# US 8,784,235 B2 · Golf ball with negative hardness gradient core > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,784,235 B2 - Document ID: US8784235B2 - Status: Granted - Kind: B2 - Application number: 14/016,466 - Filed: 2013-09-03 - Published: 2014-01-09 - Granted: 2014-07-22 - Earliest claimed: 2007-07-03 - Assignees: Acushnet Company - Applicants: Acushnet Company - Inventors: Michael J. Sullivan; Brian Comeau; Douglas S. Goguen; David A. Bulpett - Web page: https://patentgrep.com/patent/US8784235B2 ## CPC - A63B 37/0063: {Hardness gradient} - A63B 37/00621: {Centre hardness} - A63B 37/00622: {Surface hardness} - A63B 37/0092: {Hardness distribution amongst different ball layers} - A63B 37/0064: {Diameter} - A63B 37/0075: {Three piece balls, i.e. cover, intermediate layer and core} - A63B 37/0076: {Multi-piece balls, i.e. having two or more intermediate layers} - A63B: APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT (apparatus for passive exercising, massage A61H) ## Abstract Golf ball comprising a single layer core formed from a substantially homogenous formulation and comprising: geometric center and outer surface; inner core region disposed about the geometric center, outer core region adjacent the outer surface, and intermediate core region disposed between the inner and outer core regions and extending radially from about 10 mm to about 16 mm from the geometric center. A first hardness is disposed within the inner core region, a second hardness is disposed within the outer core region, and a third hardness of from about 40 Shore C to about 95 Shore C (or about 30 Shore D to about 70 Shore D) is disposed within the intermediate core region and is greater than each of the first and second hardnesses. At least one hardness in the outer core region is substantially the same as or less than a hardness in the inner core region. ## Claims ### Claim 1 A golf ball comprising: a single layer core and a cover layer disposed about the single layer core; said single layer core being formed from a substantially homogenous formulation and comprising a geometric center and an outer surface; the single layer core further comprising an inner core region disposed about the geometric center, an outer core region adjacent the outer surface, and an intermediate core region disposed between the inner and outer core regions and extending radially from about 10 mm to about 16 mm from the geometric center; the single layer core further having a first hardness disposed within the inner core region, a second hardness disposed within the outer core region, and a third hardness disposed within the intermediate core region, wherein the third hardness is from about 40 Shore C to about 95 Shore C and is greater than the first hardness and the second hardness, and wherein there is at least one hardness in the outer core region that is substantially the same as or less than a hardness in the inner core region. ### Claim 2 (depends on 1) The golf ball of claim 1, wherein the single layer core has a diameter of from about 30 mm to about 42 mm. ### Claim 3 (depends on 1) The golf ball of claim 1, wherein the inner core region has a hardness that is adjacent the intermediate core region and greater than a hardness of the geometric center. ### Claim 4 (depends on 1) The golf ball of claim 1, wherein the outer core region has a hardness that is adjacent the intermediate core region and greater than a hardness of the outer surface. ### Claim 5 (depends on 1) The golf ball of claim 1, wherein the inner core region has a hardness at about 8 mm from the geometric center that is: greater than a hardness of the geometric center; and less than a hardness that is within the inner core region and adjacent the intermediate core region. ### Claim 6 (depends on 1) The golf ball of claim 1, wherein the outer core region has a hardness that is: greater than a hardness of the outer surface; and less than a hardness that is within the outer core region and adjacent the intermediate core region. ### Claim 7 (depends on 1) The golf ball of claim 1, further comprising a second cover layer disposed between the single core layer and the cover layer. ### Claim 8 A golf ball comprising: a single layer core and a cover layer disposed about the single layer core; said single layer core being formed from a substantially homogenous formulation and comprising a geometric center and an outer surface; the single layer core further comprising an inner core region disposed about the geometric center, an outer core region adjacent the outer surface, and an intermediate core region disposed between the inner and outer core regions and extending radially from about 10 mm to about 16 mm from the geometric center; the single layer core further having a first hardness disposed within the inner core region, a second hardness disposed within the outer core region, and a third hardness disposed within the intermediate core region, wherein the third hardness is from about 30 Shore D to about 70 Shore D and is greater than the first hardness and the second hardness, and wherein there is at least one hardness in the outer core region that is substantially the same as or less than a hardness in the inner core region. ### Claim 9 (depends on 8) The golf ball of claim 8, wherein the single layer core has a diameter of from about 30 mm to about 42 mm. ### Claim 10 (depends on 1) The golf ball of claim 1, wherein the inner core region has a hardness that is adjacent the intermediate core region and greater than a hardness of the geometric center. ### Claim 11 (depends on 8) The golf ball of claim 8, wherein the outer core region has a hardness that is adjacent the intermediate core region and greater than a hardness of the outer surface. ### Claim 12 (depends on 8) The golf ball of claim 8, wherein the inner core region has a hardness at about 8 mm from the geometric center that is: greater than a hardness of the geometric center; and less than a hardness that is within the inner core region and adjacent the intermediate core region. ### Claim 13 (depends on 8) The golf ball of claim 8, wherein the outer core region has a hardness that is: greater than a hardness of the outer surface; and less than a hardness that is within the outer core region and adjacent the intermediate core region. ### Claim 14 (depends on 8) The golf ball of claim 8, further comprising a second cover layer disposed between the single core layer and the cover layer.