Reverse thermal gels and the use thereof for rapid prototyping

• US 6,863,859 B2
• Filed: 08/15/2002
• Issued: 03/08/2005
• Est. Priority Date: 08/16/2001
• Status: Active Grant

• Current Assignee: Stratasys Incorporated
• Original Assignee: Objet Geometries
• Inventors: Levy, Avraham
• Primary Examiner(s): BERMAN, SUSAN W
• Application Number:
  US10/218,514
• Publication Number:
  US 20030107158A1
• Time in Patent Office: 936 Days
• Field of Search: 264/401, 264/494, 264/496, 264/331.11, 264/331.12, 264/331.13, 264/331.14, 264/331.15, 264/331.16, 264/331.17, 264/331.18, 264/331.21, 264/331.22, 264/313, 264/317, 264/308, 264/319, 430/494, 430/496, 430/270.1, 430/280.1, 430/281.1, 430/269
• US Class Current: 264/401
• CPC Class Codes: B29C 35/02 Heating or curing, e.g. crosslinking or vulcanizing during moulding, e.g. in a mouldcold vulcanisation B29C35/18 ; vulcanising tyres, presses therefor B29D30/0601
• CPC Class Codes: B29C 64/106 using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material
• CPC Class Codes: B29C 64/40 Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof
• CPC Class Codes: B29C 67/24 characterised by the choice of material
• CPC Class Codes: B29K 2995/0012 having particular thermal properties
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 70/00 Materials specially adapted for additive manufacturing
• CPC Class Codes: C08L 1/14 Mixed esters, e.g. cellulose acetate-butyrate
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 71/02 Polyalkylene oxides
• CPC Class Codes: C08L 75/16 having terminal carbon-to-carbon unsaturated bonds

Abstract

The present invention relates to novel polymeric compositions that exhibit Reverse Thermal Gelation (RTG) properties for use as Support Materials (SM) in the manufacture of three-dimensional objects. These polymers are Temperature Sensitive Polymers that respond with a significant change of properties to a small change in temperature. Temperature Sensitive Polymers exhibit cloud point (CP) or lower critical solution temperature (LCST) in aqueous solutions. Water-soluble Temperature Sensitive Polymers are chosen to give low viscosity liquid at low temperature when dissolved in water and by that to permit easy dispensing at low temperature. Raising the temperature above their gelation temperature (T_gel) will result in solidification of the composition. At its gel position the material has favorable characteristics as a support and building material. The gel layers have the appropriate toughness and dimensional stability to support the model layers during the building process. After the building process is completed the gel can be cooled down to a temperature below its T_gel so the gel can liquefy and be removed easily by rinsing with water.

Claims

1. A method for building a three-dimensional object by three dimensional printing, said method comprising the steps of:

dispensing a building composition comprising;

at least one Temperature Sensitive Polymer, wherein said composition exhibits Reverse Thermal Gelation (RTG) properties; and

at least one surface-active agent; and

gelating said building composition by increasing temperature to above the gelation temperature of said composition, thereby constructing said three dimensional object.

2. The method according to claim 1, wherein said Temperature Sensitive Polymer is a water-soluble Temperature Sensitive Polymer.

3. The method according to claim 2, wherein said water-soluble Temperature Sensitive Polymer is an ABA triblock oligomer, wherein A and B are oligomers.

4. The method according to claim 3, wherein A is a hydrophilic oligomer and B is a hydrophobic oligomer.

5. The method according to claim 3, wherein A is a hydrophobic oligomer and B is a hydrophilic oligomer.

6. The method according to claim 3, wherein A and B comprise aliphatic polyether and/or polyester units.

7. The method according to claim 3, wherein A is poly(ethylene oxide) and B is poly(propylene oxide).

8. The method according to claim 2, wherein said water-soluble Temperature Sensitive Polymer is a multi block polymer of (ABA-X)_m, organized at random or repetitive configuration, wherein wherein A and B are oligomers, m is an integer of 1-30, and X is a chain extender.

9. The method according to claim 8, wherein said X is selected from the group consisting of di, tri and poly isocyanates, di, tri and poly carboxylic acids, diacyl halides, triphosgene or any combination thereof.

10. The method according to claim 8, wherein A is a hydrophilic oligomer and B is a hydrophobic oligomer.

11. The method according to claim 8, wherein A is a hydrophobic oligomer and B is a hydrophilic oligomer.

12. The method according to claim 8, wherein said multi block polymer of ABA is a polyurethane, polycarbonate, polyester or any combination thereof.

13. The method according to claim 2, wherein said Temperature Sensitive Polymers are poly (N-substituted (meth)acrylamides).

14. The method according to claim 13, wherein said poly (N-substituted (meth)acrylamides) is poly N-isopropyl (meth)acrylamides).

15. The method according to claim 2, wherein said Temperature Sensitive Polymer is a poly vinyl alcohol derivative, hydroxypropyl methylcellulos, Ethyl hydroxyethyl cellulose (EHEC) or any combination thereof.

16. The method according to claim 1, wherein said surface-active agent is capable of reducing the surface tension of said composition to about 30 dyne/cm.

17. The method according to claim 1, wherein said surface-active agent is a silicon surface-active agent additive, a fluoro-based surface-active agent or a combination thereof.

18. The method according to claim 1, wherein said composition further comprises:

at least one photo curable reactive component;

at least one photo-initiator; and

at least one stabilizer,

whereby said method further comprises the step of curing said building composition, thereby increases the strength of said building composition.

19. The method according to claim 18, wherein said photo curable reactive component is a (meth)acrylic component.

20. The method according to claim 19, wherein said (meth)acrylic component is a (meth)acrylic monomer, a (meth)acrylic oligomer, or a combination thereof.

21. The method according to claim 19, wherein said (meth)acrylic component is a polyethylene glycol mono or di (meth)acrylated, polyether triacrylate or any combination thereof.

22. The method according to claim 18, wherein said reactive component is a water miscible component that is, after irradiation or curing, capable of dissolving or swelling upon exposure to water or to an alkaline or acidic water solution.

23. The method according to claim 22, wherein said water miscible component is an acryloyl morpholine, a (meth)acrylated urethane oligomer derivative of polyethylene glycol, a partially (meth)acrylated polyol oligomer, an (meth)acrylated oligomer having hydrophillic substituents, or any combination thereof.

24. The method according to claim 23, wherein said hydrophilic substituent is an acidic substituent, an amino substituent, a hydroxy substituent or any combination thereof.

25. The method according to claim 19, wherein said (meth)acrylic component is beta-carboxyethyl acrylate.

26. The method according to claim 19, wherein said reactive component is a molecule having one or more vinyl ether substituents.

27. The method according to claim 26, wherein said vinyl ether substituent is hydroxy-butyl vinyl ether.

28. The method according to claim 18, wherein said photo-initiator is a free radical photo-initiator, a cationic photo-initiator, or any combination thereof.

29. The composition according to claim 28, wherein said free radical photo-initiator is benzophenone, an acylphosphine oxide, an alpha-amino ketone or any combination thereof.

30. The method according to claim 28, wherein said cationic photo-initiator is selected from the group consisting of aryldiazonium salts, diaryliodonium salts, triarylsulphonium salts, triarylselenonium salts, triarylsolfonium hexafluoroantimonate salts.

31. The method according to claim 28, wherein said photo-initiator further comprises a co-initiator component.

32. The method according to claim 31 wherein said co-initiator component is triethanol amine.

33. The method according to claim 18, wherein said stabilizer is 4-methoxy phenol.

34. A 3-dimensional object prepared by the method according to claim 1.

35. A method for supporting a three-dimensional object during construction, said method comprising the step of:

contacting said object with a support composition, said support composition comprising;

at least one Temperature Sensitive Polymer, wherein said support composition exhibits Reverse Thermal Gelation (RTG) properties; and

at least one surface-active agent; and

gelating said support composition by increasing temperature to above the gelation temperature of said composition, thereby supporting said three dimensional object.

36. The method according to claim 35, further comprising the step of removing said support composition after construction of said object by cooling said support composition to a temperature below the gelation temperature of said composition.

37. The method according to claim 35, wherein said construction comprises Rapid Prototyping (RP), Rapid Manufacturing (RM) or Rapid Tooling (RT).

38. The method according to claim 35, wherein said construction comprises rapid tooling (RT), wherein said rapid tooling (RT) comprises

building a casting mold with said support composition for holding said object;

and

building said object in said mold.

39. The method according to claim 38, further comprising the step of removing said mold by cooling said support composition to a temperature below the gelation temperature of said composition.

40. The method according to claim 35, wherein said construction comprises Rapid Manufacturing (RM), wherein said rapid manufacturing (RM) comprises direct manufacturing of finished parts.

41. The method according to claim 35, wherein said Temperature Sensitive Polymer is a water-soluble Temperature Sensitive Polymer.

42. The method according to claim 41, wherein said water-soluble Temperature Sensitive Polymer is an ABA triblocks oligomer, wherein A and B are oligomers.

43. The method according to claim 42, wherein A is a hydrophilic oligomer and B is a hydrophobic oligomer.

44. The method according to claim 42, wherein A is a hydrophobic oligomer and B is a hydrophilic oligomer.

45. The method according to claim 42, wherein A and B comprise aliphatic polyether and/or polyester units.

46. The method according to claim 42, wherein A is poly(ethylene oxide) and B is poly(propylene oxide).

47. The method according to claim 41, wherein said water-soluble Temperature Sensitive Polymer is a multi block polymer of (ABA-X)_m, organized at random or repetitive configuration, wherein A and B are oligomers, m is an integer of 1-30, and X is a chain extender.

48. The method according to claim 47, wherein said X is selected from the group consisting of di, tri and poly isocyanates, di, tri and poly carboxylic acids, diacyl halides, triphosgene or any combination thereof.

49. The method according to claim 47, wherein A is a hydrophilic oligomer and B is a hydrophobic oligomer.

50. The method according to claim 47, wherein A is a hydrophobic oligomer and B is a hydrophilic oligomer.

51. The method according to claim 47, wherein said multi block polymer of ABA is a polyurethane, polycarbonate, polyester or any combination thereof.

52. The method according to claim 41, wherein said Temperature Sensitive Polymers are poly (N-substituted (meth)acrylamides).

53. The method according to claim 47, wherein said poly (N-substituted (meth)acrylamides) is poly (N-isopropyl (meth)acrylamides).

54. The method according to claim 41, wherein said Temperature Sensitive Polymer is a poly vinyl alcohol derivative, hydroxypropyl methylcellulose, Ethyl hydroxyethyl cellulose (EHEC) or any combination thereof.

55. The method according to claim 35, wherein said surface-active agent is capable of reducing the surface tension of said composition to about 30 dyne/cm.

56. The method according to claim 35, wherein said surface-active agent is a silicon surface-active agent additive, a fluoro-based surface-active agent additive, or a combination thereof.

57. The method according to claim 35, wherein said composition further comprises:

at least one photo curable reactive component;

at least one photo-initiator; and

at least one stabilizer,

whereby said method further comprises the step of curing said support composition, thereby increases the strength of said support composition.

58. The method according to claim 57, wherein said photo curable reactive component is a (meth)acrylic component.

59. The method according to claim 58, wherein said (meth)acrylic component is a (meth)acrylic monomer, a (meth)acrylic oligomer, or a combination thereof.

60. The method according to claim 58, wherein said (meth)acrylic component is a polyethylene glycol mono or di (meth)acrylated, polyether triacrylate or any combination thereof.

61. The method according to claim 57, wherein said reactive component is a water miscible component that is, after irradiation or curing, capable of dissolving or swelling upon exposure to water or to an alkaline or acidic water solution.

62. The method according to claim 61, wherein said water miscible component is an acryloyl morpholine, a (meth)acrylated urethane oligomer derivative of polyethylene glycol, a partially (meth)acrylated polyol oligomer, an (meth)acrylated oligomer having hydrophillic substituents, or any combination thereof.

63. The method according to claim 62, wherein said hydrophilic substituent is an acidic substituent, amino substituent, hydroxy substituent or any combination thereof.

64. The method according to claim 58, wherein said (meth)acrylic component is beta-carboxyethyl acrylate.

65. The method according to claim 57, wherein said reactive component is a molecule having one or more vinyl ether substituents.

66. The method according to claim 65, wherein said vinyl ether substituent is hydroxy-butyl vinyl ether.

67. The method according to claim 57, wherein said photo-initiator is a free radical photo-initiator, a cationic photo-initiator, or any combination thereof.

68. The composition according to claim 67, wherein said free radical photo-initiator is a benzophenone, an acylphosphine oxide, an alpha-amino ketone or any combination thereof.

69. The method according to claim 67, wherein said cationic photo-initiator is selected from the group consisting of aryldiazonium salts, diaryliodonium salts, triarylsulphonium salts, triarylselenonium salts, triarylsolfonium hexafluoroantimonate salts.

70. The method according to claim 67, wherein said photo-initiator further comprises a co-initiator component.

71. The method according to claim 70 wherein said co-initiator component is triethanol amine.

72. The method according to claim 57, wherein said stabilizer is 4-methoxy phenol.

73. A 3-dimensional object prepared by a method according to claim 35.

74. A method for the preparation of a three-dimensional object by three-dimensional printing comprising the step of:

dispensing a model composition from a first dispenser, said model composition comprising;

at least one reactive component;

at least one photo-initiator;

at least one surface-active agent; and

at least one stabilizer,

dispensing a support composition from a second dispenser, said support composition comprising;

at least one Temperature Sensitive Polymer;

at least one surface-active agent; and

combining said model composition and said support composition in predetermined proportions to produce a multiplicity of construction layers for forming said three-dimensional object;

whereby said model composition is cured resulting in a solid form, and

whereby said support composition is gelated by increasing temperature to above the gelation temperature of said composition, thereby resulting in a gel form.

75. The method according to claim 74, wherein said preparation of a three-dimensional object further comprising the step of removing said support composition after construction of said object by cooling said support composition to a temperature below the gelation temperature of said composition.

76. The method according to claim 74, wherein said reactive component of said model composition is selected from the group consisting of an acrylic component, a molecule having one or more epoxy substituents, a molecule having one or more vinyl ether substituents, vinylpyrolidone, vinylcaprolactam, or any combination thereof.

77. The method according to claim 74, wherein said reactive component of said model composition is comprised of at least one acrylic component.

78. The method according to claim 77, wherein said acrylic component is an acrylic monomer, an acrylic oligomer, an acrylic crosslinker, or any combination thereof.

79. The method according to claim 77, wherein said reactive component of said model composition further comprises a molecule having one or more epoxy substituents, a molecule having one or more vinyl ether substituents, vinylcaprolactam, vinylpyrolidone, or any combination thereof.

80. The method according to claim 77, wherein said reactive component of said model composition further comprises vinylcaprolactam.

81. The method according to claim 77, wherein said reactive component of said model composition is a molecule having one or more vinyl ether substituents.

82. The method according to claim 74, wherein said reactive component of said model composition is a molecule having one or more epoxy substituents.

83. The method according to claim 74, wherein said photo-initiator of said model composition is a free radical photo-initiator, a cationic photo-initiator or any combination thereof.

84. The method according to claim 74, wherein said model composition further comprises at least one pigment and at least one dispersant.

85. The method according to claim 74, wherein said pigment is a white pigment, an organic pigment, an inorganic pigment, a metal pigment or a combination thereof.

86. The method according to claim 74, wherein said model composition further comprises a dye.

87. The method according to claim 74, wherein said Temperature Sensitive Polymer is a water-soluble Temperature Sensitive Polymer.

88. The method according to claim 87, wherein said water-soluble Temperature Sensitive Polymer is an ABA triblocks oligomer, wherein A and B are oligomers.

89. The method according to claim 88, wherein A is a hydrophilic oligomer and B is a hydrophobic oligomer.

90. The method according to claim 88, wherein A is a hydrophobic oligomer and B is a hydrophilic oligomer.

91. The method according to claim 88, wherein A and B comprise aliphatic polyether and/or polyester units.

92. The method according to claim 88, wherein A is poly(ethylene oxide) and B is poly(propylene oxide).

93. The method according to claim 87, wherein said water-soluble Temperature Sensitive Polymer is a multi block polymer of (ABA-X)_m, organized at random or repetitive configuration, wherein A and B are oligomers, m is an integer of 1-30, and X is a chain extender.

94. The method according to claim 93, wherein said X is selected from the group consisting of di, tri and poly isocyanates, di, tri and poly carboxylic acids, diacyl halides, triphosgene, or any combination thereof.

95. The method according to claim 93, wherein A is a hydrophilic oligomer and B is a hydrophobic oligomer.

96. The method according to claim 93, wherein A is a hydrophobic oligomer and B is a hydrophilic oligomer.

97. The method according to claim 93, wherein said multi block polymer of ABA is a polyurethane, polycarbonate, polyester or any combination thereof.

98. The method according to claim 84, wherein said Temperature Sensitive Polymers are poly (N-substituted (meth)acrylamides).

99. The method according to claim 98, wherein said poly (N-substituted (meth)acrylamides) is poly (N-isopropyl (meth)acrylamides).

100. The method according to claim 87, wherein said Temperature Sensitive Polymer is a poly vinyl alcohol derivative, hydroxypropyl methylcellulose, Ethyl hydroxyethyl cellulose (EHEC) or any combination thereof.

101. The method according to claim 74, wherein said surface-active agent is capable of reducing the surface tension of said composition to about 30 dyne/cm.

102. The method according to claim 74, wherein said surface-active agent is a silicon surface-active agent additive, a fluoro-based surface-active agent additive, or a combination thereof.

103. The method according to claim 74, wherein said Support composition further comprises:

at least one photo curable reactive component;

at least one photo-initiator, and

at least one stabilizer,

whereby said method further comprises the step of curing said support composition, thereby increases the strength of said composition.

104. The method according to claim 103, wherein said photo curable reactive component is a (meth)acrylic component.

105. The method according to claim 104, wherein said (meth)acrylic component is a (meth)acrylic monomer, a (meth)acrylic oligomer, or a combination thereof.

106. The method according to claim 104, wherein said (meth)acrylic component is a polyethylene glycol mono or di (meth)acrylated, polyether triacrylate or any combination thereof.

107. The method according to claim 103, wherein said reactive component is a water miscible component that is, after irradiation or curing, capable of dissolving or swelling upon exposure to water or to an alkaline or acidic water solution.

108. The method according to claim 107, wherein said water miscible component is an acryloyl morpholine, a (meth)acrylated urethane oligomer derivative of polyethylene glycol, a partially (meth)acrylated polyol oligomer, an (meth)acrylated oligomer having hydrophillic substituents, or any combination thereof.

109. The method according to claim 108, wherein said hydrophilic substituent is an acidic substituents, amino substituent, hydroxy substituent or any combination thereof.

110. The method according to claim 104, wherein said (meth)acrylic component is beta-carboxyethyl acrylate.

111. The method according to claim 104, wherein said reactive component is a molecule having one or more vinyl ether substituents.

112. The method according to claim 111, wherein said vinyl ether substituent is hydroxy-butyl vinyl ether.

113. The method according to claim 103, wherein said photo-initiator is a free radical photo-initiator, a cationic photo-initiator, or any combination thereof.

114. The composition according to claim 113, wherein said free radical photo initiator is a benzophenone, an acylphosphine oxide, an alpha-amino ketone or any combination thereof.

115. The method according to claim 113, wherein said cationic photo-initiator is selected from the group consisting of aryldiazonium salts, diaryliodonium salts, triarylsulphonium salts, triarylselenonium salts, triarylsolfonium hexafluoroantimonate salts.

116. The method according to claim 113, wherein said photo-initiator further comprises a co-initiator component.

117. The method according to claim 116 wherein said co-initiator component is triethanol amine.

118. The method according to claim 74, wherein said stabilizer is 4-methoxy phenol.

119. The method according to claim 103, wherein said stabilizer is 4-methoxy phenol.

120. The method according to claim 74, further comprising the step of forming a multiplicity of support layers for supporting said object.

121. A 3-dimensional object prepared by a method according to claim 74.