CN100575050C - The forming method of thick light guiding plate and mold for forming - Google Patents

The forming method of thick light guiding plate and mold for forming Download PDF

Info

Publication number
CN100575050C
CN100575050C CN200510076563A CN200510076563A CN100575050C CN 100575050 C CN100575050 C CN 100575050C CN 200510076563 A CN200510076563 A CN 200510076563A CN 200510076563 A CN200510076563 A CN 200510076563A CN 100575050 C CN100575050 C CN 100575050C
Authority
CN
China
Prior art keywords
described
die cavity
light guiding
core block
guiding plate
Prior art date
Application number
CN200510076563A
Other languages
Chinese (zh)
Other versions
CN1727169A (en
Inventor
横山和久
中岛英昭
沖庸次
矶部文敏
武内敦
中川隆
Original Assignee
株式会社日本制钢所
斯坦雷电气株式会社
不二精机株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to JP2004171330A priority Critical patent/JP4087818B2/en
Priority to JP171330/04 priority
Application filed by 株式会社日本制钢所, 斯坦雷电气株式会社, 不二精机株式会社 filed Critical 株式会社日本制钢所
Publication of CN1727169A publication Critical patent/CN1727169A/en
Application granted granted Critical
Publication of CN100575050C publication Critical patent/CN100575050C/en

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C45/00Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
    • B29C45/17Component parts, details or accessories; Auxiliary operations
    • B29C45/70Means for plasticising or homogenising the moulding material or forcing it into the mould, combined with mould opening, closing or clamping devices
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C45/00Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
    • B29C45/17Component parts, details or accessories; Auxiliary operations
    • B29C45/46Means for plasticising or homogenising the moulding material or forcing it into the mould
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C45/00Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
    • B29C45/17Component parts, details or accessories; Auxiliary operations
    • B29C45/72Heating or cooling
    • B29C45/73Heating or cooling of the mould
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C45/00Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
    • B29C45/17Component parts, details or accessories; Auxiliary operations
    • B29C45/72Heating or cooling
    • B29C45/73Heating or cooling of the mould
    • B29C45/7331Heat transfer elements, e.g. heat pipes
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS, OR APPARATUS
    • G02B5/00Optical elements other than lenses
    • G02B5/02Diffusing elements; Afocal elements
    • G02B5/0268Diffusing elements; Afocal elements characterized by the fabrication or manufacturing method
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C45/00Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
    • B29C45/17Component parts, details or accessories; Auxiliary operations
    • B29C45/72Heating or cooling
    • B29C45/73Heating or cooling of the mould
    • B29C2045/7393Heating or cooling of the mould alternately heating and cooling

Abstract

A kind of forming method that can mold the high-quality thick light guiding plate with short molding cycle is provided.Both quantitative molten resin is filled into by the insert core block (23) and the perisporium of the die (8) on (4), mobile mould of the die cavity that is arranged on fixed die inserts in the excipient space (K) that (30,30) constitute.Afterwards, valve gate is closed and compress with core block (23).Compress and to improve replicability, can also shorten molding cycle.When compressing, the insert temperature of (30,30) of perisporium is higher than that die cavity is inserted (4) and the temperature of core block (23).Like this, can make the insert cooling velocity of (30,30) of perisporium slack-off, improve and carry out compression effects, suppress to shrink the generation of pit.

Description

The forming method of thick light guiding plate and mold for forming

Technical field

The forming method and the mold for forming of the LGP that the synthetic resin that the present invention relates to use as the bias light of LCD is made, though limit, relate to be suitable for moulding for example thickness be the forming method and the mold for forming of the above large-scale thick light guiding plate of 6mm.

Background technology

The liquid crystal indicator of computer, LCD TV etc. is made of LCD and LGP.And, be provided with light source at the sidepiece of LGP.Therefore, the light that comes out of this light source radiation is subjected to being formed at the reflection of the reflector layer on the one side of LGP and penetrates from penetrating the light face.Throw light on by the whole face of this light to LCD.

This LGP is that acrylic resin board is cut into both sizings, prints patterns such as point-like, groove shape more in its surface and makes.But, in the monitor field, the phenomenon that changes to LCD from cathode-ray tube CRT is taking place, acrylic resin board, particularly thicker acrylic resin board under-supply, people wish to supply with injection molding LGP.

As everyone knows, injection moulding by cartridge heater and be arranged in this cartridge heater can be along direction of rotation and the screw rod that axially freely drives constituting.Therefore, when the drive screw rotation of resin material limit is supplied with on the limit in cartridge heater, resin material is in the process of forwards being carried by screw rod, fusion under the effect of the heat that can be produced in the spin friction power or the shearing force of heat that the periphery from cartridge heater applies and screw rod, and savings is in the measuring room in cartridge heater the place ahead.Therefore, be injected into the excipient space of the mould that is in the matched moulds state, after the curing to be cooled mould opened just and can obtain the moulding product.But, with regard to the reflective surface of LGP, require to have good replicability, and require to mold the high-quality moulding product that do not have vestiges such as land area.With regard to the reflective surface pattern copies to replicability on the LGP, improve the surface temperature in excipient space, molten resin good flow thereby replicability are improved.But, will cause the time lengthening of the cooling curing that carries out in order from mould, to take out, molding cycle prolongs.For this reason, patent documentation 1~4 has proposed to force to heat, fill the thermal cycling method that pressure is cooled off when carrying out pressurize after being over when molten resin is filled in injection.

[patent documentation 1] special public clear 45-22020 communique

[patent documentation 2] spy opens clear 51-22759 communique

[patent documentation 3] spy opens clear 55-109639 communique

[patent documentation 4] spy opens clear 57-16522 communique

[patent documentation 5] spy opens 2001-18229

[patent documentation 6] spy opens 2002-210795

[patent documentation 7] spy opens flat 9-155875 communique

[patent documentation 8] spy opens 2002-46159

Forming method after patent documentation 5 propositions further improve above-mentioned thermal cycling method.That is, propose a kind ofly between mould and die insert, heat insulation layer to be set, make to add near the cavity surface that hot media and cooling medium flow into die insert mould.In addition, it is half hot flow path mode that patent documentation 6 proposes a kind of resin feed path, and heating cooling Media Stream path is set in the part of described resin passage, alternately cavity surface is heated the mould of cooling.

Utilize the forming method of injection moulding formed light conductive plate also to have open at patent documentation 7,8.That is, patent documentation 7 is disclosed to be, on the surface that constitutes the mould molding face with have the die for injection molding that is provided with heat insulation layer between the metallic plate of the patterned surfaces of making concavo-convex matsurface.And patent documentation 8 is disclosed be, in the scope of viscosity at 50~5000Pasec of molten resin the time, make it from cast gate by and with 1~15cm 3The injection rate of/sec scope is injected the forming method of filling in the die cavity of mould.

According to the forming method that patent documentation 1~4 proposes, when cavity surface is heated to form high temperature, fill, thereby can access the extraordinary moulding product of replicability, in addition, owing to force to cool off, thereby have the short advantage of molding cycle.According to the method for patent documentation 5 record, have the heating of cavity surface and alternately can the finishing of cooling of mould in the short period, can increase the flowability of molten resin by heating mould, can be forming thin-walled etc. characteristics.According to the invention of patent documentation 6 records, owing to adopt thermal cycling method, and heat insulation layer is set in the part of resin feed path, therefore, have the effect that can be suppressed at the small contraction pit of moulding product surface generation, streak (hesitation) etc.Invention according to patent documentation 7 records, at mould and have between the metallic plate of patterned surfaces and be provided with heat insulation layer, therefore, but when injecting the high-temperature fusion resin of injection moulding, mould can fully be duplicated die surface by temporary heating, and according to the invention of patent documentation 8 record, inject with low speed, thereby can suppress to shrink the generation of pit, can produce the bigger goods of thicker area.

But, in the above-mentioned existing forming method, exist in the moulding too many shortcoming that for example expends time in during the thick light guiding plate more than the 6mm.The particularly invention of patent documentation 8 is in the scope of viscosity at 50~5000Pasec of molten resin the time, makes it to pass through from cast gate, with 1~15cm 3The injection rate of/sec scope is injected, and therefore, might cause molding cycle long.In addition, if carry out the moulding of the thick light guiding plate of thickness more than 6mm with the above-mentioned thermal cycle method of forming, then pressurize operation will reach for example 90 seconds, implement the problem of existing.

On the other hand, in the excipient space of mould, fill both quantitative molten resin, drive mobile mould and move and method for injection compression molding that the molten resin of filling is compressed is also known to the matched moulds direction.Therefore, if this method for injection compression molding and the above-mentioned thermal cycle method of forming are made up, after both filling quantitatively, will close and compress as the cast gate of the path of molten resin, then the pressurize activity time will be zero in fact, after the filling immediately drive screw rotate into measurement process with the resin material fusion, therefore, can shorten molding cycle.But, produce depression, promptly shrink pit or indenture on the surface of thick light guiding plate sometimes, obviously reduce as its quality of LGP.

Summary of the invention

The present invention be directed in the past that the problems referred to above of existing propose, its objective is provides a kind of forming method and mold for forming that can mold the thick light guiding plate of high-quality thick light guiding plate with short molding cycle.

For reaching above-mentioned purpose of the present invention, the present invention has adopted following scheme.

(1) shortening of dwell time: when carrying out moulding with injection moulding, thereby in order to prevent owing to volume produces the contraction pit along with cooling curing dwindles on the surface of moulding product, implement to apply the pressurize operation of certain resin pressure from cast gate, but if use general general mould, this pressurize operation need reach 90 seconds time when the thicker moulding product of for example moulding.

But, if after both quantitative molten resin is filled in the injection of the excipient space of mould, to close as the cast gate of the path of molten resin, driving mobile mould moves to compress to the matched moulds direction, then can make the pressurize activity time be essentially zero, can be after filling immediately drive screw rotate into measurement process with the resin material fusion.For this reason, adopted method for injection compression molding in the present invention.At this moment, cast gate adopts valve gate, and runner adopts hot flow path.

According to the present invention, the excipient space of moulding thick light guiding plate by be used for this thick light guiding plate of moulding the two sides die cavity and core rod and be used for the perisporium of moulding side face and constitute, but move and when the both quantitative molten resin of being filled compressed, the temperature of described perisporium will be higher than the temperature of die cavity and core rod to the matched moulds direction driving mould.The cooling velocity in formed excipient space is that its perisporium is faster than die cavity or core rod on the mould.Because cooling velocity is fast, thereby only depends on compression can't remedy the thermal shrinking quantity that takes place along with cooling, can produces on the surface of thick light guiding plate and shrink pit, and the temperature of raising perisporium, make it cool off slowly, then can give full play to compression effects, suppress to shrink the generation of pit.For example, during with acrylic resin moulding thick light guiding plate, for the cooling velocity of slowing down perisporium to improve compression effectiveness, the temperature of perisporium will remain on 120~130 ℃.

(2) shortening of filling time: in general, filling time is short then easily in cast gate periphery generation weld line, silver color open defects such as (silver), therefore to make the filling time long enough, but in the present invention, according to the thickness of thick light guiding plate, design the diameter of valve gate and the thickness of switch over travel and cast gate bigger within the bounds of possibility.Therefore, can shorten the filling time and can not produce open defect, and then molding cycle is shortened.

(3) low temperatureization of resin temperature and mold temperature: reduce the temperature of resin and the temperature of mould, can shorten the cooling curing time, thereby shortening molding cycle, but the temperature of resin and mould is low, the part that can cause the wall with constituting the excipient space of the molten resin injected contact began to solidify before compression pressure works, and made the replicability reduction of duplicating to thick light guiding plate.For this reason, in the present invention, adopted when injecting compression mould has been heated the so-called thermal cycle method of forming of cooling off rapidly after replicability, the filling to improve rapidly.Specifically, at resin is the occasion of methacrylic resin, resin temperature remain on for example 230 ℃, mold temperature remain on inject filling under the state more than 75 ℃ after, be cooled to 40 ℃ rapidly, take out after making the surface temperature of thick light guiding plate moulding product for example be reduced to 65 ℃ afterwards.

(4) employing of heat insulation layer: as mentioned above, reduce temperature decline, replicability reduction that mold temperature can cause being filled in the molten resin in the excipient space, therefore, in the present invention, on the wall that constitutes the excipient space, be provided with heat insulation layer.By heat insulation layer is set, can make the wall that constitutes the excipient space be in the temporary transient heated state of injected molten resin, compression pressure can fully work, and replicability is improved.This heat insulation layer is formed by amorphism heat-resistant polymer, polyimides, epoxy resin etc. such as polysulfones, polyether sulfones.For example, make polyimides closely connected on mould the time, can with the raw material solution coat of straight chain polymer polyimides on mould, heat again.Like this, can form polyimide layer at die surface as heat insulation layer.

The employing of (5) inserting: because as mentioned above, die cavity, core rod and perisporium will be heated cooling, thereby heater or cooling device will be set in mould.For this reason, preferably setting is inserted.That is, be provided with that die cavity is inserted, core block and perisporium insert.And setting can be carried out thermoregulator heat medium pipe and refrigerant pipe to it independently in these are inserted.In addition, to be heated rapidly cooling rapidly because these are inserted, thus preferably by the good alloy of thermal conductivity for example beryllium-copper alloy form.Use the good alloy of this thermal conductivity, compare, can make the rise time of the temperature of inserting and fall time shorten to about 1/2 with inserting of stainless steel manufacturing.

(6) use of die: according to the present invention, for the surface at thick light guiding plate forms reflector layer, need on die cavity template or core rod template, form patterns such as point-like, groove shape, but use die cavity to insert and the occasion of core block, it can be formed on these insert.Perhaps, use the die that is formed with patterns such as point-like, groove shape.This die for example can be according to patent documentation 7 disclosed method manufacturings.At this moment, foregoing heat insulation layer can also be set at the back side of die.

As mentioned above, to achieve these goals, the forming method of thick light guiding plate provided by the present invention is a kind of by injection process, compression section and the forming method that takes out the operation formation, this injection process is that both quantitative molten resin is filled into die cavity template by fixed die via hot flow path and valve gate, the core rod template of mobile mould, and the open space that will constitute by described die cavity template and core rod template around operation in the excipient space that constitutes of the perisporium of sealing, this compression section is after described injection process described valve gate to be closed, driving described mobile mould moves and operation that the molten resin of filling is compressed to the matched moulds direction with respect to described fixed die, this taking-up operation is through supercooling mobile mould to be opened after described compression section, will go out the operation of the LGP taking-up of reflector layer pattern by described die cavity template or described core rod template duplicating; When carrying out described injection process, the temperature of described die cavity template, described core rod template and described perisporium is adjusted, and described compression section is to implement under the state of the temperature that is higher than described die cavity template and described core rod template of the temperature at described perisporium.

In addition, the forming method of thick light guiding plate provided by the present invention is a kind of by injection process, compression section, and the forming method that takes out the operation formation, this injection process is both quantitative molten resin to be filled into by the die cavity of fixed die via hot flow path and valve gate insert, the core block of mobile mould, and will by described die cavity insert and the open space that constitutes of core block around insert operation in the excipient space that constitutes of the perisporium of sealing, this compression section is after described injection process described valve gate to be closed, driving described mobile mould moves and operation that the molten resin of filling is compressed to the matched moulds direction with respect to described fixed die, this taking-up operation is through supercooling described mobile mould to be opened after described compression section, will insert or described core block copies the operation that the LGP of reflector layer pattern takes out by described die cavity; When carrying out described injection process, the temperature that described die cavity is inserted, described core block and described perisporium are inserted is regulated, and, described compression section be the temperature that described perisporium is inserted be higher than that described die cavity is inserted and the state of the temperature of described core block under implement.

In addition, according to the present invention, be described die cavity insert or described core block on be provided be used for moulding reflector layer pattern die and carry out moulding.

In addition,, the die that is used for duplicating the reflector layer pattern is set on described die cavity is inserted, on the surface of described core block heat insulation layer is set, and under described core block is cooled water-cooled situation at ordinary times, carries out moulding according to the present invention.

In addition, according to the present invention, in front that described die cavity is inserted the die that is used for duplicating the reflector layer pattern is set, heat insulation layer is set, and insert and described core block is cooled at ordinary times and carries out moulding under the water-cooled situation at described die cavity at the back side of described die and the surface of described core block.

In addition, according to the present invention, the heating of described die cavity template, described core rod template and described perisporium cooling is undertaken by a heating-cooling device, and the switching sequence of hot media and refrigerant body is adjusted separately in molding cycle.

In addition, the heating cooling that according to the present invention, described die cavity is inserted, described core block and described perisporium are inserted is undertaken by a heating-cooling device, and the switching sequence of hot media and refrigerant body is adjusted separately in molding cycle.

In addition, according to the present invention, will be placed on the thick light guiding plate that said method obtains on the chilled bottom cooling mold, and push down with same chilled top cooling mold, when thick light guiding plate is cooled off, clamp and carry out warpage to pushing tow direction imposed load and correct with described two molds.

The mold for forming of thick light guiding plate provided by the present invention is a kind of like this mould, promptly, can constitute to the mobile mould that the matched moulds direction is compressed by fixed die with after filling both quantitative molten resin, formed excipient space is communicated with hot flow path via the able to turn on or off valve gate of resin passage during these mould matched moulds, when from described hot flow path when molten resin is filled in excipient space injection, by described fixed die or mobile mould reflective surface is copied on the thick light guiding plate; Described fixed die and mobile mould are heated and cool off, and the temperature of perisporium that constitutes the perimembranous in described excipient space can be independent of described fixed die and mobile mould is regulated.

In addition, the mold for forming of thick light guiding plate provided by the present invention is a kind of like this mould, promptly, can constitute to the mobile mould that the matched moulds direction is compressed by fixed die with after filling both quantitative molten resin, described fixed die is provided with die cavity and inserts, described mobile mould is provided with core block, and, insert or the periphery of described core block is provided with perisporium and inserts at described die cavity, when described mobile mould during with respect to described fixed die matched moulds, insert by described die cavity, described core block and described perisporium are inserted and are formed the excipient space, this excipient space is communicated with hot flow path via the able to turn on or off valve gate of resin passage, when from described hot flow path when molten resin is filled in described excipient space injection, insert or described core block can copy to reflective surface on the thick light guiding plate by described die cavity; Described die cavity insert and described core block can be heated and cool off, and, the temperature that described perisporium is inserted can be independent of described die cavity insert and described core block regulate.

In addition, according to the present invention, described die cavity is inserted to be provided with and is used for the reflector layer pattern is copied to the lip-deep die of thick light guiding plate.

In addition, according to the present invention, be provided with heat insulation layer on the surface of described core block.

In addition, according to the present invention, between inserting, the back side of the surface of described core block and described die and described die cavity be provided with heat insulation layer.

In addition, according to the present invention, described die cavity is inserted, described core block and described perisporium are inserted is made of beryllium-copper alloy.

As mentioned above, the present invention is the part of inscape of compression section as invention, and therefore, resin material is become can injection moulding, shortens molding cycle.At this moment, when carrying out injection process, the temperature of die cavity, core rod and perisporium for example regulated heat, therefore, can make molten resin keep very high flowability, in addition, compression section is to implement under the state of the temperature that is higher than die cavity and core rod of the temperature at perisporium, therefore, can access the peculiar effect of the present invention, that is, have excellent replicability, the generation that pit is shunk on the thick light guiding plate surface can be suppressed, and the thick light guiding plate of excellent optical property can be obtained having with short molding cycle.

In addition, according to other scheme, the excipient space constitutes by inserting, and therefore, can also obtain can be at an easy rate heating or cooling device being installed in these effects in inserting, and can constitute the effect of inserting with suitable material.And, except having above-mentioned effect, can also obtain the extraordinary thick light guiding plate of replicability according to the invention that is provided with die.In addition, insert or core block is provided with the invention of heat insulation layer according to die cavity, even inject filling under the state that die cavity is inserted or core block is cooled at ordinary times, the excipient space also can be in the temporary transient heated state of high-temperature fusion resin that is filled, and can not cause replicability to reduce.Since die cavity is inserted or core block by regular cooling, therefore, can access the effect that shortens cool time thereby shorten molding cycle.

Description of drawings

Fig. 1 is the schematic cross sectional views that the state when the related thick light guiding plate mold for forming of embodiment of the present invention is opened is showed.

Fig. 2 is the accompanying drawing that the state when the related mould of use embodiment of the present invention is carried out moulding is showed, (A) being the cutaway view that the state when filling both quantitative molten resin behind the matched moulds is showed, (B) is that the both quantitative molten resin of being filled is carried out cutaway view under the compressive state.

Fig. 3 is the cutaway view under the state of mould being opened in order to take out thick light guiding plate.

The specific embodiment

At first, in conjunction with Fig. 1 the related mould of embodiment of the present invention is described.As shown in Figure 1, the mould of preferred forms of the present invention is that its fixed die 1 is provided with die cavity and inserts 4, and mobile mould 20 is provided with core block 23, and the peripheral part of core block 23 is provided with perisporium and inserts 30,30.In addition, mobile mould 20 is made of compressible mould.

Fixed die 1 is installed on the fixed die installing plate 15.Be formed with both the 1st recesses 2 of sizing in the parting line P of fixed die 1 side, around the 1st recess 2, be formed with the 2nd more shallow recess 3.Die cavity is inserted and 4 is installed in the 1st recess 2 by holding member 5, is provided with guide member 7 in the 2nd recess 3, and this guide member 7 has along with the inclined plane 6 away from the tapered inclination of parting line P.This guide member 7 can be to perisporium described later 30,30 channeling conducts of inserting.Die cavity is inserted and 4 is made of the good for example beryllium-copper alloy of thermal conductivity, and its inside is provided with the pipe of the heating cooling usefulness that Fig. 1 cooling medium that add hot media and about 20 ℃ unshowned, about 150 ℃ alternately flow.In addition, the die 8 that is formed with patterns such as point-like, groove shape is installed in die cavity by holding member 9 and inserts on 4 the surface.Perhaps, adsorb by a plurality of vacuum absorbers from insert 4 the back side of die cavity.

The front opening of valve gate 10 is in the die cavity that as above constitutes 4 the sidepiece of inserting.Fig. 1 is the schematic cross sectional views of embodiment of the present invention, draws to such an extent that be not very accurate, but the diameter of the front end of this valve gate 10 and the Thickness Design of cast gate that opens and closes stroke and flow into the inflow entrance in excipient space as resin get big as far as possible.For example, in size is that 18 inches, thickness are that the product weight of the LGP of 12mm is the occasion of 1500gr, the diameter of valve gate is that the keying stroke of 5mm, needle-valve is 30mm, be 1.5~2 times of common valve gate, and the thickness of cast gate is and the identical in fact 12mm of moulding product thickness.So, with respect to needed 25~30 second filling time of the valve gate in past, can finish filling with 12~15 seconds high speed.Owing to design greatlyyer, even thereby finish injection at short notice in order to shorten molding cycle, also can not produce open defects such as weld line, silver color at the periphery of cast gate.According to present embodiment, valve gate 10 is a hot runner, is formed with the tapered seat 12 that dwindles of diameter within it in the resin passage 11 of portion.In addition, be provided with the valve rod 13 that can arrive fixed die installing plate 15 places in this resin passage 11.This valve rod 13 breaks away from thereby can move vertically or be located in the seat 12 or from seat 12 under the driving of the interior piston/cylinder unit 14 that is contained in hydraulic pressure in the fixed die installing plate 15 or air pressure.Thus, the resin passage 11 of valve gate 10 can be closed or opened.Locating ring 16 is installed on the fixed die installing plate 15, and the hot flow path 18 of down gate 17 through being arranged between fixed die installing plate 15 and the fixed die 1 is communicated with resin passage 11 between the valve gate 10.

With the paired mobile mould 20 of fixed die 1 be by being installed in can and be positioned at its inboard core block 23 to the cushion block 22 of parting line P side shifting and constitute on the mobile mold mounting plate 21 in the present embodiment.More particularly, cushion block 22 and core block 23 can move freely to parting line P side by many pilot pins 26, and cushion block 22 is subjected to being arranged on the effect of elastic force of sensing parting line P side of the spring 27 of many places.Therefore, under the state that mould shown in Figure 1 is opened, between the front surface of the rear surface of cushion block 22 and mobile mold mounting plate 21, can form set decrement D.In addition, core block 23 can be returned and its rear surface is contacted with mobile mold mounting plate 21 front surfaces.It is 4 same that core block 23 and the aforementioned die cavity that constitutes like this inserted, and is made of beryllium-copper alloy, and portion is provided with heating cooling that Fig. 1 cooling medium that add hot media and about 20 ℃ unshowned, about 150 ℃ alternately flow with pipe within it.

Be provided with at the periphery of the core block 23 that as above constitutes and be divided into a plurality of perisporiums and insert 30,30.These perisporiums insert the 30, the 30th, for mold for example square thick light guiding plate around the side, take out easily in order to make thick light guiding plate, made slidingtype.That is,,, can and become big direction in the direction that this square area is diminished and slide for square thick light guiding plate according to present embodiment.Since be separate, can slide, therefore, though under the state that mould shown in Figure 1 is opened, have gap s, s between perisporium is inserted the end outer peripheral face of 30,30 medial surface and core block 23, this gap s just disappears behind the matched moulds.The perisporium of Gou Chenging is inserted and 30,30 also is made of beryllium-copper alloy like this, and portion is provided with and adds heating cooling that hot media and cooling medium alternately flow with pipe within it.In addition, the recess 31 that can engage with the holding member 9 of die 8 when its parting line P side is formed with matched moulds is formed with the conical surface 32,32 that tilts towards front end on its periphery.These conical surfaces 32,32 contact with the inclined plane 6 of guide member 7 when matched moulds, with perisporium 30, the 30 inside channeling conducts of inserting.

As above-mentioned die cavity insert 4, core block 23 and perisporium insert 30,30, as previously mentioned, particularly insert in 30,30 at perisporium, add hot media and cooling medium and be independent of other and insert and 4,23 flow, the heating cooling source of transferring unit, cooling unit and heat exchanger to constitute by temperature that for this reason is provided with is not shown in Fig. 1.In addition, according to present embodiment,, be that surface temperature at the moulding product is taken out thick light guiding plate when for example being cooled to 65 ℃ of left and right sides from mould in order to shorten molding cycle, but under this temperature, copying to the lip-deep pattern of thick light guiding plate might be out of shape because of waste heat.For this reason, in the present embodiment, to cool off with outside cooling device the thick light guiding plate that takes out.The external refrigeration device is not shown in Fig. 1, is to be made of bottom cooling mold that is shallow box-like and top cooling mold.These cooling molds are cooled off by refrigerant.In addition, top cooling mold also plays a part gland, if the thick light guiding plate that will take out from mould is placed on the bottom cooling mold, again top is cooled off mold be placed on it above, with two molds it is clamped, and with pneumatic cylinder, pressure is first-class applies suitable load to the pushing tow direction, then when thick light guiding plate is cooled off, can also carry out warpage and correct.

In order to prevent to damage thick light guiding plate, the screening glass that is formed by epoxy resin etc. can also be set on these surfaces of cooling off mold.

Below, describe with regard to the example that uses above-mentioned mould molding thick light guiding plate.Make mobile mould 20 with respect to fixed die 1 matched moulds.So, insert 4 die 8 and the interval between the core block 23 of die cavity is installed will for example be 12mm.In addition, along with the carrying out of mould assembling action, insert 30,30 the conical surface 32,32 of perisporium is subjected to the guiding on the inclined plane 6,6 of guide member 7,7, the contacts side surfaces of its medial surface and core block 23.Like this, shown in Fig. 2 (A), constituted airtight excipient space K by insert 30,30 medial surface of the surface of die 8, core block 23 and perisporium.At this moment, can guarantee to have decrement D between the front surface of the rear surface of cushion block 22 and mobile mold mounting plate 21.For die cavity insert 4, core block 23 and perisporium insert 30,30, for example make 150 ℃ flow heated water go into heat medium pipe and heat.

Though not shown, by well-known injector, with injection material, for example acrylic resins such as both quantitative acrylic resin, polystyrene, Merlon, making it according to well-known mode of past can the ormal weight injection moulding.Inject afterwards.Molten resin from down gate 17, hot flow path 18 and valve rod 13 keep out of the way and the valve gate 10 opened by after be filled among the K of excipient space.Both filled quantitatively but the state that also has the space that is not filled shown in Fig. 2 (A), utilize the piston/cylinder unit 14 of hydraulic pressure that the front end of valve rod 13 is located in the seat 12 and resin passage 11 closed.And, drive mobile mould 20 with clapper die spotting press and move and begin to compress to the matched moulds direction.Along with the carrying out and the resin that compress cool off gradually, decrement D will move closer in zero.Fig. 2 (B) illustrates that decrement D is almost equal to zero, the state of mould before being about to open.When beginning to compress, in order to shorten molding cycle since die cavity insert 4 and the thermal capacity of core block 23 big, also can begin to cool off by for example 20 ℃ cooling water.Insert 30,30 for perisporium, make to add that hot media continues to flow into and insert 4 and the temperature of core block 23 so that it is kept above die cavity.Occasion at the injection acrylic resin, make perisporium 30,30 above for example 120~130 ℃ the high temperature of glassy state inversion point that remain on acrylic resin of inserting, can suppress the cooling curing of thick light guiding plate on thickness direction, therefore, compressed action can be followed well and is filled in the volume contraction that the molten resin in the K of excipient space produces along with cooling.Therefore, can suppress the generation that pit is shunk on moulding product surface.Making the cooling medium also flow into perisporium after compression finishes inserts and 30,30 cools off.When moulding product surface temperature for example is reduced to 65 ℃, mobile mould 20 is opened.State when mobile mould 20 is opened is shown in Fig. 3.For example holding thick light guiding plate S with sucker takes out it, be put on the bottom cooling mold of external refrigeration device, top being cooled off mold is placed on above it again, with two molds it is clamped, if utilize pneumatic cylinder, pressure is first-class applies suitable load to the pushing tow direction, then, except its inside is fully cooled off, can also carry out warpage and correct for thick light guiding plate.Thus, can access high-quality thick light guiding plate.Continue afterwards to carry out moulding with same method.

The present invention is not subjected to the qualification of above-mentioned embodiment, and various flexible programs can also be arranged.For example, according to above-mentioned embodiment, owing to be provided with and insert 4,23,30, thereby insert 4,23,30 when constituting by the good material of thermal conductivity when these, can improve response to the heating cooling, and be convenient to the installing of heat medium pipe or refrigerant pipe, but obviously, these are not set insert and 4,23,30 can implement yet.In addition, insert 4 or core block 23,, also can cool off with for example 30 ℃ cooling water at ordinary times, can also heat insulation layer be set on these surfaces of 4,23 of inserting in order to shorten molding cycle for die cavity.By heat insulation layer is set, can utilize the molten resin of filling to make the wall that constitutes the excipient space be in temporary transient heated state, can prevent the reduction of replicability.

In addition, in the occasion that die is arranged on the core block, also can implement like this, that is, making its thickness is 1~5mm, and by a plurality of magnet that are installed on the core block 23 it is carried out sticking.In addition, also a plurality of projectioies can be set, utilize these projectioies to install with screw from core block 23 1 sides at the back side of die.In addition, according to above-mentioned embodiment, die 8 is arranged on die cavity and inserts on 4, but also pattern can be formed directly into die cavity insert 4 or core block 23 on.Pattern can also be formed directly on the mould.

Embodiment (Comparative Examples): use die cavity to insert and go up the die that installation is formed with dot pattern, core block is made the mould of minute surface, with various forming methods (Comparative Examples 1, embodiment 1,2 and 3) moulding size is that 18 inches, thickness are the LGP of 12mm, with regard to molding cycle and shrink LGP Products Quality such as pit, replicability, warpage and compare.It the results are shown in table 1.

For shrinking pit, to fixed its thickness of 4 angular measurements that are easy to generate the moulding product that shrink pit, calculate according to maximum ga(u)ge-minimum thickness with the amesdial slide calliper rule.Test example 1 is a Comparative Examples 1, and test example 2,3 and 4 is respectively embodiment 1,2 and 3.

The comparison example of table 1 moulding process and molding cycle and moulding product quality

Comparative Examples 1: adopting the forming temperature of mould constant is that 80 ℃ common injection moulding method carries out moulding.Though the quality of moulding product is roughly qualified, molding cycle reaches 372 seconds.

Embodiment 1: making perisporium insert constant with core block is 90 ℃, only die cavity is inserted and heated cooling between 85 ℃ and 40 ℃, carries out compression forming.Molding cycle shortens to 260 seconds, but its quality is relatively poor aspect contraction pit, replicability, warpage.

Embodiment 2: perisporium is inserted brought up to 110 ℃, die cavity is inserted heated cooling between 104 ℃ and 45 ℃, core block is heated cooling between 83 ℃ and 38 ℃, carry out compression forming.

Molding cycle shortens to 200 seconds, and contraction pit aspect is poor slightly, but is obtaining good result aspect replicability, the warpage.

Embodiment 3: perisporium is inserted heated cooling between 130 ℃ and 35 ℃, die cavity is inserted heated cooling between 110 ℃ and 35 ℃, form heat insulation layer and be cooled to 35 ℃ on the surface of core block, carry out compression forming.

When the temperature of inserting at perisporium is higher than when implementing the heating cooling under the state of temperature that die cavity inserts and carrying out compression forming, molding cycle has shortened to 175 seconds, and its quality is improved aspect pit, replicability, the warpage shrinking.

Claims (14)

1. the forming method of a thick light guiding plate, by injection process, compression section, and the taking-up operation constitutes, described injection process is that both quantitative molten resin is filled into die cavity template by fixed die via hot flow path and valve gate, the core rod template of mobile mould, and the open space that will constitute by described die cavity template and core rod template around operation in the excipient space that constitutes of the perisporium of sealing, described compression section is after described injection process described valve gate to be closed, driving described mobile mould moves and operation that the molten resin of filling is compressed to the matched moulds direction with respect to described fixed die, described taking-up operation is through supercooling mobile mould to be opened after described compression section, will go out the operation of the LGP taking-up of reflector layer pattern by described die cavity template or described core rod template duplicating; It is characterized in that,
When carrying out described injection process, the temperature of described die cavity template, described core rod template and described perisporium is adjusted, and described compression section is to implement under the state of the temperature that is higher than described die cavity template and described core rod template of the temperature at described perisporium.
2. the manufacturing process of thick light guiding plate as claimed in claim 1, it is characterized in that, the heating cooling of described die cavity template, described core rod template and described perisporium is undertaken by a heating-cooling device, and the switching sequence of hot media and refrigerant body is adjusted separately in molding cycle.
3. the forming method of a thick light guiding plate, by injection process, compression section, and the taking-up operation constitutes, described injection process is both quantitative molten resin to be filled into by the die cavity of fixed die via hot flow path and valve gate insert, the core block of mobile mould, and will by described die cavity insert and the open space that constitutes of core block around insert operation in the excipient space that constitutes of the perisporium of sealing, described compression section is after described injection process described valve gate to be closed, driving described mobile mould moves and operation that the molten resin of filling is compressed to the matched moulds direction with respect to described fixed die, described taking-up operation is through supercooling described mobile mould to be opened after described compression section, will insert or described core block copies the operation that the LGP of reflector layer pattern takes out by described die cavity; It is characterized in that,
When carrying out described injection process, the temperature that described die cavity is inserted, described core block and described perisporium are inserted is regulated, and, described compression section be the temperature that described perisporium is inserted be higher than that described die cavity is inserted and the state of the temperature of described core block under implement.
4. the manufacturing process of thick light guiding plate as claimed in claim 3 is characterized in that, described die cavity insert or described core block on be provided be used for moulding reflector layer pattern die and carry out moulding.
5. the manufacturing process of thick light guiding plate as claimed in claim 3, it is characterized in that, the die that is used for duplicating the reflector layer pattern is set on described die cavity is inserted, on the surface of described core block heat insulation layer is set, and under described core block is cooled water-cooled situation at ordinary times, carries out moulding.
6. the manufacturing process of thick light guiding plate as claimed in claim 3, it is characterized in that, in the front that described die cavity is inserted the die that is used for duplicating the reflector layer pattern is set, at the back side of described die and the surface of described core block heat insulation layer is set, and inserts and described core block is cooled at ordinary times and carries out moulding under the water-cooled situation at described die cavity.
7. the manufacturing process of thick light guiding plate as claimed in claim 3, it is characterized in that, the heating cooling that described die cavity is inserted, described core block and described perisporium are inserted is undertaken by a heating-cooling device, and the switching sequence of hot media and refrigerant body is adjusted separately in molding cycle.
8. the forming method of a thick light guiding plate, it is characterized in that, to be placed on the thick light guiding plate that claim 1 or 3 described manufacturing process obtain on the chilled bottom cooling mold, and cool off mold with same chilled top and push down, when thick light guiding plate is cooled off, clamp and carry out warpage to pushing tow direction imposed load and correct with described two molds.
9. thick light guiding plate mold for forming, can constitute to the mobile mould that the matched moulds direction is compressed by fixed die with after filling both quantitative molten resin, formed excipient space is communicated with hot flow path via the able to turn on or off valve gate of resin passage during these mould matched moulds, when from described hot flow path when molten resin is filled in excipient space injection, by described fixed die or mobile mould reflective surface is copied on the thick light guiding plate; It is characterized in that,
Described fixed die and mobile mould are heated and cool off, and the temperature of perisporium that constitutes the perimembranous in described excipient space can be independent of described fixed die and mobile mould is regulated.
10. thick light guiding plate mold for forming, can constitute to the mobile mould that the matched moulds direction is compressed by fixed die with after filling both quantitative molten resin, described fixed die is provided with die cavity and inserts, described mobile mould is provided with core block, and, insert or the periphery of described core block is provided with perisporium and inserts at described die cavity, when described mobile mould during with respect to described fixed die matched moulds, insert by described die cavity, described core block and described perisporium are inserted and are formed the excipient space, this excipient space is communicated with hot flow path via the able to turn on or off valve gate of resin passage, when from described hot flow path when molten resin is filled in described excipient space injection, insert or described core block copies to reflective surface on the thick light guiding plate by described die cavity; It is characterized in that,
Described die cavity is inserted and described core block is heated and cools off, and the temperature that described perisporium is inserted can be independent of that described die cavity is inserted and described core block is regulated.
11. thick light guiding plate mold for forming as claimed in claim 10 is characterized in that, on described die cavity is inserted, is provided with and is used for the reflector layer pattern is copied to the lip-deep die of thick light guiding plate.
12. thick light guiding plate mold for forming as claimed in claim 10 is characterized in that, is provided with heat insulation layer on the surface of described core block.
13. thick light guiding plate mold for forming as claimed in claim 11 is characterized in that, is provided with heat insulation layer between the back side of the surface of described core block and described die and described die cavity are inserted.
14. thick light guiding plate mold for forming as claimed in claim 10 is characterized in that, described die cavity is inserted, described core block and described perisporium are inserted is made of beryllium-copper alloy.
CN200510076563A 2004-06-09 2005-06-09 The forming method of thick light guiding plate and mold for forming CN100575050C (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP2004171330A JP4087818B2 (en) 2004-06-09 2004-06-09 Method for forming thick light guide plate
JP171330/04 2004-06-09

Publications (2)

Publication Number Publication Date
CN1727169A CN1727169A (en) 2006-02-01
CN100575050C true CN100575050C (en) 2009-12-30

Family

ID=35584503

Family Applications (1)

Application Number Title Priority Date Filing Date
CN200510076563A CN100575050C (en) 2004-06-09 2005-06-09 The forming method of thick light guiding plate and mold for forming

Country Status (4)

Country Link
JP (1) JP4087818B2 (en)
KR (1) KR101197419B1 (en)
CN (1) CN100575050C (en)
TW (1) TWI412800B (en)

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100631336B1 (en) 2006-05-25 2006-10-04 (주)폴리텍 The method of void free for molding product
JP4044608B1 (en) * 2006-12-19 2008-02-06 株式会社名機製作所 Injection compaction method for small light guide plate and small light guide plate
JP4335266B2 (en) * 2007-03-30 2009-09-30 株式会社名機製作所 Light guide plate injection compression molding die and light guide plate injection compression molding method
JP4878584B2 (en) * 2007-08-01 2012-02-15 株式会社名機製作所 Injection compression mold for light guide plate
WO2009028745A1 (en) * 2007-08-28 2009-03-05 Lg Electronics Inc. Injection moldings, injection-molding apparatus and method thereof
JP2009125976A (en) * 2007-11-20 2009-06-11 Nippon Yakin Kogyo Co Ltd Die for molding resin and molding method
JP4979627B2 (en) * 2008-03-31 2012-07-18 株式会社ホンダロック Resin molding method and mold apparatus for resin molding
WO2010098188A1 (en) * 2009-02-25 2010-09-02 コニカミノルタオプト株式会社 Mold assembly for injection molding
KR101384323B1 (en) * 2010-10-07 2014-04-10 주식회사 엘지화학 Molding device for injection compression molding and method using the same
JP5290388B2 (en) * 2010-12-20 2013-09-18 株式会社日本製鋼所 Thin-walled molding method
KR101394846B1 (en) * 2011-12-09 2014-05-13 더 재팬 스틸 워크스 엘티디 Molding method of thin molded article
JP2012179783A (en) * 2011-03-01 2012-09-20 Seiko Epson Corp Injection mold and injection molding method
JP2014113930A (en) * 2012-12-10 2014-06-26 Mitsubishi Chemicals Corp Vehicle structural member for mounting solar cell module and method for manufacturing the same
CN103286922B (en) * 2013-06-14 2015-06-03 东莞市奕东电子有限公司 Injection molding die of backlight guide plate and injection molding method
CN103454716A (en) * 2013-08-27 2013-12-18 北京京东方光电科技有限公司 Light guide plate, manufacturing method thereof, backlight module and display device
CN104690917B (en) * 2015-03-04 2017-03-01 上海小糸车灯有限公司 A kind of LED-light guide component double injection corner flowing process method
CN104999622B (en) * 2015-06-29 2017-06-13 上海化工研究院有限公司 A kind of thermoplastic resin heavy section casting product mold system
CN109249578A (en) * 2017-07-13 2019-01-22 城翊科技有限公司 Thick member plastic cement injection forming method and its mold

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07117144A (en) * 1993-10-22 1995-05-09 Dainippon Printing Co Ltd Production of light guide plate for plane light source
JPH08160226A (en) * 1994-12-07 1996-06-21 Ohtsu Tire & Rubber Co Ltd :The Method and device for manufacturing light guide plate
JP3601463B2 (en) 2000-05-26 2004-12-15 住友化学工業株式会社 Method for manufacturing large light guide plate having pattern
JP4684423B2 (en) * 2001-01-17 2011-05-18 三井化学株式会社 Synthetic resin injection mold and injection molding method using the same
JP2002283352A (en) 2001-03-23 2002-10-03 Ricoh Co Ltd Method for manufacturing plastic optical element

Also Published As

Publication number Publication date
JP2005349646A (en) 2005-12-22
KR20060048245A (en) 2006-05-18
TW200634360A (en) 2006-10-01
JP4087818B2 (en) 2008-05-21
TWI412800B (en) 2013-10-21
CN1727169A (en) 2006-02-01
KR101197419B1 (en) 2012-11-05

Similar Documents

Publication Publication Date Title
Huang et al. The effective factors in the warpage problem of an injection-molded part with a thin shell feature
CN100593464C (en) Mold for injection molding machine
US6276656B1 (en) Mold for optimizing cooling time to form molded article
US6156242A (en) Method of injection molding plastic lens
EP0178901B1 (en) Methods of forming articles by injection moulding
TW490388B (en) Mold and molding machine for making ophthalmic devices
KR100850308B1 (en) Synthetic resin molding mold
JP3857703B2 (en) Manufacturing method and manufacturing apparatus of molded body
US5376317A (en) Precision surface-replicating thermoplastic injection molding method and apparatus, using a heating phase and a cooling phase in each molding cycle
KR100644926B1 (en) Injection molding apparatus having separation type mold and controlling method thereof
JP3977565B2 (en) Mold for synthetic resin molding, mold temperature control device and mold temperature control method
US6521146B1 (en) Compression molding of optical lenses
US6705725B2 (en) Injection compression molding method for optically molded products
US4372741A (en) Hot sprue valve assembly for an injection molding machine
US6869197B2 (en) Light transmitting plate
US4548773A (en) Injection molding method
EP0769999B1 (en) Lens thickness adjustment in plastic injection mold
US7794643B2 (en) Apparatus and method for molding object with enhanced transferability of transfer face and object made by the same
Han et al. Visualization analysis of the filling behavior of melt into microscale V‐grooves during the filling stage of injection molding
US6183235B1 (en) Electrically-operated injection molding machine
US5846466A (en) Method for forming a laminate structural molding
DE10221558A1 (en) Molding tool and method for manufacturing plastic articles
JP2004510607A (en) Method and apparatus for producing thick molded parts
US7329378B2 (en) Molding method, cooling apparatus and optical element
WO2007034815A1 (en) Mold, mold temperature regulation method, mold temperature regulation device, injection molding method, injection molding machine, and thermoplastic resin sheet

Legal Events

Date Code Title Description
PB01 Publication
C06 Publication
SE01 Entry into force of request for substantive examination
C10 Entry into substantive examination
GR01 Patent grant
C14 Grant of patent or utility model
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20091230

Termination date: 20160609

CF01 Termination of patent right due to non-payment of annual fee