Antisoiling hardcoat

• US 6,841,190 B2
• Filed: 10/21/2003
• Issued: 01/11/2005
• Est. Priority Date: 08/07/2000
• Status: Expired due to Term

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Liu, Junkang J., Fong, Bettie C., Kluge, Bruce D.
• Primary Examiner(s): Talbot, Brian K.
• Application Number:
  US10/690,425
• Publication Number:
  US 20040081764A1
• Time in Patent Office: 448 Days
• Field of Search: 427/64, 427/162, 427/164, 427/376.2, 427/376.1, 427/419.2, 427/207.1, 427/402, 427/289, 427/384, 427/385.5, 427/407.1, 427/365, 156/250, 156/256, 156/269
• US Class Current: 427/64
• CPC Class Codes: C08F 2/44 Polymerisation in the presence of compounding ingredients, e.g. plasticisers, dyestuffs, fillers
• CPC Class Codes: C08F 220/20 of polyhydric alcohols or phenols , e.g. 2-hydroxyethyl (meth)acrylate or glycerol mono-(meth)acrylate
• CPC Class Codes: C08F 222/103 of trialcohols, e.g. trimethylolpropane tri(meth)acrylate
• CPC Class Codes: C08F 290/06 Polymers provided for in subclass C08G
• CPC Class Codes: C08F 290/062 Polyethers
• CPC Class Codes: C08G 65/007 containing fluorine
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 53/00 Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
• CPC Class Codes: C09D 153/00 Coating compositions based on block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Coating compositions based on derivatives of such polymers
• CPC Class Codes: C09D 171/02 Polyalkylene oxides
• CPC Class Codes: C09D 4/00 Coating compositions, e.g. paints, varnishes or lacquers, based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond ; Coating compositions, based on monomers of macromolecular compounds of groups C09D183/00 - C09D183/16
• CPC Class Codes: C09D 4/06 Organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond in combination with a macromolecular compound other than an unsaturated polymer of groups C09D159/00 - C09D187/00
• CPC Class Codes: C09J 153/00 Adhesives based on block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Adhesives based on derivatives of such polymers
• CPC Class Codes: C09J 2433/00 Presence of (meth)acrylic polymer
• CPC Class Codes: C09J 7/22 Plastics; Metallised plastics
• CPC Class Codes: C09J 7/30 characterised by the adhesive composition
• CPC Class Codes: G01N 1/36 Embedding or analogous mounting of samples
• CPC Class Codes: G02B 21/34 Microscope slides, e.g. mounting specimens on microscope slides
• CPC Class Codes: G06F 1/1607 Arrangements to support accessories mechanically attached to the display housing G06F1/1603, G06F1/1605 take precedence
• CPC Class Codes: G06F 1/1626 : with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs]
• CPC Class Codes: G06F 1/1637 : Details related to the display arrangement, including those related to the mounting of the display in the housing
• CPC Class Codes: G06F 2200/1634 : Integrated protective display lid, e.g. for touch-sensitive display in handheld computer
• CPC Class Codes: G06F 3/041 : Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: H01J 29/868 : Screens covering the input or output face of the vessel, e.g. transparent anti-static coatings, X-ray absorbing layers
• CPC Class Codes: H04N 5/65 : Holding-devices for protective discs or for picture masks
• CPC Class Codes: H04N 9/3141 : Constructional details thereof details not peculiar to the presence of an electronic spatial light modulator G03B21/14
• CPC Class Codes: Y10T 156/1002 : with permanent bending or reshaping or surface deformation of self sustaining lamina
• CPC Class Codes: Y10T 428/1424 : Halogen containing compound
• CPC Class Codes: Y10T 428/1429 : Fluorine
• CPC Class Codes: Y10T 428/1476 : Release layer
• CPC Class Codes: Y10T 428/24802 : Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]
• CPC Class Codes: Y10T 428/24942 : including components having same physical characteristic in differing degree
• CPC Class Codes: Y10T 428/2495 : Thickness [relative or absolute]
• CPC Class Codes: Y10T 428/24967 : Absolute thicknesses specified
• CPC Class Codes: Y10T 428/24975 : No layer or component greater than 5 mils thick
• CPC Class Codes: Y10T 428/25 : Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/259 : Silicic material
• CPC Class Codes: Y10T 428/265 : 1 mil or less
• CPC Class Codes: Y10T 428/28 : Web or sheet containing structurally defined element or component and having an adhesive outermost layer
• CPC Class Codes: Y10T 428/2813 : Heat or solvent activated or sealable
• CPC Class Codes: Y10T 428/2848 : Three or more layers
• CPC Class Codes: Y10T 428/2891 : including addition polymer from alpha-beta unsaturated carboxylic acid [e.g., acrylic acid, methacrylic acid, etc.] Or derivative thereof
• CPC Class Codes: Y10T 428/3154 : Of fluorinated addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31544 : Addition polymer is perhalogenated
• CPC Class Codes: Y10T 428/31663 : As siloxane, silicone or silane
• CPC Class Codes: Y10T 428/31797 : Next to addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/3188 : Next to cellulosic
• CPC Class Codes: Y10T 428/31891 : Where addition polymer is an ester or halide
• CPC Class Codes: Y10T 428/31909 : Next to second addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31928 : Ester, halide or nitrile of addition polymer
• CPC Class Codes: Y10T 428/31935 : Ester, halide or nitrile of addition polymer

Abstract

An antisoiling hardcoated film comprising a substantially transparent substrate, a hardcoat layer comprising inorganic oxide particles dispersed in a binder matrix, and an antisoiling layer comprising a perfluoropolyether. The antisoiling layer can be very thin, thus reducing the cost of the perfluoropolyether. The film has very good scratch, smudge and glare resistance and very good interlayer adhesion and durability. The film can be in the form of a single flexible substrate or a stack of such substrates. The film or stack can be sized to fit the display screen of an electronic display device such as a personal digital assistant or cell phone.

Claims

1. A method for making an antisoiling hardcoat comprising coating and curing on a substrate a ceramer coating comprising inorganic oxide particles dispersed in a free-radically polymerizable binder matrix, and coating and curing atop the ceramer coating an antisoiling layer comprising a free-radically polymerizable fluorochemical.

2. A method for making a display element comprising applying to a substantially transparent substrate a curable hardcoat layer comprising inorganic oxide particles dispersed in a free-radically polymerizable binder matrix, curing the hardcoat layer, applying directly to the hardcoat layer a curable antisoiling layer comprising a perfluoropolyether, and polymerizing the antisoiling layer.

3. A method according to claim 2 wherein the perfluoropolyether has the formula:

Y—

C_aF_2aO)_b—

C_aF_2a—

Y

wherein each Y comprises a polymerizable group attached to a chain of randomly distributed, —

C_aF_2aO—

, repeating units, wherein each a is independently 1 to 7, b is the number of such repeating units, and b has a value from 1 to 300 such that the perfluoropolyether has a number average molecular weight of about 500 to about 20,000.

4. A method according to claim 2 wherein the substrate has first and second major surfaces with the hardcoat being applied to the first major surface, and further comprising applying an adhesive to the second major surface.

5. A method for making a screen protector for an information display, comprising:

a) applying to one side of a substantially transparent generally planar substrate a curable hardcoat layer comprising inorganic oxide particles dispersed in a free-radically polymerizable binder matrix, curing the hardcoat layer, applying directly to the hardcoat layer a curable antisoiling layer comprising a perfluoropolyether, and polymerizing the antisoiling layer; and

b) applying to the other side of the substrate an adhesive layer.

6. A method according to claim 5 wherein the perfluoropolyether has the formula:

Y—

(C_aF_2aO)_b—

C_aF_2a—

Y

wherein each Y comprises a polymerizable group attached to a chain of randomly distributed, —

C_aF_2aO—

, repeating units, wherein each a is independently 1 to 7, b is the number of such repeating units, and b has a value from 1 to 300 such that the perfluoropolyether has a number average molecular weight of about 500 to about 20,000.

7. A method for making screen protectors for portable electronic devices having a display screen, comprising:

a) applying to one side of a substantially transparent generally planar substrate a curable hardcoat layer comprising inorganic oxide particles dispersed in a free-radically polymerizable binder matrix, curing the hardcoat layer, applying to the hardcoat layer a curable antisoiling layer comprising a perfluoropolyether, and curing the antisoiling layer;

b) applying to the other side of the substrate an adhesive layer;

c) forming the coated substrate into a stack of sheets; and

d) cutting the stack so that the sheets will fit the display screen.

8. A method according to claim 7 wherein the perfluoropolyether has the formula:

Y—

(C_aF_2aO)_b—

C_aF_2a—

Y

wherein each Y comprises a polymerizable group attached to a chain of randomly distributed, —

C_aF_2aO—

, repeating units, wherein each a is independently 1 to 7, b is the number of such repeating units, and b has a value from 1 to 300 such that the perfluoropolyether has a number average molecular weight of about 500 to about 20,000.

9. A continuous, roll to roll manufacturing method for making a roughened screen protector sheet for information displays, comprising:

a) depositing a substantially solvent-free, curable ceramer composition comprising inorganic oxide particles dispersed in a free-radically polymemizable binder matrix into the nip region between a substantially transparent substrate and a roll having an average surface roughness of at least 0.1 micrometer;

b) moving the roll at a sufficient speed and while applying sufficient pressure to the nip to form a bead of the ceramer composition in the nip;

c) photocuring the ceramer composition through the substrate while the ceramer composition is against the roll;

d) removing the cured ceramer coating from the roll;

e) applying to the cured ceramer coating a curable antisoiling layer comprising a perfluoropolyether; and

f) curing the antisoiling layer.

10. A method according to claim 9, further comprising converting the coated substrate into sheets sized to fit an electronic display device screen.

11. A method according to claim 10, wherein the device comprises a portable device.

12. A method according to claim 10, wherein the device comprises a personal digital assistant.

13. A method according to claim 9, wherein the sheets are formed into a stack.