Patent US4721739A successfully refreshed from Google Patents.
US4721739A
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US
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Erasable ink compositions
Assignee: BIC Corp
•
Filing: 1985-09-23
•
Granted: 1988-01-26
•
Expires: 2005-09-23
Abstract
Abstract This discovery relates to an erasable ink composition that can be erased using an ordinary pencil eraser. It can be used in ball point pens. Other applicators can be used. Of course, the composition includes colorant and solvent. The combination of a thermoplastic elastomer and plasticizer components are important to the composition. The elastomer is a block copolymer, and the plasticizer is advantageously an ester. Other components include lubricant, resin and dispersant. Concentration ranges for the colorant is from 0.1% to 60%, for the thermoplastic elastomer is from 8% to 30%; for the plasticizer is from 10% to 35%; for the solvent is from 10% to 40%; for the resin is up to about 12%; for the lubricant is up to about 8% and for the dispersant is up to about 2%, all percent by weight of the composition. The colorant is conventional; the thermoplastic elastomer and plasticizer are not conventional. The thermoplastic elastomer is styrene-butadiene-styrene; styrene-isoprene-styrene or styrene-polyolefin-styrene. The latter thermoplastic elastomer is advantageous. The advantageous plasticizer is dioctyl adipate. The weight ratio of thermoplastic elastomer to plasticizer is 0.1 to 3.0. Other advantageous components are a polyterpene resin, lauric acid and methyl cyclohexane solvent. The latter component has a Hildebrand solubility range from 6.9 to 7.8 (cal./cm 3 ) 1/2 . This discovery also relates to a process of forming erasable script.
Inventors
- 👤 Richard S. Brenneman
- 👤 Paul M. Drennan
- 👤 Irving J. Arons
- 👤 Alice H. Pincus
- 👤 Chaudhary M. Ramzan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:52
CPC Classifications
C; C09; C09D; C09D11/00; C09D11/16; C09D11/18
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
320 words
An erasable ink composition comprising: (a) a thermoplastic-elastomer block copolymer selected from the group consisting of styrene-butadiene-styrene, styrene-isoprene-styrene, styrene-polyolefin-styrene, and styrene-ethylene/butylene-styrene, said copolymer present in an amount from about 8% to about 30% by weight of the composition; (b) a plasticizer which is incompatible or of limited compatibility with the thermoplastic-elastomer copolymer in the absence of a solvent, said plasticizer being present in an amount from about 10% to about 35% by weight of the composition; (c) a solvent which acts as a solvent for the copolymer and is at least compatible with the plasticizer to produce a uniformly dispersed composition that flows on application of a small amount of force, said solvent having a Hildebrand solubility range from about 6.9 to 7.8 (cal./cm 3 ) 1/2 and being present in an amount from about 10% to about 40% by weight of the composition; (d) a colorant comprising a pigment or pigment dispersion in an amount from about 10% to about 60% by weight of the composition; (e) a resin in an amount of less than about 12% by weight of the composition; (f) a lubricant in an amount of less than about 8% by weight of the composition; and (g) an alkylated polyvinyl pyrrolidone or non-ionic surfactant-dispersant in an amount of less than about 2% by weight of the composition; said composition having a weight ratio of thermoplastic elastomer to plasticizer of about 0.1 to about 3 and a viscosity between about 48 and about 500 poise, and, when applied to a porous substrate as an ink, causing evaporation of said solvent without significant penetration of the composition into the porous substrate to produce a colored script comprising the copolymer and the incompatible plasticizer which script is erasable without smearing and in which the plasticizer gradually bleeds out of the copolymer due to their incompatibility with the copolymer physically crosslinking in time to form a non-erasable permanent colored script.
Claim 2
Dependent Claim
320 words
An erasable ink composition comprising: (a) a thermoplastic-elastomer block copolymer selected from the group consisting of styrene-butadiene-styrene, styrene-isoprene-styrene, styrene-polyolefin-styrene, and styrene-ethylene/butylene-styrene, said copolymer present in an amount from about 8% to about 30% by weight of the composition; (b) a plasticizer which is incompatible or of limited compatibility with the thermoplastic-elastomer copolymer in the absence of a solvent, said plasticizer being present in an amount from about 10% to about 35% by weight of the composition; (c) a solvent which acts as a solvent for the copolymer and is at least compatible with the plasticizer to produce a uniformly dispersed composition that flows on application of a small amount of force, said solvent having a Hildebrand solubility range from about 6.9 to 7.8 (cal./cm 3 ) 1/2 and being present in an amount from about 10% to about 40% by weight of the composition; (d) a colorant comprising a pigment or pigment dispersion in an amount from about 10% to about 60% by weight of the composition; (e) a resin in an amount of less than about 12% by weight of the composition; (f) a lubricant in an amount of less than about 8% by weight of the composition; and (g) an alkylated polyvinyl pyrrolidone or non-ionic surfactant-dispersant in an amount of less than about 2% by weight of the composition; said composition having a weight ratio of thermoplastic elastomer to plasticizer of about 0.1 to about 3 and a viscosity between about 48 and about 500 poise, and, when applied to a porous substrate as an ink, causing evaporation of said solvent without significant penetration of the composition into the porous substrate to produce a colored script comprising the copolymer and the incompatible plasticizer which script is erasable without smearing and in which the plasticizer gradually bleeds out of the copolymer due to their incompatibility with the copolymer physically crosslinking in time to form a non-erasable permanent colored script.
Claim 3
Dependent Claim
21 words
The composition according to claim 1 wherein the colorant is a dyestuff having a concentration from about 0.1% to about 6%.
Claim 4
Dependent Claim
99 words
The composition according to claim 1 wherein the colorant is Phthalocyanine Blue, 50% Pigment Blue 15 in Rosin, Pure Blue Oleate (Solvent Blue 5), 70% Victoria Blue (Pigment Blue 1) in Styrene-Ethylene/Butylene-Styrene, 60% Victoria Blue in Styrene-Ethylene/Butylene-Styrene, 40% Victoria Blue in Dioctyl Adipate, 50% Permanent Red 2B (Pigment Red 48) in Styrene-Ethylene/Butylene-Styrene, 40% Carbon Black (Pigment Black 6) in Dioctyl Adipate, Quinacridone Red, Watchung Red B, Watchung Red Y, Radiant Red/Orange, Perylene Red, Carbon Blacks, Permanent Yellow, Carbazole Violet, Victoria Blue, Rhodamine PMA, Violet 36, Oleate of Solvent Blue 4, Victoria Pure Blue BO Oleate or Methyl Violet Oleate.
Claim 5
Dependent Claim
12 words
The composition according to claim 1 wherein the plasticizer is an ester.
Claim 6
Dependent Claim
12 words
The composition according to claim 1 wherein the plasticizer is a hydrocarbon.
Claim 7
Dependent Claim
41 words
The composition according to claim 1 wherein the plasticizer is dioctyl phthalate, dioctyl adipate, decylbutyl phthalate, dibutyl phthalate, octyldecyl phthalate, butylbenzyl phthalate, dioctyl azaleate, dioctyl sebacate, butyl stearate, tricresyl phosphate, diiso octyl adipate, straight chain phthalate esters or polymeric ester plasticizers.
Claim 8
Dependent Claim
35 words
The composition according to claim 1 wherein the resin is cyclized rubber, glycerol esters of abietic acid, polyterpene resins, methyl styrene vinyl toluene copolymers, aromatic hydrocarbon resins, polystyrene resins, coumarone indene resins or polyterpene oligomers.
Claim 9
Dependent Claim
17 words
The composition according to claim 1 wherein the lubricant is lauric acid, stearic acid, polydimethylcyclosiloxane or chloroparaffin.
Claim 10
Dependent Claim
32 words
The composition according to claim 1 wherein the solvent is lactol spirits, heptane, methyl cyclohexane, isoparaffinic solvents, toluene, high-boiling aromatic solvents, xylene, ethyl benzene, ketones, butyl acetate, petroleum solvent or methyl cellosolve.
Claim 11
Dependent Claim
21 words
The composition according to claim 1 wherein the plasticizer is a hydrocarbon plasticizer and is paraffinic oil, aromatic or naphthenic oil.
Claim 12
Dependent Claim
13 words
The composition according to claim 1 suitable for use in ball point pens.
Claim 13
Dependent Claim
12 words
The composition according to claim 1 wherein the composition is under pressure.
Claim 14
Dependent Claim
18 words
The composition according to claim 12 wherein the pressure is exerted by mechanical means or by a gas.
Claim 15
Dependent Claim
21 words
The composition according to claim 1 wherein the weight ratio of thermoplastic elastomer to plasticizer is about 0.1 to about 1.5.
Claim 16
Dependent Claim
16 words
The composition according to claim 1 wherein the plasticizer is aliphatic, aromatic or a mixture thereof.
Claim 17
Dependent Claim
16 words
The composition according to claim 1 wherein the solvent is aliphatic, aromatic or a mixture thereof.
Claim 18
Dependent Claim
15 words
The composition according to claim 1 wherein said composition flows by gravity or when pressurized.
Claim 19
Dependent Claim
17 words
The composition according to claim 17 wherein the pressure is above atmospheric but below about 100 psig.
Claim 20
Dependent Claim
98 words
An initially substantially uniformly dispersed ink composition that flows on application of a small force, that becomes incompatible after temporarily retarding significant penetration of the composition into pores of a substrate so that the ink is erasable for a time using an ordinary pencil eraser consisting essentially of: ______________________________________
Concentration
(percent by weight of
Component the composition)
______________________________________
(a) victoria blue pigment
20-30%
dispersion in styrene-ethylene/
butylene-styrene or in dioctyl
adipate
(b) styrene-ethylene/butylene-
10-20%
styrene
(c) dioctyl phthalate or dioctyl
15-26%
adipate
(d) polyterpene resin less than about 10%
(e) lauric acid 2-4%
(f) methyl cyclohexane 20-30%
______________________________________
Claim 21
Dependent Claim
98 words
An initially substantially uniformly dispersed ink composition that flows on application of a small force, that becomes incompatible after temporarily retarding significant penetration of the composition into pores of a substrate so that the ink is erasable for a time using an ordinary pencil eraser consisting essentially of: ______________________________________
Concentration
(percent by weight of
Component the composition)
______________________________________
(a) victoria blue pigment
20-30%
dispersion in styrene-ethylene/
butylene-styrene or in dioctyl
adipate
(b) styrene-ethylene/butylene-
10-20%
styrene
(c) dioctyl phthalate or dioctyl
15-26%
adipate
(d) polyterpene resin less than about 10%
(e) lauric acid 2-4%
(f) methyl cyclohexane 20-30%
______________________________________
Claim 22
Dependent Claim
15 words
The composition according to claim 19 wherein the thermoplastic elastomer is styrene-isoprene-styrene rather than styrene-ethylene/butylene-styrene.
Claim 23
Dependent Claim
15 words
The composition according to claim 19 wherein the thermoplastic elastomer is styrene-butadiene-styrene rather than styrene-ethylene/butylene-styrene.
Claim 24
Dependent Claim
15 words
The composition according to claim 19 wherein the thermoplastic elastomer is styrene-polyolefin-styrene rather than styrene-ethylene/butylene-styrene.
Claim 25
Dependent Claim
292 words
An erasable ink composition consisting essentially of: (a) a thermoplastic-elastomeric block copolymer selected from the group consisting of styrene-butadiene-styrene, styrene-isoprene-styrene, styrene-polyolefin-styrene, and styrene-ethylene/butylene-styrene, said copolymer present in an amount from about 8% to about 30% by weight of the composition; (b) a plasticizer which is incompatible or of limited compatibility with the thermoplastic-elastomer copolymer in the absence of a solvent, said plasticizer being present in an amount from about 10% to about 35% by weight of the composition; (c) a solvent which acts as a solvent for the copolymer and is at least compatible with the plasticizer to produce a uniformly dispersed composition that flows on application of a small amount of force, said solvent present in an amount from about 10% to about 40% by weight of the composition; (d) a colorant comprising a pigment or pigment dispersion in an amount of from about 10% to about 60% by weight of the composition; (e) a resin in an amount of less than about 12% by weight of the composition; (f) a lubricant in an amount of less than about 8% by weight of the composition; and (g) an alkylated polyvinyl pyrrolidone or non-ionic surfactant-dispersant in an amount of less than about 2% by weight of the composition; said composition having a viscosity between about 48 and about 500 poise and, when applied to a porous substrate as an ink causing evaporation of said solvent without significant penetration of the composition into the porous substrate to produce a colored script comprising the copolymer and the incompatible plasticizer which script is erasable without smearing and in which the plasticizer gradually bleeds out of the copolymer due to their incompatibility, with the copolymer physically cross-linking in time to form a non-erasable permanent colored script.
Claim 26
Dependent Claim
292 words
An erasable ink composition consisting essentially of: (a) a thermoplastic-elastomeric block copolymer selected from the group consisting of styrene-butadiene-styrene, styrene-isoprene-styrene, styrene-polyolefin-styrene, and styrene-ethylene/butylene-styrene, said copolymer present in an amount from about 8% to about 30% by weight of the composition; (b) a plasticizer which is incompatible or of limited compatibility with the thermoplastic-elastomer copolymer in the absence of a solvent, said plasticizer being present in an amount from about 10% to about 35% by weight of the composition; (c) a solvent which acts as a solvent for the copolymer and is at least compatible with the plasticizer to produce a uniformly dispersed composition that flows on application of a small amount of force, said solvent present in an amount from about 10% to about 40% by weight of the composition; (d) a colorant comprising a pigment or pigment dispersion in an amount of from about 10% to about 60% by weight of the composition; (e) a resin in an amount of less than about 12% by weight of the composition; (f) a lubricant in an amount of less than about 8% by weight of the composition; and (g) an alkylated polyvinyl pyrrolidone or non-ionic surfactant-dispersant in an amount of less than about 2% by weight of the composition; said composition having a viscosity between about 48 and about 500 poise and, when applied to a porous substrate as an ink causing evaporation of said solvent without significant penetration of the composition into the porous substrate to produce a colored script comprising the copolymer and the incompatible plasticizer which script is erasable without smearing and in which the plasticizer gradually bleeds out of the copolymer due to their incompatibility, with the copolymer physically cross-linking in time to form a non-erasable permanent colored script.
Claim 27
Dependent Claim
99 words
The composition according to claim 23 wherein the colorant is Phthalocyanine Blue, 50% Pigment Blue 15 in Rosin, Pure Blue Oleate (Solvent Blue 5), 70% Victoria Blue (Pigment Blue 1) in Styrene-Ethylene/Butylene-Styrene, 60% Victoria Blue in Styrene-Ethylene/Butylene-Styrene, 40% Victoria Blue in Dioctyle Adipate, 50% Permanent Red 2B (Pigment Red 48) in Styrene-Ethylene/Butylene-Styrene, 40% Carbon Black (Pigment Black 6) in Dioctyl Adipate, Quinacridone Red, Watchung Red B, Watchung Red Y, Radiant Red/Orange, Perylene Red, Carbon Blacks, Permanent Yellow, Carbazole Violet, Victoria Blue, Rhodamine PMA, Violet 36, Oleate of Solvent Blue 4, Victoria Pure Blue BO Oleate or Methyl Violet Oleate.
Claim 28
Dependent Claim
21 words
The composition according to claim 23 wherein the plasticizer is a hydrocarbon, a paraffinic, aromatic or napthenic oil, or an ester.
Claim 29
Dependent Claim
41 words
The composition according to claim 25 wherein the plasticizer is dioctyl phthalate, dioctyl adipate, decylbutyl phthalate, dibutyl phthalate, octyldecyl phthalate, butylbenzyl phthalate, dioctyl azaleate, dioctyl sebacate, butyl stearate, tricresyl phosphate, diiso octyl adipate, straight chain phthalate esters or polymeric ester plasticizers.
Claim 30
Dependent Claim
35 words
The composition according to claim 23 wherein the resin is cyclized rubber, glycerol esters of abietic acid, polyterpene resins, methyl styrene vinyl toluene copolymers, aromatic hydrocarbon resins, polystyrene resins, coumarone indene resins or polyterpene oligomers.
Claim 31
Dependent Claim
17 words
The composition according to claim 23 wherein the lubricant is lauric acid, stearic acid, polydimethylcyclosiloxane or chloroparaffin.
Claim 32
Dependent Claim
16 words
The composition according to claim 23 wherein the solvent is aliphatic, aromatic or a mixture thereof.
Claim 33
Dependent Claim
32 words
The composition according to claim 29 wherein the solvent is lactol spirits, heptane, methyl cyclohexane, isoparaffinic solvents, toluene, high-boiling aromatic solvents, xylene, ethyl benzene, ketones, butyl acetate, petroleum solvent or methyl cellosolve.
Claim 34
Dependent Claim
12 words
The composition according to claim 23 wherein the composition is under pressure.
Claim 35
Dependent Claim
18 words
The composition according to claim 24 wherein the pressure is exerted by mechanical means or by a gas.
Claim 36
Dependent Claim
15 words
The composition according to claim 23 wherein said composition flows by gravity or when pressurized.
Claim 37
Dependent Claim
17 words
The composition according to claim 33 wherein the pressure is above atmospheric but below about 100 psig.
Claim 38
Dependent Claim
13 words
The composition according to claim 23 suitable for use in ball point pens.
References Cited (Backward Citations)
US27145A
Cited
US959010A
Cited
US3265765A
Cited
GB1092563A
Cited
US3875105A
Cited
US3595942A
Cited
US3880953A
Cited
USRE27145E
Cited
GB1429934A
Cited
US3784587A
Cited
US3972848A
Cited
US4097290A
Cited
US4011178A
Cited
US3993613A
Cited
US3997498A
Cited
US4039629A
Cited
US4244862A
Cited
US4059554A
Cited
UST959010I4
Cited
US4101484A
Cited
US4101482A
Cited
US4193676A
Cited
US4104326A
Cited
US4288399A
Cited
US4207359A
Cited
US4138378A
Cited
US4212676A
Cited
US4441928A
Cited
US4256494A
Cited
US4221490A
Cited
US4243500A
Cited
JPS55137166A
Cited
US4216132A
Cited
US4216131A
Cited
US4229338A
Cited
US4288567A
Cited
US4297260A
Cited
US4329264A
Cited
US4286077A
Cited
US4368076A
Cited
US4329262A
Cited
US4410643A
Cited
US4349639A
Cited
US4357431A
Cited
US4379867A
Cited
US4525216A
Cited
WO1983001625A1
Cited
US4391927A
Cited
US4390646A
Cited
US4389499A
Cited
US4419464A
Cited
US4367966A
Cited
US4471079A
Cited
US4407985A
Cited
US4606769A
Cited
US4509982A
Cited
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