Inventor
John C. H. Chang
Inventor
Naperville, IL, US
Overview
Patents· 52 as inventor
Public. Assignee & technology derived from the patent record. Each patent links to its LexDana page.
B41Mprimary
B41MPrinting, duplicating, marking, or copying processes14%
Y10TTechnical subjects covered by former us classification14%
D06MTreatment, not provided for elsewhere in class d06, of fibres, threads, yarns, fabrics, feathers or fibrous goods made from such materials11%
B42DBooks9%
Y10STechnical subjects covered by former uspc cross-reference art collections [xracs] and digests9%
G07DHandling of coins or valuable papers, e.g. testing, sorting by denominations, counting, dispensing, changing or depositing5%
B01DSeparation4%
B41JTypewriters3%
C01BNon-metallic elements3%
B44FSpecial designs or pictures3%
PatentTitleYear
10,991,837Configurations for solar cells, solar panels, and solar panel systems20216,802,870'Method for imparting soil and stain resistance to carpet'20046,736,857'Method for imparting soil and stain resistance to carpet'20046,723,438'Soil resistant curable laminate coating'20046,468,587'Treatment of fibrous substrates with acidic silsesquioxanes emulsions'20026,235,128'Carbon and alloy steels thermochemical treatments'20016,162,485'Fingerprinting system and method'20006,074,436'Carpet treatment composition comprising polycarboxylate salts'20006,060,428'Heat-sensitive chromogenic system'20005,970,875'Pressure-sensitive tamper evident system'19995,898,017'Multicolor chromogenic system having improved image quality'19995,880,063'Method of improving coverage of chromogenic reaction product'19995,759,327'Mailer printing method using ethylene vinyl acetate copolymer as a dual functional coating'19985,756,181'Repellent and soil resistant carpet treated with ammonium polycarboxylate salts'19985,744,201'Method for treating carpet using PH adjustment'19985,738,687'Method for treating carpets with polycarboxylate salts to enhance soil resistance and repellency'19985,644,352'Multicolor heat-sensitive verification and highlighting system'19975,618,063'Multicolor heat-sensitive verification and highlighting system'19975,612,541'Ultraviolet radiation monitoring device and use thereof'19975,605,873'Pressure-sensitive verification system and use thereof'19975,595,955'Verification method using pressure and heat-sensitive chromogenic system'19975,545,459'Business forms having dual-functional coating'19965,536,046'Heat sensitive system and use thereof'19965,492,599'Treated substrate having improved release properties'19965,484,169'Hidden entry system and image-developing device therefor'19965,431,452'Hidden entry system and image-developing device therefor'19955,427,415'Heat sensitive system and use thereof'19955,401,481'Processes for removing acid components from gas streams'19955,401,060'Document with heat and pressure sensitive chromogentic composition thereon'19955,395,138'Security document verification system with pressure-rupturable microcapsules'19955,344,191'Hidden entry system and use thereof'19945,270,015'Apparatus for removing sulfur from sulfur containing gases'19935,202,103'Removal of sulfur dioxide from gas streams'19935,100,643'Processes for removing acid components from gas streams'19925,098,774'Divalent metal salts of sulfonated novolak resins and methods for treating fibrous polyamide materials therewith'19925,047,221'Processes for removing sulfur from sulfur-containing gases'19915,047,222'Process for removing sulfur from sulfur-containing gases: high calcium fly-ash'19914,937,123'Process for providing polyamide materials with stain resistance'19904,875,901'Treating fibrous polyamide articles'19894,846,502'Tamper evident document and use thereof'19894,822,373'Process for providing polyamide materials with stain resistance with sulfonated novolak resin and polymethacrylic acd'19894,748,267'Fluorochemical biuret compounds and fibrous substrates treated therewith'19884,668,406'Fluorochemical biuret compositions and fibrous substrates treated therewith'19874,565,641'Blend of fluorochemical guanidines and poly(oxyalkylenes)'19864,540,497'Fluoroaliphatic radical-containing, substituted guanidines and fibrous substrates treated therewith'19854,511,641'Metal film imaging structure'19854,448,445'Pressure-sensitive record system'19844,426,476'Textile treatments'19844,425,386'Multi-sheet assembly using autogenous coating'19844,317,743'Process for making microcapsules and resulting product'19824,250,098'Chromogenic compounds'19814,195,103'Method of desensitizing carbonless paper'1980Career & activity timeline
Assembled from patent assignee/location history and declaration credentials.
1980–1982Patents assigned to WALLACE BUSINESS FORMS INC (2)· patent assignee history
1980–2000Based in Naperville, IL, US· patent location history
1984–2000Patents assigned to WALLACE COMPUTER SERVICES (21)· patent assignee history
1984–1998Patents assigned to MINNESOTA MINING & MFG (13)· patent assignee history
1984–2004Based in New Brighton, MN, US· patent location history
1985–1992Based in St. Paul, MN, US· patent location history
1991–1995Patents assigned to UNIV TEXAS (5)· patent assignee history
1991–1995Based in Cary, NC, US· patent location history
2000–2004Patents assigned to 3M INNOVATIVE PROPERTIES CO (5)· patent assignee history
2021Based in Alhambra, CA, US· patent location history
Inventor activity
Assignee and location history derived from the patent record.
Assignees
| Assignee | Patents | Span |
|---|---|---|
| WALLACE COMPUTER SERVICES | 21 | 1984–2000 |
| MINNESOTA MINING & MFG | 13 | 1984–1998 |
| 3M INNOVATIVE PROPERTIES CO | 5 | 2000–2004 |
| UNIV TEXAS | 5 | 1991–1995 |
| WALLACE BUSINESS FORMS INC | 2 | 1980–1982 |
Locations
| Location | Patents | Span |
|---|---|---|
| Naperville, Illinois, US | 24 | 1980–2000 |
| New Brighton, Minnesota, US | 16 | 1984–2004 |
| Cary, NC, US | 6 | 1991–1995 |
| St. Paul, Minnesota, US | 3 | 1985–1992 |
| Alhambra, California, US | 1 | 2021 |