ARTICLES INJECTION MOLDED ON A WEB

• US 20120263919A1
• Filed: 06/22/2012
• Published: 10/18/2012
• Est. Priority Date: 06/20/2007
• Status: Active Grant

• Current Assignee: Solventum Intellectual Properties Company (Solventum Corp.)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Ferguson, Dennis E., Nayar, Satinder K., Benson, Peter T., Rendon, Stanley, Pochardt, Donald L., Dobbs, James N., Carlson, Daniel H.
• Granted Patent: US 8,637,136 B2
• Time in Patent Office: Days
• US Class Current: 428/156
• CPC Class Codes: A61M 2037/0053 Methods for producing microneedles
• CPC Class Codes: A61M 37/0015 by using microneedles
• CPC Class Codes: B01F 33/453 using supported or suspended stirring elements
• CPC Class Codes: B29C 2035/0811 using induction
• CPC Class Codes: B29C 2045/0094 injection moulding of small-sized articles, e.g. microarticles, ultra thin articles
• CPC Class Codes: B29C 2045/14942 Floating inserts, e.g. injecting simultaneously onto both sides of an insert through a pair of opposed gates
• CPC Class Codes: B29C 2045/2683 Plurality of independent mould cavities in a single mould
• CPC Class Codes: B29C 2791/008 Using vibrations during moulding
• CPC Class Codes: B29C 45/14 incorporating preformed parts or layers, e.g. injection moulding around inserts or for coating articles B29C45/1671 takes precedence
• CPC Class Codes: B29C 45/14016 Intermittently feeding endless articles, e.g. transfer films, to the mould B29C45/14262 takes precedence
• CPC Class Codes: B29C 45/1634 with a non-uniform dispersion of the moulding material in the article, e.g. resulting in a marble effect
• CPC Class Codes: B29C 45/1671 with an insert
• CPC Class Codes: B29C 45/27 Sprue channels ; Runner channels or runner nozzles
• CPC Class Codes: B29C 45/34 having venting means
• CPC Class Codes: B29C 45/568 Applying vibrations to the mould parts
• CPC Class Codes: B29C 45/73 of the mould B29C45/2642 and B29C45/2737 take precedence
• CPC Class Codes: B29D 11/00009 Production of simple or compound lenses
• CPC Class Codes: B29K 2069/00 Use of PC, i.e. polycarbonates or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2669/00 Use of PC, i.e. polycarbonates or derivatives thereof for preformed parts, e.g. for inserts
• CPC Class Codes: B29L 2011/0016 Lenses
• CPC Class Codes: B29L 2031/753 : Medical equipment; Accessories therefor bloodbags, medical bags B29L2031/7148; artificial eyes B29L2011/0008
• CPC Class Codes: B29L 2031/756 : Microarticles, nanoarticles
• CPC Class Codes: B32B 3/10 : characterised by a discontinuous layer, i.e. formed of separate pieces of material
• CPC Class Codes: G02B 3/00 : Simple or compound lenses
• CPC Class Codes: Y10T 428/24355 : Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]
• CPC Class Codes: Y10T 428/24479 : including variation in thickness
• CPC Class Codes: Y10T 428/24612 : Composite web or sheet
• CPC Class Codes: Y10T 428/24802 : Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]
• CPC Class Codes: Y10T 428/2481 : including layer of mechanically interengaged strands, strand-portions or strand-like strips
• CPC Class Codes: Y10T 428/24917 : including metal layer

Abstract

Articles enabled by an injection molding process that molds parts on a carrier web located between mold halves and uses ultrasonic energy to assist flow of polymer melt into the mold cavity. One such article is a carrier web having a high density of molded parts, i.e., bearing an array of molded articles adhered to the web in rows and columns, the articles being spaced closer (center-to-center or edge-to-edge) than the diagonal spacing between articles in the next adjacent row and next adjacent column. Another such article is a microneedle array on a land no more than 250 μm thick on which at least 60% of the microneedles across the array are filled (i.e., completely formed).

Claims

1. An article comprising the combination of a carrier web and an array of molded articles adhered to the carrier web which articles are characterized by microstructural features having an aspect ratio of at least 2:

1 said array comprising columns of molded articles aligned in the down-web direction and rows in the cross-web direction and in which array the closest center-to-center, or edge-to-edge, distance between the molded articles is closer than the diagonal center-to-center, or edge-to-edge, distance between a molded article and another molded article in the next adjacent row and the next adjacent column.

2. The article of claim 1 on which the molded articles comprise microneedle arrays.

3. The article of claim 1 on which the molded articles comprise lenses.

4. The article of claim 1 on which the molded articles comprise a polymer selected from the group consisting of polyphenyl sulfides, polycarbonates, polypropylenes, acetals, acrylics, polyetherimides, polybutylene terephthalates, polyethylene terephthalates and blends thereof.

5. The article of claim 1 of which the carrier web comprises a material selected from the group consisting of metal foil, porous or non-porous polymer, woven, non-woven or knitted cloth, or composites of such materials.

6. The article of claim 1 of which the carrier web comprises a polymer selected from the group consisting of polypropylenes, polycarbonates, polyethylenes, polyimides and polyesters.

7. The article of claim 1 characterized by an absence of sprues and runners.

8. A microneedle array made of polymeric material comprising a multiplicity of microneedles having a height of 20 to 1000 micrometers and an aspect ratio greater than 2:

1 on a land, characterized by at least 60 percent of the microneedles across the array being filled, the term filled meaning that the microneedle mold cavities used to form the microneedles were filled with polymeric material to form complete microneedles.

9. The microneedle array of claim 8 comprising 10 to 1288 microneedles.

10. The microneedle array of claim 8 comprised of a polymer selected from the group consisting of polyphenyl sulfides, polycarbonates, polypropylenes, acetals, acrylics, polyetherimides, polybutylene terephthalates, polyethylene terephthalates, and blends thereof.

11. The microneedle array of claim 8 having a land no more than 250 micrometers thick