Each box in the multiplexed display of matrix is arranged is expert at and row electrode position overlapped place, and comes each box is carried out addressing by means of applying electric field via suitable row and column electrode.

Above-mentioned restriction is that the characteristic that the change by conventional granulates swimming box optical state depends on the product of time and voltage causes.That is the almost any little voltage on the box all can make it finally to change its optical states.The amplitude of impressed voltage only influences and takes place the required time of optical states change.And the effect that repeats to apply little current potential is an accumulation property, and is applied to enough accumulated voltage-seconds of given graphic elements (pixel) in the display, can change its optical states.It is multiplexed that this has hindered passive matrix.

A basic demand when display box is used in the passive matrix addressing mode is to present certain threshold value, and this is the nonlinear electric light behavior of a kind of height.When the voltage that is lower than this threshold value was applied to box repeatedly, the optical states of box must not change.But when the voltage that is higher than this threshold value (for example 2 of threshold value times) when being applied in, requires box to change its optical states rapidly.If do not satisfy this condition, then display will present serious crosstalking.That is the element that is not required to produce image can begin open-minded, but may begin to turn-off for image requires the element of part.

Although particle swimming box has above-mentioned restriction, developed certain methods threshold effect has been combined in the box.

At first, Van der Waals for can be introduced threshold effect inherently in box.But preceding paragraphs have shown Van der Waals for and have damaged the life-span of device.Therefore, for combined threshold value effect in particle swimming box, Van der Waals for does not provide feasible solution.

Utilize another example, might be connected the device that another presents non-linear electrology characteristic, thereby non-linear electric light behavior is provided with particle swimming cassette in series.This nonlinear device typically can comprise diode, Zener diode and non-linear resistance.

Unfortunately, in display, adopt nonlinear device to increase the complicacy and the cost of whole display.The reliability of display also may be owing to extra element is lowered.

As an alternative, the active matrix of thin film transistor (TFT) can be used to each box in the switch matrix display.Under the situation of the thin film transistor (TFT) that is used for the display active array addressing, transistorized physical size is to the restriction that is arranged with of pixel in the display, thereby limited exploration on display resolution ratio.

Present the electrophoretic display device (EPD) of non-linear electric light behavior inherently thereby be preferred.

In U.S. Patent No. 4305807, a kind of invention that purpose is head it off has been described.U.S. Patent No. 4305807 described displays adopt liquid crystal material as the suspension medium in the particle swimming box.The orientation that this box is configured to the liquid crystal molecule in the box can change in response to externally-applied potential.But the current potential that adds must surpass the threshold limit value level that liquid crystal molecule changes its orientation.Therefore, the desired definite threshold potential of liquid crystal molecule reorientation makes it possible to each box in the display is carried out the selection of X-Y matrix in the box.

The principle of work of this display is that the orientation along with liquid crystal molecule in the box changes owing to its anisotropic properties as the swimming particle experiences for the glutinousness of liquid crystalline suspension medium.

The reorientation of liquid crystal molecule was as one man by spatial modulation when therefore, the apparent glutinousness of suspension medium and current potential were applied to display.

When the apparent glutinousness of suspension medium was high, the motion of swimming particle in this zone of display was subjected to the obstruction of liquid crystal molecular orientation.Particle in the suspension medium mobility thereby be lowered.On the contrary, when the apparent glutinousness of suspension medium was hanged down, the motion of swimming particle in this zone of display was not subjected to the obstruction of liquid crystal molecular orientation.Under latter event, the mobility of particle is enhanced, thereby each particle can move in the suspension medium under the influence of externally-applied potential.

The anisotropy glutinousness of liquid crystalline suspension medium provides a kind of mechanism to control the motion of swimming particle in display.

Select though U.S. Patent No. 4305807 makes it possible to that each box in the electrophoretic display device (EPD) is carried out the X-Y matrix, the performance of display may be subjected to the restriction of used structure.For example, the apparent glutinousness of liquid crystalline suspension medium only hinders in the display swimming particle response and does not get rid of the motion of swimming particle in the migration of extra electric field in the display.Therefore, display still may present crosstalking to a certain degree.

EP 1154312 has described the light shutter device of a kind of structural similarity in U.S. Patent No. 4305807 used structures.EP 1154312 described light shutter devices comprise a kind of insoluble photocontrol medium that is dispersed in the liquid crystal material.Identical with U.S. Patent No. 4305807, the electric field that is applied to device causes that the orientation of the liquid crystal molecule in the liquid crystal material changes, thereby the photocontrol medium in the device can be moved.This distribution density that causes photocontrol medium in the liquid crystal material layer changes.

Form contrast with U.S. Patent No. 4305807, the main cause of photocontrol medium motion is flowing of the liquid crystal material that brought out by the electric field that is applied to device.This flow typically by known to cause the ion of liquid crystal material long-term degradation to be injected in the liquid crystal causing.

The objective of the invention is to improve at least some shortcoming of aforementioned display device, and a kind of electrophoretic display device (EPD) that has improved is provided.Another object of the present invention provides a kind of electrophoretic display device (EPD) that can select to carry out addressing with the X-Y matrix of each box in the device that presents non-linear electric light behavior.A further object of the present invention provides the method that a kind of manufacturing has the electrophoretic display device (EPD) of non-linear electric light behavior.

According to first situation of the present invention, particle swimming box comprises the liquid crystal cell that wherein has liquid crystal material and swimming particle, and this swimming particle can move to second side of liquid crystal cell from first optimum position of liquid crystal cell first side when applying the outfield.

Liquid crystal cell is selected to when the swimming particle is not positioned at the first optimum position place; exist a kind of defective relevant with first optimum position; and when the swimming particle is located substantially on the first optimum position place in the liquid crystal cell, lower when the Defects of Liquid energy of this defective is not located like this than swimming particle.

In a preferred embodiment, for the swimming particle is moved to second side of liquid crystal cell from first optimum position, impressed field must surpass certain threshold level.

Be sometimes referred to as the defective of disclination, can be envisioned as the uncontinuity of the liquid crystal molecular orientation that is described as liquid crystal aligning.In the immediate area around the defective, liquid crystal alignment is seriously distorted from the parallel everywhere minimum energy state of directed son wherein.Therefore, exist the relevant elastic energy of a large amount of defectives therewith.For the purpose of patent specification, this elastic energy will be called as the defective energy.

Depend on the defective distortion type of liquid crystal on every side, defective can be got different forms.Typically by the wrapped path rotation of enclosing defective of the orientation of liquid crystal aligning what and along what direction rotation, come defective is classified.Can determine the sign defective by this way, wherein directed son is around opposite direction rotation, and the degree of rotation is determined amplitude.This numerical value is considered to the intensity of defective, and can be positive or negative.The defective of two kinds of opposite in signs will attract each other, and will reduce its elastic energy mutually by means of mobile its center.This attraction can proceed to two defect centers continuously and be combined into the defective that intensity equals the summation of original two defective intensity; Thereby negative intensity and positive intensity are offset.Under the equal and opposite situation of the intensity of two defectives, then two defectives fall into oblivion each other effectively, no longer have residual defects.

Defective in the liquid crystal material is configured to attract to be dispersed in swimming particle wherein; Each defective causes relevant range of influence in liquid crystal material.In case be in the specific range of influence, the swimming particle just is attracted the relevant defective in this range of influence of trend.If not interrupted, then the swimming particle can move in the range of influence, so that select an elastic energy that causes owing to defective to be reduced to minimum optimum position.

Relation between the optimum position (for example first optimum position) in the box that term " relevant " be used to describe the in front caused range of influence of defective in defective, the box and described defective cause.This term has been used to pass on such fact, promptly in some cases, because particle may be stopped that particle possibly can't arrive the position of defect center by the box wall.But still exist and make system resilience can be kept to minimum particle position.

In some cases, but be not exclusiveness, the obstruction of above-mentioned box wall may be because defective is " virtual ".Virtual defective is that wherein the defect center is in fact in liquid crystal area outside, but it is still exerted one's influence to the behavior of liquid crystal.This influence is caused by the aligning that virtual defective is hidden in the liquid crystal of surface wherein.Virtual defective typically can appear in the faint or surperficial situation about tilting in advance with non-zero of surface anchoring energy.

For the purpose of clear, with reference to a kind of defective, described defective can be virtual defective or the interior normal defect of liquid crystal material that is hidden in the surface in patent specification.

Below, the optimum position in the box that each defective in the system will similarly be described as causing with described defective is relevant.

In the present invention, near the aligning of its liquid crystal material has been upset in the existence of swimming particle, and therefore, this swimming particle plays mobile defective or defective set in the system.

Under the situation of this liquid crystal cell, defective relevant with first optimum position and the defective of being correlated with the swimming particle are arranged to have opposite symbol.Therefore, these defectives attract each other, and by means of the motion of swimming particle, can reduce their elastic energy.

In the time of in the swimming particle is in the liquid crystal material body, the swimming particle more freely moves under the influence of impressed field.But when particle was in the liquid crystal material in another defect influence zone, interacting just appeared between these defectives, thereby reduced the Defects of Liquid energy relevant with described these defectives.

Therefore, when relevant defective was overlapping when the defective relevant with the swimming particle and with first optimum position, the Defects of Liquid energy of the defective relevant with first optimum position was reduced to minimum.Under the situation that the geometric configuration of system allows, these defectives so degree that interacts falls into oblivion effectively to such an extent as to we can say them.In the case, term " defective " refers to the core of the original appearance fault location relevant with first optimum position.

Therefore, first optimum position can be associated defective or defective set and the defective position overlapped relevant with the swimming particle.But it is this overlapping that the geometric configuration of the geometric configuration of liquid crystal cell and swimming particle may not allow.In the case, the Defects of Liquid energy is reduced to minimum swimming particle position (i.e. first optimum position) and will be positioned near this defective, and will be by the geometric configuration decision of liquid crystal cell.

The invention provides following advantage, when promptly relevant defective interacts when the defective relevant with the swimming particle with first optimum position, the swimming particle will tend to attracted to first optimum position and be attached to first optimum position.And, moving to second side of liquid crystal cell in order to make the swimming particle from first optimum position, impressed field must surpass threshold level in time enough.This provides and has been used for making swimming particle first optimum position from liquid crystal cell to move to the nonlinear characteristic of second side of liquid crystal cell.

The swimming particle is preferably under the impressed field first optimum position that can reverse second optimum position from liquid crystal cell second side moves to the liquid crystal cell first side place.

This liquid crystal cell is employed as when the swimming particle is not positioned at second optimum position; exist the defective relevant with second optimum position; and when the swimming particle was located substantially in the liquid crystal cell the second optimum position place, the Defects of Liquid energy of this defective was lower than the energy when the swimming particle is not located like this.

In a preferred embodiment, for the swimming particle is moved to first optimum position in the liquid crystal cell from second optimum position, impressed field must surpass threshold level.

Therefore, with similar in appearance to above-mentioned mode, when relevant defective was overlapping when the defective relevant with the swimming particle with second optimum position, the Defects of Liquid energy relevant with second optimum position can be reduced to minimum.Under the situation that the geometric configuration of system allows, these defectives so degree that interacts falls into oblivion effectively to such an extent as to we can say them.In the case, term " defective " refers to the core of the original appearance fault location relevant with second optimum position.

By means of the polarity of counter-rotating impressed field, the swimming particle can be transferred to second optimum position from first optimum position, and vice versa.

This embodiment of the present invention provides following advantage, and promptly when the defective relevant with the swimming particle interacted with the defective relevant with second optimum position, the swimming particle tended to attracted to second optimum position and adheres to second optimum position.Therefore, in this embodiment of the present invention, the swimming particle can be between two settling positions, that is the first and second optimum position places in liquid crystal cell move respectively.

And for the swimming particle is moved to first optimum position from second optimum position in the liquid crystal cell, impressed field must surpass threshold level in the enough time.This provides the nonlinear characteristic that the swimming particle is moved to first optimum position in the liquid crystal cell from second optimum position in the liquid crystal cell.This structure also provides following advantage, and promptly by means of the counter-rotating impressed field, the swimming particle can oppositely move between first and second optimum positions in liquid crystal cell on the contrary.

Advantageously, move to the amplitude of the relevant threshold level of second optimum position with the swimming particle from first optimum position in the liquid crystal cell, be different from the amplitude that moves to the relevant threshold level of first optimum position with the swimming particle from second optimum position in the liquid crystal cell.

The difference of above-mentioned threshold level amplitude has caused depending on the asymmetric switching threshold of the polarity of impressed field on the liquid crystal cell.Under the situation of requirement of the polarity that exists a plurality of this particle swimming boxes of control, for example in many boxes display, thisly asymmetricly made things convenient for the demultiplexing matrix addressing, and make it possible to so-called row in advance the technology of blank come these boxes are carried out addressing.

In a preferred embodiment, particle swimming box has a plurality of first optimum positions at the first side place of liquid crystal cell, and each first optimum position has relative defective, and has a plurality of swimming particles that are dispersed in the liquid crystal material.Particle swimming box can have a plurality of second optimum positions at the second side place of liquid crystal cell, and each second optimum position has relative defective.At least one inside surface of liquid crystal cell can be shaped to and bring out described defective.

When constituting as mentioned above, each swimming particle can move between relative first and second optimum positions in the particle swimming box, thereby box can be by this way by spatial modulation.Above-mentioned particle swimming box thereby can be used as many boxes particle swimming display.

The benefit of this embodiment of the present invention is, has brought out defective by means of at least one inside surface of shaping liquid crystal cell with controllable mode.For the preferred orientation of liquid crystal material is provided, surperficial registration process method also can be applied at least one inside surface of liquid crystal cell.For example, can adopt the surperficial registration process of the anchoring condition that provides non-perpendicular basically.The sub-tangential component of excitation liquid crystal aligning provides surface treatment inclination or isoplanar aligning, is a kind of suitable surface treatment.The surface registration process also can be applied to the swimming particle in the liquid crystal cell.And, provide the surperficial registration process of non-perpendicular basically anchoring condition can be used to the swimming particle.

Advantageously, this shaping comprises a plurality of depressions that are arranged in array.

These depressions are aligned to regular array usually.

This array comprises a two-dimensional array usually, and each depression is aligned to the solid matter structure.Each is recessed in can be arranged to six side's solid matter structures in the array.For the purpose of clear, the arrangement of array sunken inside is described with term solid matter and six side's solid matters herein, it is similar using to its routine in describing crystalline network.

These depressions preferably comprise the depression of semielliptical basically.

More preferably, these depressions comprise the depression of semielliptical shape basically.

Advantageously, these depressions comprise the depression of semicircle sphere basically.

More advantageously, these depressions comprise the depression of half ball basically.

Used prefix " partly " is used to define the partial geometry shape of its indication in this instructions, is not limited to half, and for example, semisphere should be the part (described part is not limited to half) of definition ball.Partly comprise in geometric configuration under half the situation basically of described shape, had precedence over herein then more generally that prefix " partly " (semi) has adopted prefix " half " (hemi), for example term " half ball " should define half of ball basically.

Each is recessed in and preferably is aligned to spacing in the array is p, and the degree of depth of each depression is d.For the purpose of clear, below used term spacing should refer in the regular array distance between each depression in succession.

More preferably, the depth d of these depressions is at least 1/4 to the ratio of spacing p.

In a preferred embodiment, the spacing p of these depressions is the 2-50 micron.

The spacing p of these depressions is preferably the 3-30 micron.

More preferably, the spacing p of these depressions is the 4-15 micron.

In a preferred embodiment, the diameter of swimming particle is that 0.5-0.9 is doubly to the spacing p of these depressions.

The diameter of swimming particle is preferably 0.7-0.8 doubly to the spacing p of these depressions.

Comprise under the situation of single swimming particle at particle swimming box, liquid crystal cell can comprise a liquid crystal tear drop.Advantageously, particle swimming box comprises a plurality of liquid crystal cells, and each liquid crystal cell comprises a liquid crystal tear drop.

Liquid crystal cell arrangement with the form of a liquid crystal tear drop or a plurality of liquid crystal tear drops has made things convenient for the production of described liquid crystal cell.

These liquid crystal tear drops can be spheroidal, and the length L of each liquid crystal tear drop equals the diameter D of tear drop.

Usually, the liquid crystal tear drop is the sphere of prolate basically, and each liquid crystal tear drop is L along the length of liquid crystal tear drop major axis, be D along the diameter of minor axis, and first and second optimum positions is arranged on the contrary along the major axis of each liquid crystal tear drop basically.

In a preferred embodiment, the length L of liquid crystal tear drop is the 1-30 micron.

The length L of liquid crystal tear drop is preferably the 5-20 micron.

More preferably, the length L of liquid crystal tear drop is the 10-15 micron.

In a preferred embodiment, the diameter of swimming particle is that 0.2-0.8 is doubly to the diameter of liquid crystal tear drop.

The diameter of swimming particle is preferably 0.3-0.7 doubly to the diameter of liquid crystal tear drop.

More preferably, the diameter of swimming particle is that 0.4-0.6 is doubly to the diameter of liquid crystal tear drop.

Advantageously, this liquid crystal cell or each liquid crystal cell comprise dyestuff.Usually, this liquid crystal cell or each liquid crystal cell comprise oil-soluble dyestuff.It is one of following at least that this dyestuff can comprise: dichroic dye, azo dyes, anthraquinone dye, the medicine dyestuff, cosmetic dyes, food dye, 1-hydroxyl-4-[(4-aminomethyl phenyl) amino]-9, the 10-amerantrone, 2-(2-quinolyl)-1,3-indenes diketone, 1, two [(4-aminomethyl phenyl) amino]-9 of 4-, the 10-amerantrone, 1-[[4-(phenylazo) phenyl] azo]-2 naphthalene enols, solvent black 3, solvent black 5, solvent black 7, solvent black 12, solvent black 28, solvent blue 4, solvent blue 19 4, solvent blue 19, solvent blue 29, solvent blue 35, solvent blue 36, solvent blue 37, solvent blue 38, solvent blue 43, solvent blue 59, solvent blue 78, solvent blue 97, solvent blue 19 04, solvent brown 1, solvent brown 53, solvent green 1, solvent green 3, solvent green 4, solvent green 5, solvent green 7, solvent green 11, solvent green 28, solvent orange 1, solvent orange 2, solvent orange 7, solvent orange 15, solvent orange 20, solvent orange 23, solvent orange 60, solvent orange 63, solvent orange 105, solvent red 3, solvent red 19, solvent red 23, solvent red 24, solvent red 26, solvent red 27, solvent red 41, solvent red 43, solvent red 44, solvent red 45, solvent red 49, solvent red 72, solvent red 111, solvent of red 135, solvent red 140, solvent red 179, solvent red 195, solvent red 207, solvent purple 8, solvent violet 13, solvent violet 37, solvent violet 59, solvent yellow 1, solvent yellow 2, solvent yellow 3, solvent yellow 7, solvent yellow 14, solvent yellow 33, solvent yellow 72, solvent yellow 93, solvent yellow 94, solvent yellow 98, solvent yellow 114, solvent yellow 141, solvent yellow 16 0, solvent yellow 16 3.

In a preferred embodiment, this swimming particle or each swimming particle are used to reflect the electromagnetic radiation of incident on it.

Advantageously, this swimming particle or each swimming particle have and comprise the reflective coating of one of metallic coating and dielectric coated at least.

In a further preferred embodiment, this swimming particle or each swimming particle comprise a kind of composite particles, and this composite particles has a plurality of scattering particles that are used for scattering electromagnetic radiation of incident on it that are dispersed in the carrier.This carrier can comprise polymkeric substance, for example polymethylmethacrylate (PMMA).These scattering particles can comprise titania (TiO ₂).As an alternative, or in addition, scattering particles can comprise the polymkeric substance ball, and each polymkeric substance ball is incorporated into one of adamas of weak breath body cavity or pulverizing.

It is maximum that this compound swimming particle makes scattering of light, thereby good reflectivity is provided.When particle swimming box was used to display device, this was a kind of desirable especially character.

Impressed field can be one of electric field and magnetic field at least.

According to second situation of the present invention, have a plurality of first optimum positions at the liquid crystal cell first side place and have a plurality of manufacture methods that are suspended in the particle swimming box of the swimming particle in the liquid crystalline suspension medium, comprise the following step:

(i) preparation first substrate, it has and is used for interacting with the first releasing structure alignment of preferred alignment that liquid crystal aligning in the particle swimming box is provided with liquid crystalline suspension medium,

(ii) form a plurality of depressions in the releasing structure alignment, each depression has the inside surface that extends from the releasing structure surface of releasing structure alignment,

(iii) the swimming particle is deposited on the first releasing structure surface,

(iv) liquid crystalline suspension medium is combined in the box.

Advantageously, have at particle swimming box under the situation of second optimum position at the box second side place, the method also comprises the following step:

(v) prepare second substrate, it has and is used for interacting with the second releasing structure alignment of preferred alignment that liquid crystal aligning in the particle swimming box is provided with liquid crystalline suspension medium,

(vi) form a plurality of depressions in the second releasing structure alignment, each depression has the inside surface that extends from the releasing structure surface of the second releasing structure alignment,

(vii) second substrate is arranged in away from first substrate, its releasing structure alignment and liquid crystalline suspension medium are interacted, so that the preferred alignment of liquid crystal aligning in the particle swimming display is provided.

The method preferably comprises each depression in the releasing structure surface of the first releasing structure alignment is arranged to the step that the respective recesses in the releasing structure surface with the second releasing structure alignment is faced basically, and it is right that described each is recessed to form the depression of facing.

More preferably, the method comprises the swimming particle is arranged in the internal step of each depression of facing.

Usually, one of at least the first and second substrates comprise one of polymkeric substance and prepolymer at least, and the step that forms a plurality of depressions in the releasing structure surface comprises embossed technology.

As an alternative, one of at least the first and second substrates comprise photopolymer, and the step of a plurality of depressions in the formation releasing structure surface comprises photoetching process.

According to the 3rd situation of the present invention, a kind of display has been proposed, first display surface that it has the displayed image of being used for comprises the particle swimming box of first situation according to the present invention,

Wherein, particle swimming box is arranged in the display, makes first optimum position or each first optimum position in the liquid crystal cell be located substantially on the first display surface place.

By means of applied field on display, this display can be worked.

The arrangement of display endoparticle swimming box provides following advantage, and promptly when being positioned at this first optimum position of liquid crystal cell or each first optimum position place, this swimming particle or each swimming particle reflect the light that is incident on first display surface.

The particle swimming box that is included in the display is worked in the mode identical with the present invention's first situation.In use, for the swimming particle is moved to second side of liquid crystal cell from first optimum position, or move to second optimum position in the liquid crystal cell, what be applied to display must surpass threshold level in time enough.

Have under the situation of first and second optimum positions at particle swimming box, in order to influence the transfer of particle between optimum position, only the swimming particle is moved to the zone of influence relevant with second optimum position from the zone of influence relevant with first optimum position just enough.As mentioned above, this is because in case in the specific zone of influence, the swimming particle just is attracted trend and causes the defective of this zone of influence.If not interrupted, then the swimming particle will move in the zone of influence, so that select one because the elastic energy of this defective is reduced to minimum optimum position.

This provides a kind of nonlinear characteristic, is used for the swimming particle is moved to second optimum position in the second side/liquid crystal cell of liquid crystal cell from first optimum position in the liquid crystal cell.

In a preferred embodiment, display has second display surface of arranging away from first display surface, and comprises at least one particle swimming box, and this particle swimming box has second optimum position at the second side place of liquid crystal cell,

Wherein, particle swimming box is arranged in the display, makes this second optimum position or each second optimum position in the liquid crystal cell be located substantially on the second display surface place, and

First and second optimum positions can be seen this swimming particle or each swimming particle at the display surface place when being positioned at an optimum position place, and can't see at described display surface place when being positioned at another optimum position place.

This structure of display endoparticle swimming box provides following advantage; promptly when being positioned at an optimum position place; this swimming particle or each swimming particle reflect the light that is incident on the specific display surface; but when being positioned at another optimum position place, the light that is incident on this specific display surface is not reflected.Therefore, one or more swimming particles can be seen at given display surface place, perhaps, one or more particles can be arranged to this particle or each particle and can not see at described display surface place.

As mentioned above, the particle swimming box that is included in the display is worked in the mode identical with the present invention's first situation.In use, for the swimming particle is moved to first optimum position in the liquid crystal cell from second optimum position, the field that is applied to display must surpass threshold level.This provides a kind of nonlinear characteristic, is used for the swimming particle is moved to first optimum position in the liquid crystal cell from second optimum position in the liquid crystal cell.

In another preferred embodiment, display comprises the particle swimming box with a plurality of liquid crystal cells, and each liquid crystal cell comprises the liquid crystal tear drop, and wherein, the liquid crystal drop integument is placed in the encapsulation agent.

In this embodiment of the present invention, display can comprise little display of sealing.For example, display can comprise the LCD of polymer dispersed.

But encapsulation agent can comprise at least a in heat-setting polymkeric substance electromagnetic radiation cured polymer and the silicone synthetic rubber.For example, this encapsulation agent can comprise DowCorning Sylgard 182.

Advantageously, this display comprises the particle swimming box with a plurality of liquid crystal tear drops, and wherein, the liquid crystal tear drop is the spheroid of prolate basically, and the major axis that is aligned to each liquid crystal tear drop is substantially normal to the plane parallel with first display surface.

This display preferably also comprises be used for applying the device of one of electric field and magnetic field at least on display.For example, being used for the device of applied field can comprise electrode.

This display preferably comprises near the row that is arranged in first display surface and a plurality of electrodes near the row second display surface, the intersection point of each row and column electrode is determined a pixel in the display, so that can carry out matrix addressing to each pixel in the display.

This electrode or each electrode can comprise at least a in metal, tin indium oxide (ITO) and the conducting polymer.

According to the 4th situation of the present invention, the manufacture method of the display of second situation comprises the following step according to the present invention:

(i) a plurality of liquid crystal cells are distributed in the curable encapsulation agent, each liquid crystal cell comprises aforesaid liquid crystal tear drop,

(ii) each liquid crystal cell is aligned to preferred alignment,

(iii) encapsulation agent is cured, so that each liquid crystal cell is clamped in wherein.

Advantageously, the method also is included in the step of carrying out brilliant box of spreading liquid and curable encapsulation agent on the substrate.

Preferably after being cured, encapsulation agent carries out each liquid crystal cell is aligned to the step of preferred alignment, and comprise the encapsulation agent that expands and be cured along the direction that is substantially perpendicular to substrate, thereby be dispersed in the step of liquid crystal cell wherein along the direction elongation that is substantially perpendicular to substrate.The step of the encapsulation agent that expansion is cured can comprise material is incorporated in the encapsulation agent of curing, heaves so that cause the encapsulation agent that is cured.The expansion of encapsulation agent forces each liquid crystal cell to select the spherical structure of prolate basically.In addition, the main shaft of each liquid crystal cell is aligned to and is substantially normal to the plane parallel with substrate.

As an alternative, the method comprises some intermediate steps, promptly before solidifying encapsulation agent, in substrate plane, make reversibly deformation of substrate, after solidifying encapsulation agent, make substrate get back to it then not by the state of deformation, so that carry out the step of aiming at liquid crystal cell, the encapsulation agent of curing be compressed in the plane parallel with substrate plane with the liquid crystal cell that is dispersed in wherein.

In the plane parallel, liquid crystal cell is compressed, cause that each liquid crystal cell selects the spherical structure of prolate basically with substrate plane.In addition, the main shaft of each liquid crystal cell is aligned to and is substantially normal to the plane parallel with substrate.

Usually, the step that substrate is carried out reversible deformation comprise to substrate heat and stretch at least a.

Referring now to accompanying drawing, only the present invention is described with the method for giving an example, in these accompanying drawings:

Fig. 1 shows the constructed profile of conventional electrophoretic display device (EPD) common in the prior art,

Fig. 2 shows the synoptic diagram of the conventional electrophoretic display device (EPD) that is used for showing letter-numerical character,

Fig. 3 shows the surface that is applicable to according to electrophoretic display device (EPD) of the present invention and discharges synoptic diagram.For the purpose of clear, from figure, omitted and be used for current potential is applied to the device of display.

Fig. 4 shows according to elastic energy in the particle swimming box of the present invention and function relation curve from the distance of wherein defective.In this example, particle swimming box comprises individual defect and single swimming particle.

Fig. 5 shows the constructed profile according to bistable electrophoretic display device (EPD) of the present invention.For the purpose of clear, from figure, omitted and be used for current potential is applied to the device of display.

Fig. 6 shows the function relation curve according to the distance between the elastic energy in bistable of the present invention or the multistable particle swimming box and two the opposite defectives.In this example, particle swimming box comprises two opposite defectives and is arranged in therebetween single swimming particle.

Fig. 7 shows according to little constructed profile of sealing electrophoretic display device (EPD) of the present invention.For the purpose of clear, show the single little tear drop of sealing in the display.Illustrated little seal in the tear drop and the electrophoresis material particle on liquid crystal aligning aim at.

Fig. 8 shows little electrophoretic display device (EPD) constructed profile in the course of the work of sealing.For the purpose of clear, the single little tear drop of sealing in the display has been shown in Fig. 8 a-8d.

Fig. 9 shows the constructed profile of compound swimming particle.

Figure 10 shows preparation and is used for being combined to little technology of sealing the electrophoresis material particle in the electrophoretic display device (EPD).Figure 10 a is a process flow diagram, shows to be used for hydrophobicity is given the technology of electrophoresis material particle.Figure 10 b is a process flow diagram, shows the manufacturing process of combination by the compound swimming particle of the hydrophobic particle that technology produced of Figure 10 a.

Figure 11 process flow diagram shows and is used for little preparation technology who seals the capsule and pill that comprises liquid crystal (wherein being dispersed with the swimming particle) of electrophoretic display device (EPD).

Figure 12 process flow diagram shows and is used for little a kind of flexible preparation technology who seals the capsule and pill that comprises liquid crystal (wherein being dispersed with the swimming particle) of electrophoretic display device (EPD).

Figure 13 journey illustrates little manufacturing process of sealing electrophoretic display device (EPD) of the capsule and pill of combination Figure 12 technology generation.

Figure 14 shows according to little local constructed profile of sealing electrophoretic display device (EPD) of the present invention.

With reference to Fig. 1, conventional electrophoretic display device (EPD) (1) comprises by being formed with transparency electrode (4a on it respectively, two transparent insulation substrates of facing 4b) (3a, 3b) the electrophoresis superposed layer of forming by the fine particle that is suspended in the electrophoresis material (6) in the suspension medium (7) in box of Zu Chenging (2) and the box (5).Typically, electrophoresis material (6) particle is arranged to become with the medium that suspends (7) color the color of contrast.When current potential (8) is applied to box (2), according to the polarity of electrophoresis material (6), swimming particle (6) be moved and be deposited on an electrode (4a, 4b) on, and utilize reflected light (10) to observe the image (9) of such formation.The thickness of superposed layer (5) can be from several microns to tens microns, and this display is worked with DC voltage usually.

In practice, the transparent insulation substrate in the box (3a, 3b) can by separate about 50 microns and in the edge two sealed glass sheet form.(4a 4b) can be made up of transparent tin indium oxide (ITO) layer electrode on the glass sheet inboard.

If swimming particle (6) be micron-scale and density can with the analogy of the density of liquid suspension medium (7), then they can remain in the time that prolongs in the suspending liquid and not be precipitated out.In aforementioned display device was used, liquid suspension medium (7) can be dyed dark slightly color, for example black.Say that typically swimming particle (6) is the contrast colors of the color of liquid suspension medium (7).For example, titania provides good reflexive high scattering power and can be used as electrophoresis material owing to it.

Under unexcited state, box manifests black, that is the color of liquid suspension medium (7).(4a, in the time of 4b), (3a 3b) move, and (3a, outward appearance 3b) changes over white to swimming particle (6) to make this substrate wall towards a substrate wall when current potential (8) is applied to the electrode of facing.If remove current potential (8) now, then particle owing to Van der Waals attractive force and electrostatic force stay on the substrate wall (3a, 3b) on.With externally-applied potential (8) counter-rotating, then cause and leave the substrate wall by swimming particle (6) (3a 3b), and advances towards the substrate wall of facing.

With reference to Fig. 2, (3a, 3b) (4a 4b) is in character (11) shape to the electrode on, and this character (11) is alternately manifested with the said sequence of externally-applied potential (8) as if a substrate wall.Having made each display that is used for the laboratory demonstration has the simple displaying device of several letter-numerical characters (11).In all cases, each section (12) of each character (11) comes individual drive by discrete driving circuit (13) or a plurality of driving circuit.

It is multiplexed that the normal electric light behavior of this display (1) can not be carried out the matrix of box usually.This characteristic that is change by particle swimming box (2) optical states depends on the product of time and voltage causes.That is almost any little voltage all can cause its final its optical states that changes on the box.

But this device can be designed to have huge Van der Waals for particle adhesion to substrate and or adhering to each other so that certain threshold value behavior to be provided.This adhesion is then very responsive to staiing, and the common ultimate failure of the suspension of particle, causes the flocculation of particle, and entire device was lost efficacy.

With reference to Fig. 3, an embodiment according to electrophoretic display device (EPD) of the present invention comprises a kind of electrophoresis system, wherein, electrophoresis material particle (6) is suspended in the suspension medium (7) that comprises liquid crystal material (20), and wherein the geometric configuration of system is arranged to induced defect (21) in liquid crystal material (20).Defective (21) can be envisioned as liquid crystal material (20) and be orientated symmetric local failure, for example the local failure of the sub-orientation order of liquid crystal aligning.This defective (21) is called as the disclination in the liquid crystal material (20) sometimes.

Defective (21) in the liquid crystal material (20) is configured and attracts the swimming particle; Each defective (21) causes a relevant zone of influence in liquid crystal material (20).

In this structure, the existence of electrophoresis material particle (6) distorts near the aligning of liquid crystal material (20) particle (6), particle (6) thereby play movably defective (21) or the defective set in system.When the electrophoresis material particle was in the bulk suspension medium (7), they are motion more freely under the influence of externally-applied potential.But when particle was in the zone of influence of the defective (21) in the liquid crystal material (20), interacting just occurred between defective (21) and the swimming particle (6), particle (6) thus the defective of being correlated with towards the zone of influence therewith is attracted.If do not hindered, then swimming particle (6) will move in this zone of influence to select elastic energy in the system that a defective (21) causes to be reduced to the optimum position of minimum.

When particle (6) and defective (21) were as close as possible and overlapping in some cases, intrasystem total Defects of Liquid can be reduced to minimum, in the case, has fallen into oblivion defective or disclination effectively.When defective (21) interacts or fall into oblivion, particle (6) will tend to adhere to the place (hereinafter referred to as defective nuclear) that occurred or occurred defective (21) in the display originally.

Under the non-existent situation of externally-applied potential, electrophoresis material particle (6) will tend to remain on the optimum position place of closing with the defective nuclear phase.This is to compare because of being in the brilliant material of body fluid (20) with particle (6), and the energy of material is lower in this structure (particle (6) is near defective nuclear or on the top of defective nuclear).This provides following advantage, promptly with electrophoresis material only owing to the conventional electrophoretic display device (EPD) that Van der Waals attractive force and electrostatic force adhere to display surface is compared, the long-time stability of the image that device shows are improved.The flocculation of swimming particle also has been lowered, thereby has improved the life-span of device.

For electrophoresis material particle (6) is moved from the optimum position with defective nuclear phase pass, the current potential that must will be enough to overcome the potential barrier relevant with separating each defective (21) is applied to display, that is, under the situation that defective has been fallen into oblivion, externally-applied potential must locate to form again defective (21) at defective nuclear place and electrophoresis material particle (6).

As mentioned above, defective is interact with each other, so that reduce the elastic energy of liquid crystal.Therefore, the defective relevant with particle (6) be subjected to liquid crystal cell in the relevant defect influence of optimum position.Usually, in any one specific zone of liquid crystal cell, a specific defective will be preponderated.By this way, by means of particle (6) is moved towards the defective with the opposite intensity of defective relevant with particle (6), the elastic energy of system just is lowered.For particle (6) is separated from the defective that attracted on it, must utilize externally-applied potential to finish opposite merit.In theory, enough merits of utilizing externally-applied potential to finish, particle (6) can be moved to from the defective relevant with optimum position the liquid crystal cell the insignificant liquid crystal cell of the influence of particle zone.If the underswing of impressed field, or if impressed field only the short time apply, cause particle still in the specific zone of influence, then this particle is got back to its initial position with relaxation.This threshold value behavior is given display with non-linear electrooptical property, makes the passive matrix addressing of device become possibility.

Fig. 4 shows according to elastic energy in the particle swimming box of the present invention and function relation curve from the distance of one of them defective.Curve representation among Fig. 4 a kind of particle swimming box, it comprises individual defect and has single swimming particle.In the case, exist in box the single zone of influence of extending from defective (21) wherein.In practice, this zone of influence can extend beyond 50 microns from defective (21).

When electrophoresis material particle (6) is in the zone of influence of defective (21) with stressed.As if the symbol of the defective that particle is relevant therewith and the opposite in sign of defective nuclear, then this power can attract particle (6) towards defective nuclear (21).If do not hindered, then swimming particle (6) can move in the zone of influence, so that the elastic energy owing to defective (21) is reduced to a minimum optimum position (first optimum position) in the selective system.

About particle swimming box shown in Figure 4, can examine the maximum distance that move (21) from defective by means of restriction particle (6), can access a kind of monostable structure.Limit the motion of particle (6) in the zone of influence by this way, guaranteed that particle (6) turns back to first optimum position under the situation that does not have externally-applied potential.

For the purpose of clear, should be noted that the apparent viscosity that the present invention changes the interior liquid crystal material of suspension medium (7) (20) not obviously provides non-linear electric light behavior (forming contrast with the U.S. 4305807 of previous discussion).In the present invention, the liquid crystal material (20) that is aligned to really in the suspension medium (7) of liquid crystal aligning always shows its minimum viscosity.And with regard to the aligning that changes liquid crystal aligning, particle swimming box according to the present invention is applied the effect that electric field produces can be ignored.Equally, defective (21) in this particle swimming box or disclination since be produce by the geometric configuration of system thus be pinned at effectively in the particle swimming box and still be not subjected to the influence of externally-applied potential.

Referring now to Fig. 5, the defective (21) by means of arranging on the opposed face in electrophoretic display device (EPD) in the liquid crystal material (20) can produce a kind of bi-stable display.For example, first group of defective (21) is arranged on the surface, first (front) (24) of display, and second group of defective (21) is arranged on the surface, second (back side) (26) of display.In this embodiment, by means of the current potential that applies above threshold level, the first surface (24) that electrophoresis material particle (6) can be energized from display is moved to second surface (26) (vice versa).

Identical with Fig. 3, for particle (6) is separated from the defective that it attracted on it, must utilize externally-applied potential to come work done.Enough merits of utilizing externally-applied potential to finish, particle (6) can be moved to the dominant liquid crystal cell of another defective zone.Particle (6) then will relax towards a reposition in the box, and this reposition is the relevant optimum position of new therewith defective.In case reach maximum effect district of this second defective, just no longer require electric field to be applied to box.By this way, far away for particle (6) is moved enough from its initial position, so that relax towards reposition in the box, require the threshold value of externally-applied potential.As previously described, if apply not enough field, then particle (6) is got back to its initial position with relaxation.

Fig. 6 shows the function relation curve according to the distance between the elastic energy in bistable of the present invention or the multistable particle swimming box and two the opposite defectives.

Curve representation among Fig. 6 a kind of particle swimming box, it comprises two opposite defectives (21), and has the single swimming particle (6) that is arranged in therebetween.In the case, exist in box from first zone of influence that first defective nuclear (21) extends and second zone of influence of in box, examining (21) extension from second defective.

As discussed previously, when in the specific effect district relevant with defective (21), electrophoresis material particle (6) is with stressed.If the symbol of the defective that particle (6) is relevant and defective are examined the opposite in sign of (21) therewith, then this power can be attracted to particle (6) defective nuclear (21).If do not hindered, then swimming particle (6) can move in the zone of influence, so that the elastic energy owing to defective (21) is reduced to a minimum optimum position (being first or second optimum position in the case) in the selective system.

Say that typically in any specific region of liquid crystal cell, a specific defective can be preponderated.Therefore, when particle (6) was in first zone of influence, it can be attracted towards first defective nuclear (21).Equally, when particle (6) was in second zone of influence, it can be attracted towards second defective nuclear (21).

Find that when particle (6) was positioned at the equilibrium point place of two defectives, the proof resilience of system can be the highest, and when particle (6) when any one defective moves, the proof resilience of system can reduce.

In the described structure of Fig. 6,, only move to the zone of influence of second defective nuclear phase pass just enough from the zone of influence swimming particle (6) with first defective nuclear phase pass in order to influence the transfer of particle between optimum position.As discussed previously, this is because in case in the specific zone of influence, the swimming particle just is attracted towards the defective that causes this zone of influence.

The current potential that is applied to box must surpass the interior energy barrier of particle swimming box, and must apply the time span that is enough to particle (6) is transferred to from a zone of influence another zone of influence.

By this way, the non-linear electric light behavior that presents of particle swimming box is the function of amplitude (E) that is applied to the current potential of box and the time (t) that applies current potential.Therefore, particle swimming box presents a static threshold relevant with the externally-applied potential amplitude and one and multiply by the relevant dynamic threshold of externally-applied potential amplitude (time voltage product) with the time that applies current potential.

This dynamic threshold is similar to some conventional non-electrophoresis liquid crystal device, for example the threshold value that is experienced in the ferroelectric display of surface-stable, Zener bistable device (ZBD) and the Nemoptic BiNem bi-stable liquid crystals display.

This bi-stable display provides following advantage, and promptly when device not being applied current potential, electrophoresis material particle (6) still is strapped in defective nuclear place.And even when having low level current potential (being lower than the threshold level of device), electrophoresis material particle (6) still is strapped in defective nuclear place basically.Because this current potential is intrinsic in multiplexed addressing scheme, so this is favourable.Therefore, by means of reducing the undesirable migration of electrophoresis material particle (6) in device, guaranteed visual quality thereby guaranteed the large tracts of land addressing capability.

Can bring out defective (21) or disclination in the liquid crystal material (20) with the geometric configuration of any routine.For example, known in the art, can impel the preferred alignment (isoplanar or vertical) of liquid crystal aligning selection, and periodic feature can be applied to these inside surfaces to introduce disclination with respect to the inside surface of conventional LCD.

In the embodiment of the electrophoretic display device (EPD) shown in Fig. 3 and 5, utilize dark two-dimensional array to introduce defective (21) in the liquid crystal material (20).This geometric configuration typically comprises the array of depression, and the degree of depth of each depression is d in the array, and arrangement pitches is p.In order to produce defective (21) in liquid crystal material, these depressions must be enough dark, and for this purpose, cup depth d typically is at least 1/4 to the ratio of spacing p.Usually, dark depression is impelled and form defective in liquid crystal material.

The spacing (p) 〉=1/4 [1] of the degree of depth (the d)/depression of depression

For instance, the geometric configuration that is used for electrophoretic display device (EPD) can comprise semielliptical basically, the depression hemispheric, that semicircle is spherical or half ball that is arranged in two-dimensional array.Present under the situation of oval section basically being depressed in display inside surface place, radius should be taken as the length (semiaxis is represented half of shaft length) of oval semi-major axis at this inside surface place.Can use any conventional method, method such as photoetching and embossing for example is provided for the geometric configuration of display.

The inside surface of electrophoretic display device (EPD) may require surperficial registration process, so that the preferred orientation of liquid crystal material (20) in the display is provided.In the embodiment of the electrophoretic display device (EPD) shown in Fig. 3 and 5, utilized the planar alignment of liquid crystal material (20).Electrophoresis material particle (6) in the display also can require surperficial registration process.

The amplitude dependence of the intensity of the defective (21) in the liquid crystal material (20) and corresponding potential barrier is in the profile that is used for promoting the geometric configuration of defective (21) in liquid crystal material (20).Therefore, by means of the profile that changes geometric configuration in the display, or electrophoresis material particle (6) is moved and the potential barrier that must overcome thereby also be threshold value from defective nuclear by means of changing the pre-tilt or the grappling energy of natural liquid crystal, can being trimmed in the surface of the geometric configuration that is used for promoting defective.

Note the addressing requirement of display, the threshold value that must overcome in order to remove electrophoresis material particle (6) from the first surface (24) of display can be arranged to be different from the threshold value that must overcome in order to remove electrophoresis material particle (6) from the second surface (26) of display.Therefore, asymmetry to a certain degree can be combined in for electrophoresis material particle (6) is being moved in the required current potential between first and second surfaces (24,26) of display, causes the asymmetric switching threshold of positive-negative polarity current potential.Comprise at display under the situation of a plurality of boxes or pixel (many boxes display), this asymmetry has made things convenient for multiplexed matrix addressing, and makes it possible to adopt the blank in advance technology of so-called row to come display is carried out addressing.The blank in advance technology of row makes display can be addressed (that is display can not be addressed in the half the time of time that may need if do not adopt the blank in advance technology of row) in single time slot.

Example for the standard multi multiplexing scheme known to the present technique field sees also " The ' Joers/Alvey ' Ferroelectric Multiplexing Scheme ", PWH Surguy etal, Ferroelectrics, Volume 122, pp.63-79,1991.

The described method according to manufacturing particle swimming box of the present invention of aforementioned specific embodiments comprises the following step:

Prepare the substrate that has electrode pattern on it.Photoresist is got rid of on the surface that is coated onto substrate, so that conforma layer is provided, for example, Shipley Megaposit SPR220-7 is applied to substrate, and substrate was rotated for 30 seconds with the rotating speed of 2000rpm.

According to fabrication order photoresist is handled then.Substrate typically is heated, so that separate solvent from resist.

In photoresist, form the two-dimensional array of depression then with conventional photoetching technique.As previously described, this depression can be semielliptical basically, hemisphere, semicircle sphere, or the depression of hemicycle sphere.Mask and ultraviolet source are used to photoresist is carried out graphically; For example (HEBS) greyscale photo mask (Canyon Materials company) to the high energy beam sensitivity can be used to exposure part photoresist according to qualifications.This photoresist is developed subsequently, and for example removes undesirable resist part by means of cleaning processed substrate.This just provides the surface shown in Fig. 3 and 5 to discharge shape.

Substrate is handled, so that crosslinked photoresist, thereby its solvent resistance improved.Photoresist is exposed to the deep ultraviolet radiation alternatively, is cured firmly 2 hours under 120 ℃ then, so that the sclerosis photoresist.

At last, the substrate of preparation directly is assembled in the particle swimming box, or duplicates (under latter event, can omit electrode pattern from substrate) with mold and embossed technology.

For example, the substrate of preparation can be mounted in the particle swimming box of combination of liquid crystals suspension medium and a plurality of swimming particles.These swimming particles typically were deposited to before liquid crystalline suspension medium is joined box on one of box substrate, as the part of assembly technology.

With capillary processes liquid crystalline suspension medium is combined in the particle swimming box of assembling.Perhaps use conventional vacuum fill process, thereby prevent that air is mixed in the particle swimming box.In order to reduce the division of swimming particle in the box as far as possible, lentamente liquid crystal is joined box.

Liquid crystal material typically is added into box with isotropic phase, is cooled to room temperature then apace.Formed well-known Schlieeren texture, but the release of the surface in the box impels most of defectives to be formed near the substrate of depression.Devices switch has subsequently strengthened correct liquid crystal alignment in the box.

This particle swimming box can comprise the single substrate that has releasing structure on it.Perhaps, the substrate of two preparations can be assembled into a particle swimming box, and being arranged to the depression of each in the releasing structure surface on first substrate basically in the face of the respective recesses in the releasing structure surface on second substrate, it is right that described these are recessed to form a depression.It is internal that the swimming particle is arranged on each depression of facing.

Under the situation of the substrate that does not directly use preparation, can duplicate array of depressions with mould; For example can adopt dimethyl silicone polymer (PDMS) mould.

Selected dimethyl silicone polymer (PDMS) the synthetic rubber system such as Dow Corning Sylgard 182.This is a kind of two bottle systems that prepare by means of mixing two kinds of components.

The substrate that has array of depressions on its of preparation is used as female substrate, and is covered by PDMS.This substrate is placed in the vacuum workshop, deflates, so that remove the air bubble of catching.Till this system is held PDMS and has been cured.Substrate is heated alternatively, so that accelerate the curing process.

In case be cured, just remove the PDMS mould from female substrate, and cleaning die.Typically can obtain some PDMS duplicates from female substrate by this way.This PDMS mould is used to duplicate the original two dimensional array of depression subsequently via further mold technology or embossed technology.

Various materials can be used to last mold technology.The colloid Norland 81 that a kind of such material is a UV curable.

Suitable substrate is selected, and the coated material thin-layer of waiting to want mold.Typically with 5 micron thickness wait want the material layer of mold to come coated substrates.

The substrate that applied is placed in the vacuum workshop with the PDMS mould then and system is evacuated, thereby the PDMS mould is contacted with thin layer.

Then, can from vacuum, remove mould and substrate alternatively.But the material of mold is cured then; Under the situation of Norland 81, material is exposed to ultraviolet light, solidifies so that make it.At last, remove the PDMS mould from substrate.

But heat-setting molding material can be used as the alternative of ultraviolet solidifiable material.Heat curing must be heated substrate and molding material.

In another embodiment, but the material of mold can comprise thermoplastic material.In the case, before making mould and thermoplastic material contacts, in vacuum workshop, thermoplastic material is heated.Mould is contacted with thermoplastic material, can cool off it then.In case thermoplastic material cools off, just remove mould from substrate.

Should be noted that, also can use well-known technology, make mould with the material outside the PDMS, for example nickel can be used to mould.

With reference to Fig. 7, comprise little electrophoresis system of sealing according to another embodiment of electrophoretic display device (EPD) of the present invention.This little electrophoresis system of sealing typically comprises tear drop (30) array that contains liquid crystal material (20).Each tear drop (30) sealing electrophoresis material particle (6).

As aforementioned each embodiment, electrophoresis material particle (6) is suspended in the suspension medium (7) that comprises liquid crystal material (20).But in the present embodiment, suspension medium (7) comprises the tear drop (30) that is arranged in a plurality of discrete liquid crystal material (20) in the encapsulation agent (35), is arranged with swimming particle (6) in each tear drop (30).

For example, encapsulation agent (35) can comprise any suitable adhesive, and by means of liquid crystal material tear drop (30) being distributed in this bonding agent and form little electrophoretic display device (EPD) of sealing.

In a concrete example, this is little seals liquid crystal (PDLC) display that electrophoresis system can comprise polymer dispersed, and this PDLC display has the tear drop (30) that is dispersed in the liquid crystal material (20) in the polymer substrate.

With reference to Fig. 7, select between liquid crystal (20) and inner tear drop (30) surface at the interface and the liquid crystal anchoring condition at the interface between the surface of liquid crystal (20) and swimming particle (6) by means of careful, control the position of swimming particle (6) in the tear drop (30) of liquid crystal material (20).Utilize the lip-deep non-perpendicular basically anchoring condition of tear drop (30) inside surface and swimming particle (6), shown pattern forces the generation defective in these surfaces.

The surface registration process can be used to produce favourable anchoring condition (thereby also being the favourable aligning of liquid crystal aligning) in each tear drop (30).Encouraging the tangential component of liquid crystal aligning and surface treatment inclination or isoplanar aligning is provided, is a kind of suitable surface treatment.

This surperficial registration process is impelled and form first (31) and second (32) defective in tear drop.The location of defective (31,32) in each tear drop (30) is decided by the geometric configuration of tear drop.Therefore, can customize the geometric configuration of tear drop (30), so as control defective (31,32) in tear drop the position and guarantee defective (31,32) basically in the face of be arranged in the tear drop.For example, tear drop (30) can be arranged to ball or spherical (rather than perfect spheroidal).Exactly, tear drop (30) can be customized to the chondritic that presents prolate, arranges in the face of ground basically along the major axis of prolate tear drop (30) with defective (31,32).

The generation of two defectives (31,32) in each tear drop (30) for electrophoresis material particle (6) provides the two kinds of positions that may select, thereby advanced the display with video memory.

The surface registration process can be applied to being suspended in the electrophoresis material particle (6) in each tear drop (30).The surface treatment that is used for electrophoresis material particle (6) should encourage the tangential component of liquid crystal aligning, and tilt or isoplanar aligning is provided on the surface of particle (6) once more.This surperficial registration process is used to promote lip-deep two defectives of facing (33,34) of electrophoresis material particle (6).

As shown in Figure 7, in swimming particle (6) is arranged at liquid crystal material (20) body, that is away from the defective (31 in the tear drop (30), 32) time, system then can be owing to the defective (31 in the tear drop (30), 32) and the lip-deep defective of particle (6) (33,34) and present certain Defects of Liquid energy.Intrasystem overall defect can be the intensity of defective in the system (31,32,33,34) and the function of position.

By means of current potential being applied to tear drop (30), can impel electrophoresis material particle (6) in tear drop (30), to move.

When the lip-deep defective of particle (6) (33,34) is positioned near the defective (31,32) of tear drop (30), interact between the defective.Be positioned at the defective (31 of tear drop (30) when particle (6), 32) in the time of near, intrasystem total Defects of Liquid can be lower than swimming particle (6) and be arranged in liquid crystal material (20) body, that is the total Defects of Liquid energy during away from the defective (31,32) in the tear drop (30).In the system total Defects of Liquid can this reduction, be the lip-deep defective of particle (6) (33,34) really with tear drop in defective (31,32) when close to each other so as to tending to attracted to the mechanism of the defective (31,32) in the tear drop.

Therefore, when lip-deep defective of particle (6) (33,34) and the defective (31,32) in the tear drop were superimposed, intrasystem total Defects of Liquid can be reduced to minimum.In the case, if the permission of the geometric configuration of tear drop (30) and particle (6), then the volume that occupies of defective will be 0.If the combination degree of the geometric configuration of tear drop (30) and particle (6) is less, then defective will occupy a little but non-infinitesimal volume in tear drop.In above-mentioned two kinds of arrangements, total Defects of Liquid can be reduced to minimum, and defective falls into oblivion effectively.This impels electrophoresis material particle (6) to adhere to the inside surface of tear drop (30), thereby does work for mobile from here particle (6) is just necessary.

Find that when particle (6) was positioned at the equilibrium point place of tear drop (30), the proof resilience of system can be the highest, and when particle (6) moved to any end of tear drop (30), the proof resilience of system can reduce.

Fig. 8 a-8d shows the work of this display.

Specifically with reference to Fig. 8 a, under the non-existent situation of extra electric field, a steady state (SS) is selected by system, and electrophoresis material particle (6) stop is at one end, such as place, the top of tear drop (30).When overlooking, electrophoresis material particle (6) has covered the suspension medium (7) of below, tear drop thereby present the color of electrophoresis material particle (6) basically.

Specifically with reference to Fig. 8 b, applying of the current potential that polarity is correct and amplitude is enough (40), electrophoresis material particle (6) is removed from the tear drop top, produce two defectives simultaneously, a defective (31) is positioned at the position at the original place of particle, and another defective (33) is positioned on the surface of electrophoresis material particle (6).Under the influence of externally-applied potential (40), particle (6) moves towards the bottom of tear drop (30).In case electrophoresis material particle (6) arrives the bottom of tear drop (30), the defective (32) at defective on the particle surface (34) and place, tear drop (30) bottom is just overlapping.Intrasystem total Defects of Liquid can be lower than swimming particle (6) now and be arranged in liquid crystal material (20) body, that is the total Defects of Liquid energy during away from the defective (31,32) in the tear drop (30).Overlapping defective falls into oblivion effectively.Even when current potential (40) is removed, this particle (6) still rests on the place, bottom of tear drop (30).When overlooking, suspension medium (7) has covered electrophoresis material particle (6), tear drop thereby present the color of suspension medium (7) basically.

Specifically with reference to Fig. 8 c, applying of counter potential (41) is not enough to particle (6) is pushed open from defective (32) by a small margin, particle (6) thereby be not eliminated from the zone of influence of defective (32).Therefore, after removing the field, electrophoresis material particle (6) relaxation is got back to its position in tear drop (30) bottom.

Specifically with reference to Fig. 8 d, counter potential (42) applies significantly, removed electrophoresis material particle (6), on particle (6) surface, produced a defective (34) simultaneously and produce a defective (32), and pull it the zone of influence of defective (32) at place, tear drop (30) bottom.Under the influence of externally-applied potential (42), particle (6) turns back to its origin-location at place, tear drop (30) top.In case particle (6) arrives tear drop (30) top, two defectives (31,33) are just overlapping.Intrasystem total Defects of Liquid can be lower than swimming particle (6) once more and be arranged in liquid crystal material (20) body, that is the total Defects of Liquid energy during away from the defective (31,32) in the tear drop (30).Overlapping defective falls into oblivion effectively, and particle (6) rests on this position.

In each embodiment shown in Fig. 7 and 8, to the surperficial registration process that electrophoresis material particle (6) carries out, guaranteed on particle in liquid crystal material (6) surface to produce defective (33,34), and the size of tube particle (6) is not how.Therefore, electrophoresis material particle (6) can be arranged to optimum dimension, so that increase light scattering as far as possible, thereby provides the display of hard contrast.

In practice, electrophoresis material particle (6) is selected as enough big, and high light diffusion is provided when being positioned at place, tear drop (30) top with box lunch.Particle (6) also should be enough big, hides the suspension medium of below when being positioned at tear drop (30) top with box lunch basically, pointed out by Fig. 8 a and 8d.When electrophoresis material particle (6) is positioned at the tear drop bottom (seeing Fig. 8 b and 8c), suspension medium (7) must be able to cover swimming particle (6), and this may influence the size of the electrophoresis material particle of selecting for display (6).

Usually, the radius of swimming particle (6) can be arranged to be at least 30% of tear drop (30) radius, so that rationally hiding of suspension medium (7) is provided.The radius of swimming particle (6) typically is rendered as about 50% of tear drop (30) radius.Under tear drop (30) is spherical situation, measure radius along the axle of its arrangement perpendicular to defective (31,32).For example, be under the situation that prolate is spherical and defective (31,32) is arranged over the ground along the macropinacoid of prolate tear drop (30) basically at tear drop (30), the minor axis that then will cross over tear drop (30) is measured the radius of tear drop (30).

The yardstick of electrophoresis material particle (6) may to liquid crystal (20) in display in to form the relevant energy barrier of defective influential.Therefore, the size of swimming particle (6) may influence the potential energy potential barrier, thereby influences the current potential threshold value in the display.Remember top situation, can select particle size according to the finishing of display inner potential threshold value.

In practice, the radius of electrophoresis material particle (6) can be positioned at abiogenous distribution, and this makes that little display device of sealing according to the present invention can show a series of gray shade scales (gray scale).For example, each pixel in the display can comprise a plurality of tear drops (30).As mentioned above, the radius distribution of interior each particle (6) of tear drop (30) will cause the corresponding distribution of the current potential threshold value relevant with each tear drop (30).Therefore, the amplitude that is applied to the current potential of each pixel in the display will determine to change in this pixel the number of the tear drop (30) of optical states.In this example, the optical states of the number of tear drop and each pixel is relevant in the reflectivity of each pixel and the pixel.Therefore, the reflectivity of pixel will be proportional to the amplitude of (decision wherein changes the tear drop number of the optical states) current potential that is applied to this pixel, thereby make each pixel can show a series of gray shade scales.

Though each embodiment of the present invention shown in Fig. 7 and 8 provides the display of the video memory with non-linear electric light behavior, but combination asymmetry to a certain degree in the desired current potential of electrophoresis material particle (6) in mobile tear drop (30), the asymmetric switching threshold that causes positive negative potential may be useful for the addressing purpose.As mentioned above, this asymmetry has made things convenient for the multiplexed matrix addressing of many boxes display, and makes the blank in advance technology of so-called row can be used to display is carried out addressing.

For the purpose of clear, the foregoing description of each embodiment of the present invention had not been mentioned the concrete material that uses in the display.

The many liquid crystal materials and relevant dyestuff that use in the conventional LCD can successfully apply in each embodiment of the present invention described herein.Also can use oil-soluble dyestuff of any kind.

The scope of suitable liquid crystal material comprises nematic liquid crystal, and for example any Merck liquid crystal compound of enumerating of table 1.0 can be used to the present invention.

Merck The potpourri sign indicating number	?Merck The potpourri sign indicating number	?Merck The potpourri sign indicating number
			ZLI-4792	?MLC-6849-000	?MLC-9400-000
ZLI-5080	?MLC-6849-100	?MLC-9400-100
			ZLI-5091	?MLC-6873-000	?MLC-12000-000
MLC-6043-000	?MLC-6873-100	?MLC-12000-100
			MLC-6043-100	?MLC-6874-000	?MLC-12100-000
MLC-6219-000	?MLC-6874-100	?MLC-12100-100
			MLC-6219-100	?MLC-6875-000	?MLC-13200-000
MLC-6222	?MLC-6875-100	?MLC-13200-100
			MLC-6241-000	?MLC-6876-000	?MLC-13300-000
MLC-6241-100	?MLC-6876-100	?MLC-13300-100
			MLC-6252	?MLC-6893-000	?MLC-13800-000
MLC-6256	?MLC-6893-100	?MLC-13800-100
			MLC-6292-000	?MLC-7700-000	?MLC-13900-000
MLC-6292-100	?MLC-7700-100	?MLC-13900-100
			MLC-6625	?MLC-7800-000	?MLC-6601
MLC-6628	?MLC-7800-100	?MLC-6614
			MLC-6694-000	?MLC-9000-000	?MLC-6686
MLC-6694-100	?MLC-9000-100	?MLC-6692
			MLC-6846-000	?MLC-9100-000	?MLC-15900-000
MLC-6846-100	?MLC-9100-100	?MLC-15900-100
			MLC-6847-000	?MLC-9200-000	?MLC-16000-000
MLC-6847-100	?MLC-9200-100	?MLC-16000-100
			MLC-6848-000	?MLC-9300-000
MLC-6848-100	?MLC-9300-100

Table 1.0

Can select liquid crystal material according to the desired Performance Characteristics of display.For example, the slewing rate of display relates to the viscosity of suspension medium (7), and therefore, for requiring the application of slewing rate fast, the liquid crystal material that viscosity is low may be preferred.

Being combined in dyestuff in the suspension medium (7) can comprise and be applicable to the guest-host effect display system and [see " Dyes inLiquid Crystals ", Molecular Crystals with the compatible any conventional dyestuff of the liquid crystal material that is used for display (20); Liquid Crystals, Vol.150A, A.V.Ivashchenko, V.G.Rumyantsev].Suitable dyestuff comprises azo dyes and anthraquinone dye.Also can adopt oil-soluble food dye, medicine dyestuff and cosmetic dyes.

Equally, the many materials that are used for conventional electrophoretic display device (EPD) can successfully work in each embodiment of the present invention described herein.

For example, titania is normally used for the electrophoresis material particle in the conventional electrophoretic display device (EPD), and can be used as the electrophoresis material (6) in the embodiment of the present invention.The reason why titania can be normally used for the electrophoresis material particle is that it presents good optical reflectivity and scattering nature.As an alternative, depend on the performance index of display, other material, for example Ran Se material also can be used to electrophoresis material particle (6).Exactly, the electrophoresis material particle can comprise the ball with reflective surface will, for example has the little polymkeric substance ball that is coated with reflective metal or dielectric surface coating on it.Under the situation of dielectric coated, coating can comprise reflectivity multilayered medium lamination.

As mentioned above, surface treatment can be applied to aligning according to qualifications and the control particle charge that electrophoresis material particle (6) impels particle surface place liquid crystal material (20).The conventional surface treatment that the skilled person knows can be applied to electrophoresis material particle (6) and obtain specific effect.The surface coating that electrophoresis material particle (6) typically can have silicon dioxide with and go up the organic coating of coating so that reduce flocculation and give surperficial alignment property.Utilize another example, can in mercaptan, apply particle, so that control electric charge and aligning with the technology of knowing with argent coating with suitable end group.Equally, can in silane, come coating tool that the particle of oxide skin(coating) is arranged.

With reference to Fig. 9, electrophoresis material particle (6) can comprise composite particles, so that increase light scattering as far as possible, thereby provides good reflectivity.In structure shown in Figure 9, electrophoresis material particle (6) comprises the scattering particles (45) that are arranged in the bonding agent (46).The reflectivity that this arrangement has strengthened can be the repeatedly scattering between adjacent scattering particles and the below scattering particles (45) in the composite particles by attribution.Therefore, be incident on most of light (47) on the particle before returning, in composite particles, be scattered from particle (48) scattering.

Scattering particles (45) can comprise the electrophoresis material of any routine, for example titania.As an alternative, scattering particles (45) can comprise the polymer globules that combination has whitening agent, and suitable whitening agent comprises gas cavity (for example air bag) and scrap hard rock.The material of bonding agent (46) any substantial transparent that refractive index is different with scattering particles (45) typically.This bonding agent (46) can be crosslinked polymkeric substance, for example polymethylmethacrylate (PMMA).

The particle dispersion of titania can be made above-mentioned compound swimming particle (6) in monomer system.Then, utilize the emulsification in the water that is mixed with suitable surfactant therein to form the monomer tear drop, and become spheroidal by surface tension effects.This monomer tear drop is cured subsequently.Carefully select monomer and surfactant, make it possible to control the liquid crystal anchoring condition of compound swimming particle (6) surface.After solidifying,, must remove surfactant up hill and dale from particle (6) usually with any further first being processed.Final swimming particle (6) can be intrinsic hydrophobic, or can be processed to provide hydrophobic surface subsequently, and this is combined in the electrophoretic display device (EPD) described herein subsequently for composite particles (6) is favourable.

As the accommodation of removing surfactant from compound swimming particle (6), if the combination of employing such as polyvinyl alcohol (PVA) (PVA) has the polymer surfaces activator of hydroxyl functional group (OH), then can't can be used as the basis of the compound swimming particle of further coating (6) usually from the polymer residue layer that particle surface rinses out.The OH functional group can be used to the Different Silicon hydride compounds of any number is fixed to the surface of polymer beads.By means of suitably selecting silane, can change the processing characteristics of particle.Equally, by means of suitably selecting silane compound, can regulate liquid crystal anchoring condition on the particle surface and the electrophoresis electric charge on the particle.

The yardstick of electrophoresis material particle (6) and display in making the performance index of used material and display relevant.In conventional electrophoretic display device (EPD), in order to obtain big as far as possible light scattering, the size of electrophoresis material particle (6) is roughly the same with the light wavelength that is incident on the display.

Under the situation of compound swimming particle, in order to obtain big as far as possible light scattering, the size of scattering particles (45) should be roughly the same with the light wavelength that is incident on the display.In addition, scattering particles (45) should be dispersed in each compound swimming particle well, and between the refractive index of the refractive index of scattering particles (45) and bonding agent (46) big difference should be arranged.

For particle with reflective coating, the size of particle typically at least 10 times greater than the light wavelength that is incident on the display.

In practice, the size of swimming particle (6), or under the situation of compound swimming particle, the size of scattering particles (45) is not crucial for the optical property of device, as long as guarantee enough backward scatterings.

Equally, little yardstick of sealing tear drop in the electrophoretic display device (EPD) system (30) of the present invention is also relevant with the performance index of material used during display is made and display.

For little electrophoretic display device (EPD) system that seals of the present invention shown in Fig. 7 and 8, the length of tear drop (30) can be the 1-30 micron, and typical length is the 5-20 micron.For specific application, the length of tear drop (30) can be chosen as the 10-15 micron.Under tear drop (30) is spherical situation, should be parallel to defective (31,32) is measured tear drop along the axle of its arrangement length.For example, be under the situation that prolate is spherical and defective (31,32) is arranged over the ground along the macropinacoid of prolate tear drop (30) basically at tear drop (30), then should measure the length of tear drop (30) along the major axis of tear drop (30).

Be suspended in equally the diameter of the electrophoresis material particle (6) in the tear drop (30) can 0.2-0.8 doubly to the diameter of tear drop.The diameter of electrophoresis material particle (6) typically is 0.3-0.7 doubly to the diameter of tear drop.For specific application, the diameter of swimming particle (6) is that 0.4-0.6 is doubly to the diameter of tear drop (30).Under tear drop (30) is spherical situation, should measure the diameter of tear drop (30) along the axle of its arrangement perpendicular to defective (31,32).For example, be that then the diameter of tear drop (30) should be taken as the diameter of the minor axis of tear drop (30) under the situation that prolate is spherical and defective (31,32) is arranged over the ground along the macropinacoid of prolate tear drop (30) basically at tear drop (30).

As (see figure 1) in the conventional prior art, can comprise suspension medium (7) and be clipped in transparent insulation substrate (3a, 3b) the electrophoresis material particle (6) between according to each embodiment of display of the present invention.Substrate can be rigidity or flexible, for example polymer film.Under little situation of sealing electrophoresis system (seeing Fig. 7 and 8), encapsulation agent (35) can provide machinery support for suspending medium matter and the electrophoresis material particle (6) that is suspended in wherein.In the case, can omit one or two substrates (3a, 3b).

For example, little sealing in the electrophoretic display device (EPD) according to the present invention, can arrange encapsulation agent (35) to come to provide all basically machinery supports for the tear drop (30) that comprises liquid crystal material (20) and electrophoresis material particle (6).

In described herein each embodiment of the present invention, utilize externally-applied potential to impel electrophoresis material particle (6) in display, to move.The device that applies current potential can be that (4a 4b), comprises the electrode that is positioned at lip-deep at least one substantial transparent of device to conventional electrode, so that display can be observed.Therefore, Chang Gui tin indium oxide (ITO) electrode can be used to each embodiment of the present invention.

As an alternative, the polymer electrode of conduction can be used for current potential is applied to device.The electrostrictive polymer ultimate ratio ITO electrode of conduction is firmer, and can bear under the situation of mechanical bend power at display or in the application under the situation of imagination flexible display, may be preferred.

In another embodiment of the present invention, can current potential be applied to display via the electrode of device outside.The desired electric field strength representative of device work ground should be in the scope of every micron 1-10V.And current potential can comprise the electric field that is applied to device via removable electrode from the outside.In this specific structure, display can be worked as the display device that is used for writing down permanent image basically.

About each embodiment of the present invention shown in Fig. 7 and 8, can make little electrophoretic display device (EPD) of sealing with following technology.

Little first step of sealing in the electrophoretic display device (EPD) manufacturing is that preparation is used for being combined to the electrophoresis material particle (6) in the tear drop (30).As mentioned above, little electrophoretic display device (EPD) of sealing can make up compound swimming particle (6) (see figure 9), and these particles can be prepared as follows.

With reference to Figure 10 a, suitably the titania selected (50) of grade becomes to have the particle size of the light scattering character that provides good, and preferably has the surface of coated with silica.This titania is processed, so that give particle (6) with hydrophobicity.For example, can adopt conventional silanization technology.Disperse (51) in the anhydrous cyclohexane of 400ml by means of titania, then alkyl trichlorosilane (being the octyl group trichlorosilane of 0.2g in the case) is added (52) to suspending liquid, accomplished this point 20g.Emulsification (53) 4 hours is dispersed in the system and octyl group trichlorosilane and titanium dioxide surface complete reaction so that guarantee titania fully.Titanium dioxide granule separates (54) from cyclohexane in hydro-extractor, mix (55) with fresh cyclohexane then.This technology is repeated secondary, and titania was dried in 80 ℃ stove (57) 1 hours.Titanium dioxide granule is exactly hydrophobic (58) now.

Next step during compound swimming particle (6) is made is, under the situation that has crosslinking chemical and initiating agent (for example thermal initiator or light trigger), with optical scatter (45), is titania in the case, disperses (60) in non-water-soluble monomer.This potpourri is by the suitably aqueous solution emulsification (61) of surfactant, so that produce the monomer tear drop that wherein is dispersed with scattering particles.Initiating agent is activated (62), so that promote the crosslinked of monomer.Under the situation of thermal initiator, this activation can be heating, and under the situation of light trigger, this activation can be to shine with electromagnetic radiation.

With reference to Figure 10 b, 20g's is that hydrophobic titania is disperseed (60) in the potpourri of 49g methyl methacrylate, 29g neopentyl glycol dimethylacrylate and 2g thermal initiator lauroyl peroxide now.This potpourri is emulsified (61) in 1% solution of polyvinyl alcohol (PVA), and molecular weight is 125000.The quantity of the vigor of this emulsifying step and/or polyvinyl alcohol (PVA) adjuvant can be used to control the size of particle.Then this emulsion is placed (62) 80 ℃ preheating stove 1.5 hours.When stove shifts out, product is by centrifugal (63), and excessive moisture is eliminated, and mixes (64) particle again with fresh water then.This technology is repeated several times.

Can further handle these compound swimming particles (6), with convenient follow-up processing be controlled at liquid crystal alignment on the particle.Following technology (65) makes it possible to the silane such as phenyl trichlorosilane is added to surface on the compound swimming particle, so that can control follow-up processing and the liquid crystal alignment on particle.These compound swimming particles are located away from water, and replace water with dry tetrahydrofuran (THF), repeat to wash several times and separate with THF.Replace THF with dry cyclohexane then, and repeat to wash several times and separate.Composite particles (6) is in the anhydrous relatively environment then, so the particle of separation can be added in the potpourri of silane in cyclohexane.In mixed process, this composite particles was stayed in this potpourri about 1 hour.Separate composite particles from cyclohexane with silane mixture then, and in the cyclohexane of drying, wash several times as mentioned above, so that remove residual silane.At last, these compound swimming particles are dried (67) in warm electric furnace, so that produce free-pouring powder.

Next stage relates to and is distributed to swimming particle (6) in the liquid crystal tear drop (30) and the sealing of tear drop (30), so that form the free-pouring powder that comprises the drying of separating the tear drop of sealing (30).Can adopt conventional titania swimming particle (6) or compound swimming particle (6).

With reference to Figure 11, traditional wrapper technology relates to and uses gel and gum arabic, and relates to the powerful emulsification of liquid crystal in gel solution.Hydrophobic swimming particle (6) is mixed with liquid crystal (20), and this potpourri emulsified in gel solution (72).(73) are further mixed by this system with gum arabic solution, and continue encapsulating process by means of water dilutes (76) lentamente.This causes that cohesion (colloid polymerization) layer is deposited on tear drop (30) on every side.At this moment, glutaraldehyde solution is added into (78) to system, so that crosslinked each protein chain, and system is cooled (79), so that when cross-linking process carries out, makes gel form colloid.The capsule and pill (85) of these curing that comprises liquid crystal (20) and swimming particle (6) is then by spray drying (80), so that produce dry free-pouring powder.

Can be by means of the agglomeration step of an accommodation being included and revising this wrapper technology.With reference to Figure 12, liquid crystal (20) and swimming particle (6) emulsified in gel solution (72).(73) are further mixed by this system with gum arabic solution.In this embodiment of the present invention, the pH value (77) by means of the pH value (75) that improves emulsion, dilute with water (76) and reduction emulsion continues encapsulating process.This makes cohesion (colloid polymerization) layer be deposited on tear drop (30) on every side.At this moment, glutaraldehyde solution is added into (78) to system, so that the cross-linked proteins chain, and system is cooled (79), so that when cross-linking process carries out, makes gel form colloid.The capsule and pill (85) of these curing that comprises liquid crystal (20) and swimming particle (6) is then by spray drying (80), so that produce dry free-pouring powder.

Wrapper technology is based on traditional gel and gum arabic encapsulating process.Specifically, the high blank intensity of 1g gel (isoelectric point pH8) is dissolved in the water of 25ml under 50 ℃.Simultaneously, the 1g gum arabic is dissolved in the water of 50ml under 50 ℃ and puts aside.Simultaneously, the (see figure 10) 10g that produces as previous is dispersed in the titanium dioxide granule of the drying in the polymethylmethacrylate, be distributed to up hill and dale in the commercially available liquid crystal that 20g selects (for example table 1.0 enumerate any Merck liquid crystal), oil-soluble (non-water-soluble) of wherein having dissolved 2% weight ratio is such as 1-hydroxyl-4-[(4-toluene) amino]-9, the dichroic dye of 10-amerantrone and so on.This potpourri of particle (6) and liquid crystal (20) is joined in the gel solution of 25ml lentamente, and continues to mix.Sodium hydroxide solution is added into the emulsion that obtains, so that the pH value is brought up to 12.Then with gum arabic solution emulsion mixing therewith.Again this emulsion is transferred to bigger beaker, and, continue simultaneously to mix lentamente as in all previous steps, being maintained at 50 ℃.Under 50 ℃, the water of 200ml joined system then and stir, until mixing up hill and dale.At this moment, 10% acetic acid solution is dropwise splashed into emulsion, reaches 4.7 until the pH value, and this has started cohesion and protein layer in tear drop (30) formation on every side.0.35g 50% glutaraldehyde solution be added into emulsion so that crosslinked each capsule and pill wall is reduced to 10 ℃ with temperature then in half an hour.So the pH value of emulsion brings up to 11.Shelve this emulsion then, make it to mix at least 12 hours, and the temperature of system is lifted to room temperature.With standard techniques to the sclerosis that obtains capsule and pill (85) carry out drying, produce free-pouring powder.

Above technical description the gel and the gum arabic wrapper technology of tear drop (30) of liquid crystal material (20).In the document that table 2.0 is enumerated, further described the selection of suitable wrapper technology.

Document	Describe
		Patent No.US2800457	Green BK and Schleicher L; July nineteen fifty-seven: be applicable to each embodiment described herein
Patent No.US3041288	Anthony WH; In June, 1962; Fractionation gel-gum arabic cohesion with the high molecular of pH regulator can provide the capsule and pill loss less firmer capsule and pill by means of being clamped together.
		ISBN0815504497	" capsule and pill technology and little seal 1972 " M Gutcho, Noyes Data Corporation, New Jersey, USA, 1972, ISBN 0815504497

Table 2.0

But can adopt any suitable wrapper technology to make little electrophoretic display device (EPD) of sealing of the present invention.

Little final step of sealing in the electrophoretic display device (EPD) manufacturing is, the capsule and pill (85) that has hardened is combined in the body encapsulation agent (35), so that form display device.

With reference to Figure 13, the powder of sclerosis capsule and pill (85) is disperseed (90) to presenting in the body encapsulation agent (35) of little contraction when solidifying.Encapsulation agent (35) can comprise high density capsule and pill (85) is provided but low viscosity and the bonding agent of ultraviolet (UV) or heat curing.Notice that capsule and pill this moment (85) can be ball or ball, for example the ball of prolate.

Then, this dispersion is placed in (91) combination has between two substrates of electrode pattern.Electric field or magnetic field are applied to (92) this system, so that aim at capsule and pill (85) rightly.For example, under the liquid crystal (20) in capsule and pill (85) is prolate ball and capsule and pill (85) and the situation that the major axis of prolate capsule and pill (85) is aimed at, then capsule and pill (85) should be aimed at the major axis perpendicular to substrate.Body encapsulation agent (35) is cured (93), thereby the capsule and pill that will aim at is fixed in the encapsulation agent (35).

Specifically, dispersion is applied on the electrode position substrate such as glass thereon of tin indium oxide and so on.This electrode can be a metal also, so that the reflective surface will of conduction is provided by graphically.Coating is the degree of depth of 1-2 capsule and pill (85) typically, and one of them capsule and pill (85) typically is about 10 microns.This layer upper quilt layer folded another substrate, is transparency electrode on it, and this transparency electrode also can be patterned to the matrix array that produces pixel with other electrode pattern.Then, aim at the orientation of capsule and pill (85) by means of between substrate, applying electric field.Perhaps, can finish this point with magnetic field.After aiming at, solidify (93) encapsulation agent (35) by means of ultraviolet exposure.

As an alternative, aiming at the step of (92) capsule and pill (85) and the step of curing (93) body encapsulation agent (35) can exchange.In this embodiment, can adopt the low contraction elasticity encapsulation agent (35) of heat curing, silicone synthetic rubber system for example is as Dow CorningSylgard 182.In the case, adopt the big substrate of expansion coefficient.The contraction of substrate after solidifying causes encapsulation agent (35) pressurized in substrate plane.This forces the capsule and pill (85) in the encapsulation agent (35) to become the prolate sphere of major axis perpendicular to substrate.The interior liquid crystal (20) of each capsule and pill that is in what is called " boojum " structure owing to normal flat surfaces anchoring condition is aimed at the major axis of prolate capsule and pill (85) subsequently.In this embodiment of the present invention, the thermal expansivity of substrate must be chosen to the thermal expansivity greater than encapsulation agent (35).In use, encapsulation agent (35) must remain in substrate plane under the compressive state, keeps the sphere of prolate so that guarantee capsule and pill (85).

The other method that reaches above-mentioned effect is to adopt solidifying the resilient substrate that encapsulation agent (35) can be upheld before.In this embodiment of the present invention, solidifying encapsulation agent (35) before, substrate is upheld.Substrate after being cured, can be shunk encapsulation agent (35).As previous, the contraction of substrate after solidifying causes encapsulation agent (35) pressurized in substrate plane.This forces the capsule and pill (85) in the encapsulation agent (35) to become the prolate sphere of major axis perpendicular to substrate.As previous, silicone synthetic rubber system, for example Dow CorningSylgard 182 can be used in this embodiment of the present invention.Encapsulation agent (35) also must remain in substrate plane under the compressive state, keeps the sphere of prolate so that guarantee capsule and pill (85).

The another kind of technology that constitutes capsule and pill (85) is after the body encapsulation agent has cured, the character of dispersion to be revised.In this embodiment of the present invention, dispersion is applied on the substrate, and solidifies body encapsulation agent (35), thereby capsule and pill (85) is fixed and and substrate bonding.Notice that capsule and pill this moment (85) can be the ball of ball or random orientation.In solidification process, the body encapsulation agent might shrink, and this may force the capsule and pill (85) in the encapsulation agent (35) to become the prolate sphere that major axis is parallel to substrate.But this not preferred structure of capsule and pill process segment in the middle of this is unessential.After solidifying, for example by means of diffusion, suitable material is introduced in the body encapsulation agent (35), so that encapsulation agent (35) is expanded.Because encapsulation agent (35) has been bonded to substrate in solidification process, so encapsulation agent (35) only can expand along the direction that is substantially perpendicular to substrate plane.Therefore, the expansion of encapsulation agent (35) forces capsule and pill (85) to become the prolate sphere of major axis perpendicular to substrate.

As previously described, can adopt the low contraction elasticity encapsulation agent (35) of heat curing, silicone synthetic rubber system for example is as Dow Corning Sylgard 182.Under the elastomeric situation of silicone, silicone oil can be diffused in the synthetic rubber, and synthetic rubber is expanded.In practice, silicone oil being diffused into step in the silicone synthetic rubber of curing comprises synthetic rubber is immersed in the silicone oil.Good diffusion in the silicone synthetic rubber that the silicone oil that molar mass is low can be used to guarantee to solidify.

With reference to Figure 14, show little local constructed profile of sealing electrophoretic display device (EPD) (100) of a kind of situation according to the present invention.This little electrophoretic display device (EPD) (100) of sealing comprises a plurality of liquid crystal tear drops (30), and each tear drop has a swimming particle that is arranged in wherein.Utilize encapsulation agent (35), tear drop (30) be encapsulated in two substantially parallel substrates (101a, 101b) between.In special construction shown in Figure 14, tear drop (30) presents the prolate spherical structure, the major axis of tear drop (30) be arranged in be substantially normal to substrate (101a, 101b).This is little seals electrophoretic display device (EPD) (100) and also comprises and be arranged in substrate (101a, 101b) a plurality of band electrodes (102,103) on the inside surface.In use, each electrode is used to electric field is applied to interior each tear drop (30) of display (100).

In embodiment of the present invention shown in Figure 14, electrode (102,103) is aligned to row and column in display (100).Specifically, the electrode (102) of contiguous first substrate (101a) is arranged embarks on journey, and the electrode (103) of contiguous second substrate is aligned to row.Column electrode (102) and row electrode (103) typically are aligned to basically and are perpendicular to one another.

Electrode becomes this matrix that a kind of addressable image component (pixel) is provided in the display (100) that is arranged in of ranks.Each pixel is made up of the column electrode (102) and the intersection point of row electrode (103).Each pixel comprises at least one the liquid crystal tear drop (30) that wherein is arranged with a swimming particle (6).Swimming particle (6) in the tear drop (30) can be applied in the control of Electric potentials between corresponding column electrode of this pixel and the row electrode.Therefore, made things convenient for the matrix addressing of the interior pixel of display (100).In practice, each pixel can comprise a plurality of this tear drops (30), thereby makes each pixel can show a series of gray shade scale (gray scale).In order to see tear drop (the 30)/swimming particle (6) of below, at least one electrode (102,103) can be transparent.

Should be noted that liquid crystal tear drop (30) shown in Figure 14 can comprise the capsule and pill (85) that is dispersed in the encapsulation agent (35).And little electrophoretic display device (EPD) (100) of sealing can be configured to substrate (101a, the layer between 101b) be the degree of depth (for the purpose of clear, the degree of depth of single capsule and pill being shown among Figure 14) of or two capsule and pills (85) typically.

Though in above-mentioned device, comprised electrode, above-mentioned littlely sealed the current potential that electrophoretic display device (EPD) can utilize electrode via the device outside to be applied to display and come work.And this current potential can comprise the electrostatic field that applies from the device outside via removable electrode.

For the purpose of clear, should be noted that, in Figure 14, be illustrated as changing fully by each particle swimming box (those of display (100) left side) of first electrode (103) addressing, and be illustrated as partly changing by adjacent each particle swimming box of second electrode (103) addressing.By this way, can in display (100), obtain a series of gray shade scales.

About the type of the dyestuff that is used for each embodiment of the present invention, usually, all dyestuffs that dissolve in the liquid crystal all can be used in each embodiment of the present invention described herein.And any combination of these dyestuffs can be used to produce required color in device.Black for example.

Table 3.0 has confirmed to be applicable to the selection of the dyestuff of each embodiment of the present invention described herein.

The CI title	The FDA title	Chemical name
			Solvent violet 13	D ﹠ C purple 2	1-hydroxyl-4-[(4-aminomethyl phenyl) amino]-9, the 10-amerantrone
Solvent yellow 33	D ﹠ C red 17	2-(2-quinolyl)-1,3-indenes diketone
			Solvent green 3	Green 6 K7016 of D ﹠ C	1, two [(4-aminomethyl phenyl) amino]-9 of 4-, 10-amerantrone
Solvent red 23	Yellow 11 K7064 of D ﹠ C	1-[[4-(phenylazo) phenyl] azo]-2 naphthalene enols

Table 3.0

Main above-mentioned each embodiment of with regard to electrophoresis behavior, having described according to particle swimming display device of the present invention.But as emphasizing previously, the magnetophoresis behavior can be applicable to each embodiment described herein equally.The magnetophoresis operation can be used as a kind of of electrophoresis operation really and substitute in above-mentioned each embodiment.As an alternative, magnetophoresis operation and electrophoresis operation can be combined and be used for changing the show state of device described herein.

For the magnetophoresis behavior being combined in above-mentioned any one embodiment, only require to adopt to have magnetic or ferromagnetic swimming particle.This swimming particle can be to respond externally-applied magnetic field similar in appearance to aforementioned mode to electric field.For example, in magnetophoretic display according to the present invention, be applied to display by means of the magnetic field with given field intensity, show state can be changed.Can provide this magnetic field with permanent magnet (pen or the form of contact pilotage that for example have magnet), maybe can produce this magnetic field with electromagnet with the tip.As before, under the influence of impressed field (though being such electric field in magnetic field rather than front or electrostatic field), the swimming particle can move in device.

Aforesaid threshold effect from the disclination in the liquid crystal material (20) can be with similar in appearance to previously the described mode of particle swimming box being operated in the magnetophoresis box.Therefore, the various advantages from described threshold effect described herein can be awarded magnetophoretic display in the mode that is same as electrophoretic display device (EPD).

Present the two mixed display device of electrophoresis and magnetophoresis behavior further conversion combination is provided.For example, be used to have the pen of magnet or the localization magnetic field of contact pilotage from the tip, this combining display can be by space conversion.But this display can utilize whole display is applied current potential and is wiped free of, and this may be transformed into the swimming particle a kind of state such in the pure electrophoretic display device (EPD).And, by means of surveying the little pulse current that brings out by the conversion of device between show state, can write down the information that writes on this display.By means of the electrode of composite figureization in this display and the delegation of wiping image simultaneously, can finish this dark survey.

Claims (57)

1. particle swimming box, it comprises the liquid crystal cell that wherein has liquid crystal material and swimming particle, and this swimming particle can move to second side of liquid crystal cell from first optimum position of liquid crystal cell first side when applied field,

This liquid crystal cell is selected to when the swimming particle is not positioned at the first optimum position place; exist a kind of defective relevant with first optimum position; and when the swimming particle is located substantially on the first optimum position place in the liquid crystal cell, lower when the Defects of Liquid energy of described defective is not located like this than swimming particle.

2. according to the particle swimming box of claim 1, wherein, for the swimming particle is moved to second side of liquid crystal cell from first optimum position, impressed field must surpass threshold level.

3. according to the particle swimming box of claim 1 or 2, wherein, the swimming particle can reverse second optimum position from liquid crystal cell second side when applied field moves to first optimum position at the liquid crystal cell first side place,

This liquid crystal cell is adapted to when the swimming particle is not positioned at second optimum position; exist the defective relevant with second optimum position; and when the swimming particle was located substantially in the liquid crystal cell the second optimum position place, the Defects of Liquid energy of described defective was lower than the energy when the swimming particle is not located like this.

4. according to the particle swimming box of claim 3, wherein, for the swimming particle is moved to first optimum position in the liquid crystal cell from second optimum position, impressed field must surpass threshold level.

5. according to the particle swimming box of claim 4, wherein, move to the amplitude of the relevant threshold level of second optimum position with the swimming particle from first optimum position in the liquid crystal cell, be different from the swimming particle moves to the threshold level of first optimum position from second optimum position in the liquid crystal cell amplitude.

6. according to any one particle swimming box among the claim 1-5, it has a plurality of first optimum positions at the liquid crystal cell first side place, and each first optimum position has associated defective, and a plurality of swimming particle dispersion is in liquid crystal material.

7. according to the particle swimming box of claim 6 dependent claims 3, it has a plurality of second optimum positions at the liquid crystal cell second side place, and each second optimum position has associated defective.

8. according to the particle swimming box of claim 6 or 7, wherein, at least one inside surface of liquid crystal cell is shaped to and brings out described defective.

9. particle swimming box according to Claim 8, wherein, this shaping comprises a plurality of depressions that are arranged in array.

10. according to the particle swimming box of claim 9, wherein, these depressions are aligned to regular array.

11. according to the particle swimming box of claim 10, wherein, this array comprises a two-dimensional array, and each is recessed in and wherein is aligned to the solid matter structure.

12. according to the particle swimming box of claim 11, wherein, each is recessed in and is arranged to six side's solid matter structures in the array.

13. according to any one particle swimming box among the claim 9-12, wherein, depression comprises the depression of semielliptical basically.

14. according to the particle swimming box of claim 13, wherein, depression comprises hemispheric basically depression.

15. according to the particle swimming box of claim 14, wherein, depression comprises the depression of semicircle sphere basically.

16. according to the particle swimming box of claim 15, wherein, depression comprises the depression of half ball basically.

17. according to any one particle swimming box among the claim 9-16, wherein, each is recessed in and is aligned to spacing in the array is p, and the degree of depth of each depression is d.

18. according to the particle swimming box of claim 17, wherein, the depth d of these depressions is at least 1/4 to the ratio of spacing p.

19. according to any one particle swimming box among the claim 3-5, wherein, liquid crystal cell comprises the liquid crystal tear drop.

20. according to the particle swimming box of claim 19, wherein, particle swimming box comprises a plurality of liquid crystal cells.

21. according to the particle swimming box of claim 20, wherein, the liquid crystal tear drop is spheroidal basically, the length L of each liquid crystal tear drop equals the diameter D of tear drop.

22. particle swimming box according to claim 20, wherein, the liquid crystal tear drop is the ball of prolate basically, and each liquid crystal tear drop is L along the length of liquid crystal tear drop major axis, diameter along minor axis is D, and first and second optimum positions are arranged on the contrary along the major axis of each liquid crystal tear drop basically.

23. according to any one particle swimming box in each claim of front, wherein, liquid crystal cell or each liquid crystal cell comprise dyestuff.

24. according to any one particle swimming box in each claim of front, wherein, liquid crystal cell or each liquid crystal cell comprise oil-soluble dyestuff.

25. particle swimming box according to claim 23 or 24, wherein, it is one of following at least that dyestuff comprises: dichroic dye, azo dyes, anthraquinone dye, the medicine dyestuff, cosmetic dyes, food dye, 1-hydroxyl-4-[(4-aminomethyl phenyl) amino]-9, the 10-amerantrone, 2-(2-quinolyl)-1,3-indenes diketone, 1, two [(4-aminomethyl phenyl) amino]-9 of 4-, the 10-amerantrone, 1-[[4-(phenylazo) phenyl] azo]-2 naphthalene enols, solvent black 3, solvent black 5, solvent black 7, solvent black 12, solvent black 28, solvent blue 4, solvent blue 19 4, solvent blue 19, solvent blue 29, solvent blue 35, solvent blue 36, solvent blue 37, solvent blue 38, solvent blue 43, solvent blue 59, solvent blue 78, solvent blue 97, solvent blue 19 04, solvent brown 1, solvent brown 53, solvent green 1, solvent green 3, solvent green 4, solvent green 5, solvent green 7, solvent green 11, solvent green 28, solvent orange 1, solvent orange 2, solvent orange 7, solvent orange 15, solvent orange 20, solvent orange 23, solvent orange 60, solvent orange 63, solvent orange 105, solvent red 3, solvent red 19, solvent red 23, solvent red 24, solvent red 26, solvent red 27, solvent red 41, solvent red 43, solvent red 44, solvent red 45, solvent red 49, solvent red 72, solvent red 111, solvent of red 135, solvent red 140, solvent red 179, solvent red 195, solvent red 207, solvent purple 8, solvent violet 13, solvent violet 37, solvent violet 59, solvent yellow 1, solvent yellow 2, solvent yellow 3, solvent yellow 7, solvent yellow 14, solvent yellow 33, solvent yellow 72, solvent yellow 93, solvent yellow 94, solvent yellow 98, solvent yellow 114, solvent yellow 141, solvent yellow 16 0, solvent yellow 16 3.

26. according to any one particle swimming box in each claim of front, wherein, swimming particle or each swimming particle are applicable to the electromagnetic radiation of reflecting incident on it.

27. according to the particle swimming box of claim 26, wherein, swimming particle or each swimming particle have and comprise the reflective coating of one of metallic coating and dielectric coated at least.

28. according to any one particle swimming box among the claim 1-26, wherein, swimming particle or each swimming particle comprise a kind of composite particles, this composite particles has a plurality of scattering particles that are applicable to scattering electromagnetic radiation of incident on it that are dispersed in the carrier.

29. according to the particle swimming box of claim 28, wherein, carrier comprises polymkeric substance.

30. according to the particle swimming box of claim 29, wherein, carrier comprises polymethylmethacrylate (PMMA).

31. according to any one particle swimming box among the claim 28-30, wherein, scattering particles comprise polymer drops, each polymer drops is incorporated into one of adamas of weak breath body cavity and pulverizing.

32. according to any one particle swimming box in each claim of front, wherein, liquid crystal material is the nematic liquid crystal material.

33. according to any one particle swimming box in each claim of front, wherein, impressed field is one of electric field and magnetic field at least.

34. one kind basically as before this with reference to the described particle swimming of Fig. 3 in the accompanying drawing-8 box.

35. one kind is used for making among the claim 6-18 among any one described or claim 6-18 the method for any one described particle swimming box among any one dependent claims 23-33, this liquid crystal cell has a plurality of swimming particles that are suspended in the liquid crystalline suspension medium, and the method comprises the following step:

(i) preparation first substrate, it has and is applicable to liquid crystalline suspension medium and interacts with the first releasing structure alignment of preferred alignment that liquid crystal aligning in the particle swimming box is provided,

(ii) form a plurality of depressions in the releasing structure alignment, each depression has the inside surface that extends from the releasing structure surface of releasing structure alignment,

(iii) the swimming particle is deposited on the first releasing structure surface,

(iv) liquid crystalline suspension medium is combined in the box.

36. according to the method for the manufacturing particle swimming box of claim 35, it comprises the following step:

(v) prepare second substrate, it has and is applicable to liquid crystalline suspension medium and interacts with the second releasing structure alignment of preferred alignment that liquid crystal aligning in the particle swimming box is provided,

(vi) form a plurality of depressions in the second releasing structure alignment, each depression has the inside surface that extends from the releasing structure surface of the second releasing structure alignment,

(vii) second substrate is arranged in away from first substrate, its releasing structure alignment and liquid crystalline suspension medium are interacted, so that the preferred alignment of liquid crystal aligning in the electrophoretic display device (EPD) is provided.

37. method according to claim 36, it comprises each depression in the releasing structure surface of the first releasing structure alignment is arranged to the step that the respective recesses in the releasing structure surface with the second releasing structure alignment is faced basically, and it is right that described each is recessed to form the depression of facing.

38. according to the method for claim 37, it comprises the swimming particle is arranged in the internal step of each depression of facing.

39. according to the method for claim 35-38, wherein, one of at least the first and second substrates comprise one of polymkeric substance and prepolymer at least, and the step that forms a plurality of depressions in the releasing structure surface comprises embossed technology.

40. according to the method for claim 35-38, wherein, one of at least the first and second substrates comprise photopolymer, and the step of a plurality of depressions in the formation releasing structure surface comprises photoetching process.

41. the display with first display surface of the displayed image of being used for, it comprises any one described particle swimming box among the claim 1-33,

Wherein, particle swimming box is arranged in the display, makes first optimum position or each first optimum position in the liquid crystal cell be located substantially on the first display surface place,

By means of applied field on display, this display can be worked.

42. according to the display with second display surface of arranging away from first display surface of claim 41, it comprises any one described particle swimming box among the described or claim 2 dependent claims 3-33 of claim 2,

Wherein, particle swimming box is arranged in the display, makes second optimum position or each second optimum position in the liquid crystal cell be located substantially on the second display surface place, and

First and second optimum positions are such, and when being positioned at an optimum position place, swimming particle or each swimming particle can be seen at the display surface place, and when being positioned at another optimum position place, the place can't see at described display surface.

43. according to the display that comprises any one described particle swimming box among the described or claim 20 dependent claims 21-33 of claim 20 of claim 42, wherein, the liquid crystal drop integument is arranged in the encapsulation agent.

44. according to the display of claim 43, wherein, but encapsulation agent comprises at least a in heat-setting polymkeric substance electromagnetic radiation cured polymer and the silicone synthetic rubber.

45. according to the display of claim 43 or 44, wherein, encapsulation agent comprises DowCorning Sylgard 182.

46. according to any one display that comprises any one described particle swimming box among the described or claim 22 dependent claims 23-33 of claim 22 among the claim 43-45, wherein, the liquid crystal drop integument major axis that is arranged in each tear drop is substantially normal to the plane parallel with first display surface.

47., also comprise and be used on display, applying the device of one of electric field and magnetic field at least according to any one display among the claim 41-46.

48., wherein, be used for the device of applied field and comprise electrode according to the display of claim 47.

49. display according to any one dependent claims 48 among the claim 42-47, it comprises near the row that is arranged in first display surface and a plurality of electrodes near the row second display surface, the intersection point of each row and column electrode is determined a pixel in the display, so that can carry out matrix addressing to each pixel in the display.

50. according to the display of claim 48 or 49, wherein, at least a in electrode or each electrode package containing metal, tin indium oxide (ITO) and the conducting polymer.

51. one kind basically as before this with reference to Fig. 3 in the accompanying drawing-8 and 14 described displays.

52. a method of making any one described display among the claim 41-50, it comprises the following step:

(i) with claim 19 among described or its dependent claims 20-33 any one described a plurality of liquid crystal cell be distributed in the curable encapsulation agent,

(ii) each liquid crystal cell is aligned to preferred alignment,

(iii) encapsulation agent is cured, so that each liquid crystal cell is clamped in wherein.

53., also comprise the suspending liquid of liquid crystal cell and curable encapsulation agent be coated to step on the substrate according to the method for the manufacturing display of claim 52.

54. method according to the manufacturing display of claim 53, wherein, each liquid crystal cell is aligned to the step of preferred alignment, after being cured, encapsulation agent carries out, and comprise the encapsulation agent that expands and be cured along the direction that is substantially perpendicular to substrate, thereby be dispersed in the step of liquid crystal cell wherein along the direction elongation that is substantially perpendicular to substrate.

55. according to the method for the manufacturing display of claim 54, wherein, the step of the encapsulation agent that is cured of expanding comprises material is incorporated in the encapsulation agent of curing, heaves so that cause the encapsulation agent that is cured.

56. method according to the manufacturing display of claim 53, it comprises some intermediate steps, promptly before solidifying encapsulation agent, in substrate plane, make reversibly deformation of substrate, after solidifying encapsulation agent, make substrate get back to it then not by the state of deformation, so that carry out the step of aiming at liquid crystal cell, the encapsulation agent of curing be compressed in the plane parallel with substrate plane with the liquid crystal cell that is dispersed in wherein.

57. according to the method for the manufacturing display of claim 56, wherein, the step that substrate is carried out reversible deformation comprise to substrate heat and substrate stretched at least a.

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